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Université de Neuchâtel
1.
Devenoges, Laurent.
Évaluation métrologique de l'étalon primaire de fréquence à
atomes froids de césium FOCS-2.
Degree: 2012, Université de Neuchâtel
URL: http://doc.rero.ch/record/30405
► Ce travail de recherche s'inscrit dans la continuité des études, menées depuis 20 ans à l'Observatoire Cantonal de Neuchâtel, pour réaliser un étalon primaire de…
(more)
▼ Ce travail de recherche s'inscrit dans la continuité
des études, menées depuis 20 ans à l'Observatoire Cantonal de
Neuchâtel, pour réaliser un étalon primaire de fréquence
fonctionnant avec un jet continu d'atomes froids et lents. Ces
développements théoriques et expérimentaux ont conduit à la
construction de deux horloges à fontaine continue FOCS-1 et FOCS-2.
Ce document expose les dernières améliorations et les premières
mesures d'évaluation du second étalon primaire de fréquence
effectuées ces trois dernières années au Laboratoire
Temps-Fréquence de l'Université de Neuchâtel. Dans la
première partie, nous présentons le développement et
l'implémentation d'une nouvelle méthode de préparation d'état
utilisée pour améliorer la stabilité de fréquence à court terme de
l'étalon. Nous avons montré qu'en utilisant un schéma de pompage
optique à deux lasers, il est possible de combiner simultanément
préparation d'état et refroidissement Sisyphe. Grâce à cette
technique, nous avons réussi à préparer 60% des atomes dans le
niveau
|<i>F</i>=3,<i>m</i>
F=0>,
soit un gain d'un facteur 6.5 du signal utile par rapport à la
situation sans préparation d'état. Nous avons montré que ce nouveau
schéma de pompage optique n'affectait pas le rapport
signal-sur-bruit de l'horloge et nous avons mesuré une stabilité de
6•10
-14<i>τ</i>
-1/2
avec préparation d'état. Ce résultat constitue la première
démonstration expérimentale que la fontaine continue n'est pas
limitée par le bruit de phase de l'oscillateur local.
Dans la deuxième partie de cette étude, nous avons analysé et
mesuré quatre effets systématiques dont l'influence ou la méthode
d'évaluation sont propres au fonctionnement continu de l'horloge.
Le déplacement radiatif provoqué par la lumière des faisceaux de
refroidissement et le déplacement Zeeman du
2
e ordre ont ainsi été évalués avec une
incertitude inférieure à 10
-15. Le
déplacement de fréquence lié à la phase du mode électromagnétique
présent dans la cavité micro-onde coaxiale a fait l'objet d'études
préliminaires. Nous avons mis en évidence la présence d'un
important gradient de phase radial dans la section des trous de
passage des atomes. Si nous ne sommes aujourd'hui pas capables
d'évaluer cet effet en conditions de fonctionnement, le problème a
été identifié et nous pensons être en mesure de le résoudre
rapidement. Finalement, nous avons cherché à mesurer la
perturbation de fréquence provoquée par les interactions entre les
atomes du jet continu. Bien qu'à ce jour la présence des gradients
de phase limite la précision de cette évaluation, les mesures
effectuées sont compatibles avec les prédictions théoriques de
-3.3•10
-16. En décembre 2011, la
fontaine continue FOCS-2 présentait au Laboratoire Temps-Fréquence
de l'Université de Neuchâtel un budget d'incertitude intermédiaire
de (60.5±1.6)•10
-15.
Advisors/Committee Members: Gaetano (Dir.), Pierre (Codir.).
Subjects/Keywords: metrology
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Devenoges, L. (2012). Évaluation métrologique de l'étalon primaire de fréquence à
atomes froids de césium FOCS-2. (Thesis). Université de Neuchâtel. Retrieved from http://doc.rero.ch/record/30405
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Devenoges, Laurent. “Évaluation métrologique de l'étalon primaire de fréquence à
atomes froids de césium FOCS-2.” 2012. Thesis, Université de Neuchâtel. Accessed April 20, 2021.
http://doc.rero.ch/record/30405.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Devenoges, Laurent. “Évaluation métrologique de l'étalon primaire de fréquence à
atomes froids de césium FOCS-2.” 2012. Web. 20 Apr 2021.
Vancouver:
Devenoges L. Évaluation métrologique de l'étalon primaire de fréquence à
atomes froids de césium FOCS-2. [Internet] [Thesis]. Université de Neuchâtel; 2012. [cited 2021 Apr 20].
Available from: http://doc.rero.ch/record/30405.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Devenoges L. Évaluation métrologique de l'étalon primaire de fréquence à
atomes froids de césium FOCS-2. [Thesis]. Université de Neuchâtel; 2012. Available from: http://doc.rero.ch/record/30405
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Université de Neuchâtel
2.
Gharavipour, Mohammadreza.
Ramsey spectroscopy in a Rubidium vapor cell and realization
of an ultra-stable atomic clock.
Degree: 2018, Université de Neuchâtel
URL: http://doc.rero.ch/record/323119
► Divers domaines d’application dans l’industrie, les télécommunications, la navigation et l’espace exigent des étalons de fréquence fiables, compacts et performants avec un niveau de stabilité…
(more)
▼ Divers domaines d’application dans l’industrie, les
télécommunications, la navigation et l’espace exigent des étalons
de fréquence fiables, compacts et performants avec un niveau de
stabilité de <1×10
−14 à
10
5s (équivalent à <1 ns/jour). Avec la
technologie des lasers à semi-conducteurs, la technique du pompage
optique par laser a ouvert de nouveaux schémas d’interrogation
basés sur la double résonance (DR) laser et micro-ondes comme le
pompage optique continu (CW) et le pompage optique pulsé (POP) qui
sont utilisé pour faire de nouvelle horloges atomiques à
cellules. Dans cette thèse, nous présentons les
performances d’un prototype de laboratoire d’horloge atomique à
cellule à vapeur de Rubidium (Rb) fonctionnant avec un schéma
Ramsey-DR (basé sur POP). L’horloge utilise une cavité micro-ondes
compacte de type magnétron avec un volume de seulement 45
cm
3 et un faible facteur de qualité (≈ 150).
Le schéma Ramsey-DR utilise deux champs électromagnétiques
résonants pour interroger les atomes - le champ optique pour
polariser une population d’atomes par pompage optique, et le champ
micro-ondes pour interroger la transition hyperfine de l’état
fondamental qui est la fréquence atomique de référence. Les
impulsions optiques et micro-ondes sont séparées dans le temps dans
le schéma Ramsey-DR ; par conséquent, l’effet de biais de fréquence
du à la lumière (light shift LS) peut être fortement réduit, ce qui
améliore la stabilité de l’horloge. La cavité micro-ondes de type
magnétron est conçue, développée et construite en collaboration
avec le Laboratoire d’Electro- Magnétique et d’Acoustique (LEMA) de
l’Ecole Polytechnique Fédérale de Lausanne
(EPFL)
1. Une cellule de verre nouvellement
fabriquée au LTF avec un volume queusot 10 fois plus petit que la
version précédente est remplie de
87Rb et de
gaz tampon d’Argon et Azote. Un queusot plus petit réduit le
coefficient de température queusot d’environ un ordre de grandeur,
ce qui a été un facteur limitant pour la stabilité de l’horloge à
moyen et long terme. Les caractérisations et performances
détaillées du signal d’horloge (frange centrale du signal Ramsey)
sont présentées dans cette étude
2. Nous
obtenons un signal d’horloge avec un contraste allant jusqu’à
environ 35% et une largeur à mi-hauteur d’environ 160 Hz obtenu en
optimisant les différents paramètres impliqués dans le schéma
Ramsey-DR. Avec notre cavité plus petite, ces réalisations ne sont
pas triviales, car les exigences élevées en matière d’homogénéité
sur l’ensemble du volume de la cellule sont plus difficiles à
satisfaire. Dans cette étude, on obtient une stabilité à court
terme (1 s à 100 s) de
2.4×10
-13<i>τ</i>
−1/2
ce qui est comparable à l’état-de-l’art en utilisant le schéma
CW-DR et/ou en utilisant le schéma POP avec une cavité micro-ondes
TE
011 plus grande avec un facteur de qualité
plus élevé. Le biais de fréquence dû à la lumière (light shift) est
quantifié dans notre horloge atomique Ramsey-DR Rb.…
Advisors/Committee Members: Gaetano (Dir.).
Subjects/Keywords: metrology
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Gharavipour, M. (2018). Ramsey spectroscopy in a Rubidium vapor cell and realization
of an ultra-stable atomic clock. (Thesis). Université de Neuchâtel. Retrieved from http://doc.rero.ch/record/323119
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Gharavipour, Mohammadreza. “Ramsey spectroscopy in a Rubidium vapor cell and realization
of an ultra-stable atomic clock.” 2018. Thesis, Université de Neuchâtel. Accessed April 20, 2021.
http://doc.rero.ch/record/323119.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Gharavipour, Mohammadreza. “Ramsey spectroscopy in a Rubidium vapor cell and realization
of an ultra-stable atomic clock.” 2018. Web. 20 Apr 2021.
Vancouver:
Gharavipour M. Ramsey spectroscopy in a Rubidium vapor cell and realization
of an ultra-stable atomic clock. [Internet] [Thesis]. Université de Neuchâtel; 2018. [cited 2021 Apr 20].
Available from: http://doc.rero.ch/record/323119.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Gharavipour M. Ramsey spectroscopy in a Rubidium vapor cell and realization
of an ultra-stable atomic clock. [Thesis]. Université de Neuchâtel; 2018. Available from: http://doc.rero.ch/record/323119
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Université de Neuchâtel
3.
Bandi, Thejesh N.
Double-resonance studies on compact, high-performance
rubidium cell frequency standards.
Degree: 2013, Université de Neuchâtel
URL: http://doc.rero.ch/record/32317
► This thesis presents experimental studies on continuous-wave (CW) laser-microwave double-resonance (DR) spectroscopy and metrology in rubidium (87Rb) vapor cells in view of new high-performance, compact…
(more)
▼ This thesis presents experimental studies on
continuous-wave (CW) laser-microwave double-resonance (DR)
spectroscopy and
metrology in rubidium (87Rb) vapor cells in view
of new high-performance, compact Rb-cell atomic clocks. The Rb
vapor cell is confined inside a magnetron-type cavity microwave
resonator (MWR). The CW DR spectroscopy involves two resonant
electromagnetic fields that are operated simultaneously to
interrogate the atoms - the <i>optical field</i> to
polarize the atoms by optical pumping, and the <i>microwave
field</i> to drive the ground-state hyperfine clock
transition that serves as an atomic frequency reference. Details on
characterization of compact laser heads and microwave synthesizers
used in this work are presented. The vapor cell standards are
useful in our everyday lives for applications ranging from
telecommunications, navigation,
metrology etc. In view
of improving the performances of the Rb cell standards, two
different clock approaches were studied in detail: The
first one is on use of vapor cells (1.4 cm
3)
whose inner walls are coated with anti-relaxation material. A first
ever wall-coated cell clock was demonstrated with good short-term
frequency stability. The medium- to long-term stability was found
to be limited by the temperature coefficient (TC) of the coating
material itself. This work gave the insight to important features
to be considered in future anti-relaxation coating materials for
atomic standards. The second novel approach involves
using a bigger cell (12 cm
3) within a newly
developed, improved MWR towards a high-performance atomic standard.
Adopting a larger cell gives a higher atomic Q-factor signal that
improves the short-term clock stability. In this approach, the cell
was filled with
87Rb and buffer gases. With
this clock, we demonstrate the state-of-the-art short-term
stability of <1.4×10
−13
<i>τ</i>
−1/2. Metrological
quantitative measurements on parameters influencing the medium- to
long-term stability were studied in view of next generation
satellite navigation systems that demand a stability level of
<1×10
−14 at 10
4 s
(equivalent to <1 ns/day). The potential of short-term stability
and understanding of the limiting factors on medium- to long-term
time scales demonstrated in this study pave the way for future work
towards the commercialization of high-performance Rb atomic clocks
for a variety of applications.
Advisors/Committee Members: Gaetano (Dir.).
Subjects/Keywords: Metrology
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Bandi, T. N. (2013). Double-resonance studies on compact, high-performance
rubidium cell frequency standards. (Thesis). Université de Neuchâtel. Retrieved from http://doc.rero.ch/record/32317
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Bandi, Thejesh N. “Double-resonance studies on compact, high-performance
rubidium cell frequency standards.” 2013. Thesis, Université de Neuchâtel. Accessed April 20, 2021.
http://doc.rero.ch/record/32317.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Bandi, Thejesh N. “Double-resonance studies on compact, high-performance
rubidium cell frequency standards.” 2013. Web. 20 Apr 2021.
Vancouver:
Bandi TN. Double-resonance studies on compact, high-performance
rubidium cell frequency standards. [Internet] [Thesis]. Université de Neuchâtel; 2013. [cited 2021 Apr 20].
Available from: http://doc.rero.ch/record/32317.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Bandi TN. Double-resonance studies on compact, high-performance
rubidium cell frequency standards. [Thesis]. Université de Neuchâtel; 2013. Available from: http://doc.rero.ch/record/32317
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Université de Neuchâtel
4.
Pellaton, Matthieu.
High-resolution spectroscopic studies in glass-blown and
micro-fabricated cells for miniature rubidium atomic clocks.
Degree: 2014, Université de Neuchâtel
URL: http://doc.rero.ch/record/210358
► Les cellules à vapeur d’atomes alcalin et gaz tampon sont au cœur de presque toutes les horloges atomiques commerciales compactes ou miniatures. Elles contiennent une…
(more)
▼ Les cellules à vapeur d’atomes alcalin et gaz tampon
sont au cœur de presque toutes les horloges atomiques commerciales
compactes ou miniatures. Elles contiennent une vapeur d’atomes
alcalin dont une des fréquences de transition atomique sert de
référence stable à l’oscillateur de l’horloge. Ce travail de
recherche porte sur l’étude des phénomènes physiques se déroulant
dans ces cellules et plus particulièrement des effets de
miniaturisation sur la vapeur d’atomes, en vue de la réalisation
d’une horloge miniature. Plus de 150 cellules en verre
soufflé ont été produites et caractérisées, et plus de 30 cellules
micro fabriquées ont été évaluées. Leurs méthodes de fabrications,
ainsi que les évaluations spectroscopiques de certains types
seulement, orientées vers la miniaturisation, sont présentées. Ces
techniques d’évaluation, développées au cours de cette thèse, ont
permis d’évaluer des processus innovants de (micro-) fabrication
développés à Neuchâtel pour des cellules de référence d’horloges
atomiques compactes ou miniatures. Notamment, la caractérisation
par spectroscopie du taux de mélange de gaz tampon avec une
résolution de ±1% ainsi que la détection de fuites aussi petites
que 1.5 x 10
-13 mbar l/s ont permis de
valider deux processus de micro-fabrication de cellule : le
"classique" anodic-bonding ainsi qu’une technique innovante de
scellage à basse température par thermocompression d’indium.
L’utilisation de certains revêtements anti relaxants
permet de s’astreindre du gaz tampon pour la préservation du spin
des atomes; quatre types différents ont été testés: Parylene N et
C, tetracontane et Octadecyl-Trichloro-Silane (OTS). Alors que les
parylenes N et C s’avèrent inadéquats en tant que revêtements
anti-relaxants, d’excellentes propriétés anti-relaxantes sont
obtenues pour le tetracontane, validant ainsi la méthode ainsi que
le système de production développé au LTF pour des cellules en
verre soufflé. La fabrication au sein du LTF a permis l’observation
du phénomène dit de ripening d’une cellule revêtue de tetracontane
par spectroscopie double résonance, dont on présente les résultats.
Une explication physique est également donnée. L’expérience acquise
avec les cellules en verre soufflé a permis la validation
spectroscopique par double résonance d’une cellule micro-fabriquée
avec revêtement OTS. Les résultats sont présentés et les propriétés
antirelaxantes du revêtement sont démontrées pour un volume de
vapeur de rubidium de 4.2 mm
3.
Finalement, une évaluation spectroscopique et métrologique d’un
assemblage "résonateur micro-onde-cellule" novateur et micro
fabriqué d’un volume inférieur à 0.9 cm
3 est
présentée. Le volume de la vapeur de rubidium et de gaz tampon est
de l’ordre de 50 mm
3 seulement. Les
déplacements de fréquence systématiques limitant les performances
métrologiques sont caractérisés, avec une attention particulière
pour le déplacement radiatif. Une analyse détaillée, théorique et
expérimentale, de ce dernier, dans les lignes D1 et D2 et…
Advisors/Committee Members: Gaetano (Dir.).
Subjects/Keywords: metrology
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Pellaton, M. (2014). High-resolution spectroscopic studies in glass-blown and
micro-fabricated cells for miniature rubidium atomic clocks. (Thesis). Université de Neuchâtel. Retrieved from http://doc.rero.ch/record/210358
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Pellaton, Matthieu. “High-resolution spectroscopic studies in glass-blown and
micro-fabricated cells for miniature rubidium atomic clocks.” 2014. Thesis, Université de Neuchâtel. Accessed April 20, 2021.
http://doc.rero.ch/record/210358.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Pellaton, Matthieu. “High-resolution spectroscopic studies in glass-blown and
micro-fabricated cells for miniature rubidium atomic clocks.” 2014. Web. 20 Apr 2021.
Vancouver:
Pellaton M. High-resolution spectroscopic studies in glass-blown and
micro-fabricated cells for miniature rubidium atomic clocks. [Internet] [Thesis]. Université de Neuchâtel; 2014. [cited 2021 Apr 20].
Available from: http://doc.rero.ch/record/210358.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Pellaton M. High-resolution spectroscopic studies in glass-blown and
micro-fabricated cells for miniature rubidium atomic clocks. [Thesis]. Université de Neuchâtel; 2014. Available from: http://doc.rero.ch/record/210358
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of Rochester
5.
Head, Stephen.
Off-null focused beam scatterometry using spatially
varying polarization states.
Degree: PhD, 2018, University of Rochester
URL: http://hdl.handle.net/1802/34294
► The microelectronics industry is driven by advancements which push feature sizes in devices to smaller and smaller scales. Optical scatterometry has filled a niche in…
(more)
▼ The microelectronics industry is driven by
advancements which push feature sizes in devices to smaller and
smaller scales. Optical scatterometry has filled a niche in the
metrology of these devices which concentrates on speed,
repeatability, and low cost. In this thesis, we present, to our
knowledge, the first attempt at the use of spatially-varying input
fields in optimizing the sensitivity of a single shot scatterometry
measurement over many incident angles simultaneously.
We present
initial investigations of polarization generator designs using a
single Spatial Light Modulator (SLM) and discuss the overall layout
of the scatterometry system. We then present the calibration of the
imaging polarimeter, which, along with a Thorlabs PAX5710IR2
polarimeter, is used to investigate calibration and feedback
schemes for the SLM quantitatively.
We present the initial
simulations that guided the project and design of the system, along
with our methods for the simulation of output irradiances for the
output irradiance lookup tables to be used in parameter retrieval.
Lastly, we present experimental results of parameter retrieval
experiments using the simulated lookup table method, subsequent
calibrations of the simulation using input and output polarimetry
measurements, and the challenges associated. The International
Technology Roadmap for Semiconductors claims that parameter
retrieval can be performed through correlation with other methods
which aren't feasible for rapid low cost manufacturing. We present
our interpretation of this method and numerical results with a
comparison of different input fields.
Subjects/Keywords: Metrology; Nanostructure
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Head, S. (2018). Off-null focused beam scatterometry using spatially
varying polarization states. (Doctoral Dissertation). University of Rochester. Retrieved from http://hdl.handle.net/1802/34294
Chicago Manual of Style (16th Edition):
Head, Stephen. “Off-null focused beam scatterometry using spatially
varying polarization states.” 2018. Doctoral Dissertation, University of Rochester. Accessed April 20, 2021.
http://hdl.handle.net/1802/34294.
MLA Handbook (7th Edition):
Head, Stephen. “Off-null focused beam scatterometry using spatially
varying polarization states.” 2018. Web. 20 Apr 2021.
Vancouver:
Head S. Off-null focused beam scatterometry using spatially
varying polarization states. [Internet] [Doctoral dissertation]. University of Rochester; 2018. [cited 2021 Apr 20].
Available from: http://hdl.handle.net/1802/34294.
Council of Science Editors:
Head S. Off-null focused beam scatterometry using spatially
varying polarization states. [Doctoral Dissertation]. University of Rochester; 2018. Available from: http://hdl.handle.net/1802/34294

Baylor University
6.
Herrera, Brandon J., 1986-.
A low-cost embedded network analyzer for the measurement of material properties.
Degree: PhD, Baylor University. Dept. of Electrical & Computer Engineering., 2015, Baylor University
URL: http://hdl.handle.net/2104/9334
► Many industrial processes involve the production of complex composite mixtures of multiple constituents that must be combined according to carefully controlled ratios. Inaccuracies in the…
(more)
▼ Many industrial processes involve the production of complex composite mixtures of multiple constituents that must be combined according to carefully controlled ratios. Inaccuracies in the control of the production processes can lead to out-of-specification mixtures with large variation in quality and properties and possibly an unusable end product. There is a persistent need for a measurement methodology and corresponding practical implementation that is sensitive to the changing constituent ratios having high accuracy and precision that can be used to provide the feedback information required for robust process control. However, the ratios of the individual components in some mixtures can be difficult to measure non-destructively with good accuracy and precision in a real-time, in-line industrial environment. Electromagnetic sensors that provide interrogation of the mixtures over the microwave frequency range have been put forward as a technology class that can meet the in-situ instrumentation requirements for a broad class of scientific and industrial applications. Vector Network Analyzers conveniently make these types of measurements in the scientific laboratory, but their costs are economically prohibitive for industrial applications. To lower instrument costs to a viable price point, a time domain system called a Pulse Dispersion Network Analyzer has been developed for embedded industrial process control of material properties. Several industrial applications are also presented.
Advisors/Committee Members: Jean, B. Randall. (advisor).
Subjects/Keywords: Microwave metrology
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Herrera, Brandon J., 1. (2015). A low-cost embedded network analyzer for the measurement of material properties. (Doctoral Dissertation). Baylor University. Retrieved from http://hdl.handle.net/2104/9334
Chicago Manual of Style (16th Edition):
Herrera, Brandon J., 1986-. “A low-cost embedded network analyzer for the measurement of material properties.” 2015. Doctoral Dissertation, Baylor University. Accessed April 20, 2021.
http://hdl.handle.net/2104/9334.
MLA Handbook (7th Edition):
Herrera, Brandon J., 1986-. “A low-cost embedded network analyzer for the measurement of material properties.” 2015. Web. 20 Apr 2021.
Vancouver:
Herrera, Brandon J. 1. A low-cost embedded network analyzer for the measurement of material properties. [Internet] [Doctoral dissertation]. Baylor University; 2015. [cited 2021 Apr 20].
Available from: http://hdl.handle.net/2104/9334.
Council of Science Editors:
Herrera, Brandon J. 1. A low-cost embedded network analyzer for the measurement of material properties. [Doctoral Dissertation]. Baylor University; 2015. Available from: http://hdl.handle.net/2104/9334

University of Oxford
7.
Warden, Matthew Stuard.
Absolute distance metrology using frequency swept lasers.
Degree: PhD, 2011, University of Oxford
URL: http://ora.ox.ac.uk/objects/uuid:a20e9c69-e580-48d8-bbce-51d8f4186450
;
https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.559856
► This thesis describes and evaluates two new interferometric distance measurement methods based upon the well known method of Frequency Scanning Interferometry (FSI). These new methods…
(more)
▼ This thesis describes and evaluates two new interferometric distance measurement methods based upon the well known method of Frequency Scanning Interferometry (FSI). These new methods are known as Dynamic FSI and Cascaded FSI. Dynamic FSI addresses the two problems, commonly seen in previous FSI implementa- tions, of not being able to measure a moving target and having a slow measurement rate. This method measures stationary and moving targets equally well, and can determine the distance to the target at all times during the measurement, in contrast to previous methods, which obtain only a single measured length from a measurement process which can take up to a second to make. Cascaded FSI was developed with the aim of increasing the accuracy and precision of FSI. This method allows for measurements with precision equal to that of displacement interferometry, and also provides a way of measuring length relative to the frequencies of atomic absorption lines, which are inherently more stable length references than a physical length artefact.
Subjects/Keywords: 389.1; Physics; interferometry; metrology; dimensional metrology
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APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Warden, M. S. (2011). Absolute distance metrology using frequency swept lasers. (Doctoral Dissertation). University of Oxford. Retrieved from http://ora.ox.ac.uk/objects/uuid:a20e9c69-e580-48d8-bbce-51d8f4186450 ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.559856
Chicago Manual of Style (16th Edition):
Warden, Matthew Stuard. “Absolute distance metrology using frequency swept lasers.” 2011. Doctoral Dissertation, University of Oxford. Accessed April 20, 2021.
http://ora.ox.ac.uk/objects/uuid:a20e9c69-e580-48d8-bbce-51d8f4186450 ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.559856.
MLA Handbook (7th Edition):
Warden, Matthew Stuard. “Absolute distance metrology using frequency swept lasers.” 2011. Web. 20 Apr 2021.
Vancouver:
Warden MS. Absolute distance metrology using frequency swept lasers. [Internet] [Doctoral dissertation]. University of Oxford; 2011. [cited 2021 Apr 20].
Available from: http://ora.ox.ac.uk/objects/uuid:a20e9c69-e580-48d8-bbce-51d8f4186450 ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.559856.
Council of Science Editors:
Warden MS. Absolute distance metrology using frequency swept lasers. [Doctoral Dissertation]. University of Oxford; 2011. Available from: http://ora.ox.ac.uk/objects/uuid:a20e9c69-e580-48d8-bbce-51d8f4186450 ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.559856

University of Nairobi
8.
Njihia, Florence W.
Challenges facing the use of technology on legal metrology :The case of Meru municipality,Kenya
.
Degree: 2012, University of Nairobi
URL: http://erepository.uonbi.ac.ke:8080/xmlui/handle/123456789/11114
► The study will be investigating the challenges facing the use of technology in legal metrology, the case of Meru municipality, Kenya. The study will be…
(more)
▼ The study will be investigating the challenges facing the use of technology in legal metrology,
the case of Meru municipality, Kenya. The study will be guided by the following objectives: To
establish the influence of cost of digital/electronic weighing and measuring instruments on legal
metrology; to assess the influence of operation of electronic weighing and measuring
instruments on legal metrology; to establish the extent to which technical know-how and
training on electronic weighing and measuring instruments influence legal metrology; to
establish how standardization of electronic weighing and measuring instruments influence legal
metrology. The study will target traders, weights and measures officers, licensed weights and
measures repairers in Meru region from Meru Municipality. The researcher will use stratified
random sampling procedure and then adopt descriptive research design. The data will be
gathered from the traders in Meru, weights and measures Officers in Meru region and of Meru
Municipality, through questionnaires structured on the basis of the objectives of this study. Data
required for analysis will be collected from the respondents and analyzed using Statistical
Packages for Social Service. The findings of the study will be significant to the Government of
Kenya, various stakeholders, weights and measures department staff of Meru Municipality.
Subjects/Keywords: Technology;
Legal metrology
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APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Njihia, F. W. (2012). Challenges facing the use of technology on legal metrology :The case of Meru municipality,Kenya
. (Thesis). University of Nairobi. Retrieved from http://erepository.uonbi.ac.ke:8080/xmlui/handle/123456789/11114
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Njihia, Florence W. “Challenges facing the use of technology on legal metrology :The case of Meru municipality,Kenya
.” 2012. Thesis, University of Nairobi. Accessed April 20, 2021.
http://erepository.uonbi.ac.ke:8080/xmlui/handle/123456789/11114.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Njihia, Florence W. “Challenges facing the use of technology on legal metrology :The case of Meru municipality,Kenya
.” 2012. Web. 20 Apr 2021.
Vancouver:
Njihia FW. Challenges facing the use of technology on legal metrology :The case of Meru municipality,Kenya
. [Internet] [Thesis]. University of Nairobi; 2012. [cited 2021 Apr 20].
Available from: http://erepository.uonbi.ac.ke:8080/xmlui/handle/123456789/11114.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Njihia FW. Challenges facing the use of technology on legal metrology :The case of Meru municipality,Kenya
. [Thesis]. University of Nairobi; 2012. Available from: http://erepository.uonbi.ac.ke:8080/xmlui/handle/123456789/11114
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of Arizona
9.
Tian, Xiaobo.
Snapshot Interferometric Systems with Polarization Cameras
.
Degree: 2020, University of Arizona
URL: http://hdl.handle.net/10150/641721
► Interferometry has been established as an important tool for a variety of applications, including physics, industrial manufacturing, biology, and medicine. Phase-shifting interferometry is one of…
(more)
▼ Interferometry has been established as an important tool for a variety of applications, including physics, industrial manufacturing, biology, and medicine. Phase-shifting interferometry is one of the most general methods in interferometric systems for its high measurement accuracy, rapid measurement, good results for low contrast fringes, and independence of irradiance variations across the pupil. In most cases, the phase calculation error caused by environmental noise is the primary error. Comparing with temporal phase-shifting, which introduces a phase-shift sequentially, spatial phase-shifting methods that capture phase-shifted interferograms simultaneously can significantly reduce the influence of environmental noise.
In this dissertation, we present several snapshot phase-shifting interferometric systems with the pixelated mask spatial phase-shifting technique using a polarization camera. As a spatial phase-shifting method, the pixelated polarization camera method has the advantages of a common path configuration, compact design, achromatic over a very wide range, and fixed spatial interference patterns, which makes it suitable for dynamic measurement. Various applications based on this technique are presented, including on-machine interferometry, single-shot multi-wavelength interferometry, snapshot quantitative phase microscopy, and freeform surface
metrology. The principles and applications are theoretical analyzed and experimental demonstrated for each system.
Advisors/Committee Members: Liang, Rongguang (advisor), Pau, Stanley (committeemember), Kim, Daewook (committeemember).
Subjects/Keywords: Interferometry;
Metrology;
Polarization
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Tian, X. (2020). Snapshot Interferometric Systems with Polarization Cameras
. (Doctoral Dissertation). University of Arizona. Retrieved from http://hdl.handle.net/10150/641721
Chicago Manual of Style (16th Edition):
Tian, Xiaobo. “Snapshot Interferometric Systems with Polarization Cameras
.” 2020. Doctoral Dissertation, University of Arizona. Accessed April 20, 2021.
http://hdl.handle.net/10150/641721.
MLA Handbook (7th Edition):
Tian, Xiaobo. “Snapshot Interferometric Systems with Polarization Cameras
.” 2020. Web. 20 Apr 2021.
Vancouver:
Tian X. Snapshot Interferometric Systems with Polarization Cameras
. [Internet] [Doctoral dissertation]. University of Arizona; 2020. [cited 2021 Apr 20].
Available from: http://hdl.handle.net/10150/641721.
Council of Science Editors:
Tian X. Snapshot Interferometric Systems with Polarization Cameras
. [Doctoral Dissertation]. University of Arizona; 2020. Available from: http://hdl.handle.net/10150/641721

University of Manchester
10.
Barnfather, Joshua.
Metrology assisted robotic feature machining on large nuclear power plant components.
Degree: PhD, 2018, University of Manchester
URL: https://www.research.manchester.ac.uk/portal/en/theses/metrology-assisted-robotic-feature-machining-on-large-nuclear-power-plant-components(34de00c8-0d7c-4b99-8680-cbd5061ceeb4).html
;
https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.779633
► The scale of large nuclear power plant components makes the setup and operation of manufacturing facilities producing them highly capital intensive. An alternative approach is…
(more)
▼ The scale of large nuclear power plant components makes the setup and operation of manufacturing facilities producing them highly capital intensive. An alternative approach is flexible, process-to-part robotic feature machining, which has a low capital expenditure, reduces heavy lifting requirements and takes up less permanent floorspace. A barrier to adopting robotic machine tools is that they are unable to achieve the tolerances of conventional machines tools. This thesis therefore investigates the idea that, although various levels of dimensional error accumulate in robotic machined features for complex reasons, errors are predominantly systematic and can be measured using efficient, non-contact techniques and compensated in-situ with the machining process. This represents a significant gap in the literature. An initial cost benefit analysis also finds that robotic machining could allow costs and equipment payback periods to be reduced by 76% and 69%, respectively. To validate compensation feasibility, errors are characterised using a candidate robotic machine tool. This is initially done by developing a robust robotic machining performance evaluation methodology, which makes a contribution by filling a significant gaps in robotics and machine tool standards. This guides experimental work investigating positional and machining error in a varied range of robotic feature machining operations. Results confirm that robot errors, in non-cutting and cutting conditions, are highly variable but predominantly systematic and potentially correctable. Robot error is found to be subject to the greatest degree of variance according to geometry, i.e. robot position and therefore machined feature form. This work fills a gap in the literature by thoroughly quantifying how all the complex contributors to robotic machining error relate to achievable tolerances, advancing the state of the art by providing a benchmark for judging general developments against. To solve challenges, an algorithm to compensate machining trajectories with in-situ non-contact dimensional error measurements on robot machined features was developed and tested. Simulations show that the proposed solution is successful. During practical experimentation, barriers are found and quantified relating to uneven point cloud coverage and noise. This work informs further algorithm optimisation and makes a contribution to the state of the art of robotic machining error compensation by considering total dimensional error compensation, without focus on individual error contributors, by densely measuring errors across robotic machined parts directly to account for their varying nature. Measurement challenges for compensation are investigated in depth, providing insight that is not thoroughly documented in the literature. Results quantify problems with noise, point coverage and geometrical variance. Compensation algorithm performance is then optimised by investigating a novel, efficient approach that restricts error measurement to a single direction and then smooths the…
Subjects/Keywords: Metrology; Robotics; Manufacturing
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Barnfather, J. (2018). Metrology assisted robotic feature machining on large nuclear power plant components. (Doctoral Dissertation). University of Manchester. Retrieved from https://www.research.manchester.ac.uk/portal/en/theses/metrology-assisted-robotic-feature-machining-on-large-nuclear-power-plant-components(34de00c8-0d7c-4b99-8680-cbd5061ceeb4).html ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.779633
Chicago Manual of Style (16th Edition):
Barnfather, Joshua. “Metrology assisted robotic feature machining on large nuclear power plant components.” 2018. Doctoral Dissertation, University of Manchester. Accessed April 20, 2021.
https://www.research.manchester.ac.uk/portal/en/theses/metrology-assisted-robotic-feature-machining-on-large-nuclear-power-plant-components(34de00c8-0d7c-4b99-8680-cbd5061ceeb4).html ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.779633.
MLA Handbook (7th Edition):
Barnfather, Joshua. “Metrology assisted robotic feature machining on large nuclear power plant components.” 2018. Web. 20 Apr 2021.
Vancouver:
Barnfather J. Metrology assisted robotic feature machining on large nuclear power plant components. [Internet] [Doctoral dissertation]. University of Manchester; 2018. [cited 2021 Apr 20].
Available from: https://www.research.manchester.ac.uk/portal/en/theses/metrology-assisted-robotic-feature-machining-on-large-nuclear-power-plant-components(34de00c8-0d7c-4b99-8680-cbd5061ceeb4).html ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.779633.
Council of Science Editors:
Barnfather J. Metrology assisted robotic feature machining on large nuclear power plant components. [Doctoral Dissertation]. University of Manchester; 2018. Available from: https://www.research.manchester.ac.uk/portal/en/theses/metrology-assisted-robotic-feature-machining-on-large-nuclear-power-plant-components(34de00c8-0d7c-4b99-8680-cbd5061ceeb4).html ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.779633
11.
Hemming, Björn.
Measurement Traceability and Uncertainty in Machine Vision Applications.
Degree: 2008, Helsinki University of Technology
URL: http://lib.tkk.fi/Diss/2007/isbn9789525610413/
► During the past decades increasing use of machine vision in dimensional measurements has been seen. From a metrological view every serious measurement should be traceable…
(more)
▼ During the past decades increasing use of machine vision in dimensional measurements has been seen. From a metrological view every serious measurement should be traceable to SI units and have a stated measurement uncertainty. The first step to ensure this is the calibration of the measurement instruments. Quality systems in manufacturing industry require traceable calibrations and measurements. This has lead to a good knowledge of measurement accuracy for traditional manual hand-held measurement instruments. The entrance of rather complex computerised machine vision instruments and optical coordinate measuring machines, at the production lines and measurement rooms, is a threat or at least a challenge, to the understanding of the accuracy of the measurement. Accuracies of algorithms for edge detection and camera calibration are studied in the field of machine vision, but uncertainty evaluations of complete systems are seldom seen. In real applications the final measurement uncertainty is affected by many factors such as illumination, edge effects, the operator, and non-idealities of the object to be measured. In this thesis the use of the GUM (Guide to the Expression of Uncertainty in Measurement) method is applied for the estimation of measurement uncertainty in two machine vision applications. The work is mainly limited to two-dimensional applications where a gray-scale camera is used. The described equipment for calibration of micrometers using machine vision is unique. The full evaluation of measurement uncertainty in aperture diameter measurements using an optical coordinate measuring machine is presented for the first time. In the presented applications the uncertainty budgets are very different. This confirms the conclusion, that a detailed uncertainty budget is the only way to achieve an understanding of the reliability of dimensional measurements in machine vision. Uncertainty budgets for the type of the two described machine vision applications have never previously been published.
Viime vuosikymmenien aikana konenäkö on yleistynyt yhä enemmän geometrisissä mittauksissa. Metrologisesta näkökulmasta jokaisen mittauksen olisi oltava jäljitettävissä SI-yksikköjärjestelmään ja jokaisella mittauksella tulisi olla tunnettu mittausepävarmuus. Kaupallisesta näkökulmasta on tärkeää, että tavaran mitattavista ominaisuuksista ei synny mittausvirheistä johtuvia kiistoja ostajan ja myyjän välillä. Jos mittausepävarmuus on tunnettu, niin kalibroinnilla saadaan aikaan jäljitettävyys perussuureeseen. Jäljitettävyys konenäkösovelluksissa pituuden SI-yksikköön metriin saadaan aikaan pitkällä katkeamattomalla jäljitettävyysketjulla. Konepajoissa laatujärjestelmät ovat jo pitkään edellyttäneet, että mittalaitteet ovat jäljitettävästi kalibroitu. Jokaiseen kalibrointiin liittyy myös mittausepävarmuuslaskelma, jossa tärkeimmät epävarmuuslähteet ovat mallinnettu. Optisten koordinaattimittauskoneiden sekä muiden konenäköön perustuvien mittausjärjestelmien mutkikkuus on suuri haaste mittausepävarmuuslaskelman laatimiselle.…
Advisors/Committee Members: Helsinki University of Technology, Department of Electrical and Communications Engineering, MIKES Metrology Research Institute.
Subjects/Keywords: metrology; reference standards; CCD camera
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Hemming, B. (2008). Measurement Traceability and Uncertainty in Machine Vision Applications. (Thesis). Helsinki University of Technology. Retrieved from http://lib.tkk.fi/Diss/2007/isbn9789525610413/
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Hemming, Björn. “Measurement Traceability and Uncertainty in Machine Vision Applications.” 2008. Thesis, Helsinki University of Technology. Accessed April 20, 2021.
http://lib.tkk.fi/Diss/2007/isbn9789525610413/.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Hemming, Björn. “Measurement Traceability and Uncertainty in Machine Vision Applications.” 2008. Web. 20 Apr 2021.
Vancouver:
Hemming B. Measurement Traceability and Uncertainty in Machine Vision Applications. [Internet] [Thesis]. Helsinki University of Technology; 2008. [cited 2021 Apr 20].
Available from: http://lib.tkk.fi/Diss/2007/isbn9789525610413/.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Hemming B. Measurement Traceability and Uncertainty in Machine Vision Applications. [Thesis]. Helsinki University of Technology; 2008. Available from: http://lib.tkk.fi/Diss/2007/isbn9789525610413/
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University College London (University of London)
12.
Patel, Ketan Shantilal.
Vibro-spring particle size distribution analyser.
Degree: PhD, 2001, University College London (University of London)
URL: https://discovery.ucl.ac.uk/id/eprint/10098822/
;
https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.252097
► This thesis describes the design and development of a fully automated pre-production particle size distribution analyser for dry powders in the 30 - 2000 μm…
(more)
▼ This thesis describes the design and development of a fully automated pre-production particle size distribution analyser for dry powders in the 30 - 2000 μm size range. In its most basic form, the instrument comprises a horizontally held closed coil helical spring partly filled with the test powder that is mounted at one end of a double beam cantilever system pivoted along its length. Particle size distribution data are obtained by stretching the spring to known lengths and measuring the mass of the powder discharged from the spring's coils following transverse vibration at resonance. The size of the particles on the other hand is determined from the spring 'intercoir distance. The main thrust of the thesis describes the developments of the appropriate technology and methodology for in-situ and continuos measurement of the mass of the powder within the spring and system automation. Two distinct methods were developed in order to measure sample mass. The first deceptively simple approach involved mass determination from the vibration characteristics of the spring and the supporting structure during resonance vibration. This approach was unsuccessful as it was found that apart from the sample mass, the vibration characteristics were also a strong and complicated function of spring tension. The second and far more successful technique involved a two-stage dynamic-static operation in which particulate discharge is followed by wanton termination of vibration. The sample mass is then measured by monitoring the deflection of the cantilever system about its main axis. In this way, for a typical charge sample of 10 g, discharge mass may be measured with a combined resolution and reproducibility of ca. 0.1 g. The corresponding size resolution is ca. 5 μm. Particle size distribution data relating to the performance evaluation of the system are reported in conjunction with a variety of powders differing in size and shape including ballotini, milk powder, grit stone, sawdust, clay and sand. System automation has involved work on both the mechanical and computer control aspects. The former required the developments of a specially designed non-contact gear mechanism for accurate extension of the spring to predetermined lengths as well as an automated particulate pneumatic feed system. The computerised features of the instrument include fully automated operation such as data acquisition, manipulation and display.
Subjects/Keywords: 530; Metrology
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Patel, K. S. (2001). Vibro-spring particle size distribution analyser. (Doctoral Dissertation). University College London (University of London). Retrieved from https://discovery.ucl.ac.uk/id/eprint/10098822/ ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.252097
Chicago Manual of Style (16th Edition):
Patel, Ketan Shantilal. “Vibro-spring particle size distribution analyser.” 2001. Doctoral Dissertation, University College London (University of London). Accessed April 20, 2021.
https://discovery.ucl.ac.uk/id/eprint/10098822/ ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.252097.
MLA Handbook (7th Edition):
Patel, Ketan Shantilal. “Vibro-spring particle size distribution analyser.” 2001. Web. 20 Apr 2021.
Vancouver:
Patel KS. Vibro-spring particle size distribution analyser. [Internet] [Doctoral dissertation]. University College London (University of London); 2001. [cited 2021 Apr 20].
Available from: https://discovery.ucl.ac.uk/id/eprint/10098822/ ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.252097.
Council of Science Editors:
Patel KS. Vibro-spring particle size distribution analyser. [Doctoral Dissertation]. University College London (University of London); 2001. Available from: https://discovery.ucl.ac.uk/id/eprint/10098822/ ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.252097

Nanyang Technological University
13.
Huang, Lei.
Advances in 3D optical profilometry
.
Degree: 2013, Nanyang Technological University
URL: http://hdl.handle.net/10356/52124
► The increased significance and need for three-dimensional (3D) shape measurement in various industries for 3D inspection, quality control, and reverse engineering, has promoted the interest…
(more)
▼ The increased significance and need for three-dimensional (3D) shape measurement in various industries for 3D inspection, quality control, and reverse engineering, has promoted the interest in 3D metrology. Among the 3D shape measurement techniques, optical methods show great advantages by offering non-contact, fast and flexible measurement systems compared to tactile tools such as the ubiquitous Coordinate Measuring Machine (CMM). However, various challenges still need to be addressed as the needs for accuracy, robustness, speed, and reliability increase.
Basically 3D optical metrology has the following components – a pattern (fringe) illumination module, interaction of the fringe pattern with the object under test, recording of the fringe pattern using a digital camera (imaging module), and finally processing of the recorded results followed by display of the results. There are three types of surfaces – diffuse, specular, and transparent surfaces – typically encountered in engineering objects. The illumination, sample and imaging modules are treated as an entire system and combined effects are considered in the processing and data reduction stages. However, the phase which is obtained from the fringe processing is related to the profile in different ways for each of the methods.
Fringe processing is one of the key aspects in optical 3D metrology. In the derivation of phase shift equations, a sinusoidal profile is presumed. Practically this is not always true and a novel scheme to analyze and compensate phase error from non-sinusoidal waveforms is proposed. Phase error is compensated through an iterative process based on analysis of the theoretical phase error. Experimental results demonstrate the feasibility of the proposed compensation method in removal of the periodical phase error due to the non-sinusoidal waveform. In addition, a practical phase retrieval framework is proposed for multi-frequency phase shifting method to accurately calculate the absolute phase and automatically identify invalid phase points via a thresholding and criterion checking process. For dynamic application, only a single frame of data is available to retrieve the wrapped phase and then unwrap it. A comparison of the transform-based algorithms for single-frame phase retrieval is conducted in the presence of noise and non-sinusoidal waveform conditions with simulation and experiment. The methods of 2D Windowed Fourier Ridges and 2D Wavelet Transform are the two superior phase retrieval algorithms in fringe projection profilometry. Quality-guided phase unwrapping technique is reviewed with a comparison on quality definitions and guiding strategies. When unwrapping noisy phase, transform-based methods perform better but with increased computation time. But none of the quality maps always succeeds in handling phase discontinuities. For guiding strategies, the classical guiding strategy with a data structure of indexed interwoven linked list is fastest to achieve the most reasonable unwrapping results. If a small unwrapping…
Subjects/Keywords: DRNTU::Engineering::Manufacturing::Metrology
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Huang, L. (2013). Advances in 3D optical profilometry
. (Thesis). Nanyang Technological University. Retrieved from http://hdl.handle.net/10356/52124
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Huang, Lei. “Advances in 3D optical profilometry
.” 2013. Thesis, Nanyang Technological University. Accessed April 20, 2021.
http://hdl.handle.net/10356/52124.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Huang, Lei. “Advances in 3D optical profilometry
.” 2013. Web. 20 Apr 2021.
Vancouver:
Huang L. Advances in 3D optical profilometry
. [Internet] [Thesis]. Nanyang Technological University; 2013. [cited 2021 Apr 20].
Available from: http://hdl.handle.net/10356/52124.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Huang L. Advances in 3D optical profilometry
. [Thesis]. Nanyang Technological University; 2013. Available from: http://hdl.handle.net/10356/52124
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Brunel University
14.
MacAulay, Gavin.
Characterisation of structured surfaces and assessment of associated measurement uncertainty.
Degree: PhD, 2016, Brunel University
URL: http://bura.brunel.ac.uk/handle/2438/13473
;
http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.699278
► Recently, structured surfaces, consisting of deterministic features designed to produce a particular effect, have shown promise in providing superior functional performance for a range of…
(more)
▼ Recently, structured surfaces, consisting of deterministic features designed to produce a particular effect, have shown promise in providing superior functional performance for a range of applications including: low friction surfaces, hydrophobic surfaces and optical effects. Methods have been developed to characterise such structured surfaces. The most widely used characterisation methods are based on segmenting the surface in feature and background regions and then determining the geometrical properties of those features. However, further work is needed to refine these characterisation techniques and provide associated uncertainties. This thesis considers the effect of various segmentation control parameters such as thresholds on the final geometric parameters. The effect of varying filter size is also considered. These considerations should help in selecting a suitable characterisation method for future projects. Additionally, uncertainty in the characterisation should be estimated in order to give an indication of the accuracy of the assessment. However, no previous work has assessed uncertainty in the dimensional properties of structured surfaces. Therefore, this thesis presents two methods to characterise the uncertainty in the geometric characteristics of structured surfaces. First, the measurement reproducibility is used, which can be determined by repeated measurement of a feature. However, measurement reproducibility cannot account for all sources of uncertainty and cannot assess any bias in the measurements. Therefore, a second method based on assessment of the metrological characteristics of the instrument is considered. The metrological characteristics estimate errors produced by the instrument in a way that can easily be measured. Monte Carlo techniques are then used to propagate the effects of the metrological characteristics and their uncertainties into the final measurement uncertainty. For the example used, it was found that the results using the metrological characteristics were in good agreement with the reproducibility results. From these results, it is concluded that the choice of segmentation method, control parameters and filtering can all significantly effect the characterisation of features on a structured surface, often in unexpected ways. Therefore, care must be taken when selecting these values for a specific application. Additionally, two methods of determining the uncertainty of the structured surfaces were considered. Both methods are valid and produce similar results. Using the measurement reproducibility is simple to perform, but requires many measurements and cannot account for some uncertainty sources such as those due to the instrument amplification factors. On the other hand, the use of metrological characteristics can account for all significant sources of uncertainty in a measurement, but is mathematically more complex, requiring Monte Carlo simulations to propagate the uncertainties into the final characteristics. Additionally, other artefacts than the sample being measured…
Subjects/Keywords: 620; Structured surfaces; Metrology; Uncertainty
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APA (6th Edition):
MacAulay, G. (2016). Characterisation of structured surfaces and assessment of associated measurement uncertainty. (Doctoral Dissertation). Brunel University. Retrieved from http://bura.brunel.ac.uk/handle/2438/13473 ; http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.699278
Chicago Manual of Style (16th Edition):
MacAulay, Gavin. “Characterisation of structured surfaces and assessment of associated measurement uncertainty.” 2016. Doctoral Dissertation, Brunel University. Accessed April 20, 2021.
http://bura.brunel.ac.uk/handle/2438/13473 ; http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.699278.
MLA Handbook (7th Edition):
MacAulay, Gavin. “Characterisation of structured surfaces and assessment of associated measurement uncertainty.” 2016. Web. 20 Apr 2021.
Vancouver:
MacAulay G. Characterisation of structured surfaces and assessment of associated measurement uncertainty. [Internet] [Doctoral dissertation]. Brunel University; 2016. [cited 2021 Apr 20].
Available from: http://bura.brunel.ac.uk/handle/2438/13473 ; http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.699278.
Council of Science Editors:
MacAulay G. Characterisation of structured surfaces and assessment of associated measurement uncertainty. [Doctoral Dissertation]. Brunel University; 2016. Available from: http://bura.brunel.ac.uk/handle/2438/13473 ; http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.699278

University of Surrey
15.
Jenkins, Stephen Neil.
The development and application of a Transmission X-ray Photoelectron Spectrometer (TXPS).
Degree: PhD, 1993, University of Surrey
URL: http://epubs.surrey.ac.uk/843902/
;
https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.385098
► There is a growing demand to obtain XPS analyses from increasingly smaller sample areas. The development of a Transmission X-Ray Photoelectron Spectrometer (TXPS) will allow…
(more)
▼ There is a growing demand to obtain XPS analyses from increasingly smaller sample areas. The development of a Transmission X-Ray Photoelectron Spectrometer (TXPS) will allow spectrum acquisition and imaging with a lateral resolution approaching 1 mum2. The principle is based on back-foil excitation where thin samples are placed on an aluminium foil or have an evaporated source backing. Electron irradiation of the foil produces characteristic X-rays locally and this, in turn, gives rise to a small source of photoelectrons from the opposite side of the sample. Rastering the electron beam scans the X-ray interaction volume which allows imaging. Photoelectron lateral resolution is dependent on the sample and foil thicknesses and is determined by the width of the X-ray excitation envelope and on the electron beam diameter. In this work a VG Scientific MA500 is modified to give the ideal 180° geometry for TXPS. A hemispherical analyser with an extended high magnification transfer lens ensures a large solid angle of photoelectron collection, and the hemispherical analyser gives the (previously unobtainable) energy resolution necessary to obtain chemical state information. Aspects unique to TXPS spectral and image interpretation are described. The analysis conditions where sample damage is likely are investigated. Photon induced damage is manageable, but is shown to be far more of a technique drawback than Joule heating. Specimen charging presents no particular problems, although it can be both positive and negative in TXPS. It is believed that TXPS is the ideal way of examining ultramicrotomed sections through interfaces and soft composite materials. Harder materials, such as ceramics and metals, require ion beam thinning in a similar way to TEM specimens. Specimen production needs are addressed as well as the problem of making the TXPS technique far more routine to the analyst. A magnesium/aluminium alloy is ion beam thinned to demonstrate TXPS from a harder material. The interlayer between a chlorine containing latex and mild steel is also analysed by TXPS, following the removal of the bulk substrate and ultramicrotomy. Data are examined and an iron valence state change across the interface allows conclusions to be drawn about the continued growth of the protective interphase under environmental exposure.
Subjects/Keywords: 530.8; Metrology
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APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
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APA (6th Edition):
Jenkins, S. N. (1993). The development and application of a Transmission X-ray Photoelectron Spectrometer (TXPS). (Doctoral Dissertation). University of Surrey. Retrieved from http://epubs.surrey.ac.uk/843902/ ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.385098
Chicago Manual of Style (16th Edition):
Jenkins, Stephen Neil. “The development and application of a Transmission X-ray Photoelectron Spectrometer (TXPS).” 1993. Doctoral Dissertation, University of Surrey. Accessed April 20, 2021.
http://epubs.surrey.ac.uk/843902/ ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.385098.
MLA Handbook (7th Edition):
Jenkins, Stephen Neil. “The development and application of a Transmission X-ray Photoelectron Spectrometer (TXPS).” 1993. Web. 20 Apr 2021.
Vancouver:
Jenkins SN. The development and application of a Transmission X-ray Photoelectron Spectrometer (TXPS). [Internet] [Doctoral dissertation]. University of Surrey; 1993. [cited 2021 Apr 20].
Available from: http://epubs.surrey.ac.uk/843902/ ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.385098.
Council of Science Editors:
Jenkins SN. The development and application of a Transmission X-ray Photoelectron Spectrometer (TXPS). [Doctoral Dissertation]. University of Surrey; 1993. Available from: http://epubs.surrey.ac.uk/843902/ ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.385098

University of Bath
16.
Martin, Oliver.
Metrology enabled tooling for the assembly of aero-structures.
Degree: PhD, 2016, University of Bath
URL: https://researchportal.bath.ac.uk/en/studentthesis/metrology-enabled-tooling-for-the-assembly-of-aerostructures(3c782a3e-9259-49aa-82e4-b58324843a47).html
;
https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.690722
► Metrology and Tooling are considered as discrete disciplines within Manufacturing Engineering, however, assembly tooling often acts as a checking mechanism. Assembly tooling has the primary…
(more)
▼ Metrology and Tooling are considered as discrete disciplines within Manufacturing Engineering, however, assembly tooling often acts as a checking mechanism. Assembly tooling has the primary function of controlling part location during assembly; with a secondary requirement as a quality gate. In-tool checks are manual mechanical checks of the assembly, these gauging checks assume the tooling has the correct, nominal geometry. Tooling conformance is certified periodically; however these intervals can be up to three years. Further examination of the metrology requirements within the aerospace industry with respect to large scale assembly tooling identify a requirement to: reduce manual metrology checks, reduce tooling recertification time, and enable greater automation. Currently, there is a lack of integration between metrology and Wing-box assembly tooling. This research investigates how to increase manufacturing confidence with respect to tooling conformance; and, ultimately improve the manufacturing process for aero-structures, through the increased and enhanced use of metrology in the assembly tooling environment. The Metrology Enhanced Tooling for Aerospace (META) framework has been created to provide a robust framework for deploying metrology in the tooling environment. The major elements of the framework are subsequently detailed and demonstrated in three chapters: i) large volume metrology networks, for the measurement of tooling structures; testing instrument performance, quantifying and improving the uncertainty estimation, and ultimately, establishing a rapid measurement process for assembly tooling; ii) embedded metrology systems demonstrates how local measurement systems can be utilised to replace and improve on, traditional in-tool checks; and iii) metrology feedback presents an example of an automated tooling pick-up that manipulates the assembly to achieve the design intent. The contributions can be summarised as: firstly, the creation of the META framework for the deployment of metrology in assembly tooling environment, accommodating and facilitating a number of the future tooling and assembly requirements. Secondly, the establishment of a generic commissioning methodology and measurement strategy for the rapid measurement of assembly tooling to increase tooling confidence. The research output was demonstrated in a case study, through a combination of physical measurement and digital automation simulation to prove the process time was greatly decreased from current methods.
Subjects/Keywords: 629.1; Metrology; Tooling; Aerospace
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Martin, O. (2016). Metrology enabled tooling for the assembly of aero-structures. (Doctoral Dissertation). University of Bath. Retrieved from https://researchportal.bath.ac.uk/en/studentthesis/metrology-enabled-tooling-for-the-assembly-of-aerostructures(3c782a3e-9259-49aa-82e4-b58324843a47).html ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.690722
Chicago Manual of Style (16th Edition):
Martin, Oliver. “Metrology enabled tooling for the assembly of aero-structures.” 2016. Doctoral Dissertation, University of Bath. Accessed April 20, 2021.
https://researchportal.bath.ac.uk/en/studentthesis/metrology-enabled-tooling-for-the-assembly-of-aerostructures(3c782a3e-9259-49aa-82e4-b58324843a47).html ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.690722.
MLA Handbook (7th Edition):
Martin, Oliver. “Metrology enabled tooling for the assembly of aero-structures.” 2016. Web. 20 Apr 2021.
Vancouver:
Martin O. Metrology enabled tooling for the assembly of aero-structures. [Internet] [Doctoral dissertation]. University of Bath; 2016. [cited 2021 Apr 20].
Available from: https://researchportal.bath.ac.uk/en/studentthesis/metrology-enabled-tooling-for-the-assembly-of-aerostructures(3c782a3e-9259-49aa-82e4-b58324843a47).html ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.690722.
Council of Science Editors:
Martin O. Metrology enabled tooling for the assembly of aero-structures. [Doctoral Dissertation]. University of Bath; 2016. Available from: https://researchportal.bath.ac.uk/en/studentthesis/metrology-enabled-tooling-for-the-assembly-of-aerostructures(3c782a3e-9259-49aa-82e4-b58324843a47).html ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.690722

University of York
17.
Chew, Andrew David.
A rotating disc gauge for absolute total pressure measurement in a high vacuum.
Degree: PhD, 1993, University of York
URL: http://etheses.whiterose.ac.uk/10874/
;
http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.317722
Subjects/Keywords: 530.8; Metrology
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APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
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APA (6th Edition):
Chew, A. D. (1993). A rotating disc gauge for absolute total pressure measurement in a high vacuum. (Doctoral Dissertation). University of York. Retrieved from http://etheses.whiterose.ac.uk/10874/ ; http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.317722
Chicago Manual of Style (16th Edition):
Chew, Andrew David. “A rotating disc gauge for absolute total pressure measurement in a high vacuum.” 1993. Doctoral Dissertation, University of York. Accessed April 20, 2021.
http://etheses.whiterose.ac.uk/10874/ ; http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.317722.
MLA Handbook (7th Edition):
Chew, Andrew David. “A rotating disc gauge for absolute total pressure measurement in a high vacuum.” 1993. Web. 20 Apr 2021.
Vancouver:
Chew AD. A rotating disc gauge for absolute total pressure measurement in a high vacuum. [Internet] [Doctoral dissertation]. University of York; 1993. [cited 2021 Apr 20].
Available from: http://etheses.whiterose.ac.uk/10874/ ; http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.317722.
Council of Science Editors:
Chew AD. A rotating disc gauge for absolute total pressure measurement in a high vacuum. [Doctoral Dissertation]. University of York; 1993. Available from: http://etheses.whiterose.ac.uk/10874/ ; http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.317722

Brunel University
18.
Jaturunruangsri, Supaporn.
Evaluation of material surface profiling methods : contact versus non-contact.
Degree: PhD, 2015, Brunel University
URL: http://bura.brunel.ac.uk/handle/2438/10431
;
http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.642448
► Accurate determination of surface texture is essential for the manufacturing of mechanical components within design specifications in engineering and materials science disciplines. It is also…
(more)
▼ Accurate determination of surface texture is essential for the manufacturing of mechanical components within design specifications in engineering and materials science disciplines. It is also required for any subsequent modifications to physical properties and functional aspects of the object. A number of methods are available to characterize any surface through the measurement of roughness parameters that can then be used to describe surface texture. These methods may be divided into those in that direct contact is made with the surface and those where such contact is not required. This report describes two methods approach for the surface profiling of a quartz glass substrate for step height, and tungsten substrate for roughness measure. A stylus profilometer (contact method) and vertical scanning interferometer, (VSI) or (non-contact optical method) were used for step height and roughness parameter measurements. A comparison was made with nominal values assigned to the studied surface, and conclusions drawn about the relative merits of the two methods. Those merits were found to differ, depending on the parameters under consideration. The stylus method gave better agreement of step height values for dimensions greater than a micron. Both methods showed excellent accuracy at smaller dimensions. Both methods also provided accurate average roughness values, although the VSI data significantly overestimated 35% above the peak-to-valley parameter. Likely sources and nature of such differences are discussed based on the results presented, as well as on the previous comparison studies reported in the literature. Because of such method-specific differences, the multi-technique approach used in this work for accurate surface profiling appears to be a more rational option than reliance upon a single method. Both contact and non-contact approaches have problems with specific roughness parameters, but a hybrid approach offers the possibility of combining the strengths of both methods and eliminating their individual weaknesses.
Subjects/Keywords: 620.1; Roughness; Instrument; Optical metrology
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MLA ·
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CSE |
Export
to Zotero / EndNote / Reference
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APA (6th Edition):
Jaturunruangsri, S. (2015). Evaluation of material surface profiling methods : contact versus non-contact. (Doctoral Dissertation). Brunel University. Retrieved from http://bura.brunel.ac.uk/handle/2438/10431 ; http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.642448
Chicago Manual of Style (16th Edition):
Jaturunruangsri, Supaporn. “Evaluation of material surface profiling methods : contact versus non-contact.” 2015. Doctoral Dissertation, Brunel University. Accessed April 20, 2021.
http://bura.brunel.ac.uk/handle/2438/10431 ; http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.642448.
MLA Handbook (7th Edition):
Jaturunruangsri, Supaporn. “Evaluation of material surface profiling methods : contact versus non-contact.” 2015. Web. 20 Apr 2021.
Vancouver:
Jaturunruangsri S. Evaluation of material surface profiling methods : contact versus non-contact. [Internet] [Doctoral dissertation]. Brunel University; 2015. [cited 2021 Apr 20].
Available from: http://bura.brunel.ac.uk/handle/2438/10431 ; http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.642448.
Council of Science Editors:
Jaturunruangsri S. Evaluation of material surface profiling methods : contact versus non-contact. [Doctoral Dissertation]. Brunel University; 2015. Available from: http://bura.brunel.ac.uk/handle/2438/10431 ; http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.642448

University of Surrey
19.
Hutchinson, Michael.
Inter-laboratory comparisons.
Degree: PhD, 1999, University of Surrey
URL: http://epubs.surrey.ac.uk/842963/
;
http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.298923
► A number of alloy bars were manufactured to some very precise specifications. Certain scientific institutions then performed chemical analyses and made several measurements of the…
(more)
▼ A number of alloy bars were manufactured to some very precise specifications. Certain scientific institutions then performed chemical analyses and made several measurements of the content of some chemical elements of interest. The measurements made on each of the alloy bars can be considered a set of repeated measurements. Modelling techniques for repeated measurements are now well established. Many of these techniques are based on the multivariate normal distribution with some specified mean and covariance structure. Modelling of the covariance structure is necessary so that efficient and meaningful inferences may be made about the mean structure. For the example of repeated measurements made on an alloy bar, the set of measurements is assumed to follow a multivariate normal distribution with a mean mu and a covariance structure Sigma. The choice of mu and Sigma is explored. Experiments which produce sets of repeated measurements can quite often result in a large amount of data being collected. This means that the use of statistical techniques to fit the model to the data can become computationally demanding. The use of maximum likelihood estimation is considered. Several aspects of constructing computationally efficient algorithms to maximise the likelihood function of the data are addressed. When the proposed model has been fitted to the data the suitability of the model and its assumptions are investigated. A score test is constructed to assess the correctness of the proposed covariance structure. Normal plots of the standardised residuals are used to assess other possible defects in the model, such as an incorrect assumption of normally distributed data. The work which has been carried out was motivated specifically by experiments where the set of repeated measurements came from a chemical analysis of an alloy material. It is the percentage content of a number of chemical elements which is of interest and the choice of statistical models was made with this in mind. However, it is demonstrated how the statistical techniques and models for the analysis of the chemical data may be used to analyse repeated measurements which arise from other kinds of experiments.
Subjects/Keywords: 530.8; Metrology
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APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Hutchinson, M. (1999). Inter-laboratory comparisons. (Doctoral Dissertation). University of Surrey. Retrieved from http://epubs.surrey.ac.uk/842963/ ; http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.298923
Chicago Manual of Style (16th Edition):
Hutchinson, Michael. “Inter-laboratory comparisons.” 1999. Doctoral Dissertation, University of Surrey. Accessed April 20, 2021.
http://epubs.surrey.ac.uk/842963/ ; http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.298923.
MLA Handbook (7th Edition):
Hutchinson, Michael. “Inter-laboratory comparisons.” 1999. Web. 20 Apr 2021.
Vancouver:
Hutchinson M. Inter-laboratory comparisons. [Internet] [Doctoral dissertation]. University of Surrey; 1999. [cited 2021 Apr 20].
Available from: http://epubs.surrey.ac.uk/842963/ ; http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.298923.
Council of Science Editors:
Hutchinson M. Inter-laboratory comparisons. [Doctoral Dissertation]. University of Surrey; 1999. Available from: http://epubs.surrey.ac.uk/842963/ ; http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.298923

Durham University
20.
Cockerton, Simon.
High resolution double crystal X-ray diffractometry and topography of III-V semiconductor compounds.
Degree: PhD, 1991, Durham University
URL: http://etheses.dur.ac.uk/6278/
;
http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.305568
► Double crystal diffractometry and topography are now routinely used in many laboratories for the inspection of epitaxially grown devices. However the trend towards thinner layers…
(more)
▼ Double crystal diffractometry and topography are now routinely used in many laboratories for the inspection of epitaxially grown devices. However the trend towards thinner layers and more complex structures requires the continued development of novel approaches using these techniques. This thesis is concerned with the development of these approaches to study the structural uniformity of semiconductor materials. The uniformity of large single crystals of lithium niobate has been studied using synchrotron radiation and double crystal X-ray topography. This study has shown a variety of contrast features including low angle grain boundaries and non-uniform dislocation densities. The abruptness of an interface between a layer and the underlying substrate has been studied using glancing incidence asymmetric reflections. Comparisons to simulated structures revealed that a closer match was achieved by the inclusion of a highly mismatched interfacial layer. This study illustrates the need for careful comparison between experimental and simulated rocking curves as different structures may produce very similar rocking curves. A double crystal topographic study of a AlGaAs laser structure revealed X-ray interference fringes. These are shown to be produced from the interaction of two simultaneously diffracting layers separated by a thin layer. Possible formation mechanisms have been discussed showing that these fringes are capable of revealing changes in the active layer at the atomic level. A novel approach has also been developed using synchrotron radiation to study the non-stoichiometry of GaAs. This approach uses the quasi-forbidden reflections which are present in III-V semiconductors due to the differences in the atomic scattering factors. This study has also discussed the behaviour of strong and weak reflections in the region of absorption edges and modelled their behaviour using the anomalous dispersion corrections of Cromer and Liberman.
Subjects/Keywords: 530.8; Metrology
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APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
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APA (6th Edition):
Cockerton, S. (1991). High resolution double crystal X-ray diffractometry and topography of III-V semiconductor compounds. (Doctoral Dissertation). Durham University. Retrieved from http://etheses.dur.ac.uk/6278/ ; http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.305568
Chicago Manual of Style (16th Edition):
Cockerton, Simon. “High resolution double crystal X-ray diffractometry and topography of III-V semiconductor compounds.” 1991. Doctoral Dissertation, Durham University. Accessed April 20, 2021.
http://etheses.dur.ac.uk/6278/ ; http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.305568.
MLA Handbook (7th Edition):
Cockerton, Simon. “High resolution double crystal X-ray diffractometry and topography of III-V semiconductor compounds.” 1991. Web. 20 Apr 2021.
Vancouver:
Cockerton S. High resolution double crystal X-ray diffractometry and topography of III-V semiconductor compounds. [Internet] [Doctoral dissertation]. Durham University; 1991. [cited 2021 Apr 20].
Available from: http://etheses.dur.ac.uk/6278/ ; http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.305568.
Council of Science Editors:
Cockerton S. High resolution double crystal X-ray diffractometry and topography of III-V semiconductor compounds. [Doctoral Dissertation]. Durham University; 1991. Available from: http://etheses.dur.ac.uk/6278/ ; http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.305568

University of Waterloo
21.
Wang, Marc.
Part Performance Measurement, Analysis and Optimization for Binder Jetting Additive Manufacturing.
Degree: 2020, University of Waterloo
URL: http://hdl.handle.net/10012/16455
► Binder Jetting (BJ) is an additive manufacturing (AM) process where objects are formed layer by layer. The manufacturing of parts is performed by depositing powder…
(more)
▼ Binder Jetting (BJ) is an additive manufacturing (AM) process where objects are formed layer by layer. The manufacturing of parts is performed by depositing powder layer by layer and binding them together using a binding agent resulting in a green part. This is followed by thermal processing to fuse powder particles together.
Unfortunately, achieving full density through the thermal process is difficult due to the low initial density of the green part. Full density will result in substantial shrinkage. Consequentially, there is an incentive to maximize the density of the green part. Sadly, due to the presence of surface connected pores, measuring the density of green parts is not trivial. This work will propose a measurement methodology for measuring green density and processing computed tomography images obtained from green binder jetting parts. It was discovered that no standard was codified for the density measurement of such parts using either Archimedes or Micro-Tomography. Based on experimentally informed analysis, the use of the methodology ISO 5013 for measuring relative bulk density is recommended. Among the three methodologies evaluated (oil infiltration and wax coating), ISO 5013 was the method with the lowest average estimated measurement error (0.36%). In parallel, computed tomography datasets were analyzed, where multiple global threshold techniques were evaluated to extract bulk density metrics. Through experimentally informed analysis, the threshold method Otsu, Mean and Isodata were the most consistent at segmenting computed tomography image of green samples.
The second section of this thesis tackles heterogeneity issues found in previous work. Wheat et al. attributed the heterogeneity to powder segregation. Unfortunately, due to the fragility of green BJAM parts, only computed tomography could observe the internal powder arrangement. Consequently, particle segmentation and detection software was developed, specifically tailored towards capturing the particle space for BJAM parts. Two approaches were tried: curvature-based watershed segmentation and Mask-RCNN. The micro-tomography images were knowingly degraded to achieve high data acquisition throughput. Unfortunately, this heavily degraded the performance of both Watershed and Mask-RCNN segmentation. Watershed segmentation displayed acceptable segmentation (70.7%) but poor detection performance (26.6%). Alternatively, Mask-RCNN scored similar segmentation performance (71.3%) with watershed but with twice the detection (48.1%). Regrettably, current performance of Mask-RCNN are inadequate for use in detecting particle segregation.
The last section proposes the use of multi-objective Bayesian optimization algorithm for optimizing the process parameters for BJAM. The proposed algorithm managed to minimize porosity (37.5%), while keeping print time low (87 min). Unfortunately, dimensional fidelity were still low (Δ 2.33 x 1.86 x 1.95 mm). The method has the potential of reducing the number of empirical trials to perform optimization, while…
Subjects/Keywords: additive manufacturing; optimization; metrology
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Wang, M. (2020). Part Performance Measurement, Analysis and Optimization for Binder Jetting Additive Manufacturing. (Thesis). University of Waterloo. Retrieved from http://hdl.handle.net/10012/16455
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Wang, Marc. “Part Performance Measurement, Analysis and Optimization for Binder Jetting Additive Manufacturing.” 2020. Thesis, University of Waterloo. Accessed April 20, 2021.
http://hdl.handle.net/10012/16455.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Wang, Marc. “Part Performance Measurement, Analysis and Optimization for Binder Jetting Additive Manufacturing.” 2020. Web. 20 Apr 2021.
Vancouver:
Wang M. Part Performance Measurement, Analysis and Optimization for Binder Jetting Additive Manufacturing. [Internet] [Thesis]. University of Waterloo; 2020. [cited 2021 Apr 20].
Available from: http://hdl.handle.net/10012/16455.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Wang M. Part Performance Measurement, Analysis and Optimization for Binder Jetting Additive Manufacturing. [Thesis]. University of Waterloo; 2020. Available from: http://hdl.handle.net/10012/16455
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of Toronto
22.
Sahota, Jaspreet.
Quantum-enhanced Phase Estimation in Optical Interferometry.
Degree: PhD, 2017, University of Toronto
URL: http://hdl.handle.net/1807/80851
► Quantum-enhanced interferometers utilize non-classical states of light in order to surpass the limitations imposed by classical physics on phase measurement sensitivity and resolution. We review…
(more)
▼ Quantum-enhanced interferometers utilize non-classical states of light in order to surpass the limitations imposed by classical physics on phase measurement sensitivity and resolution. We review key scientific developments in this growing field of research and derive fundamental
metrology concepts, namely the Cramér-Rao bound and the Fisher information, which are used to analyze the metrological performance of quantum states of light.
We propose a supersensitive quantum interferometry protocol that can be amplified to the macroscopic realm (i.e. the mean number of photons of the probe state can reach approximately 100,000 photons) using contemporary techniques of spontaneous parametric down conversion. The parity measurement on the output field asymptotically saturates the quantum Cramér-Rao bound, which scales like the Heisenberg limit.
We uncover the role of photon statistics on phase sensitivity and rule out the necessity of mode entanglement for quantum-enhanced interferometry. Based on these insights we outline a practical
metrology technique (independent of mode entanglement) that measures a phase delay of a single-mode anti-squeezing operation. This scheme can also be scaled macroscopically using contemporary techniques and is shown to significantly surpass the shot-noise limit (SNL) in the presence of realistic losses.
Finally, the physical resources that enable quantum-enhanced interferometry is studied by analyzing the quantum Fisher information (QFI) using the first quantization and the second quantization formalisms of quantum mechanics. It is shown that increasing the intra-mode correlations of an interferometer (as quantified by the second order Glauber coherence function) can be conducive to attaining a quantum advantage in phase estimation; whereas, introducing mode entanglement can reduce phase sensitivity. Using the first quantization description, we derive a formula for the QFI that shows explicitly how the Heisenberg scaling term depends on particle entanglement.
Advisors/Committee Members: James, Daniel F. V., Physics.
Subjects/Keywords: Interferometry; Metrology; Quantum Optics; 0599
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Sahota, J. (2017). Quantum-enhanced Phase Estimation in Optical Interferometry. (Doctoral Dissertation). University of Toronto. Retrieved from http://hdl.handle.net/1807/80851
Chicago Manual of Style (16th Edition):
Sahota, Jaspreet. “Quantum-enhanced Phase Estimation in Optical Interferometry.” 2017. Doctoral Dissertation, University of Toronto. Accessed April 20, 2021.
http://hdl.handle.net/1807/80851.
MLA Handbook (7th Edition):
Sahota, Jaspreet. “Quantum-enhanced Phase Estimation in Optical Interferometry.” 2017. Web. 20 Apr 2021.
Vancouver:
Sahota J. Quantum-enhanced Phase Estimation in Optical Interferometry. [Internet] [Doctoral dissertation]. University of Toronto; 2017. [cited 2021 Apr 20].
Available from: http://hdl.handle.net/1807/80851.
Council of Science Editors:
Sahota J. Quantum-enhanced Phase Estimation in Optical Interferometry. [Doctoral Dissertation]. University of Toronto; 2017. Available from: http://hdl.handle.net/1807/80851

University of Arizona
23.
Graves, Logan Rodriguez.
Freeform Metrology Using Deflectometry
.
Degree: 2019, University of Arizona
URL: http://hdl.handle.net/10150/634398
► Precision freeform optics are finding increased usage in new optical systems. Deflectometry is a non-null optical metrology method that has great application potential to be…
(more)
▼ Precision freeform optics are finding increased usage in new optical systems. Deflectometry is a non-null optical
metrology method that has great application potential to be a measurement method for freeform and standard optics, offering a wide slope dynamic range and excellent accuracy and precision. The technique utilizes a known source which emits rays of light that are deflected by the unit under test (UUT) and are captured by a recording camera. By knowing the precise location of the source, the ray intercepts at the UUT, and the camera, the local surface slopes of the UUT can be determined and integrated to obtain a reconstructed surface. This study investigates three major topics to improve deflectometry and identify new Deflectometric based techniques.
The first topic explored is a software-based method for an iterative surface reconstruction process. Deflectometry relies on determining the local surface slopes of the UUT by precisely knowing the ray intercept locations at the surface. Any error in the assumed surface model therefore directly reduces the reconstructed surface accuracy. A new processing method was developed called model-free deflectometry, which requires no optical surface model, and instead iteratively reconstructs the optical surface leading to improved final reconstruction accuracy. The method was used to reduce departure of a freeform optic from interferometric results from 15.80 𝜇m root-mean-square (RMS) using model-based deflectometry down to 5.20 𝜇m RMS with the model-free method developed. Further, most of the 5.20 𝜇m RMS residual departure was explained using a simulation to model the inherent noise present from hardware limitations.
The second topic is a deflectometry system configuration which generates a virtual 2π steradian measurement volume, enabling full aperture deflectometry measurements of previously unmeasurable flat and convex freeform optics. The technique utilizes a source tilted over the UUT, enabling at least a partial aperture test. However, by clocking the UUT, a series of virtual sources are generated, which when considered as a whole, create a virtual source enclosure around the UUT allowing for a full aperture test. The method was shown to have accuracy similar to an interferometric test for a fast F/1.26 convex sphere and successfully tested a highly freeform Alvarez lens.
Lastly, a power scalable, time-modulated high stability infrared source is explored for infrared deflectometry. The new source is an integrating box design with a precision emission area machine cut into an aluminum box. The light sources are modular high-efficiency resistive alloy membranes held in small caps. The design allows for power scaling by adding or removing caps from the source design. The caps are powered in parallel and are modulated at approximately 1 Hz to allow for signal isolation, thereby greatly improving signal to noise ratio. The new source was compared with a traditional tungsten source, both run at the same power output, and the source stability and geometry compared.…
Advisors/Committee Members: Kim, Dae Wook (advisor), Smith, Gregory (committeemember), Schwiegerling, James (committeemember), Koshel, R. John (committeemember).
Subjects/Keywords: deflectometry;
metrology;
optical fabrication
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Graves, L. R. (2019). Freeform Metrology Using Deflectometry
. (Doctoral Dissertation). University of Arizona. Retrieved from http://hdl.handle.net/10150/634398
Chicago Manual of Style (16th Edition):
Graves, Logan Rodriguez. “Freeform Metrology Using Deflectometry
.” 2019. Doctoral Dissertation, University of Arizona. Accessed April 20, 2021.
http://hdl.handle.net/10150/634398.
MLA Handbook (7th Edition):
Graves, Logan Rodriguez. “Freeform Metrology Using Deflectometry
.” 2019. Web. 20 Apr 2021.
Vancouver:
Graves LR. Freeform Metrology Using Deflectometry
. [Internet] [Doctoral dissertation]. University of Arizona; 2019. [cited 2021 Apr 20].
Available from: http://hdl.handle.net/10150/634398.
Council of Science Editors:
Graves LR. Freeform Metrology Using Deflectometry
. [Doctoral Dissertation]. University of Arizona; 2019. Available from: http://hdl.handle.net/10150/634398

University of Waterloo
24.
Mohammadi, Fatemeh.
3D optical metrology by digital moiré: Pixel-wise calibration refinement, grid removal, and temporal phase unwrapping.
Degree: 2017, University of Waterloo
URL: http://hdl.handle.net/10012/11260
► Fast, accurate three dimensional (3D) optical metrology has diverse applications in object and environment modelling. Structured-lighting techniques allow non-contacting 3D surface-shape measurement by projecting patterns…
(more)
▼ Fast, accurate three dimensional (3D) optical metrology has diverse applications in object and environment modelling. Structured-lighting techniques allow non-contacting 3D surface-shape measurement by projecting patterns of light onto an object surface, capturing images of the deformed patterns, and computing the 3D surface geometry from the captured 2D images. However, motion artifacts can still be a problem with high-speed surface-motion especially with increasing demand for higher measurement resolution and accuracy.
To avoid motion artifacts, fast 2D image acquisition of projected patterns is required. Fast multi-pattern projection and minimization of the number of projected patterns are two approaches for dynamic object measurement. To achieve a higher rate of switching frames, fast multi-pattern projection techniques require costly projector hardware modification or new designs of projection systems to increase the projection rate beyond the capabilities of off-the-shelf projectors. Even if these disadvantages were acceptable (higher cost, complex hardware), and even if the rate of acquisition achievable with current systems were fast enough to avoid errors, minimization of the number of captured frames required will still contribute to reduce further the effect of object motion on measurement accuracy and to enable capture of higher object dynamics. Development of an optical 3D metrology method that minimizes the number of projected patterns while maintaining accurate 3D surface-shape measurement of objects with continuous and discontinuous surface geometry has remained a challenge.
Capture of a single image-frame instead of multiple frames would be advantageous for measuring moving or deforming objects. Since accurate measurement generally requires multiple phase-shifted images, imbedding multiple patterns into a single projected composite pattern is one approach to achieve accurate single-frame 3D surface-shape measurement. The main limitations of existing single-frame methods based on composite patterns are poor resolution, small range of gray-level intensity due to collection of multiple patterns in one image, and degradation of the extracted patterns because of modulation and demodulation processes on the captured composite pattern image.
To benefit from the advantages of multi-pattern projection of phase-shifted fringes and single-frame techniques, without combining phase-shifted patterns into one frame, digital moiré was used. Moiré patterns are generated by projecting a grid pattern onto the object, capturing a single frame, and in a post-process, superimposing a synthetic grid of the same frequency as in the captured image. Phase-shifting is carried out as a post-process by digitally shifting the synthetic grid across the captured image. The useful moiré patterns, which contain object shape information, are contaminated with a high-frequency grid lines that must be removed. After performing grid removal, computation of a phase map, and phase-to-height mapping, 3D object shape can be…
Subjects/Keywords: 3D optical metrology; Digital moiré
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Mohammadi, F. (2017). 3D optical metrology by digital moiré: Pixel-wise calibration refinement, grid removal, and temporal phase unwrapping. (Thesis). University of Waterloo. Retrieved from http://hdl.handle.net/10012/11260
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Mohammadi, Fatemeh. “3D optical metrology by digital moiré: Pixel-wise calibration refinement, grid removal, and temporal phase unwrapping.” 2017. Thesis, University of Waterloo. Accessed April 20, 2021.
http://hdl.handle.net/10012/11260.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Mohammadi, Fatemeh. “3D optical metrology by digital moiré: Pixel-wise calibration refinement, grid removal, and temporal phase unwrapping.” 2017. Web. 20 Apr 2021.
Vancouver:
Mohammadi F. 3D optical metrology by digital moiré: Pixel-wise calibration refinement, grid removal, and temporal phase unwrapping. [Internet] [Thesis]. University of Waterloo; 2017. [cited 2021 Apr 20].
Available from: http://hdl.handle.net/10012/11260.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Mohammadi F. 3D optical metrology by digital moiré: Pixel-wise calibration refinement, grid removal, and temporal phase unwrapping. [Thesis]. University of Waterloo; 2017. Available from: http://hdl.handle.net/10012/11260
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Louisiana State University
25.
Gard, Bryan Tomas.
Advances in Quantum Metrology: Continuous Variables in Phase Space.
Degree: PhD, Physical Sciences and Mathematics, 2016, Louisiana State University
URL: etd-04062016-162646
;
https://digitalcommons.lsu.edu/gradschool_dissertations/2089
► This dissertation serves as a general introduction to Wigner functions, phase space, and quantum metrology but also strives to be useful as a how-to guide…
(more)
▼ This dissertation serves as a general introduction to Wigner functions, phase space, and quantum metrology but also strives to be useful as a how-to guide for those who wish to delve into the realm of using continuous variables, to describe quantum states of light and optical interferometry. We include many of the introductory elements one needs to appreciate the advantages of this treatment as well as show many examples in an effort to make this dissertation more friendly. In the initial segment of this dissertation, we focus on the advantages of Wigner functions and their use to describe many quantum states of light. We focus on coherent states and squeezed vacuum with a Mach Zehnder Interferometer for many of our examples, also used by experiments such as advanced LIGO. Later, we will also analyze this setup in more detail with a full example including the effects of many noise sources such as phase drift, photon loss, inefficient detectors, and thermal noise. In this setup, we also show the optimal measurement scheme, which is currently not employed in experiment. Throughout our metrology discussions, we will also discuss various quantum limits and use quantum Fisher information to show optimal bounds. When applicable, we also discuss the use of quantum Gaussian information and how it relates to our Wigner function treatment. The remainder of our discussion focuses on investigating the effects of photon addition and subtraction to various states of light and analyze the nondeterministic nature of this process. We use examples of m photon additions to a coherent state as well as discuss the properties of an m photon subtracted thermal state. We also provide an argument that this process must always be a nondeterministic one, or the ability to violate quantum limits becomes apparent. We show that using phase measurement as one's metric is much more restrictive, which limits the usefulness of photon addition and subtraction. When we consider SNR however, we show improved SNR statistics, at the cost of increased measurement time. In this case of SNR, we also quantify the efficiency of the photon addition and subtraction process.
Subjects/Keywords: Metrology; Optics; Quantum; Phase space
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Gard, B. T. (2016). Advances in Quantum Metrology: Continuous Variables in Phase Space. (Doctoral Dissertation). Louisiana State University. Retrieved from etd-04062016-162646 ; https://digitalcommons.lsu.edu/gradschool_dissertations/2089
Chicago Manual of Style (16th Edition):
Gard, Bryan Tomas. “Advances in Quantum Metrology: Continuous Variables in Phase Space.” 2016. Doctoral Dissertation, Louisiana State University. Accessed April 20, 2021.
etd-04062016-162646 ; https://digitalcommons.lsu.edu/gradschool_dissertations/2089.
MLA Handbook (7th Edition):
Gard, Bryan Tomas. “Advances in Quantum Metrology: Continuous Variables in Phase Space.” 2016. Web. 20 Apr 2021.
Vancouver:
Gard BT. Advances in Quantum Metrology: Continuous Variables in Phase Space. [Internet] [Doctoral dissertation]. Louisiana State University; 2016. [cited 2021 Apr 20].
Available from: etd-04062016-162646 ; https://digitalcommons.lsu.edu/gradschool_dissertations/2089.
Council of Science Editors:
Gard BT. Advances in Quantum Metrology: Continuous Variables in Phase Space. [Doctoral Dissertation]. Louisiana State University; 2016. Available from: etd-04062016-162646 ; https://digitalcommons.lsu.edu/gradschool_dissertations/2089

Louisiana State University
26.
Adhikari, Sushovit.
Phase Estimation in Linear and Nonlinear Interferometers.
Degree: PhD, Atomic, Molecular and Optical Physics, Louisiana State University
URL: https://digitalcommons.lsu.edu/gradschool_dissertations/4811
► Phase estimation has a wide range of applications. Over the years, several strategies have been studied to improve precision in phase estimation. These strategies…
(more)
▼ Phase estimation has a wide range of applications. Over the years, several strategies have been studied to improve precision in phase estimation. These strategies include using exotic quantum states to quantum detection schemes. This dissertation summarizes my effort in improving the precision of phase estimation with a linear and nonlinear interferometer.
Chapter 1 introduces quantum optics and quantum metrology. I introduce all relevant quantum states of light used. We also look into tools and terminologies of quantum metrology such as Fisher information, shot-noise limit, Heisenberg limit, etc., along with examples of phase estimation with a Mach-Zehnder interferometer.
In Chapter 2, I discuss multiple phase estimation using a multimode interferometer. Building upon previous work, our scheme consists of a multimode interferometer with single-photon inputs. By using a quantum Fisher information analysis, we show that our scheme gives a constant improvement over other schemes. We also show that our scheme with photon-number-resolving detection approaches the quantum Cram\'er-Rao bound. Moreover, we also consider the probabilistic nature of photon emission at the input, and we study its effect on phase sensitivity.
I discuss phase estimation with SU(1,1) interferometer in Chapter 3. We look at phase sensitivity in this interferometer with different input states. Namely, we consider two different phase estimation scheme, one using thermal and squeezed states, and others using coherent and displaced squeezed states with parity and on-off as a detection scheme. We also look into the effect of photon loss inside the interferometer.
In Chapter 4, we revisit phase estimation in SU(1,1) interferometer from the perspective of quantum Fisher information. I discuss in detail a longstanding confusion regarding the use of quantum Fisher information in SU(1,1) interferometer. We show that phase averaging or quantum Fisher information matrix method is needed in general for calculating the phase sensitivity which resolves inconsistencies reported in previously published articles.
Subjects/Keywords: Quantum Metrology
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Adhikari, S. (n.d.). Phase Estimation in Linear and Nonlinear Interferometers. (Doctoral Dissertation). Louisiana State University. Retrieved from https://digitalcommons.lsu.edu/gradschool_dissertations/4811
Note: this citation may be lacking information needed for this citation format:
No year of publication.
Chicago Manual of Style (16th Edition):
Adhikari, Sushovit. “Phase Estimation in Linear and Nonlinear Interferometers.” Doctoral Dissertation, Louisiana State University. Accessed April 20, 2021.
https://digitalcommons.lsu.edu/gradschool_dissertations/4811.
Note: this citation may be lacking information needed for this citation format:
No year of publication.
MLA Handbook (7th Edition):
Adhikari, Sushovit. “Phase Estimation in Linear and Nonlinear Interferometers.” Web. 20 Apr 2021.
Note: this citation may be lacking information needed for this citation format:
No year of publication.
Vancouver:
Adhikari S. Phase Estimation in Linear and Nonlinear Interferometers. [Internet] [Doctoral dissertation]. Louisiana State University; [cited 2021 Apr 20].
Available from: https://digitalcommons.lsu.edu/gradschool_dissertations/4811.
Note: this citation may be lacking information needed for this citation format:
No year of publication.
Council of Science Editors:
Adhikari S. Phase Estimation in Linear and Nonlinear Interferometers. [Doctoral Dissertation]. Louisiana State University; Available from: https://digitalcommons.lsu.edu/gradschool_dissertations/4811
Note: this citation may be lacking information needed for this citation format:
No year of publication.

Louisiana State University
27.
Studer, Nicholas Michael.
Optimization of Quantum Optical Metrology Systems.
Degree: PhD, Atomic, Molecular and Optical Physics, 2019, Louisiana State University
URL: https://digitalcommons.lsu.edu/gradschool_dissertations/4842
► It can be said that all of humanity's efforts can be understood as a problem of optimization. We each have a natural sense of…
(more)
▼ It can be said that all of humanity's efforts can be understood as a problem of optimization. We each have a natural sense of what is ``good'' or ``bad'' and thus our actions tend towards maximizing – or optimizing – some notion of good and minimizing those things we perceive as bad or undesirable.
Within the sciences, the greatest form of good is knowledge. It is this pursuit of knowledge that leads to not only life-saving innovations and technology, but also to furthering our understanding of our natural world and driving our philosophical pursuits.
The principle method of obtaining knowledge in the sciences is by performing measurements; the simple act of comparing one attribute of a system to a known standard and recording the observed value is how all scientific progress is made. The act of performing measurements is in fact so important that there is an entire field of study surrounding it: metrology.
One critical component of metrology is the development of new techniques to perform measurements, or alternative measurement schemes that are more optimal in some way. This is where there is room to exploit quantum physics to improve our techniques \ – we can perform quantum metrology. In quantum mechanics we routinely deal with the smallest, weakest, most delicate of systems. Quantum properties are inherently very sensitive to their environment; this of course makes them highly intolerant of noise but also makes them great resources to perform sensitive measurements. Quantum metrology concerns itself with utilizing quantum phenomena to extract more information from the natural world than is possible by conventional, or classical, means.
To perform optimal measurements, these quantum systems must of course be optimal by some metric. Performing the ``optimal'' measurement requires several ingredients. First, we need the optimal tools or instrumentation. In quantum mechanical language, this means we need the optimal probe state. Then, we need to optimize the interaction of our instrumentation with the system we which to interrogate so that we can extract the desired information. This translates to needing the best possible interaction between the probe state and the system in question – in other words, we need to optimize the evolution of the probe. Finally, we must take care to extract the most information as possible at the output; we must not neglect any information present in the evolved probe state.
The entire quantum metrology process can be summarized as thus: probe state preparation, probe state evolution, and evolved state detection. These elements make up the basis of this thesis. Within, I will discuss several works in which I optimize the performance of systems that implement these metrology elements. Specifically, I will first discuss one such system in which I optimize the probe interrogation of the phase, i.e. perform phase-estimation, in a Boson-sampling device. Then, I will show some strategies to progressively build up highly-useful Fock states starting…
Subjects/Keywords: quantum optics; quantum metrology
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Studer, N. M. (2019). Optimization of Quantum Optical Metrology Systems. (Doctoral Dissertation). Louisiana State University. Retrieved from https://digitalcommons.lsu.edu/gradschool_dissertations/4842
Chicago Manual of Style (16th Edition):
Studer, Nicholas Michael. “Optimization of Quantum Optical Metrology Systems.” 2019. Doctoral Dissertation, Louisiana State University. Accessed April 20, 2021.
https://digitalcommons.lsu.edu/gradschool_dissertations/4842.
MLA Handbook (7th Edition):
Studer, Nicholas Michael. “Optimization of Quantum Optical Metrology Systems.” 2019. Web. 20 Apr 2021.
Vancouver:
Studer NM. Optimization of Quantum Optical Metrology Systems. [Internet] [Doctoral dissertation]. Louisiana State University; 2019. [cited 2021 Apr 20].
Available from: https://digitalcommons.lsu.edu/gradschool_dissertations/4842.
Council of Science Editors:
Studer NM. Optimization of Quantum Optical Metrology Systems. [Doctoral Dissertation]. Louisiana State University; 2019. Available from: https://digitalcommons.lsu.edu/gradschool_dissertations/4842

Louisiana State University
28.
You, Chenglong.
Precision of Parameter Estimation in Quantum Metrology.
Degree: PhD, Quantum Physics, 2019, Louisiana State University
URL: https://digitalcommons.lsu.edu/gradschool_dissertations/4849
► The fundamental precision limit of an interferometer is crucial since it bounds the best possible sensitivity one could achieve using such a device. This…
(more)
▼ The fundamental precision limit of an interferometer is crucial since it bounds the best possible sensitivity one could achieve using such a device. This thesis will focus on several different interferometers and try to give the ultimate precision bounds by carefully counting all the resources used in the interferometers.
The thesis begins with the basics of the quantum state of light. The fundamentals of quantum metrology are also reviewed and discussed. More specifically, the terminology of classical and quantum Cram\'er-Rao bound and classical and quantum Fisher information are introduced.
Chapter 3 discusses the conclusive precision bounds in two-mode interferometer such as Mach-Zehnder interferometer (MZI) and SU(1,1) interferometer. I revisit the quantum Fisher information approach of these two interferometers and show the discrepancy of phase sensitivity on the physically same setup. Then I establish fundamental precision estimation bounds for such device, due to the reason that many works of literature fail to accurately count the resources and knowledge of phase-to-be-estimated used in the interferometers. The analysis suggests that for a MZI, one can never do better than SNL in phase sensitivity, when an input to one of the two ports is the vacuum. If one does not allow the detector to use any external phase reference or power resource, then the precision is limited by the SNL. For a SU(1,1) interferometer, firstly, when one of the input states is restricted to be a vacuum state, I showed that by using either the phase-averaging method or the quantum Fisher information matrix method, different phase configurations of the SU(1,1) interferometer result in the same QFI. Secondly, I compared the results of the phase-averaging method and the quantum Fisher information matrix method, and then I argued that for an SU(1,1) interferometer, phase averaging or quantum Fisher information matrix method is generally required, and they are equivalent. Finally, I used the quantum Fisher information matrix method to calculate the precision limit for other common input states, such as two coherent state inputs or coherent state with squeezed vacuum inputs.
In chapter 4, I will consider a passive multi-mode interferometer for multiparameter phase estimation. It was suggested that optical networks with relatively inexpensive overhead – single photon Fock states, passive optical elements, and single photon detection – can show significant improvements over classical strategies for single-parameter estimation, when the number of modes in the network is small. In this chapter, I analytically compute the quantum Cramer-Rao bound to show these networks can have a constant-factor quantum advantage in multi-parameter estimation for even large number of modes. Additionally, I provide a simplified measurement scheme using an array of single photon detectors and only one number-resolving detector that is capable of approximately obtaining this sensitivity for a small number of modes. Remarkably, supersensitivity…
Subjects/Keywords: Parameter estimation; Quantum metrology
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
You, C. (2019). Precision of Parameter Estimation in Quantum Metrology. (Doctoral Dissertation). Louisiana State University. Retrieved from https://digitalcommons.lsu.edu/gradschool_dissertations/4849
Chicago Manual of Style (16th Edition):
You, Chenglong. “Precision of Parameter Estimation in Quantum Metrology.” 2019. Doctoral Dissertation, Louisiana State University. Accessed April 20, 2021.
https://digitalcommons.lsu.edu/gradschool_dissertations/4849.
MLA Handbook (7th Edition):
You, Chenglong. “Precision of Parameter Estimation in Quantum Metrology.” 2019. Web. 20 Apr 2021.
Vancouver:
You C. Precision of Parameter Estimation in Quantum Metrology. [Internet] [Doctoral dissertation]. Louisiana State University; 2019. [cited 2021 Apr 20].
Available from: https://digitalcommons.lsu.edu/gradschool_dissertations/4849.
Council of Science Editors:
You C. Precision of Parameter Estimation in Quantum Metrology. [Doctoral Dissertation]. Louisiana State University; 2019. Available from: https://digitalcommons.lsu.edu/gradschool_dissertations/4849

Louisiana State University
29.
Jiang, Kebei.
Quantum Optical Metrology, Sensing and Imaging.
Degree: PhD, Physical Sciences and Mathematics, 2014, Louisiana State University
URL: etd-05282014-134705
;
https://digitalcommons.lsu.edu/gradschool_dissertations/3138
► In this dissertation we begin with a brief introduction to quantum optics concentrating on the topics of the noise of quantum optical states, quantum estimation…
(more)
▼ In this dissertation we begin with a brief introduction to quantum optics concentrating on the topics of the noise of quantum optical states, quantum estimation theory, quantum interferometry and the atom-field interaction. This background is necessary for understanding the discussions in later chapters. In particular, quantum interferometry, which is optical interferometry when the light source is a quantum mechanical state, plays a central role in this dissertation. In Chapter 2 we discuss the phase estimation sensitivity of quantum metrology when photon loss is present. In Chapter 3 we extend the discussion to include the phase fluctuation of the system caused by the environment. We model our metrological system with the Mach-Zehnder interferometer (MZI) and use a light field in the symmetric number-path entangled state as the source. In both chapters we use the parity operator as the detection scheme and show that it is optimal under pure dephasing. In Chapter 4 we discuss the application of quantum optical states in remote sensing and propose a new scheme for a quantum radar. Again, our scheme consists of a MZI and a coherent light source. It is shown that using only coherent states of light and quantum homodyne detection, super-resolving ranging and angle determination are achievable. Chapter 5 is devoted to the generation of a super-resolving single-photon number-path entangled state which may serve as a proof-of-principle prototype for quantum lithography. The repeated implementation of MZIs is shown to be able to remove photons coherently from both modes of a symmetric number-path entangled state with arbitrarily high photon number. Lastly, in Chapter 6 we introduce the phenomenon known as polarization self-rotation and discuss its potential in generating a squeezed vacuum state, which has a huge impact in quantum interferometry.
Subjects/Keywords: quantum optics; metrology; sensing; imaging
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APA (6th Edition):
Jiang, K. (2014). Quantum Optical Metrology, Sensing and Imaging. (Doctoral Dissertation). Louisiana State University. Retrieved from etd-05282014-134705 ; https://digitalcommons.lsu.edu/gradschool_dissertations/3138
Chicago Manual of Style (16th Edition):
Jiang, Kebei. “Quantum Optical Metrology, Sensing and Imaging.” 2014. Doctoral Dissertation, Louisiana State University. Accessed April 20, 2021.
etd-05282014-134705 ; https://digitalcommons.lsu.edu/gradschool_dissertations/3138.
MLA Handbook (7th Edition):
Jiang, Kebei. “Quantum Optical Metrology, Sensing and Imaging.” 2014. Web. 20 Apr 2021.
Vancouver:
Jiang K. Quantum Optical Metrology, Sensing and Imaging. [Internet] [Doctoral dissertation]. Louisiana State University; 2014. [cited 2021 Apr 20].
Available from: etd-05282014-134705 ; https://digitalcommons.lsu.edu/gradschool_dissertations/3138.
Council of Science Editors:
Jiang K. Quantum Optical Metrology, Sensing and Imaging. [Doctoral Dissertation]. Louisiana State University; 2014. Available from: etd-05282014-134705 ; https://digitalcommons.lsu.edu/gradschool_dissertations/3138
30.
Thompson, Martin.
Matrix effects in differential scanning calorimetry.
Degree: PhD, 1991, Open University
URL: http://oro.open.ac.uk/65852/
;
https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.281223
► Problems arise in differential scanning calorimetry (DSC) when large samples and high levels of amplification are used to enhance sensitivity. Artifact peaks are generated by…
(more)
▼ Problems arise in differential scanning calorimetry (DSC) when large samples and high levels of amplification are used to enhance sensitivity. Artifact peaks are generated by the instrument, calorimetric sensitivity is reduced and DSC peaks are distorted as the transition interface passes through the specimen. These effects have been investigated by peak shape analysis for fusion, crystallisation and a polymorphic transition occurring in model DSC specimens. The results were used to develop two techniques for studying interactions in solid composites by means of heat-flux DSC. These novel techniques were applied to solid composites containing porphyrins and nickel(II) oxide. One of the techniques utilised an improved procedure for measuring the thermal conductivity (λ) of small samples. Values of λ were measured for several pure porphyrins and composites, and the results compared with calculated values from various mathematical models which predict transport properties. This allowed structural changes at the interface between the solid phases to be inferred. The occurrence of these changes was supported by electron microscopy. The second technique was designed to isolate relatively weak DSC peaks from background interference. A fully reacted composite specimen was used to generate a reference DSC curve, which was subtracted from the initial DSC scan. This compensated for the varying heat capacity and Néel transition in nickel(II) oxide, and allowed two types of event to be detected. One of these appeared to be a general feature for free-base porphyrins, corresponding to formation of a nickel-porphyrin complex and water. Reaction began at 0.5-0.6 of the fusion temperature (T/K) for the porphyrin, which Tammann's rule identifies as the region where lattice mobility becomes significant. The second type of event appeared as a very sharp exothermic peak, whose onset corresponded to decomposition of carbonate and hydroxide functions associated with nickel. Rapid acceleration of the process occurred at the Néel transition point in nickel(II) oxide. Both events are believed to represent interactions at the interface between the solid phases.
Subjects/Keywords: 530.8; Metrology
Record Details
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Record Details
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Thompson, M. (1991). Matrix effects in differential scanning calorimetry. (Doctoral Dissertation). Open University. Retrieved from http://oro.open.ac.uk/65852/ ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.281223
Chicago Manual of Style (16th Edition):
Thompson, Martin. “Matrix effects in differential scanning calorimetry.” 1991. Doctoral Dissertation, Open University. Accessed April 20, 2021.
http://oro.open.ac.uk/65852/ ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.281223.
MLA Handbook (7th Edition):
Thompson, Martin. “Matrix effects in differential scanning calorimetry.” 1991. Web. 20 Apr 2021.
Vancouver:
Thompson M. Matrix effects in differential scanning calorimetry. [Internet] [Doctoral dissertation]. Open University; 1991. [cited 2021 Apr 20].
Available from: http://oro.open.ac.uk/65852/ ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.281223.
Council of Science Editors:
Thompson M. Matrix effects in differential scanning calorimetry. [Doctoral Dissertation]. Open University; 1991. Available from: http://oro.open.ac.uk/65852/ ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.281223
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