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Volume holographic imaging endoscopic design and construction techniquesHowlett, Isela D., Han, Wanglei, Gordon, Michael, Rice, Photini, Barton, Jennifer K., Kostuk, Raymond K. 31 May 2017 (has links)
A reflectance volume holographic imaging (VHI) endoscope has been designed for simultaneous in vivo imaging of surface and subsurface tissue structures. Prior utilization of VHI systems has been limited to ex vivo tissue imaging. The VHI system presented in this work is designed for laparoscopic use. It consists of a probe section that relays light from the tissue sample to a handheld unit that contains the VHI microscope. The probe section is constructed from gradient index (GRIN) lenses that form a 1: 1 relay for image collection. The probe has an outer diameter of 3.8 mm and is capable of achieving 228.1 lp/mm resolution with 660-nm Kohler illumination. The handheld optical section operates with a magnification of 13.9 and a field of view of 390 mu m x 244 mu m. System performance is assessed through imaging of 1951 USAF resolution targets and soft tissue samples. The system has also passed sterilization procedures required for surgical use and has been used in two laparoscopic surgical procedures. (C) 2017 Society of Photo-Optical Instrumentation Engineers (SPIE)
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The determination of surface deformations by holographic-electro-optical processing /Rezai, K. (Khosrow) January 1981 (has links)
No description available.
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Digital Holography for Three Dimensional Tomographic and Topographic MeasurementsWilliams, Logan Andrew 05 June 2014 (has links)
No description available.
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A holographic system that records front-surface detail of a scene moving at high velocityKurtz, Robert L. 20 May 2010 (has links)
It is known that any motion of the scene during the exposure of a hologram results in a spatial modulation of the recorded fringe contrast. On reconstruction this produces a spatial amplitude modulation of the reconstructed wavefront that tends to blur out the image. This paper discusses a novel holographic technique that uses an elliptical orientation for the holographic arrangement. It is shown that the degree of image degradation is not only a function of exposure time but also of the system used. The form of the functional system dependence is given, as well as the results of several systems tested, which verify this dependence. It is further demonstrated that the velocity of the target or the exposure time alone is inconsequential by itself and the important parameter is the total motion of the target Î X = VT. Using the resolution of front-surface detail from a target with a velocity of 17,546 cm/sec, we are able to predict an upper limit on target velocity for resolution of front-surface detail for a given system. / Ph. D.
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Optical studies of micron-scale flows : holographic microscopy, optical trapping and superhydrophobicityBolognesi, Guido 20 January 2012 (has links) (PDF)
Microfluidics is a very recent branch of science and technology. The development and the success, it has had in the last 15 years, is mainly due to the concept of lab-on-a-chip. Those miniaturized devices, integrating one or more laboratory functions, have aroused great interest among several research areas as physics, chemistry, biology and bioengineering. When a fluid is confined in a micro or nano scale structure, its behaviour is strongly affected by its interactions with the surrounding surfaces. In this context, the theme of fluid/solid slippage has been widely studied both theoretically and experimentally. Innovative technologies to enhance the surface slippage by specifically designing the solid interfaces have reportedly demonstrated to be an effective way to reduce the fluid/solid friction. To this end, superhydrophobic surfaces have increasingly attracted the interest of the scientific and technological community thanks to the large wall-slippage they present for liquid water. Though their behaviour has been extensively investigated through several theoretical and numerical methods, the experimental approaches are still indispensable to test and understand the properties of these surfaces. However, the lack of a general predicting model is also due to the fact that no one of the several existing experimental techniques has shown up as a very reliable one. Indeed, the reported measurements of slippage still depends on the specific adopted method, thwarting attempts to corroborate the proposed theoretical and numerical schemes. Therefore, it is evident that a more sensitive and effective experimental technique is still missing. This thesis began and developed inside the wider project of setting up an innovative technique to investigate the fluid-solid slippage on superhydrophobic surfaces by means of optical tweezers. Even though this project is still going on, this work reports the steps performed along the long way towards this main goal and it consists of a collection of several researches involving different scientific fields as optics, microscopy, surface science, microhydrodynamics, microfluidics and microfabrication. The researches presented in this work can be separated in two main categories: i) holographic micromanipulation and microscopy, ii) superhydrophobicity.
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Optical studies of micron-scale flows : holographic microscopy, optical trapping and superhydrophobicity / Etudes optiques des écoulements de fluides à l'échelle micrométrique : microscopie holographique, piégeage optique et superhydrophobieBolognesi, Guido 20 January 2012 (has links)
La microfluidique est une branche récente de la science et de la technologie. Ces quinze dernières années, son développement et son succès ont été principalement dus au concept de labo sur puce (lab-on-a-chip). Ces dispositifs miniaturisés, qu'intègrent plusieurs fonctions de laboratoire, ont été d'un grand intérêt dans différents domaines comme la Physique, la Chimique et la Bio-ingénierie. Lorsque un fluide est confiné dans une structure micro ounanométrique, son comportement est fortement influencé par les interactions avec les surfaces qui l'entourent. Dans ce contexte, la problématique du glissement du fluide sur le solide a été largement étudiée soit théoriquement, soit expérimentalement. Des nouvelles technologies, destinées à augmenter le glissement se sont déjà avérées être une méthode très efficace pour la réduction du frottement fluide/solide. Dans ce contexte, les surfaces superhydrophobes ont sucité l'intérêt de la communauté scientifique et technologique grâce au grand glissement à la paroi qui caractérise ces surfaces. Même si le comportement de ces surfaces a été largement étudié par différentes méthodologies théoriques et numériques, l'approche expérimentale est encore indispensable pour tester et comprendre les propriétés de ces surfaces. Cette thèse a commencé et s'est développée dans un projet plus large qui porte sur la mise en place d'une nouvelle technique pour l'analyse du glissement liquide/solide sur les surfaces superhydrophobes à travers les pièges optiques. Ce manuscrit développe les étapes du projet de recherche qui concernent différents domaines scientifiques comme l'optique, la microscopie, la science des surfaces, la microhydrodynamique, la microfludique et la microfabrication. Les recherches présentées dans cette thèse sont divisées par deux catégories: i) micromanipulation et microscopie holographique, ii) superhydrophobie. / Microfluidics is a very recent branch of science and technology. The development and the success, it has had in the last 15 years, is mainly due to the concept of lab-on-a-chip. Those miniaturized devices, integrating one or more laboratory functions, have aroused great interest among several research areas as physics, chemistry, biology and bioengineering. When a fluid is confined in a micro or nano scale structure, its behaviour is strongly affected by its interactions with the surrounding surfaces. In this context, the theme of fluid/solid slippage has been widely studied both theoretically and experimentally. Innovative technologies to enhance the surface slippage by specifically designing the solid interfaces have reportedly demonstrated to be an effective way to reduce the fluid/solid friction. To this end, superhydrophobic surfaces have increasingly attracted the interest of the scientific and technological community thanks to the large wall-slippage they present for liquid water. Though their behaviour has been extensively investigated through several theoretical and numerical methods, the experimental approaches are still indispensable to test and understand the properties of these surfaces. However, the lack of a general predicting model is also due to the fact that no one of the several existing experimental techniques has shown up as a very reliable one. Indeed, the reported measurements of slippage still depends on the specific adopted method, thwarting attempts to corroborate the proposed theoretical and numerical schemes. Therefore, it is evident that a more sensitive and effective experimental technique is still missing. This thesis began and developed inside the wider project of setting up an innovative technique to investigate the fluid-solid slippage on superhydrophobic surfaces by means of optical tweezers. Even though this project is still going on, this work reports the steps performed along the long way towards this main goal and it consists of a collection of several researches involving different scientific fields as optics, microscopy, surface science, microhydrodynamics, microfluidics and microfabrication. The researches presented in this work can be separated in two main categories: i) holographic micromanipulation and microscopy, ii) superhydrophobicity.
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O método holográfico aplicado em física da matéria condensada /Martins, Pedro Vinícius Fernandes. January 2019 (has links)
Orientador: Luiz Antonio Barreiro / Resumo: O objetivo deste trabalho é apresentar um método alternativo, conhecido em matéria condensada como método holográfico, cuja origem remonta à conhecida dualidade AdS (Espaço anti-d’Sitter) e CFT (Teoria de Campo Conforme). Esse método é especialmente adaptado para resolução de problemas nos quais as partículas encontram-se fortemente ligadas, e que não permitem um tratamento perturbativo usual. Problemas desse tipo aparecem constantemente em atuais fenômenos da física da matéria condensada, como o caso da supercondutividade em “altas temperaturas”. Assim nessa dissertação é considerado um modelo baseado no método holográfico, no qual são incluidos termos não lineares na lagrangeana de interação eletromagnética, cuja origem vem de teoria de cordas bosônicas. Os resultados indicam que existe a possibilidade de se explicar esses materiais supercondutores com alta temperatura crítica. / Abstract: The objective of this work is to present an alternative method, known in condensed matter as a holographic method, whose origin dates back to the well-known AdS (Space Anti-Space) and CFT (Conformal Field Theory) duality. This method is especially adapted for solving problems in which the particles are tightly bound, and which do not allow a usual perturbative treatment. Problems of this type appear constantly in the current phenomena of condensed matter physics, as in the case of superconductivity in "high temperatures". Thus in this dissertation is considered a model based on the holographic method, in which are included non-linear terms in the Lagrangian of electromagnetic interaction, whose origin comes from the theory of bosonic strings. The results indicate that it is possible to explain these superconducting materials at high critical temperature. / Mestre
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Fabrication and Study of the Optical Properties of 3D Photonic Crystals and 2D Graded Photonic Super-CrystalsLowell, David 12 1900 (has links)
In this dissertation, I am presenting my research on the fabrication and simulation of the optical properties of 3D photonic crystals and 2D graded photonic super-crystals. The 3D photonic crystals were fabricated using holographic lithography with a single, custom-built reflective optical element (ROE) and single exposure from a visible light laser. Fully 3D photonic crystals with 4-fold, 5- fold, and 6-fold symmetries were fabricated using the flexible, 3D printed ROE. In addition, novel 2D graded photonic super-crystals were fabricated using a spatial light modulator (SLM) in a 4f setup for pixel-by-pixel phase engineering. The SLM was used to control the phase and intensity of sets of beams to fabricate the 2D photonic crystals in a single exposure. The 2D photonic crystals integrate super-cell periodicities with 4-fold, 5-fold, and 6-fold symmetries and a graded fill fraction. The simulations of the 2D graded photonic super-crystals show extraordinary properties such as full photonic band gaps and cavity modes with Q-factors of ~106. This research could help in the development of organic light emitting diodes, high-efficiency solar cells, and other devices.
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Wavelength Tunable Devices Based on Holographic Polymer Dispersed Liquid CrystalsZhang, Hailiang 29 February 2008 (has links)
No description available.
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Optical Three-Dimensional Image Matching Using Holographic InformationKim, Taegeun 04 September 2000 (has links)
We present a three-dimensional (3-D) optical image matching technique and location extraction techniques of matched 3-D objects for optical pattern recognition. We first describe the 3-D matching technique based on two-pupil optical heterodyne scanning. A hologram of the 3-D reference object is first created and then represented as one pupil function with the other pupil function being a delta function. The superposition of each beam modulated by the two pupils generates a scanning beam pattern. This beam pattern scans the 3-D target object to be recognized. The output of the scanning system gives out the 2-D correlation of the hologram of the reference object and that of the target object. When the 3-D image of the target object is matched with that of the reference object, the output of the system generates a strong correlation peak. This theory of 3-D holographic matching is analyzed in terms of two-pupil optical scanning. Computer simulation and optical experiment results are presented to reinforce the developed theory.
The second part of the research concerns the extraction of the location of a 3-D image matched object. The proposed system basically performs a correlation of the hologram of a 3-D reference object and that of a 3-D target object, and hence 3-D matching is possible. However, the system does not give out the depth location of matched 3-D target objects directly because the correlation of holograms is a 2-D correlation and hence not 3-D shift invariant. We propose two methods to extract the location of matched 3-D objects directly from the correlation output of the system. One method is to use the optical system that focuses the output correlation pattern along depth and arrives at the 3-D location at the focused location. However, this technique has a drawback in that only the location of 3-D targets that are farther away from the 3-D reference object can be extracted. Thus, in this research, we propose another method in which the extraction of a location for a matched 3-D object is possible without the aforementioned drawback. This method applies the Wigner distribution to the power fringe-adjusted filtered correlation output to extract the 3-D location of a matched object. We analyze the proposed method and present computer simulation and optical experiment results. / Ph. D.
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