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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…

Phase imaging techniques extract the optical path-length information of a scene, whereas wavefront sensors provide the shape of an optical wavefront. Since these two applications have different technical requirements, they have developed…

Optics · Physics 2018-02-28 F. Soldevila , V. Durán , P. Clemente , J. Lancis , E. Tajahuerce

Frequency Phase Transfer (FPT) is a technique designed to increase coherence and sensitivity in radio interferometry by making use of the non-dispersive nature of the troposphere to calibrate high-frequency data using solutions derived at a…

We report on amplitude and phase imaging of out-of-plane sinusoidal surface vibration at nanometer scales with a heterodyne holographic interferometer. The originality of the proposed method is to make use of a multiplexed local oscillator…

The two output signals of quadrature phase interferometers allow to benefit both from the high sensitivity of interferometry (working inside a fringe) and from an extended input range (counting fringes). Their calibration to reach a linear…

Instrumentation and Detectors · Physics 2022-09-07 Baptiste Ferrero , Ludovic Bellon

The Large Binocular Telescope Interferometer (LBTI) has the longest baseline in the world, 22.7 m, for performing astronomical interferometry in Fizeau mode, which involves beam combination in a focal plane and preserves a wide…

Instrumentation and Methods for Astrophysics · Physics 2019-08-30 Eckhart Spalding , Phil Hinz , Katie Morzinski , Steve Ertel , Paul Grenz , Erin Maier , Jordan Stone , Amali Vaz

Several types of Wavefront Sensors (WFS) are nowadays available in the field of Adaptive Optics (AO). Generally speaking, their basic principle consists in measuring slopes or curvatures of Wavefront Errors (WFE) transmitted by a telescope,…

Optics · Physics 2011-05-17 Francois Henault

We present a novel way of wavefront sensing using a commercially available, continuous-wave time-of-flight camera with QVGA-resolution. This CMOS phase camera is capable of sensing externally modulated light sources with frequencies up to…

Instrumentation and Detectors · Physics 2021-08-18 Erik Muñiz , Varun Srivastava , Subham Vidyant , Stefan W. Ballmer

This paper deals with the theoretical principle and optical design of a phase-shifting telescope-interferometer. What is called a "Telescope-Interferometer" (T-I) is indeed a novel, recently proposed Wavefront Error (WFE) sensing technique,…

Optics · Physics 2011-05-19 Francois Henault

Phase retrieval is the numerical procedure of recovering a complex-valued signal from knowledge about its amplitude and some additional information. Here, an indirect registration procedure, based on the large deformation diffeomorphic…

Image and Video Processing · Electrical Eng. & Systems 2023-06-29 Erik Malm

A distortion calibration method for wide-angle lens is proposed based on fringe-pattern phase analysis. Firstly, according to the experimental result of the radial distortion of the image not related to the recording depth of field, but…

Image and Video Processing · Electrical Eng. & Systems 2019-11-28 Weishuai Zhou , Jiawen Weng , Junzheng Peng , Jingang Zhong

We report a novel microscopy platform, termed Multi-Aperture Fourier ptychographic microscopy (MA-FPM), capable of realizing gigapixel complex field images with large data acquisition bandwidths - in gigapixels per second. MA-FPM is a…

Optics · Physics 2020-10-14 Pavan Chandra Konda , Jonathan M. Taylor , Andrew R. Harvey

Optical interferometric imaging enables astronomical observation at extremely high angular resolution. The necessary optical information for imaging, such as the optical path differences and visibilities, is easy to extract from fringes…

Fourier ptychography (FP), as a computational imaging method, is a powerful tool to improve imaging resolution. Camera-scanning Fourier ptychography extends the application of FP from micro to macro creatively. Due to the non-ideal scanning…

Image and Video Processing · Electrical Eng. & Systems 2022-06-08 Baiqi Cui , Shaohui Zhang , Yechao Wang , Yao Hu , Qun Hao

One of the major challenges of employing a dual-frequency phase-shifting algorithm for phase retrieval is its sensitivity to noise. Yun et. al [H Yun, B Li, S Zhang. 2017] proposed a dual-frequency method based on the Fourier transform…

Instrumentation and Detectors · Physics 2018-05-23 Minmin Wang , Canlin Zhou , Shuchun Si , Zhenkun Lei , Xiaolei Li , Hui Li , YanJie Li

A novel method nicknamed ELASTIC is proposed for the alignment of multiple-aperture telescopes, in particular segmented telescopes. It only needs the acquisition of two diversity images of an unresolved source, and is based on the…

Instrumentation and Methods for Astrophysics · Physics 2017-08-02 S. Vievard , F. Cassaing , L. M. Mugnier

A fundamental parameter to determine how electromagnetic waves interfere is their relative phase. Therefore, achieving a fine control over it enables a wide range of interferometric applications. Existing phase control methods rely on…

Hyperspectral cameras have recently been miniaturized for operation on lightweight airborne platforms such as UAV or small aircraft. Unlike frame cameras (RGB or Multispectral), many hyperspectral sensors use a linear array or 'push-broom'…

Computer Vision and Pattern Recognition · Computer Science 2024-09-11 Julien Yuuki Burkhard , Jesse Ray Murray Lahaye , Laurent Valentin Jospin , Jan Skaloud

The 2D phase unwrapping problem seeks to recover a phase image from its observation modulo 2$\pi$, and is a crucial step in a variety of imaging applications. In particular, it is one of the most time-consuming steps in the interferometric…

Optimization and Control · Mathematics 2024-01-19 Benjamin Dubois-Taine , Roland Akiki , Alexandre d'Aspremont

The family of multi-plane phase retrieval sensors, such as the curvature and nonlinear curvature wavefront sensors (WFS), contain tip/tilt information embedded in their signals. We have built a nonlinear curvature WFS to study different…

Instrumentation and Methods for Astrophysics · Physics 2026-03-12 Caleb G. Abbott , Justin R. Crepp , Brian Sands