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Related papers: A 5kHz modulator for pyramid wavefront sensors

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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

The Giant Magellan Telescope (GMT) design consists of seven circular 8.4-m diameter mirror segments that are separated by large > 30 cm gaps, creating the possibility of fluctuations in optical path differences due to flexure, segment…

The controlled modulation of an optical wavefront is required for aberration correction, digital phase conjugation or patterned photostimulation. For most of these applications it is desirable to control the wavefront modulation at the…

Instrumentation and Detectors · Physics 2018-01-09 Maximilian Hoffmann , Ioannis N. Papadopoulos , Benjamin Judkewitz

Wavefront sensing and control are important for enabling one of the key advantages of using large apertures, namely higher angular resolutions. Pyramid wavefront sensors are becoming commonplace in new instrument designs owing to their…

Instrumentation and Methods for Astrophysics · Physics 2019-03-20 Julien Lozi , Nemanja Jovanovic , Olivier Guyon , Mark Chun , Shane Jacobson , Sean Goebel , Frantz Martinache

Almost all current and future high-contrast imaging instruments will use a Pyramid wavefront sensor (PWFS) as a primary or secondary wavefront sensor. The main issue with the PWFS is its nonlinear response to large phase aberrations,…

The active reflector is one of the three main innovations of the Five-hundred-meter Aperture Spherical radio Telescope (FAST). The deformation of such a huge spherically shaped reflector into different transient parabolic shapes is achieved…

Instrumentation and Methods for Astrophysics · Physics 2018-02-08 Hai-Yan Zhang , Ming-Chang Wu , You-Ling Yue , Heng-Qian Gan , Hao Hu , Shi-Jie Huang

MOEMS Deformable Mirrors (DM) are key components for next generation instruments with innovative adaptive optics systems, in existing telescopes and in the future ELTs. These DMs must perform at room temperature as well as in cryogenic and…

Instrumentation and Methods for Astrophysics · Physics 2017-04-19 Frederic Zamkotsian , Patrick Lanzoni , Rudy Barette , Emmanuel Grassi , Patrick Vors , Michael Helmbrecht , Franck Marchis , Alex Teichman

Multimode interference reflectors (MIRs) were recently introduced as a new type of photonic integrated devices for on-chip, broadband light reflection. In the original proposal, different MIRs were demonstrated based on total internal…

Optics · Physics 2015-07-30 Javier S. Fandiño , José D. Doménech , Pascual Muñoz

Segmented, or slow-wave electrodes have emerged as an index-matching solution to improve bandwidth of traveling-wave Mach Zehnder and phase modulators on the thin-film lithium niobate on insulator platform. However, these devices require…

Efficient electro-optic (EO) modulators crucially rely on advanced materials that exhibit strong electro-optic activity and that can be integrated into high-speed and efficient phase shifter structures. In this paper, we demonstrate…

The Thirty Meter Telescope will use a sophisticated adaptive optics system called NFIRAOS. This system utilizes two deformable mirrors conjugate to 0 km and 11.2 km to apply a Multi-Conjugate Adaptive Optics (MCAO) correction over a 2…

Instrumentation and Methods for Astrophysics · Physics 2024-10-17 Mojtaba Taheri , David Andersen , Jean-Pierre Veran , Olivier Lardière

Optical modulators are at the heart of optical communication links. Ideally, they should feature low insertion loss, low drive voltage, large modulation bandwidth, high linearity, compact footprint and low manufacturing cost. Unfortunately,…

A high reflectivity and polarization selective high contrast grating mirror has been designed with the use of an automated optimization algorithm. Through a precise study of the tolerance of the different lengths of the structure, the…

Optical Doppler shift demonstration experiments are not a simple task since the light source cannot usually be moved in a sufficiently smooth and uniform manner to keep the level of noise well below of that of the signal. For that reason…

Physics Education · Physics 2015-06-26 L. Bernal , L. Bilbao

We explore a free-space polarization modulator in which a variable phase introduction between right- and left-handed circular polarization components is used to rotate the linear polarization of the outgoing beam relative to that of the…

Instrumentation and Methods for Astrophysics · Physics 2014-03-24 David T. Chuss , Edward J. Wollack , Giampaolo Pisano , Sheridan Ackiss , Kongpop U-Yen , Ming wah Ng

Broadband electro-optic intensity modulators are essential to convert electrical signals to the optical domain. The growing interest in THz wireless applications demands modulators with frequency responses to the sub-THz range, high power…

A K-mirror is a device that rotates the wavefront of an incident optical field. It has recently gained prominence over Dove prism, another commonly used wavefront rotator, due to the fact that while a K-mirror has several controls for…

Optics · Physics 2024-05-20 Suman Karan , Nilakshi Senapati , Anand K. Jha

For ExAO instruments for the Giant Segmented Mirror Telescopes (GSMTs), alternative architectures of WFS are under consideration because there is a tradeoff between detector size, speed, and noise that reduces the performance of GSMT-ExAO…

We report a Mueller matrix ellipsometer design using dual continuously rotating anisotropic meta wave plates which determines the full set of Mueller matrix elements in the terahertz spectral range. The instrument operates in the frequency…

Instrumentation and Detectors · Physics 2025-03-31 Viktor Rindert , Alexander Ruder , Steffen Richter , Philipp Kühne , Mark Bauer , Vanya Darakchieva , Mathias Schubert

We design a resistive heater optimized for efficient and low-loss optical phase modulation in a silicon-on-insulator (SOI) waveguide and characterize the fabricated devices. Modulation is achieved by flowing current perpendicular to a new…