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Related papers: Holographic laser Doppler ophthalmoscopy

200 papers

Doppler orbitography uses the Doppler shift in a transmitted signal to determine the orbital parameters of satellites including range and range-rate (or radial velocity). We describe two techniques for atmospheric-limited optical Doppler…

Instrumentation and Methods for Astrophysics · Physics 2020-06-09 Benjamin P. Dix-Matthews , Sascha W. Schediwy , David R. Gozzard , Simon Driver , Karl Ulrich Schreibe , Randall Carman , Michael Tobar

Usually, off-axis digital holographic microscopy requires a coherent light source in order to record a full-field hologram. Nevertheless, a LASER-based illumination leads to a non-negligible coherent noise, decreasing then the imaging…

Optics · Physics 2021-11-02 Stephane Perrin , Jonas Kuhn , Christian Depeursinge

Optical imperfections, misalignments, aberrations, and even dust can significantly limit sensitivity in high-contrast imaging systems such as coronagraphs. An upstream deformable mirror (DM) in the pupil can be used to correct or compensate…

Instrumentation and Methods for Astrophysics · Physics 2015-06-15 Johanan L. Codona , Matthew Kenworthy

Fiber imaging bundles are widely used as thin, passive image conduits for miniaturised and endoscopic microscopy, particularly for confocal fluorescence imaging. Holographic microscopy through fiber bundles is more challenging; phase…

Optics · Physics 2020-10-28 Michael R Hughes

The technique of dual modulation Faraday rotation spectroscopy has been applied for near shot-noise limited detection of HO2 at the exit of an atmospheric pressure flow reactor. This was achieved by combining direct current modulation at 51…

Optics · Physics 2015-06-17 Brian Brumfield , Wenting Sun , Yiguang Ju , Gerard Wysocki

Holography is an established technique for measuring the wavefront of optical signals through interferometric combination with a reference wave. Conventionally the integration time of a hologram is limited by the interferometer coherence…

Optics · Physics 2023-12-13 Guillaume Thekkadath , Duncan England , Benjamin Sussman

We discuss nonlinear spectra of selective reflection from high-density rubidium atomic vapor, where the self-broadening of the resonant transition $5S_{1/2}-5P_{3/2}$ dominates over the Doppler width. In the experiments, the hole-burning…

Atomic Physics · Physics 2026-01-16 V. A. Sautenkov , S. A. Saakyan , A. A. Bobrov , B. B. Zelener

The evaluation and monitoring of cells health in the human retina is crucial and follow time course of retinal diseases, detect lesions before irreversible visual loss and to evaluate treatment effects. Towards this goal, a major challenge…

Fundus photography is indispensable for clinical detection and management of eye diseases. Limited image contrast and field of view (FOV) are common limitations of conventional fundus cameras, making it difficult to detect subtle…

The highest three-dimensional (3D) resolution possible in in-vivo retinal imaging is achieved by combining optical coherence tomography (OCT) and adaptive optics (AO). However, this combination brings important limitations, such as small…

Medical Physics · Physics 2020-10-21 Jules Scholler , Kassandra Groux , Kate Grieve , Claude Boccara , Pedro Mecê

Visible light optical coherence tomography (vis-OCT) provides a unique tool for imaging the structure and oxygen metabolism in tissues. However, since it works in the spectral domain, vis-OCT still suffers from noises due to the multiple…

Medical Physics · Physics 2021-12-28 Danlei Qiao , Peng Miao , Ian Rubinoff , Jibo Zhou , John B. Troy , Hao F. Zhang , Shanbao Tong

Experimental control and detection of atoms and molecules often rely on optical transitions between different electronic states. In many cases, substructure such as hyperfine or spin-rotation structure leads to the need for multiple optical…

Atomic Physics · Physics 2021-05-26 Connor M. Holland , Yukai Lu , Lawrence W. Cheuk

Angular resolved digital holography is presented as a technique for real-time characterization of the full optical field (amplitude and phase) of space-division multiplexing components and fibers, here a 6-mode photonic-lantern is…

Inhomogeneities in the refractive index of a biological sample can introduce phase aberrationsin microscopy systems, severely impairing the quality of images. Adaptive optics can be employed to correct for phase aberrations and improve…

Optical imaging of blood flow yields critical functional insights into the circulatory system, but its clinical implementation has typically been limited to shallow depths (~1 millimeter) due to light scattering in biological tissue. Here,…

Medical Physics · Physics 2024-06-25 Yang Zhang , Joshua Olick-Gibson , Karteekeya Sastry , Lihong V. Wang

Second harmonic optical coherence tomography, which uses coherence gating of second-order nonlinear optical response of biological tissues for imaging, is described and demonstrated. Femtosecond laser pulses were used to excite second…

Optics · Physics 2009-11-10 Yi Jiang , Ivan Tomov , Yimin Wang , Zhongping Chen

We report a diffuse Maxwellian illumination scheme for wide-field retinal laser Doppler holography. Inserting an engineered diffuser in the illumination arm transforms a spatially concentrated near-infrared laser focus into an angularly…

This paper presents a computationally efficient method for the detection of optic nerve head in both color fundus and fluorescein angiography images. It involves a combination of Radon transformation and multi-overlapping windows within an…

Medical Physics · Physics 2019-10-03 Reza Pourreza-Shahri , Meysam Tavakoli , Nasser Kehtarnavaz

High-resolution optical imaging methods, such as confocal microscopy and full-field optical coherence tomography, capture flat optical sections of the sample. If the sample is curved, the optical field sections through several sample layers…

Medical Physics · Physics 2020-07-31 Viacheslav Mazlin , Kristina Irsch , Michel Paques , Mathias Fink , Albert Claude Boccara

Digital holography measures the complex optical field and transfer matrix of a device, polarization-diversity is often achieved through spatial multiplexing. We introduce angular multiplexing, to increase flexibility in the optical setup.…