Dissertations / Theses: 'Coherence (Optics)'

1

Maleev, Ivan. "Partial coherence and optical vortices." Link to electronic thesis, 2004. http://www.wpi.edu/Pubs/ETD/Available/etd-0713104-021808/.

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Anscombe, Marcel Philip. "Nonlinear optics with atomic coherence." Thesis, Imperial College London, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.404378.

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3

Xu, Weiming. "Offset Optical Coherence Tomography." Miami University / OhioLINK, 2021. http://rave.ohiolink.edu/etdc/view?acc_num=miami1626870603439104.

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Palacios, David M. "An optical vortex coherence filter." Link to electronic thesis, 2004. http://www.wpi.edu/Pubs/ETD/Available/etd-0824104-123434/.

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Thesis (Ph. D.)--Worcester Polytechnic Institute.
Keywords: singularity; vortex; phase; diffraction; interference; nulling; singularities; coherence; dislocation; optical vortex. Includes bibliographical references (p. 123-146).

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Akcay, Avni Ceyhun. "System design and optimization of optical coherence tomography." Doctoral diss., University of Central Florida, 2005. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/3586.

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Optical coherence imaging, including tomography (OCT) and microscopy (OCM), has been a growing research field in biomedical optical imaging in the last decade. In this imaging modality, a broadband light source, thus of short temporal coherence length, is used to perform imaging via interferometry. A challenge in optical coherence imaging, as in any imaging system towards biomedical diagnosis, is the quantification of image quality and optimization of the system components, both a primary focus of this research. We concentrated our efforts on the optimization of the imaging system from two main standpoints: axial point spread function (PSF) and practical steps towards compact low-cost solutions. Up to recently, the criteria for the quality of a system was based on speed of imaging, sensitivity, and particularly axial resolution estimated solely from the full-width at half-maximum (FWHM) of the axial PSF with the common practice of assuming a Gaussian source power spectrum. As part of our work to quantify axial resolution we first brought forth two more metrics unlike FWHM, which accounted for side lobes in the axial PSF caused by irregularities in the shape of the source power spectrum, such as spectral dips. Subsequently, we presented a method where the axial PSF was significantly optimized by suppressing the side lobes occurring because of the irregular shape of the source power spectrum. The optimization was performed through optically shaping the source power spectrum via a programmable spectral shaper, which consequentially led to suppression of spurious structures in the images of a layered specimen. The superiority of the demonstrated approach was in performing reshaping before imaging, thus eliminating the need for post-data acquisition digital signal processing. Importantly, towards the optimization and objective image quality assessment in optical coherence imaging, the impact of source spectral shaping was further analyzed in a task-based assessment method based on statistical decision theory. Two classification tasks, a signal-detection task and a resolution task, were investigated. Results showed that reshaping the source power spectrum was a benefit essentially to the resolution task, as opposed to both the detection and resolution tasks, and the importance of the specimen local variations in index of refraction on the resolution task was demonstrated. Finally, towards the optimization of OCT and OCM for use in clinical settings, we analyzed the detection electronics stage, which is a crucial component of the system that is designed to capture extremely weak interferometric signals in biomedical and biological imaging applications. We designed and tested detection electronics to achieve a compact and low-cost solution for portable imaging units and demonstrated that the design provided an equivalent performance to the commercial lock-in amplifier considering the system sensitivity obtained with both detection schemes.
Ph.D.
Optics and Photonics
Optics

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Apostol, Adela. "COHERENCE PROPERTIES OF OPTICAL NEAR-FIELDS." Doctoral diss., University of Central Florida, 2005. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/2715.

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Next generation photonics-based technologies will ultimately rely on novel materials and devices. For this purpose, phenomena at subwavelength scales are being studied to advance both fundamental knowledge and experimental capabilities. In this dissertation, concepts specific to near-field optics and experimental capabilities specific to near-field microscopy are used to investigate various aspects of the statistical properties of random electromagnetic fields in the vicinity of optically inhomogeneous media which emit or scatter radiation. The properties of such fields are being characterized within the frame of the coherence theory. While successful in describing the far-field properties of optical fields, the fundamental results of the conventional coherence theory disregard the contribution of short-range evanescent waves. Nonetheless, the specific features of random fields at subwavelength distances from interfaces of real media are influenced by the presence of evanescent waves because, in this case, both propagating and nonpropagating components contribute to the detectable properties of the radiation. In our studies, we have fully accounted for both contributions and, as a result, different surface and subsurface characteristics of inhomogeneous media could be explored. We investigated different properties of random optical near-fields which exhibit either Gaussian or non-Gaussian statistics. We have demonstrated that characteristics of optical radiation such as first- and second-order statistics of intensity and the spectral density in the vicinity of random media are all determined by both evanescent waves contribution and the statistical properties of the physical interface. For instance, we quantified the subtle differences which exist between the near- and far-field spectra of radiation and we brought the first experimental evidence that, contrary to the predictions of the conventional coherence theory, the values of coherence length in the near field depend on the distance from the interface and, moreover, they can be smaller than the wavelength of light. The results included in this dissertation demonstrate that the statistical properties of the electromagnetic fields which exist in the close proximity of inhomogeneous media can be used to extract structural information. They also suggest the possibility to adjust the coherence properties of the emitted radiation by modifying the statistical properties of the interfaces. Understanding the random interference phenomena in the near-field could also lead to new possibilities for surface and subsurface diagnostics of inhomogeneous media. In addition, controlling the statistical properties of radiation at subwavelength scales should be of paramount importance in the design of miniaturized optical sources, detectors and sensors.
Ph.D.
Other
Optics and Photonics
Optics

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7

Zuluaga, Andrés Felipe. "Contrast agents for tumor detection with optical coherence tomography /." Digital version accessible at:, 2000. http://wwwlib.umi.com/cr/utexas/main.

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8

Aljasem, Khaled [Verfasser]. "Integrated micro-optics for endoscopic optical coherence tomography / Khaled Aljasem." Freiburg : Universität, Br. : Univ., IMTEK, 2010. http://d-nb.info/1006564373/34.

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9

Anisimov, Petr Mikhailovich. "Quantum coherence phenomena in x-ray optics." [College Station, Tex. : Texas A&M University, 2008. http://hdl.handle.net/1969.1/ETD-TAMU-3039.

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10

Muscat, Sarah. "Optical coherence tomography." Thesis, Connect to e-thesis, 2003. http://theses.gla.ac.uk/630/.

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Thesis (Ph.D.) - University of Glasgow, 2003.
Ph.D. thesis submitted to the Department of Cardiovascular and Medical Sciences, Faculty of Medicine, University of Glasgow, 2003. Includes bibliographical references. Print version also available.

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11

Meemon, Panomsak. "Development of optical coherence tomography for tissue diagnostics." Doctoral diss., University of Central Florida, 2010. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/4558.

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Endoscopic OCT utilizes a special miniature probe in the sample arm to access tubular organs inside the human body, such as the cardiovascular system, the lung, the gastrointestinal tract, the urinary tract, and the breast duct. We present an optical design of a dynamic focus endoscopic probe that is capable of about 4 to 6 micrometers] lateral resolution over a large working distance (i.e. up to 5 mm from the distal end of the probe). The dynamic focus capability allows integration of the endoscopic probe to GD-OCM imaging to achieve high resolution endoscopic tomograms. We envision the future of this developing technology as a solution to high resolution, minimally invasive, depth-resolved imaging of not only structure but also the microvasculature of in vivo biological tissues that will be useful for many clinical applications, such as dermatology, ophthalmology, endoscopy, and cardiology. The technology is also useful for animal study applications, such as the monitoring of an embryo's heart for the development of animal models and monitoring of changes in blood circulation in response to external stimulus in small animal brains.; However, the improvement in imaging speed of FD-OCT comes at the expense of a reduction in sensitivity to slow flow information and hence a reduction in detectable velocity range; 2) A structural ambiguity so-called 'mirror image' in FD-OCT prohibits the use of maximum sensitivity and imaging depth range; 3) The requirement of high lateral resolution to resolve capillary vessels requires the use of an imaging optics with high numerical aperture (NA) that leads to a reduction in depth of focus (DOF) and hence the imaging depth range (i.e. less than 100 microns) unless dynamic focusing is performed. Nevertheless, intrinsic to the mechanism of FD-OCT, dynamic focusing is not possible. In this dissertation, the implementation of PR-DOCT in a high speed swept-source based FD-OCT is investigated and optimized. An acquisition scheme as well as a processing algorithm that effectively extends the detectable velocity dynamic range of the PR-DOCT is presented. The proposed technique increased the overall detectable velocity dynamic range of PR-DOCT by about five times of that achieved by the conventional method. Furthermore, a novel technique of mirror image removal called 'Dual-Detection FD-OCT' (DD-FD-OCT) is presented. One of the advantages of DD-FD-OCT to Doppler imaging is that the full-range signal is achieved without manipulation of the phase relation between consecutive axial lines. Hence the full-range DD-FD-OCT is fully applicable to phase-resolved Doppler detection without a reduction in detectable velocity dynamic range as normally encountered in other full-range techniques. In addition, PR- DOCT can utilize the maximum SNR ratio provided by the full-range capability.; Microvasculature can be found in almost every part of the human body, including the internal organs. Importantly, abnormal changes in microvasculature are usually related to pathological development of the tissue cells. Monitoring of changes in blood flow properties in microvasculature, therefore, provides useful diagnostic information about pathological conditions in biological tissues as exemplified in glaucoma, diabetes, age related macular degeneration, port wine stains, burn-depth, and potentially skin cancer. However, the capillary network is typically only one cell in wall thickness with 5 to 10 microns in diameter and located in the dermis region of skin. Therefore, a non-invasive flow imaging technique that is capable of depth sectioning at high resolution and high speed is demanded. Optical coherence tomography (OCT), particularly after its advancement in frequency domain OCT (FD-OCT), is a promising tool for non-invasive high speed, high resolution, and high sensitivity depth-resolved imaging of biological tissues. Over the last ten years, numerous efforts have been paid to develop OCT-based flow imaging techniques. An important effort is the development of phase-resolved Doppler OCT (PR-DOCT). Phase-resolved Doppler imaging using FD-OCT is particularly of interest because of the direct access to the phase information of the depth profile signal. Furthermore, the high speed capability of FD-OCT is promising for real time flow monitoring as well as 3D flow segmentation applications. However, several challenges need to be addressed; 1) Flow in biological samples exhibits a wide dynamic range of flow velocity caused by, for example, the variation in the flow angles, flow diameters, and functionalities.; This capability is particularly useful for imaging of blood flow that locates deep below the sample surface, such as blood flow at deep posterior human eye and blood vessels network in the dermis region of human skin. Beside high speed and functional imaging capability, another key parameter that will open path for optical diagnostics using OCT technology is high resolution imaging (i.e. in a regime of a few microns or sub-micron). Even though the lateral resolution of OCT can be independently improved by opening the NA of the imaging optics, the high lateral resolution is maintained only over a short range as limited by the depth of focus that varies inversely and quadratically with NA. Recently developed by our group, 'Gabor-Domain Optical Coherence Microscopy' (GD-OCM) is a novel imaging technique capable for invariant resolution of about 2-3 micrometers] over a 2 mm cubic field-of-view. This dissertation details the imaging protocol as well as the automatic data fusion method of GD-OCM developed to render an in-focus high-resolution image throughout the imaging depth of the sample in real time. For the application of absolute flow measurement as an example, the precise information about flow angle is required. GD-OCM provides more precise interpretation of the tissue structures over a large field-of-view, which is necessary for accurate mapping of the flow structure and hence is promising for diagnostic applications particularly when combined with Doppler imaging. Potentially, the ability to perform high resolution OCT imaging inside the human body is useful for many diagnostic applications, such as providing an accurate map for biopsy, guiding surgical and other treatments, monitoring the functional state and/or the post-operative recovery process of internal organs, plaque detection in arteries, and early detection of cancers in the gastrointestinal tract.
ID: 029050978; System requirements: World Wide Web browser and PDF reader.; Mode of access: World Wide Web.; Thesis (Ph.D.)--University of Central Florida, 2010.; Includes bibliographical references (p. 145-154).
Ph.D.
Doctorate
Optics and Photonics

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12

Armstrong, Julian. "Anatomical optical coherence tomography in the human upper airway." University of Western Australia. School of Electrical, Electronic and Computer Engineering, 2007. http://theses.library.uwa.edu.au/adt-WU2007.0022.

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[Truncated abstract] This thesis describes the development, clinical validation and initial application of a technique for taking measurements of the shape and dimensions of the human upper airway, called anatomical optical coherence tomography (aOCT). The technique uses a transparent catheter containing a rotating optical probe which is introduced transnasally and positioned in the airway and oesophagus. Optical coherence tomography is used to take calibrated cross-sectional images of the airway lumen as the probe rotates. The probe can also be advanced or withdrawn within the catheter during scanning to build up three-dimensional information. The catheter remains stationary so that the subject is not aware of the probe motion. The initial application of the system is research into obstructive sleep apnoea (OSA), a serious condition characterized by repetitive collapse of the upper airway during sleep and an independent risk factor for deaths by heart disease, strokes or car accidents. Measurement of upper airway size and shape is important for the investigation of the pathophysiology of OSA, and for the development and assesment of new treatments. . . We have used aOCT to capture three-dimensional data sets of the airway shape from upper oesophagus to the nasal cavity, undertaken measurements of compliance and other airway characteristics, and recorded dynamic airway shape during confirmed sleep apnoea events in a hospital sleep laboratory. We have shown that aOCT generates quantitative, real-time measurements of upper airway size and shape, allowing study over lengthy periods during both sleep and wakefulness. These features should make it useful for study of upper airway behavior to investigate OSA pathophysiology, and aid clinical management and treatment development.

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13

Fleming, Christine P. "Characterization of Cardiac Tissue Using Optical Coherence Tomography." Case Western Reserve University School of Graduate Studies / OhioLINK, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=case1270718628.

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14

Silva, K. K. M. Buddhika Dilusha. "Optical coherence tomography : technology enhancements and novel applications." University of Western Australia. School of Electrical, Electronic and Computer Engineering, 2004. http://theses.library.uwa.edu.au/adt-WU2005.0087.

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In the last fifteen years, a great deal of effort has been put forth, worldwide, for investigating and enhancing various aspects of optical coherence tomography (OCT). This thesis begins with a description of the technique of OCT, and an analysis of its underlying theory. The design and construction of an OCT system is described, with particular emphasis on a novel delay scanning method, and novel signal processing. Application of OCT to non-destructive characterisation of seeds, examination of skin lesions, measurement of fluid flow, and refractive index determination, are then demonstrated. Two technological enhancements to OCT are presented in this thesis. The first, an extended-range Fourier domain optical delay line (FDODL), extends the scan range of the traditional FDODL by a factor of almost 9, by scanning the galvanometer mirror around the region of zero tilt-angle. Polarisation optics are used to prevent light coupling back into the interferometer after only a single pass through the FDODL. A non-coplanar version of the FDODL is also presented, which overcomes the losses associated with the polarisation-based design, but trades off scan range to do so. Both versions of FDODL demonstrated excellent linearity and scan uniformity. The second technology presented here, bifocal optical coherence refractometry (BOCR), affords OCT the ability to measure refractive indices within turbid media. It achieves this by generating two confocal gates within the sample. From knowledge of the system parameters, and measurements of the confocal gate separation, the refractive index within the medium is evaluated to within ±0.01. Refractive index mapping is then demonstrated in a number of turbid samples. Three other applications of OCT are also demonstrated in this thesis. The first is the use of OCT to measure full thickness in lupin seeds. Although OCT could not penetrate the entire thickness of the hull, it is demonstrated that the variation in thickness of the two layers observed with OCT, explained 81% of the variation in thickness of the entire hull measured under a SEM. OCT was then applied, for what is believed to be the first time, in a large scale seed screening program. The second application is a preliminary investigation of the suitability of OCT to aid in the diagnosis of skin lesions. Although our system did not possess sufficient positioning accuracy to enable a direct one-to-one comparison between OCT and histology, a number of correspondences between OCT and histology images were demonstrated. The final application of OCT demonstrated here is a novel phase-locked-loop based demodulation scheme, to perform Doppler OCT. This demodulation scheme demonstrated a dynamic range of 98dB, a velocity range of ±20mm/s, and velocity resolution of 0.5mm/s. Using this system, laminar flow was demonstrated in milk flowing through a capillary tube.

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15

Clemens, James Peter. "Collective spontaneous emission in the framework of quantum trajectory theory /." view abstract or download file of text, 2003. http://wwwlib.umi.com/cr/uoregon/fullcit?p3102158.

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Thesis (Ph. D.)--University of Oregon, 2003.
Typescript. Includes vita and abstract. Includes bibliographical references (leaves 129-135). Also available for download via the World Wide Web; free to University of Oregon users.

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Moazzezi, Mojtaba. "Quantum Coherence Effects Coupled via Plasmons." Thesis, University of North Texas, 2018. https://digital.library.unt.edu/ark:/67531/metadc1404550/.

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This thesis is an attempt at studying quantum coherence effects coupled via plasmons. After introducing the quantum coherence in atomic systems in Chapter 1, we utilize it in Chapter 2 to demonstrate a new technique of detection of motion of single atoms or irons inside an optical cavity. By taking into account the interaction of coherences with surface plasmonic waves excited in metal nanoparticles, we provide a theoretical model along with experimental data in Chapter 3 to describe the modification of Raman spectra near metal nanoparticles. We show in chapter 4 that starting from two emitters, coupled via a plasmonic field, the symmetry breaking occurs, making detectable the simultaneous existence of the fast super-radiance and the slow sub-radiance emission of dye fluorescence near a plasmonic surface. In Chapter 5, we study the photon statistics of a group of emitters coupled via plasmons and by the use of quantum regression theorem, we provide a theoretical model to fully investigate the dependence of photon bunching and anti-bunching effects to the interaction between atoms, fields and surrounding mediums.

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17

Tuten, William Scott. "Anterior Segment Optical Coherence Tomography-Based Phakometry Measurements in Children." The Ohio State University, 2009. http://rave.ohiolink.edu/etdc/view?acc_num=osu1243629782.

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18

Htoon, Han. "Studies on quantum coherence phenomena of self-assembled quantum dots." Access restricted to users with UT Austin EID Full text (PDF) from UMI/Dissertation Abstracts International, 2001. http://wwwlib.umi.com/cr/utexas/fullcit?p3037502.

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19

de, Barros Correia Kyotoku Bernardo. "Applications of optical coherence tomography and advances into a photonic integrated device." Universidade Federal de Pernambuco, 2011. https://repositorio.ufpe.br/handle/123456789/6125.

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Made available in DSpace on 2014-06-12T18:02:18Z (GMT). No. of bitstreams: 2 arquivo5666_1.pdf: 7107729 bytes, checksum: 331daa72875ae82bd7eecdcd35436b14 (MD5) license.txt: 1748 bytes, checksum: 8a4605be74aa9ea9d79846c1fba20a33 (MD5) Previous issue date: 2011
Conselho Nacional de Desenvolvimento Científico e Tecnológico
Tomografia por coerência óptica (OCT) é uma técnica de imageamento não invasiva que usa radiação infravermelho para sondar alguns milímetros the profundidade de um alvo com um resolução de poucos micrômetros. Aqui, nós expomos a base teórica para entender a técnica. O texto cobre as duas variedades de OCT domínio temporal e domínio da frequência e descreve três aplicações da técnica em odontologia: a) Um na avalição the propagação rachaduras em polímeros reforçado com fibra usado em restauração dental; b) O imageamento da sobra de dentina e cavidade pulpar após excavação da dentina, com o propósito de medir a espessura da dentina, e c) uma avaliação clínica da integridade de restaurações dentais. Em todas essa aplicações, OCT gerou imagens marcantes e forneceu informações semiquatitativas sobre a estrura dentária. Com o objetivo de desenvolver um sistema de tomografia óptica integrada em um chip. Nós expomos a base teórica da plataforma de fotônica integrada. Após uma revisão literária, nós descobrimos que não existe espectrômetro integrado com a especificações necessárias para uso em OCT. Nós, então, desenvolvemos um espectrômetro com a características necessárias. Isso foi possível devido a uma nova arquitetura de espectrômetro baseada na combinação de um ressoador em anel e um espectrômetro de grade de difração

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20

Beaudry, Neil A. "Coherence and imaging properties of non-ideal patterned multilayer structures." Diss., The University of Arizona, 2003. http://hdl.handle.net/10150/284329.

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Several topics concerning the imaging properties of patterned multilayer mask structures are addressed. Using the split-step beam propagation method in conjunction with linear systems theory, the reflected electric field from a patterned multilayer structure is calculated. This calculation accounts for the finite thickness of the pattern structure and the angular dependence of the multilayer reflector. A coherence mapping relationship is developed for a patterned multilayer structure placed in the object plane of an optical system. It is shown that both the spatial period of the pattern structure as well as the angular dependence of the multilayer reflector determines when a simulation must include angular dependence in the coherence mapping. If the illumination system is non-telecentric, a spatially dependent variation of the image irradiance occurs over the field of view of the optical system. A source with a finite spectral bandwidth causes a substantial irradiance decrease in the final image, due to the spectral dependence of the multilayer structure. In an effort to analyze the effects of roughness in short-wavelength imaging systems, the theory of speckle in partially coherent imaging systems is expanded to include the effects of a pattern structure, as well as imaging system aberrations. Including a pattern structure causes the partially developed speckle to manifest itself as a line edge roughness (LER) in images printed in a binary photoresist. It is shown that the LER can increase as the system becomes more incoherent. It is also shown that defocus causes LER produced in the image plane to dramatically increase. An iterative algorithm is developed to calculate the reflected electric field from a rough multilayer structure, which uses no first-order phase approximation and includes the effects of diffraction within the structure. The iterative algorithm is used with the coherence theory developed in this dissertation to analyze the imaging properties of a patterned multilayer structure. Including the effects of the multilayer structure and the thick pattern in the simulation results in an increase in LER, a slight shift in the ideal focus position and an asymmetry in LER for off-axis illumination.

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21

Armstrong, Julian. "Anatomical optical coherence tomography in the human upper airway /." Connect to this title, 2006. http://theses.library.uwa.edu.au/adt-WU2007.0022.

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22

Baleine, Erwan. "ON THE USE OF VARIABLE COHERENCE IN INVERSE SCATTERING PROBLEMS." Doctoral diss., University of Central Florida, 2006. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/4114.

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Even though most of the properties of optical fields, such as wavelength, polarization, wavefront curvature or angular spectrum, have been commonly manipulated in a variety of remote sensing procedures, controlling the degree of coherence of light did not find wide applications until recently. Since the emergence of optical coherence tomography, a growing number of scattering techniques have relied on temporal coherence gating which provides efficient target selectivity in a way achieved only by bulky short pulse measurements. The spatial counterpart of temporal coherence, however, has barely been exploited in sensing applications. This dissertation examines, in different scattering regimes, a variety of inverse scattering problems based on variable spatial coherence gating. Within the framework of the radiative transfer theory, this dissertation demonstrates that the short range correlation properties of a medium under test can be recovered by varying the size of the coherence volume of an illuminating beam. Nonetheless, the radiative transfer formalism does not account for long range correlations and current methods for retrieving the correlation function of the complex susceptibility require cumbersome cross-spectral density measurements. Instead, a variable coherence tomographic procedure is proposed where spatial coherence gating is used to probe the structural properties of single scattering media over an extended volume and with a very simple detection system. Enhanced backscattering is a coherent phenomenon that survives strong multiple scattering. The variable coherence tomography approach is extended in this context to diffusive media and it is demonstrated that specific photon trajectories can be selected in order to achieve depth-resolved sensing. Probing the scattering properties of shallow and deeper layers is of considerable interest in biological applications such as diagnosis of skin related diseases. The spatial coherence properties of an illuminating field can be manipulated over dimensions much larger than the wavelength thus providing a large effective sensing area. This is a practical advantage over many near-field microscopic techniques, which offer a spatial resolution beyond the classical diffraction limit but, at the expense of scanning a probe over a large area of a sample which is time consuming, and, sometimes, practically impossible. Taking advantage of the large field of view accessible when using the spatial coherence gating, this dissertation introduces the principle of variable coherence scattering microscopy. In this approach, a subwavelength resolution is achieved from simple far-zone intensity measurements by shaping the degree of spatial coherence of an evanescent field. Furthermore, tomographic techniques based on spatial coherence gating are especially attractive because they rely on simple detection schemes which, in principle, do not require any optical elements such as lenses. To demonstrate this capability, a correlated lensless imaging method is proposed and implemented, where both amplitude and phase information of an object are obtained by varying the degree of spatial coherence of the incident beam. Finally, it should be noted that the idea of using the spatial coherence properties of fields in a tomographic procedure is applicable to any type of electromagnetic radiation. Operating on principles of statistical optics, these sensing procedures can become alternatives for various target detection schemes, cutting-edge microscopies or x-ray imaging methods.
Ph.D.
Other
Optics and Photonics
Optics

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23

Karotki, Aliaksandr. "Simultaneous Two-Photon Absorption of Tetrapyrrolic Molecules: From Femtosecond Coherence Experiments to Photodynamic Therapy." Thesis, Montana State University, 2003. http://etd.lib.montana.edu/etd/2003/karotki/KarotkiA03.pdf.

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Simultaneous two-photon absorption (TPA) in tetrapyrrolic molecules is studied and its applications to two-photon coherence gratings and singlet oxygen generation for photodynamic therapy are demonstrated in this thesis. First ever comprehensive study of TPA properties of tetrapyrrolic molecules is conducted in this work. Two-photon transitions in two key spectral regions, red to green and blue to near-UV (transition wavelengths) are investigated. Physical mechanisms leading to enhancement of TPA cross section in tetrapyrroles are elucidated. Porphyrin molecules with greatly enhanced two-photon cross sections are obtained. Spectral coherence interference gratings are created by means of two-photon excitation with pairs of phase-locked femtosecond pulses in tetrapyrrolic molecules. First, gratings are detected by means of persistent spectral hole burning, which constitutes the first ever demonstration of spectral hole burning by simultaneous absorption of two photons. Next, the gratings are detected in fluorescence spectrum, which we use to study zero-phonon lines and phonon sidebands in two-photon transitions. Application of tetrapyrrolic molecules to two-photon photosensitization of singlet molecular oxygen is investigated. First, TPA properties of some known one-photon photosensitizers are investigated. Then, a new class of TPA based photosensitizers with greatly enhanced two-photon cross sections is developed. The generation of singlet molecular oxygen upon two-photon excitation of the new photosensitizers demonstrated for the first time, which opens up new perspectives for two-photon photodynamic therapy.

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24

Zhang, Yuji. "Coherence properties of supercontinuum generated in highly nonlinear photonic crystal fibers." Thesis, Tufts University, 2015. http://pqdtopen.proquest.com/#viewpdf?dispub=3684584.

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In this dissertation, experimentally measured spectral and coherence evolution of supercontinuum (SC) is presented. Highly nonlinear soft-glass photonic crystal fibers (PCF) were used for SC generation, including lead-silicate (Schott SF6) PCFs of a few different lengths: 10.5 cm, 4.7 mm, and 3.9 mm, and a tellurite PCF of 2.7 cm. The pump is an optical parametric oscillator (OPO) at 1550 nm with pulse energy in the order of nanojoule (nJ) and pulse duration of 105 femtosecond (fs). The coherence of SC was measured using the delayed-pulse method, where the interferometric signal was sent into an optical spectrum analyzer (OSA) and spectral fringes were recorded. By tuning the pump power, power-dependent evolution of spectrum and coherence was obtained. Numerical simulations based on the generalized nonlinear Schrodinger equation (GNLSE) were performed. To match the measured data, the simulated spectral evolution was optimized by iteratively tuning parameters and comparing features. To further match the simulated coherence evolution with the measurement, shot noise and pulse-to-pulse power fluctuation were added in the pump, and the standard deviation of the fluctuation was tuned. Good agreement was obtained between the simulated and the measured spectral evolution, in spite of the unavailability of some physical parameters for simulation. It is demonstrated in principle that, given a measured spectral evolution, the fiber length, and the average power of SC, all other parameters can be determined unambiguously, and the spectral evolution can be reproduced in the simulations. Most importantly, the soliton fission length can be simulated accurately. The spectral evolution using the 4.7- and the 3.9-mm SF6 PCFs shows a pattern dominated by self phase modulation (SPM). This indicates that, these fiber lengths are close to the soliton fission length at the maximum power. The spectral evolution using the 10.5-cm SF6 PCF and the 2.7-cm tellurite PCF shows a soliton-fission-dominated pattern, indicating these lengths are much longer than the soliton fission length at the maximum power. For the coherence evolution using the SF6 PCFs, the simulations and the measurements show qualitative agreement, confirming the association between coherence degradation and soliton fission. For the case of the tellurite PCF, nearly quantitative agreement is shown, and it is shown that the solitonic coherence degrades slower than the overall coherence. Fluctuation of coherence occurs at the regime where the coherence starts to degrade, in the measurement and the simulations of the SF6-PCF case. It is shown that the cause is the pulse-to-pulse power fluctuation in the pump. The pulse-to-pulse stability of spectral intensity is another characterization of SC stability, other than the coherence. It is shown by simulations that these two exhibit different dynamics, and have low correlation.

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25

Lin, Haibo Yu Ping. "Speckle mechanism in holographic optical coherence imaging." Diss., Columbia, Mo. : University of Missouri--Columbia, 2009. http://hdl.handle.net/10355/6184.

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Title from PDF of title page (University of Missouri--Columbia, viewed on Feb 15, 2010). The entire thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file; a non-technical public abstract appears in the public.pdf file. Dissertation advisor: Dr. Ping Yu. Vita. Includes bibliographical references.

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Wang, Zhao. "Intravascular Optical Coherence Tomography Image Analysis." Case Western Reserve University School of Graduate Studies / OhioLINK, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=case1364673682.

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James, Jonathan C. "Imaging systems based on the encoding of optical coherence functions." Diss., Georgia Institute of Technology, 2003. http://hdl.handle.net/1853/15607.

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Cheng, Chung-Chieh. "Propagation of transverse optical coherence in random multiple-scattering media /." view abstract or download file of text, 1999. http://wwwlib.umi.com/cr/uoregon/fullcit?p9955916.

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Thesis (Ph. D.)--University of Oregon, 1999.
Typescript. Includes vita and abstract. Includes bibliographical references (leaves 131-135). Also available for download via the World Wide Web; free to University of Oregon users. Address: http://wwwlib.umi.com/cr/uoregon/fullcit?p9955916.

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Torres, Company Victor. "Coherence in ultrashort light pulses and applications in temporal optics." Doctoral thesis, Universitat de València, 2008. http://hdl.handle.net/10803/10124.

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In the last decades, the generation of lasers delivering pulses with durations in the order of femtosecond has constituted an important research topic for the Physics and Engineering communities. The characteristics of this kind of radiation, i.e., broadband spectrum, enormous temporal resolution, high peak-power with low energy average, potentially high repetition rate and high spatial coherence make it an indispensable tool in order to develop many applications in different fields of science and technology. Ultrafast laser technology is ready to offer real world applications ranging from high-tech, such us high-speed circuit testing and biological imaging, to more industrial applications like quality control. The markets that are already or will be influenced in the near future include industries as telecommunications, automotive, electronics, medical and inspection of consumer goods, to name only a few. In this direction, the so-called Space-Time analogy is an important tool for designing new schemes for ultrashort light pulse processing. It is based on the formal similitude between the diffraction of 1D light beams and the distortion of short light pulses in a first-order dispersive medium. In this Thesis, we have extended this analogy from the fully coherent to the partially coherent and quantum regimes. In the fully coherent regime in particular, we have proposed a new system for the tuning of spectral envelope of a short light pulse without altering the input profile. In addition, we have explained the phenomenon of phase-to-amplitude conversion in terms of the Fresnel images of a phase-only diffraction grating. In the partially coherent regime, we have made use of the optical coherence theory to analyze theoretically the influence of the finite source linewidth optical communication systems, as well as the distortion of optical frequency combs due to the general noise in mode-locked lasers. Alternatively, we have proposed and experimentally verified a technique for arbitrary radio-frequency and microwave waveform generation that operates with incoherent broadband light. Finally, in the quantum regime, we have recognized an analogy between the distortion of entangled photons and partially coherent pulses in dispersive media. This similarity has allowed us to point out that many quantum systems do not really require a two-photon light source, so that their complexity can be greatly reduced.
En las últimas décadas, la generación de haces ópticos pulsados con una duración temporal del orden del pico y femtosegundo ha constituido uno de los temas de investigación más candentes en el ámbito de la Física y la Ingeniería. Los sectores que se benefician o beneficiarán de esta tecnología en un futuro cercano incluyen industrias como telecomunicaciones, automoción, electrónica, diagnóstico médico y control de calidad. Todas las potenciales aplicaciones de los pulsos ultracortos requieren de un procesado y manipulación con extremada precisión en el dominio óptico. En esta dirección, la denominada analogía Espacio-Tiempo constituye una importante herramienta para la adaptación de nuevas técnicas ultrarrápidas, basándose en la similitud formal que existe entre la difracción de haces ópticos y la distorsión de pulsos ultracortos en medios dispersivos.En esta Tesis, se ha extendido esta analogía del caso puramente coherente hasta los regímenes parcialmente coherente y cuántico. En el régimen coherente en particular, se ha propuesto un nuevo sistema para la sintonización del ancho de banda de un pulso ultracorto sin cambiar el perfil espectral. Asimismo, se ha explicado el efecto de conversión de onda continua a radiación pulsada en términos de las imágenes de Fresnel de una red pura de fase. En el régimen parcialmente coherente, se ha utilizado la teoría de la coherencia óptica para analizar teóricamente la influencia del ancho de línea en sistemas ópticos de comunicaciones, así como la distorsión de peines de frecuencia debido al ruido presente en todos los sistemas láser. Por otro lado, se ha propuesto y verificado experimentalmente una técnica que utiliza luz incoherente de banda ancha para le generación de perfiles arbitrarios de señales de microondas. Finalmente, en el régimen cuántico, se ha reconocido una similitud formal entre la distorsión de luz cuántica entrelazada tipo "dos fotones" y los pulsos parcialmente coherentes. Esto ha permitido destacar que muchos sistemas cuánticos actualmente en estudio no necesitan realmente una fuente de dos fotones, por lo que su complejidad puede ser reducida enormemente.

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Liu, Xiaojing. "Optical Coherence Photoacoustic Microscopy (OC-PAM) for Multimodal Imaging." FIU Digital Commons, 2016. http://digitalcommons.fiu.edu/etd/3189.

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Optical coherence tomography (OCT) and Photoacoustic microscopy (PAM) are two noninvasive, high-resolution, three-dimensional, biomedical imaging modalities based on different contrast mechanisms. OCT detects the light backscattered from a biological sample either in the time or spectral domain using an interferometer to form an image. PAM is sensitive to optical absorption by detecting the light-induced acoustic waves to form an image. Due to their complementary contrast mechanisms, OCT and PAM are suitable for being combined to achieve multimodal imaging. In this dissertation, an optical coherence photoacoustic microscopy (OC-PAM) system was developed for in vivo multimodal retinal imaging with a pulsed broadband NIR light source. To test the capabilities of the system on multimodal ophthalmic imaging, the retina of pigmented rats was imaged. The OCT images showed the retinal structures with quality similar to conventional OCT, while the PAM images revealed the distribution of melanin in the retina since the NIR PAM signals are generated mainly from melanin in the posterior segment of the eye. By using the pulsed broadband light source, the OCT image quality highly depends on the pulse-to-pulse stability of the light source without averaging. In addition, laser safety is always a concern for in vivo applications, especially for eye imaging with a pulsed light source. Therefore, a continuous wave (CW) light source is desired for OC-PAM applications. An OC-PAM system using an intensity-modulated CW superluminescent diode was then developed. The system was tested for multimodal imaging the vasculature of a mouse ear in vivo by using Gold Nanorods (GNRs) as contrast agent for PAM, as well as excised porcine eyes ex vivo. Since the quantitative information of the optical properties extracted from the proposed NIR OC-PAM system is potentially able to provide a unique technique to evaluate the existence of melanin and lipofuscin specifically, a phantom study has been conducted and the relationship between image intensity of OCT and PAM was interpreted to represent the relationship between the optical scattering property and optical absorption property. It will be strong evidence for practical application of the proposed NIR OC-PAM system.

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Žurauskas, Mantas. "Advanced systems and methods for collecting accurate data in optical coherence tomography." Thesis, University of Kent, 2014. https://kar.kent.ac.uk/48728/.

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Optical coherence tomography (OCT) has recently emerged as a valuable technique in biomedical research and medical diagnostics. OCT based instruments allow acquisi- tion of high-resolution information about the internal structure of translucent organs and tissues without damaging the object. However, unaccounted object movements reduce the quality of acquired data, particularly in functional imaging and in OCT modalities that rely on continuous monitoring. Therefore there is a need for methods that allow mitigating the negative effects of the object movements on the data quality. In this thesis we present several methods and devices that allow improving the ac- curacy of collected data. First we introduce a novel frequency multiplexing method for OCT, which enables simultaneous measurements using several frequency-encoded channels. By doing so, several parameters are measured in the same time, reducing the time to acquire the data and making the technology less sensitive to object movements. We employed the method to extend the functionality of several OCT modalities. We have applied the multiplexer to enable simultaneous en face time domain OCT imag- ing at different depths. We have demonstrated a polarisation sensitive OCT set-up where different multiplexer channels are employed to perform polarisation sensitive measurements. Furthermore, we have demonstrated how the multiplexer can be applied to extend the sensitivity range in swept source based OCT systems. The experiments presented in this thesis illustrate the flexibility of our new multiplexing method, which has proven useful not only for increasing the accuracy of collected data, but as well for increasing the efficiency in using the light from the object. Alternatively, we have investigated tracking as a way to improve the quality of the OCT data acquired from the moving targets. We have demonstrated a closed-loop tracking based set-up that uses low coherence interferometry to continuously monitor the cardiac dynamics of a Drosophila melanogaster embryo.

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Shelley, Paul H. "Optical low coherence reflectometry for process analysis /." Thesis, Connect to this title online; UW restricted, 1996. http://hdl.handle.net/1773/8666.

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Mok, Kwok-hei. "The characterization of retinal nerve fiber layer thickness in normal, high-tension and normal-tension glaucoma using optical coherence tomography." Click to view the E-thesis via HKUTO, 2005. http://sunzi.lib.hku.hk/hkuto/record/B31381005.

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Wang, Hui. "ULTRA HIGH RESOLUTION AND CONTRAST SENSITIVE OPTICAL COHERENCE TOMOGRAPHY." Case Western Reserve University School of Graduate Studies / OhioLINK, 2008. http://rave.ohiolink.edu/etdc/view?acc_num=case1207178563.

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Thurber, Simonida Rutar. "Optical low coherence reflectometery for morphological characterization of static and dynamic systems /." Thesis, Connect to this title online; UW restricted, 2000. http://hdl.handle.net/1773/8597.

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Adie, Steven G. "Enhancement of contrast in optical coherence tomography : new modes, methods and technology." University of Western Australia. School of Electrical, Electronic and Computer Engineering, 2007. http://theses.library.uwa.edu.au/adt-WU2007.0127.

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This thesis is concerned with exploiting the native optical coherence tomography (OCT) contrast mechanism in new ways and with a new contrast mechanism, in both cases to enhance the information content of the tomographic image. Through experiments in microsphere solutions, we show that static speckle contains information about local particle density when the effective number of scatterers in the OCT resolution volume is less than about five. This potentially provides contrast enhancement in OCT images based on local scatterer density, and we discuss the experimental conditions suited to utilising this in biological tissue. We also describe the corrupting effects of multiple scattering, a ubiquitous phenomenon in OCT, on the information content of the static speckle. Consequently, we detail the development of polarisation-based metrics for characterising multiple scattering in OCT images of solid biological tissues. We exploit a detection scheme used for polarisation-sensitive contrast for a new purpose. We present experiments demonstrating the behaviour of these metrics in liquid phantoms, and in biological tissues, ranging from homogeneous non-birefringent to highly heterogeneous and birefringent samples. We discuss the conditions under which these metrics could be used to characterise the relative contribution of single and multiple scattering and, thus, aid in the study of penetration depth limits in OCT. We present a study of a new contrast mechanism - dynamic elastography which seeks to determine the dynamic mechanical properties of tissues. We present a framework for describing the OCT signal in samples undergoing vibrations, and perform experiments at vibration frequencies in the order of tens to hundreds of Hertz, to confirm the theory, and demonstrate the modes of measurement possible with this technique. These modes of measurement, including acoustic amplitude-sweep and frequency-sweep, could provide new information about the local mechanical properties of a sample. We describe a technological advancement enabling, in principle, measurements of local tissue refractive index contrast much deeper within a sample, than is possible with conventional OCT imaging. The design is based on measurement of the optical path length through tissue filling a fixed-width channel situated at the tip of a needle. The needle design and calibration is presented, as well as measurements of scattering phantoms and various biological tissues. This design potentially enables the use of refractive index-based contrast enhancement in the guidance of breast biopsy procedures.

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Lehman, Bret M. "Validation of Optical Coherence Tomography-Based Crystalline Lens Thickness Measurements in Children." The Ohio State University, 2009. http://rave.ohiolink.edu/etdc/view?acc_num=osu1242248244.

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Welch, Gisele Sawaya. "Application of coherence theory to enhanced backscatter and superresovling optical imaging systems." Diss., Georgia Institute of Technology, 1995. http://hdl.handle.net/1853/13705.

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Stensson, Katarina. "Generation and detection of non-classical photon states." Licentiate thesis, KTH, Tillämpad fysik, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-228058.

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This thesis intends to familiarize the reader with the concepts of photon statistics and correlations in quantum optics. Developing light sources that emit quantum states is central for the realization of quantum technologies. One important step in characterizing these sources is the measurement of field fluctuations and correlations, by coincidence measurements. The expectation value of a coincidence measurement, a simultaneous measurement of two intensities (or, more general, four fields), is represented by the fourth-order correlation function. The value of the correlation function, at zero delay between the detection of two photons, reveals important properties of the state to which they belonged, for example the fluctuations of the photon number. Since predictability is important for many applications, light sources emitting single photons are also characterized by the indistinguishability of consecutively emitted photons, or of two photons from separate emitters. In paper I we investigate blinking behaviour in quantum emitters, and its effect on the interference pattern and photon statistics with photons from two separate emitters. Blinking refers to an emitters transition into a non-emitting state, and subsequent transition back to an emitting state. We show that blinking can not be treated as linear loss, when measuring the fourth-order correlation function for two emitters in a Hong-Ou-Mandel setup. In general, a measurement of the fourth-order correlation function is robust to loss, which makes it a very practical tool. However, the relation between recorded coincidence counts and the correlation function is only direct in the limit of zero detection efficiency, and depends on the detection system. In paper II, we show that by adding a variable attenuation in the beam path, we can trace back to the ''true'' value of the correlation function at zero quantum efficiency. This method improves accuracy in correlation measurements by decreasing a systematic error at the expense of an increased statistical error, which is easier to handle, extending the use of coincidence methods to classical and non-classical multi-photon states.

QC 20180517

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Khastehdel, Fumani Ahmad. "QUANTUM CONFINED STATES AND ROOM TEMPERATURE SPIN COHERENCE IN SEMICONDUCTOR NANOCRYSTAL QUANTUM DOTS." Case Western Reserve University School of Graduate Studies / OhioLINK, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=case1449151739.

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Cantor, Ryan Segler. "Sensing array for coherence analysis of modulated aquatic chemical plumes." Thesis, Atlanta, Ga. : Georgia Institute of Technology, 2009. http://hdl.handle.net/1853/28193.

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Chen, Hui. "High resolution laser spectroscopy of cesium and rubidium molecules with optically induced coherence." Texas A&M University, 2006. http://hdl.handle.net/1969.1/4345.

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This work is devoted to the study of the quantum coherent effects in diatomic molecular systems by using high resolution laser spectroscopy. In particular, we have studied the rubidium diatomic molecular gaseous medium's absorption spectrum with high resolution single mode laser spectroscopy. The derived electronic and rotational vibrational constants were used in the backward Raman amplification experiment of Rb diatomic molecule. Both experimental results and theoretical calculation confirms that there is strong backward directionally dependent radiation. This effect can further be utilized in remote detection of chemical material. In the saturated spectroscopy experiment of the cesium diatomic molecule, long-lived ground state coherence was observed. The coherence would decay at a rate less than the natural life time of the excited states, which indicates great possibility for performing the quantum optics experiments previously performed in atomic systems only. Electromagnetically induced transparency has been observed in many atomic systems for many years, while it has been seldom realized in molecular systems. In our experiment of electromagnetically induced transparency in cesium diatomic molecules, we utilized ÃÂ energy levels, and observed subnatural linewidth. This is the first time to realize a ÃÂ type EIT in a molecular ensemble. This experiment will lead to many other experiments of quantum effects in a molecular system, such like magnetic optical rotation, light storage in ensemble of molecules. Magnetically induced chirality in an atomic ensemble is also investigated in my research.

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Thaning, Anna. "Asymptotic methods in design and characterization ofdiffractive axicons." Licentiate thesis, KTH, Microelectronics and Information Technology, IMIT, 2002. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-1473.

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This thesis addresses the subject of diffractive axicons inpartially coherent or oblique illumination. Design andcharacterization of the axicons are performed using asymptoticwave optics, employing the stationary-phase method to obtainapproximations of the diffraction integrals.

A design method for axicons in partially coherentillumination is derived. The method can be applied to anyincident illumination on radially symmetric Schell-model form.It provides analytical solutions for some specific cases, butfor most incident intensity and coherence distributions it canbe solved numerically to yield the desired on-axis intensity.In addition, a method for estimating the width of the focalline is provided. For coherent light, the design method isidentical to the old one based on energy conservation in raybundles. Since the new method is derived entirely from waveoptics, it both clarifies the old method and extends it topartially coherent light.

Oblique illumination of axicons, frequently encountered inapplications, causes degradation of the focal line. This changeis characterized, and from the asymptotic theory it is foundthat the focal line is described by an asteroid curve. Thewidth of the focal segment in oblique illumination isaccurately predicted, as confirmed by simulations andexperiments. It is also found that at a fixed angle, anelliptical axicon may be used to compensate for the adverseeffects of oblique illumination.

Keywords:axicons, diffractive optics, coherence,asymptotic methods

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Albrecht, Daniel J. F. "Electronic Speckle Pattern Interferometry : instruments development, optimisation and applications." Thesis, Loughborough University, 1998. https://dspace.lboro.ac.uk/2134/32474.

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Optical interferometric techniques are being increasingly used in industry. These non contact techniques, using laser methods based on speckle interferometry, assure a greater accuracy in measuring displacements caused by deformations. One such technique, Electronic Speckle Pattern Interferometry (ESPI), has been used successfully, by analysis of the reaction of mechanical components to induced mechanical or thermal stress, for the measurements of in-situ, real time, full-field, in-plane and out-of-plane displacements and the detection of detachments, micro-cracks occurring as internal and external defects.

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Alexander, Annabel. "Investigation of qubit isolation in a rare-earth quantum computer." View electronic text, 2002. http://eprints.anu.edu.au/documents/disk0/00/00/07/61/index.html.

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Thesis (BSc. (Hons))--Australian National University, 2002.
Available via the Australian National University Library Electronic Pre and Post Print Repository. Title from title screen (viewed Mar. 27, 2003). "November, 2002" "A thesis submitted in part fulfillment of the requirements for the degree of Bachelor of Science with Honours, from the Department of Physics, The Australian National University" Includes bibliographical references.

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Blackburn, Brecken June. "DEVELOPMENT OF PHASE DECORRELATION OPTICAL COHERENCE TOMOGRAPHY FOR ASSESSMENT OF THE OCULAR LENS AND CORNEA." Case Western Reserve University School of Graduate Studies / OhioLINK, 2021. http://rave.ohiolink.edu/etdc/view?acc_num=case1629288561842747.

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Acharya, Megha N. "Speckle Reduction in an All Fiber Time Domain Common Path Optical Coherence Tomography by Frame Averaging." University of Akron / OhioLINK, 2012. http://rave.ohiolink.edu/etdc/view?acc_num=akron1353336847.

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Henkel, Carsten. "Coherence theory of atomic de Broglie waves and electromagnetic near fields." Thesis, [S.l. : s.n.], 2004. http://pub.ub.uni-potsdam.de/2004/0027/henkel.pdf.

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Mok, Kwok-hei, and 莫國熙. "The characterization of retinal nerve fiber layer thickness in normal,high-tension and normal-tension glaucoma using optical coherencetomography." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2005. http://hub.hku.hk/bib/B31381005.

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Meiser, Dominic. "Characterization of the coherence of ultra-cold atoms with nonlinear matter wave optics methods." [S.l. : s.n.], 2006. http://nbn-resolving.de/urn:nbn:de:bsz:93-opus-27733.

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Dissertations / Theses on the topic 'Coherence (Optics)'

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