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Wave front sensing of the surface of equal phase for a propagating electromagnetic wave is a vital technology in fields ranging from real time adaptive optics, to high accuracy metrology, to medical optometry. We have developed a new method…

Optics · Physics 2025-10-01 C. L. Carilli , L. Torino , B. Nikolic , N. Thyagarajan , U. Iriso

In this paper we study a realistic setup for phase retrieval, where the signal of interest is modulated or masked and then for each modulation or mask a diffraction pattern is collected, producing a coded diffraction pattern (CDP) [CLM13].…

Information Theory · Computer Science 2014-03-25 Youssef Mroueh

The state-of-the-art automotive radars employ multidimensional discrete Fourier transforms (DFT) in order to estimate various target parameters. The DFT is implemented using the fast Fourier transform (FFT), at sample and computational…

Signal Processing · Electrical Eng. & Systems 2018-01-16 Shaogang Wang , Vishal M. Patel , Athina Petropulu

Fourier Ptychographic Microscopy (FPM) is an imaging procedure that overcomes the traditional limit on Space-Bandwidth Product (SBP) of conventional microscopes through computational means. It utilizes multiple images captured using a low…

Computer Vision and Pattern Recognition · Computer Science 2022-08-17 Atreyee Saha , Salman S Khan , Sagar Sehrawat , Sanjana S Prabhu , Shanti Bhattacharya , Kaushik Mitra

Here we describe a co-phased 360-degree fringe-projection profilometer which uses 2-projectors and 1-camera and can digitize discontinuous solids with diffuse light surface. This is called co-phased because the two phase demodulated…

Instrumentation and Detectors · Physics 2014-09-15 Manuel Servin , Guillermo Garnica , J. M. Padilla

In powder diffraction data analysis, phase identification is the process of determining the crystalline phases in a sample using its characteristic Bragg peaks. For multiphasic spectra, we must also determine the relative weight fraction of…

Machine Learning · Computer Science 2022-10-21 Patrick Hosein , Jaimie Greasley

Optical two-dimensional Fourier-transformed (2DFT) spectroscopy is used to study the coherent optical response of potassium vapor in a thin transmission cell. Rephasing and non-rephasing spectra of the D1 and D2 transitions are obtained and…

Atomic Physics · Physics 2011-11-29 X. Dai , A. D. Bristow , D. Karaiskaj , S. T. Cundiff

We propose in this work a radar detection system for orthogonal-frequency division multiplexing (OFDM) transmission. We assume that the transmitting antenna Tx is colocated with a monostatic radar. The latter knows the transmitted signal…

Signal Processing · Electrical Eng. & Systems 2023-02-20 Mamady Delamou , Kawtar Zerhouni , Guevara Noubir , El Mehdi Amhoud

Diffusion models, which learn to reverse a signal destruction process to generate new data, typically require the signal at each step to have the same dimension. We argue that, considering the spatial redundancy in image signals, there is…

Machine Learning · Computer Science 2022-11-30 Han Zhang , Ruili Feng , Zhantao Yang , Lianghua Huang , Yu Liu , Yifei Zhang , Yujun Shen , Deli Zhao , Jingren Zhou , Fan Cheng

In present communication, we report our investigations undertaken towards detection of defects and non-destructive evaluation of low-modulus sample of Poly Methyl Metha Acrylate (PMMA) material using phase measuring deflectometry and…

Applied Physics · Physics 2021-07-14 Jitendra Dhanotia , Amit Chatterjee , Vimal Bhatia , Shashi Prakash

Phase is a fundamental resource for optical imaging but cannot be directly observed with intensity measurements. The existing methods to quantify a phase distribution rely on complex devices and structures. Here we experimentally…

Optics · Physics 2020-03-25 Tengfeng Zhu , Junyi Huang , Zhichao Ruan

Diffusion models generate high-quality images but require dozens of forward passes. We introduce Distribution Matching Distillation (DMD), a procedure to transform a diffusion model into a one-step image generator with minimal impact on…

Computer Vision and Pattern Recognition · Computer Science 2024-10-08 Tianwei Yin , Michaël Gharbi , Richard Zhang , Eli Shechtman , Fredo Durand , William T. Freeman , Taesung Park

Machine learning applied to computer vision and signal processing is achieving results comparable to the human brain on specific tasks due to the great improvements brought by the deep neural networks (DNN). The majority of state-of-the-art…

Computer Vision and Pattern Recognition · Computer Science 2020-06-30 José Augusto Stuchi , Levy Boccato , Romis Attux

With the recent commissioning of ground instruments such as SPHERE or GPI and future space observatories like WFIRST-AFTA, coronagraphy should probably become the most efficient tool for identifying and characterizing extra-solar planets in…

Instrumentation and Methods for Astrophysics · Physics 2017-09-11 François Hénault , Alexis Carlotti , Christophe Vérinaud

While 3D point clouds are widely used in vision applications, their irregular and sparse nature make them challenging to handle. In response, numerous encoding approaches have been proposed to capture the rich semantic information of point…

Computer Vision and Pattern Recognition · Computer Science 2026-03-30 Donghyun Kim , Chanyoung Kim , Hyunah Ko , Seong Jae Hwang

Fourier ptychography (FP) is a recently proposed computational imaging technique for high space-bandwidth product imaging. In real setups such as endoscope and transmission electron microscope, the common sample motion largely degrades the…

Optical phase-matching involves establishing a proper phase relationship between the fundamental and generated waves to enable efficient optical parametric processes. It is typically achieved through either birefringence or periodically…

Optics · Physics 2023-05-22 Hao Hong , Chen Huang , Chenjun Ma , Jiajie Qi , Can Liu , Shiwei Wu , Zhipei Sun , Enge Wang , Kaihui Liu

Coherent diffractive imaging (CDI) provides new opportunities for high resolution X-ray imaging with simultaneous amplitude and phase contrast. Extensions to CDI broaden the scope of the technique for use in a wide variety of experimental…

Optics · Physics 2016-01-20 Matthew H. Seaberg , Alexandre d'Aspremont , Joshua J. Turner

Fourier-transform spectroscopy (FTS) has been widely used as a standard analytical technique over the past half-century. FTS is a simple and robust autocorrelation-based technique that is compatible with both temporally coherent and…

Instrumentation and Detectors · Physics 2018-11-21 Kazuki Hashimoto , Takuro Ideguchi

The analysis of signals created by a variety of instruments involves calculating the phase of a sinusoidal type signal. One widely used method to extract this information is through the use of Fourier transforms, but it is known that…

Optics · Physics 2018-11-02 Andrew John Henning , Dawei Tang , Xiangqian , Jiang