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Precise laser alignment in optical cavities is essential for high-precision laser interferometry. We report on a table-top optical experiment featuring two alignment sensing schemes: the conventional Wavefront Sensing (WFS) scheme which…

Instrumentation and Methods for Astrophysics · Physics 2025-10-14 Raed Diab , Alvaro Herrera , Chance Jackson , Paul Fulda

We present a Michelson-type microwave interferometer for use in ferromagnetic resonance experiments. The interferometer is capable of broadband operation without manual adjustment of phase delay or amplitude attenuation. A prototype of the…

Mesoscale and Nanoscale Physics · Physics 2016-11-16 Eric R. J. Edwards , Anthony B. Kos , Mathias Weiler , Thomas J. Silva

In an effort to transcend the limitations of differential imaging of exoplanets in the era of extremely large telescopes (ELTs), the first paper in this series established a rigorous, fully polarimetric framework for determining the science…

Instrumentation and Methods for Astrophysics · Physics 2016-02-18 Richard A. Frazin

Time-of-flight (ToF) 3D imaging has a wealth of applications, from industrial inspection to movement tracking and gesture recognition. Depth information is recovered by measuring the round-trip flight time of laser pulses, which usually…

High-contrast imaging provided by a coronagraph is critical for the direction imaging of the Earth-like planet orbiting its bright parent star. A major limitation for such direct imaging is the speckle noise that is induced from the…

Instrumentation and Methods for Astrophysics · Physics 2015-10-14 JiangPei Dou , DeQing Ren , YongTian Zhu , Xi Zhang

Medical ultrasound provides images which are the spatial map of the tissue echogenicity. Unfortunately, an ultrasound image is a low-quality version of the expected Tissue Reflectivity Function (TRF) mainly due to the non-ideal Point Spread…

Image and Video Processing · Electrical Eng. & Systems 2021-09-28 Sobhan Goudarzi , Hassan Rivaz

This paper presents the work achieved for the manufacturing and characterization of first single-mode waveguides to be used as modal filters for nulling interferometry in the mid-infrared range [4-20 um]. As very high dynamic range is…

Astrophysics · Physics 2009-11-11 L. Labadie , P. Labeye , P. Kern , I. Schanen , B. Arezki , J. -E. Broquin

Conventional spectrometer and polarimeter systems rely on bulky optics, fundamentally limiting compact integration and hindering multi-dimensional optical sensing capabilities. Here, we propose a spectropolarimeter enabled by…

Optics · Physics 2026-04-13 Jumin Qiu , Tingting Liu , Chenxuan Xiang , Tianbao Yu , Qiegen Liu , Shuyuan Xiao

Planar Fourier capture arrays (PFCAs) are optical sensors built entirely in standard microchip manufacturing flows. PFCAs are composed of ensembles of angle sensitive pixels (ASPs) that each report a single coefficient of the Fourier…

Conventional image sensors are only responsive to the intensity variation of the incoming light wave. By encoding the wavefront information into the balanced detection scheme, we demonstrate an image sensor pixel design that is capable to…

Optics · Physics 2013-04-30 Guoan Zheng

Wavefront sensors are an important tool to characterize coherent beams of extreme ultraviolet radiation. However, conventional Hartmann-type sensors do not allow for independent wavefront characterization of different spectral components…

Instrumentation and Detectors · Physics 2018-04-04 L. Freisem , G. S. M. Jansen , D. Rudolf , K. S. E. Eikema , S. Witte

Optical distortions can significantly deteriorate the measurement accuracy in imaging systems. Such distortions can occur at fluctuating phase boundaries as well as multiple-phase flows and result from the accompanied refractive index…

Applied Physics · Physics 2018-02-21 M. Teich , J. Grottke , H. Radner , L. BÜttner , J. W. Czarske

We describe the concept of splitting spatial frequency perturbations into some kind of pupil planes wavefront sensors. Further to the existing approach of dropping higher spatial frequency to suppress aliasing effects (the so-called spatial…

Adaptive optics is a strategy to compensate for sample-induced aberrations in microscopy applications. Generally, it requires the presence of "guide stars" in the sample to serve as localized reference targets. We describe an implementation…

In pulse-echo ultrasound, aberration often degrades image quality when beamforming does not account for wavefront distortions. To address this issue, local sound speed estimators have been developed in the past decade for distributed…

Medical Physics · Physics 2026-05-08 Louise Zhuang , Samuel Beuret , Ben Frey , Saachi Munot , Walter Simson , Dongwoon Hyun , Jeremy J. Dahl

We propose and experimentally demonstrate a fiber spectrum analyzer based on a planar waveguide chip butt-coupled with an input fiber and aligned to a standard camera without any free-space optical elements. The chip consists of a…

Direct detection of exoplanets around nearby stars requires advanced Adaptive Optics (AO) systems. High order systems are needed to reach high Strehl Ratio (SR) in near infrared and optical wavelengths on future Giant Segmented Mirror…

Instrumentation and Methods for Astrophysics · Physics 2024-01-31 C. Vérinaud , C. T. Heritier , M. Kasper , M. Tallon

An inverse source reconstruction (ISR) based 3-D near-field (NF) passive radar microwave imaging method utilizing modulated signals is presented. The modulated signals from a non-cooperative transmitter are scattered by the targets of…

Image and Video Processing · Electrical Eng. & Systems 2026-05-06 Quanfeng Wang , Alexander H. Paulus , Thomas F. Eibert

The large apertures of the upcoming generation of Giant Segmented Mirror Telescopes will enable unprecedented angular resolutions that scale as $\propto$ $\lambda$/D and higher sensitivities that scale as $D^4$ for point sources corrected…

The next generation of Giant Segmented Mirror Telescopes (GSMT) will have large gaps between the segments either caused by the shadow of the mechanical structure of the secondary mirror (E-ELT and TMT) or intrinsically by design (GMT).…