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Related papers: Adaptive Aperture Defocused Digital Speckle Photog…

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Laser speckle, the granular intensity pattern arising from random optical interference, provides a high-dimensional encoding of spectral information that can be exploited for precision metrology. Speckle-based spectrometers have advanced…

We describe a multispeckle dynamic light scattering technique capable of resolving the motion of scattering sites in cases that this motion changes systematically with time. The method is based on the visibility of the speckle pattern…

Soft Condensed Matter · Physics 2007-05-23 R. Bandyopadhyay , A. S. Gittings , S. S. Suh , P. K. Dixon , D. J. Durian

High-dynamic range imaging from space in the visible, aiming in particular at the detection of terrestrial exoplanets, necessitates not only the use of a coronagraph, but also of adaptive optics to correct optical defects in real time.…

Astrophysics · Physics 2008-11-26 Pascal J. Bordé , Wesley A. Traub

Optical spectroscopy plays an essential role across scientific research and industry for non-contact materials analysis1-3, increasingly through in-situ or portable platforms4-6. However, when considering low-light-level applications,…

Phase-sensitive coherent imaging exploits changes in the phases of backscattered light to observe tiny alterations of scattering structures or variations of the refractive index. But moving scatterers or a fluctuating refractive index…

Speckle patterns are used in a broad range of applications including microscopy, imaging, and light-matter interactions. Tailoring speckles' statistics can dramatically enhance their performance in applications. We present an experimental…

I propose a spatial-mode demultiplexing (SPADE) measurement scheme for the far-field imaging of spatially incoherent optical sources. For any object too small to be resolved by direct imaging under the diffraction limit, I show that SPADE…

Optics · Physics 2017-03-01 Mankei Tsang

The theoretical approach to describe the defocusing microscopy technique by U. Agero et al. [Phys. Rev. E {\bf 67}, 051904 (2003)] assumes that the size of the objective lens aperture is infinite. This treatment gives that the intensity at…

The displacement field of an object surface can be measured by using speckle interferometry. This technique is based on the phenomenon of laser speckle and consists in correlating speckle interferograms taken after and before the…

Applied Physics · Physics 2019-03-26 Andrés E. Dolinko , Gustavo E. Galizzi

Multispectral imaging plays an important role in many applications from astronomical imaging, earth observation to biomedical imaging. However, the current technologies are complex with multiple alignment-sensitive components, predetermined…

Optics · Physics 2021-09-17 Sujit Kumar Sahoo , Dongliang Tang , Cuong Dang

Aberrations limit scanning fluorescence microscopy when imaging in scattering materials such as biological tissue. Model-based approaches for adaptive optics take advantage of a computational model of the optical setup. Such models can be…

Optics · Physics 2021-07-07 Ivan Vishniakou , Johannes D. Seelig

Schlieren deflectometry aims at characterizing the deflections undergone by refracted incident light rays at any surface point of a transparent object. For smooth surfaces, each surface location is actually associated with a sparse…

Computer Vision and Pattern Recognition · Computer Science 2012-12-04 Prasad Sudhakar , Laurent Jacques , Xavier Dubois , Philippe Antoine , Luc Joannes

Oblique plane microscopy is a method enabling light-sheet fluorescence imaging through a single microscope objective lens by focusing on a tilted plane within the sample. To focus the fluorescence emitted by the oblique plane on a camera,…

Angular differential imaging (ADI) (Marois et al. 2006) is an observational technique in high contrast imaging where the telescope is used in pupil tracking mode so that the image of the sky rotates with respect to the optical surfaces.…

Earth and Planetary Astrophysics · Physics 2017-11-28 Michael Bottom , Garreth Ruane , Dimitri Mawet

Defocus blur is a common problem in photography. It arises when an image is captured with a wide aperture, resulting in a shallow depth of field. Sometimes it is desired, e.g., in portrait effect. Otherwise, it is a problem from both an…

Computer Vision and Pattern Recognition · Computer Science 2025-02-18 Kunal Swami

Aberrations limit optical systems in many situations, for example when imaging in biological tissue. Machine learning offers novel ways to improve imaging under such conditions by learning inverse models of aberrations. Learning requires…

Optics · Physics 2021-04-30 Ivan Vishniakou , Johannes D. Seelig

We present a novel automatic adaptive aperture photometry algorithm for measuring the total magnitudes of merging galaxies with irregular shapes. First, we use a morphological pattern recognition routine for identifying the shape of an…

Instrumentation and Methods for Astrophysics · Physics 2017-02-08 Jen-Chao Huang , Chorng-Yuan Hwang

Speckle is an intrinsic pattern in optical coherence tomography (OCT) that obscures fine image features and degrades effective resolution. In this study, we propose a numerical speckle reduction method based on the dispersed scatterer model…

Light beams can be characterized by their complex spatial profiles in both intensity and phase. Analogous to time signals, which can be decomposed into multiple orthogonal frequency functions, a light beam can also be decomposed into a set…

Consumer cameras, particularly onboard smartphones and UAVs, are now commonly used as scientific instruments. However, their data processing pipelines are not optimized for quantitative radiometry and their calibration is more complex than…

Instrumentation and Detectors · Physics 2019-06-25 Olivier Burggraaff , Norbert Schmidt , Jaime Zamorano , Klaas Pauly , Sergio Pascual , Carlos Tapia , Evangelos Spyrakos , Frans Snik