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Endoscopic probe optics for spectrally encoded confocal microscopy

Kang, DongKyun; Carruth, Robert W.; Kim, Minkyu; Schlachter, Simon C.; Shishkov, Milen; Woods, Kevin; Tabatabaei, Nima; Wu, Tao; Tearney, Guillermo J.
Fonte: Optical Society of America Publicador: Optical Society of America
Tipo: Artigo de Revista Científica
Publicado em 03/09/2013 EN
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Spectrally encoded confocal microscopy (SECM) is a form of reflectance confocal microscopy that can achieve high imaging speeds using relatively simple probe optics. Previously, the feasibility of conducting large-area SECM imaging of the esophagus in bench top setups has been demonstrated. Challenges remain, however, in translating SECM into a clinically-useable device; the tissue imaging performance should be improved, and the probe size needs to be significantly reduced so that it can fit into luminal organs of interest. In this paper, we report the development of new SECM endoscopic probe optics that addresses these challenges. A custom water-immersion aspheric singlet (NA = 0.5) was developed and used as the objective lens. The water-immersion condition was used to reduce the spherical aberrations and specular reflection from the tissue surface, which enables cellular imaging of the tissue deep below the surface. A custom collimation lens and a small-size grating were used along with the custom aspheric singlet to reduce the probe size. A dual-clad fiber was used to provide both the single- and multi- mode detection modes. The SECM probe optics was made to be 5.85 mm in diameter and 30 mm in length, which is small enough for safe and comfortable endoscopic imaging of the gastrointestinal tract. The lateral resolution was 1.8 and 2.3 µm for the single- and multi- mode detection modes...

6.161 Modern Optics Project Laboratory, Fall 2002; Modern Optics Project Laboratory

Warde, Cardinal
Fonte: MIT - Massachusetts Institute of Technology Publicador: MIT - Massachusetts Institute of Technology
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Lectures, laboratory exercises, and projects in modern optics. Topics: polarization properties of light, reflection and refraction, coherence and interference, Fraunhofer and Fresnel diffraction, imaging and transforming properties of lenses, spatial filtering, coherent optical processors, holography, optical properties of materials, lasers, nonlinear optics, electro-optic and acousto-optic materials and devices, optical detectors, fiber optics, and optical communication. Students may use this subject to find an advanced undergraduate project and/or to satisfy Phase II of the writing requirement.

2.71 Optics, Fall 2001; Optics

Barbastathis, George
Fonte: MIT - Massachusetts Institute of Technology Publicador: MIT - Massachusetts Institute of Technology
EN-US
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Introduction to optical science with elementary engineering applications. Geometrical optics: ray-tracing, aberrations, lens design, apertures and stops, radiometry and photometry. Wave optics: basic electrodynamics, polarization, interference, wave-guiding, Fresnel and Faunhofer diffraction, image formation, resolution, space-bandwidth product. Emphasis on analytical and numerical tools used in optical design. Graduate students are required to complete additional assignments with stronger analytical content, and an advanced design project.

Wavefront sensing and high resolution adaptive optics imaging in the living rodent eye.

Geng, Ying (1982 - ); Williams, David R. ; Greenberg, Kenneth P. ; Schery, Lee Anne
Fonte: University of Rochester Publicador: University of Rochester
Tipo: Tese de Doutorado Formato: Number of Pages:xviii, 142 leaves; Illustrations:ill. (some col.)
ENG
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Thesis (Ph. D.)--University of Rochester. Institute of Optics, 2012.
Chapter 2 co-authored with Kenneth P. Greenberg and others; chapters 3-4 co-authored with Lee Anne Schery and others.; The rodent has become an increasingly valuable model for human diseases and development due to its availability for genetic manipulations. Non-invasive microscopic imaging of the rodent retina would allow tracking of retinal development, disease progression, and the efficacy of therapy in single animals. Correction of the eye’s aberrations using adaptive optics (AO) could improve the resolution of in vivo rodent retinal images, but previous attempts have been limited by the small size of its eye and the difficulty in measuring its aberrations due to poor Shack-Hartmann wavefront sensor (SHWS) spot quality. The work in this thesis describes methods developed to measure the rodent eye optics and to optimize its retinal image quality in vivo. Our first attempt was modifying a confocal fluorescence adaptive optics scanning laser ophthalmoscope (AOSLO) originally built for imaging the primate and human eye to accommodate the rat eye. Despite achieving in vivo resolution sufficient to resolve sub-cellular structures in fluorescent ganglion cells...

Learning related vision problems: abstracts’ book [of the] 1st International Summer School Recent Advances in Ophthalmic Optics and Optometry (OOPT’2012)

Baptista, António M. G., ed. lit.; Costa, Manuel F. M., ed. lit.; International Summer School Recent Advances in Ophthalmic Optics and Optometry, 1, Aveiro, 2012; OOPT’2012
Fonte: Associação de Profissionais Licenciados de Optometria Publicador: Associação de Profissionais Licenciados de Optometria
Tipo: Conferência ou Objeto de Conferência
Publicado em //2012 ENG
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A remarkable development in optometry and ophthalmic optics is taking place in Portugal on last couple decades. The importance of Optometry is now widely recognized in Portugal. A major effort is being undertaken by optometry professionals, students and universities, on the improvement of training and instruction in Optometry. Research on vision sciences in ophthalmic optics and optometry is also fast increasing in Portugal and therefore we are getting into the edge of the remarkable advances in Ophthalmic Optics and Optometry. The Portuguese Association of Graduates in Optometry, APLO, is committed to the development of optometry in Portugal both at professional level and scientific research. The Portuguese Society for Optics and Photonics, SPOF, embraces those goals recognizing the importance of vision sciences and optometry and, in cooperation with other institutions active in the field, will work towards its development. Together we are organizing a high level advanced scientific and technical international training school in Optometry and Ophthalmic Optics. The 1st International Summer School on Advances in Ophthalmic Optics and Optometry is the first of the kind in Portugal and reunites world renowned optometry and ophthalmic optics specialist. This first edition will be focused on “Learning Related Vision Problems” a topic of utmost importance in optometry with remarkable and exciting recent developments that also are going to be presented at the school along with more practical training sessions.

Maritime adaptive optics beam control

Corley, Melissa S.
Fonte: Monterey, California. Naval Postgraduate School Publicador: Monterey, California. Naval Postgraduate School
Formato: xvi, 113 p. : col. ill. ; 28 cm.
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The Navy is interested in developing systems for horizontal, near ocean surface, high-energy laser propagation through the atmosphere. Laser propagation in the maritime environment requires adaptive optics control of aberrations caused by atmospheric distortion. In this research, a multichannel transverse adaptive filter is formulated in Matlab's Simulink environment and compared to a complex lattice filter that has previously been implemented in large system simulations. The adaptive filters are used to augment a classical adaptive optics controller and are also compared to a Kalman filter augmenting a classical controller. Additionally, the Naval Postgraduate School's first laboratory testbed to use adaptive optics for the compensation of atmospheric turbulence is designed and built. The control algorithms are evaluated both in simulation and in the presence of a laboratory-generated disturbance. Finally, effects of horizontal propagation through deep turbulence are created in the lab. Beam control algorithms are tested in this environment to draw initial conclusions about performance in deep turbulence. For the system implemented in this research, the simple transverse filter in combination with a classical proportional-integral controller performs comparably to the complex lattice filter and the Kalman filter in a standard turbulence scenario and demonstrates more robust performance in the deep turbulence scenario. The adaptive optics testbed itself can be transitioned easily between traditional and deep turbulence scenarios and can support a wide range of atmospheric realizations for further beam control research.

Foundation experiments in quantum atom optics with ultracold metastable helium

Manning, Andrew Geoffrey
Fonte: Universidade Nacional da Austrália Publicador: Universidade Nacional da Austrália
Tipo: Thesis (PhD); Doctor of Philosophy (PhD)
EN_AU
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The field of atom optics has progressed rapidly over the past 20 years since the realisation of Bose-Einstein condensation, such that the wave behaviour of atomic gases is now routinely demonstrated. Furthermore, the study of quantum atom optics, which goes beyond a ‘mean-field’ description of quantum systems to consider the behaviour of single particles, has demonstrated both the similarities between photons and massive species, and their differences as a result of the internal structure and external interactions of atoms. An important class of observable quantities which allow such effects to be measured are nth order correlation functions, which can be interpreted as a result of either particle or wave behaviour. These functions provide a statistical description of fluctuations in n-tuples of particles in a source, which rigorously defines concepts such as coherence. The quantum statistics of a Bose-Einstein condensate should be the same as that for an optical laser, while an ideal thermal Bose gas matches the behaviour of incoherent light. However, correlation measurements can also be used to quantify the influence of interactions, dimensionality, confining potentials and waveguides, and the difference in quantum statistics between fermions and bosons...

Nonlinear optics in titanium dioxide: from bulk to integrated optical devices

Evans, Christopher Courtney
Fonte: Harvard University Publicador: Harvard University
Tipo: Thesis or Dissertation
EN_US
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In this thesis, we explore titanium dioxide (TiO2) for ultrafast, on-chip nonlinear optics by studying it in bulk, thin films, and in integrated nonlinear optical devices. TiO2's large nonlinear index of refraction (30 times that of silica) and low two-photon absorption can enable all-optical switching, logic, and wavelength conversion across wavelengths spanning the telecommunications octave (800–1600 nm). In addition, its high linear index of refraction can enhance optical confinement down to nano-scale dimensions and facilitate the tight waveguide bends necessary for dense on-chip integration. Throughout this thesis, we develop TiO2 as a novel on-chip nonlinear optics platform.; Engineering and Applied Sciences

Sliderule-like property of Wigner's little groups and cyclic S-matrices for multilayer optics

Georgieva, Elena; Kim, Y. S.
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
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It is noted that two-by-two S-matrices in multilayer optics can be represented by the Sp(2) group whose algebraic property is the same as the group of Lorentz transformations applicable to two space-like and one time-like dimensions. It is noted also that Wigner's little groups have a sliderule-like property which allows us to perform multiplications by additions. It is shown that these two mathematical properties lead to a cyclic representation of the S-matrix for multilayer optics, as in the case of ABCD matrices for laser cavities. It is therefore possible to write the N-layer S-matrix as a multiplication of the N single-layer S-matrices resulting in the same mathematical expression with one of the parameters multiplied by N. In addition, it is noted, as in the case of lens optics, multilayer optics can serve as an analogue computer for the contraction of Wigner's little groups for internal space-time symmetries of relativistic particles.; Comment: RevTex 13 pages, Secs. IV and V revised and expanded

Wave-optics description of self-healing mechanism in Bessel beams

Aiello, Andrea; Agarwal, Girish S.
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 15/10/2014
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Bessel beams' great importance in optics lies in that these propagate without spreading and can reconstruct themselves behind an obstruction placed across their path. However, a rigorous wave-optics explanation of the latter property is missing. In this work we study the reconstruction mechanism by means of a wave-optics description. We obtain expressions for the minimum distance beyond the obstruction at which the beam reconstructs itself, which are in close agreement with the traditional one determined from geometrical optics. Our results show that the physics underlying the self-healing mechanism can be entirely explained in terms of the propagation of plane waves with radial wave vectors lying on a ring.; Comment: 5 pages, 2 figures. Submitted to Optics Letters

Time-reversed wave mixing in nonlinear optics

Zheng, Yuanlin; Ren, Huaijin; Wan, Wenjie; Chen, Xianfeng
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 14/01/2013
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Time-reversal symmetry is important to optics. In linear optics, a time-reversed process to laser emission enables total absorption of coherent light fields into an optical cavity of loss by time-reversing the original gain medium. In nonlinear optics, time symmetry exists for some well-known processes such as parametric up/down conversion, sum/difference frequency generation, however, combining exact time-reversal symmetry with nonlinear wave mixings is yet explored till now. Here, we demonstrate time reversed wave mixings for second harmonic generation (SHG) and optical parametric amplification (OPA). This enables us to observe the annihilation of coherent beams under time-reversal symmetry by varying the relative phase of the incident fields. Our study offers new avenues for flexible control in nonlinear optics and potential applications in efficient wavelength conversion, all-optical computing.; Comment: 18 pages, 4 figures

Wavelength-Dependent Effects in Maxwell Optics

Khan, Sameen Ahmed
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
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We present a new formalism for light beam optics starting with an exact eight-dimensional matrix representation of the Maxwell equations. The Foldy-Wouthuysen iterative diagonalization technique is employed to obtain a Hamiltonian description for a system with varying refractive index. Besides, reproducing all the traditional quasiparaxial terms, this method leads to additional contributions, which are dependent on the wavelength, in the optical Hamiltonian. This alternate prescription to obtain the aberration expansion is applied to the axially symmetric graded index fiber. This results in the wavelength-dependent modifications of the paraxial behaviour and the aberration coefficients. Furthermore it predicts a wavelength-dependent image rotation. In the low wavelength limit our formalism reproduces the Lie algebraic formalism of optics. The Foldy-Wouthuysen technique employed by us is ideally suited for the Lie algebraic approach to optics. The present study further strengthens the close analogy between the various prescription of light and charged-particle optics. All the associated machinery used in this formalism is described in the text and the accompanying appendices.; Comment: LaTeX 58 pages, corrected eprint numbers in two references...

Analogies between light optics and charged-particle optics

Khan, Sameen Ahmed
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
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The close analogy between geometrical optics and the classical theories of charged-particle beam optics have been known for a very long time. In recent years, quantum theories of charged-particle beam optics have been presented with the very expected feature of wavelength-dependent effects. With the current development of non-traditional prescriptions of Helmholtz and Maxwell optics respectively, accompanied with the wavelength-dependent effects, it is seen that the analogy between the two systems persists. A brief account of the various prescriptions and the parallel of the analogies is presented.; Comment: LaTeX 10 pages, corrected eprint numbers in two references, http://www.pd.infn.it/~khan/ http://www.imsc.ernet.in/~jagan/

Nonlinear transformation optics and engineering of the Kerr effect

Bergamin, Luzi; Alitalo, Pekka; Tretyakov, Sergei
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
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The concept of transformation optics is extended to nonlinear electrodynamics. It is shown that transformation optics favors implicit constitutive relations in terms of energy densities D.E and B.H rather than E^2 and H^2. The Kerr nonlinearity is studied in detail and the transformation optics based engineering of self-interaction effects is discussed. As a specific example we introduce transformation optics applied on a self-focusing field configuration.; Comment: 9 pages, 6 figures, REVTeX; v2: typo in affiliation corrected; v3: final version

Transformation-optics macroscopic visible-light cloaking beyond two dimensions

Chu, Chia-Wei; Zhai, Xiaomin; Lee, Chih Jie; Duan, Yubo; Tsai, Din Ping; Zhang, Baile; Luo, Yuan
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 19/06/2014
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Transformation optics, a recent geometrical design strategy of controlling light by combining Maxwell's principles of electromagnetism with Einstein's general relativity, promises without precedent an invisibility cloaking device that can render a macroscopic object invisible in three dimensions. However, most previous proof-of-concept transformation-optics cloaking devices focused predominantly on two dimensions, whereas detection of a macroscopic object along its third dimension was always unfailing. Here, we report the first experimental demonstration of transformation-optics macroscopic visible-light cloaking beyond two dimensions. This almost-three-dimensional cloak exhibits three-dimensional (3D) invisibility for illumination near its center (i.e. with a limited field of view), and its ideal wide-angle invisibility performance is preserved in multiple two-dimensional (2D) planes intersecting in the 3D space. Both light ray trajectories and optical path lengths have been verified experimentally at the macroscopic scale, which provides unique evidence on the geometrical nature of transformation optics.

Shrinking cloaks in expanding spacetimes: the role of coordinates and the meaning of transformations in Transformation Optics

Thompson, Robert T.; Fathi, Mohsen
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 29/06/2015
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The fully covariant formulation of transformation optics is used to find the configuration of a cloaking device operating in an expanding universe modelled by a Friedmann-Lema\^itre-Robertson-Walker spacetime. This spacetime cloak is used as a platform for probing the covariant formulation of transformation optics, thereby rigorously enhancing the conceptual understanding of the theory. By studying the problem in both comoving and physical coordinates we explicitly demonstrate the preservation of general covariance of electrodynamics under the transformation optics procedure. This platform also enables a detailed study of the various transformations that arise in transformation optics. We define a corporeal transformation as the "transformation" of transformation optics, and distinguish it from coordinate and frame transformations. We find that corporeal transformations considered in the literature have generally been restricted to a subset of all possible corporeal transformations, providing a potential mechanism for increased functionality of transformation optics.; Comment: 24 pages, 4 figures

A Completely Covariant Approach to Transformation Optics

Thompson, Robert T.; Cummer, Steven A.; Frauendiener, Jörg
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
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We show that the Plebanski based approach to transformation optics overlooks some subtleties in the electrodynamics of moving dielectrics that restricts its applicability to a certain class of transformations. An alternative, completely covariant, approach is developed that is more generally applicable and provides a clearer picture of transformation optics.; Comment: 10 pages. This version: Additional references added, corrected a small error in Eq. (28) (Eq. (29) in present version), some revision of the text, appendix content moved to the main body of the text, figure removed. Corresponds more closely to published version. Prepared for a special issue on transformation optics published by Journal of Optics

Transformation Optics and the Geometry of Light

Leonhardt, Ulf; Philbin, Thomas G.
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
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Metamaterials are beginning to transform optics and microwave technology thanks to their versatile properties that, in many cases, can be tailored according to practical needs and desires. Although metamaterials are surely not the answer to all engineering problems, they have inspired a series of significant technological developments and also some imaginative research, because they invite researchers and inventors to dream. Imagine there were no practical limits on the electromagnetic properties of materials. What is possible? And what is not? If there are no practical limits, what are the fundamental limits? Such questions inspire taking a fresh look at the foundations of optics and at connections between optics and other areas of physics. In this article we discuss such a connection, the relationship between optics and general relativity, or, expressed more precisely, between geometrical ideas normally applied in general relativity and the propagation of light, or electromagnetic waves in general, in materials. We also discuss how this connection is applied: in invisibility devices, perfect lenses, the optical Aharonov-Bohm effect of vortices and in analogues of the event horizon.; Comment: 72 pages, 18 figures, preprint with low-resolution images. Introduction to transformation optics...

Entanglement in Classical Optics

Ghose, Partha; Mukherjee, Anirban
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
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The emerging field of entanglement or nonseparability in classical optics is reviewed, and its similarities with and differences from quantum entanglement clearly pointed out through a recapitulation of Hilbert spaces in general, the special restrictions on Hilbert spaces imposed in quantum mechanics and the role of Hilbert spaces in classical polarization optics. The production of Bell-like states in classical polarization optics is discussed, and new theorems are proved to discriminate between separable and nonseparable states in classical wave optics where no discreteness is involved. The influence of the Pancharatnam phase on a classical Bell-like state is deived. Finally, to what extent classical polarization optics can be used to simulate quantum information processing tasks is also discussed. This should be of great practical importance because coherence and entanglement are robust in classical optics but not in quantum systems.; Comment: 27 pages, 13 figures; to be published in Reviews of Theoretical Science; one figure replaced

Integrated optics technology on silicon optical transducers /

Llobera Adan, Andreu
Fonte: Bellaterra : Universitat Autònoma de Barcelona, Publicador: Bellaterra : Universitat Autònoma de Barcelona,
Tipo: Tesis i dissertacions electròniques; info:eu-repo/semantics/doctoralThesis Formato: application/pdf; application/pdf; application/pdf; application/pdf; application/pdf; application/pdf; application/pdf; application/pdf; application/pdf; application/pdf; application/pdf; application/pdf; application/pdf; application/pdf; application/pdf;
Publicado em //2005 ENG; ENG
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Consultable des del TDX; Títol obtingut de la portada digitalitzada; El camp de l'òptica integrada es presenta com un dels mes prometedors a curt-mig plaç degut als clars avantatges que presenta amb respecte de l'electrònica tradicional. El fet d'utilitzar la llum com a medi vehicular, la qual no es veu afectada per les possibles pertorbacions electromagnètiques, entre altres propietats, fan que aquest camp sigui una de les sortides mes viables als greus problemes de congestió de les vies de telecomunicacions que es preveuen en un futur proper. Per altra part, l'ús de l'òptica integrada per a la realització de sensors ofereix unes prestacions superiors a la majoria de transductors actuals: La resistència a condicions hostils, la mesura sense contacte directe i la seguretat en ambients perillosos, fan que aquests siguin de gran interès pel mon industrial. Dels diferents materials aptes per a la realització de components òptics integrats, únicament el silici, amb l'ampli bagatge de processos altament desenvolupats, derivats de la micromecanització i la microelectrònica, permet la fabricació de grans sèries a preus reduïts. Tot i que les propietats òptiques d'aquest element son limitades, la seva abundància, baix preu...