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Phase shift profilometry has become a standard technique for recording the surface of an object using the projection of sinusoidal patterns. We present a method of projecting the patterns via a pair of single-mode optical fibers mounted…

Optics · Physics 2024-05-16 Steven Johnson , Hal Gee , Faith Nwachi , Simon Peter Mekhail

A recently developed Projection-based Digital Image Correlation (P-DVC) method is here extended to 4D (space and time) displacement field measurement and mechanical identification based on a single radiograph per loading step instead of…

Computational Physics · Physics 2019-05-23 Clément Jailin , Ante Buljac , Amine Bouterf , François Hild , Stéphane Roux

Interferometric imaging is a well established method to image phase objects by mixing the image wavefront with a reference one on a CCD camera. It has also been applied to fast transient phenomena, mostly through the analysis of single…

This paper introduces a novel wavefront sensing approach that relies on the Fourier analysis of a single conventional direct image. In the high Strehl ratio regime, the relation between the phase measured in the Fourier plane and the…

Instrumentation and Methods for Astrophysics · Physics 2015-06-15 Frantz Martinache

Tomography is an imaging technique that works by reconstructing a scene from acquired data in the form of line integrals of the imaging domain. A fundamental underlying assumption in the reconstruction procedure is the precise alignment of…

Numerical Analysis · Mathematics 2018-07-13 Toby Sanders

We present a phase retrieval algorithm for dispersion scan (d-scan), inspired by ptychography, which is capable of characterizing multiple mutually-incoherent ultrafast pulses (or modes) in a pulse train simultaneously from a single d-scan…

Adapting image-pretrained backbones to video typically relies on time-domain adapters tuned to a single temporal scale. Our experiments show that these modules pick up static image cues and very fast flicker changes, while overlooking…

Computer Vision and Pattern Recognition · Computer Science 2026-02-24 Thinesh Thiyakesan Ponbagavathi , Constantin Seibold , Alina Roitberg

We propose a method to address challenges in unconstrained face detection, such as arbitrary pose variations and occlusions. First, a new image feature called Normalized Pixel Difference (NPD) is proposed. NPD feature is computed as the…

Computer Vision and Pattern Recognition · Computer Science 2015-09-08 Shengcai Liao , Anil K. Jain , Stan Z. Li

Matter-wave interferometry is a highly sensitive tool to measure small perturbations in a quantum system. This property allows the creation of precision sensors for dephasing mechanisms such as mechanical vibrations. They are a challenge…

Ptychography promises diffraction limited resolution without the need for high resolution lenses. To achieve high resolution one has to solve the phase problem for many partially overlapping frames. Here we review some of the existing…

Optics · Physics 2012-09-24 C. Yang , J. Qian , A. Schirotzek , F. Maia , S. Marchesini

A simple method for presenting a dynamic transition between Fresnel and Fraunhofer diffraction zones is considered. Experiments are conducted on different apertures and diffraction patterns are photographed at various distances between the…

Active stereovision systems for the 3D measurement of surfaces rely on the sequential projection of different fringe patterns onto the scene to robustly and accurately generate 3D surface data. This limits the temporal resolution to the…

This paper proposes an algorithm based on a staged sliding window Transformer architecture to detect abnormal behaviors in the microstructure of the foreign exchange market, focusing on high-frequency EUR/USD trading data. The method…

Machine Learning · Computer Science 2025-04-02 Qiuliuyang Bao , Jiawei Wang , Hao Gong , Yiwei Zhang , Xiaojun Guo , Hanrui Feng

Entangled-photon coincidence imaging is a method to nonlocally image an object by transmitting a pair of entangled photons through the object and a reference optical system, respectively. The image of the object can be extracted from the…

Quantum Physics · Physics 2016-09-08 Jing Cheng , Shensheng Han

Dispersion curves characterize the frequency dependence of the phase and the group velocities of propagating elastic waves. Many analytical and numerical techniques produce dispersion curves from physics-based models. However, it is often…

Data Analysis, Statistics and Probability · Physics 2021-10-26 V. V. N. Sriram Malladi , Mohammad I. Albakri , Manu Krishnan , Serkan Gugercin , Pablo A. Tarazaga

Event-based image sensors provide microsecond temporal resolution but lack spectral discrimination, whereas diffractive spectral imagers encode wavelength information at conventional frame rates. We introduce a fluorescence microscopy…

Optics · Physics 2026-03-20 Richard G. Baird , Boyden Myers , Erik M. Jorgensen , Rajesh Menon

When subjected to monochromatic incident light a nanoparticle will emit light which then interferes with the incident beam. With sufficient contrast and sufficiently close to the particle this interference pattern may be recorded with a…

Optics · Physics 2019-02-26 T. G. Myers , H. Ribera , W. S. Bacsa

One of the most powerful approaches to imaging at the nanometer or subnanometer length scale is coherent diffraction imaging using X-ray sources. For amorphous (non-crystalline) samples, the raw data can be interpreted as the modulus of the…

Numerical Analysis · Mathematics 2020-04-02 Alexander Barnett , Charles L. Epstein , Leslie Greengard , Jeremy Magland

Image Phase Alignment Super-Sampling (ImPASS) is a computational imaging algorithm for converting a sequence of displaced low-resolution images into a single high-resolution image. The method consists of a unique combination of Phase…

Optics · Physics 2025-09-01 James N. Caron

Even though image signals are typically defined on a regular two-dimensional grid, there also exist many scenarios where this is not the case and the amplitude of the image signal only is available for a non-regular subset of pixel…

Image and Video Processing · Electrical Eng. & Systems 2022-04-28 Jürgen Seiler , Markus Jonscher , Michael Schöberl , André Kaup