CUDA Framework for Linear Time-Invariant Control of Adaptive Optics Systems

The predictor used here is computed directly from a measured open-loop disturbance sequence using an efficient subspace identification algorithm.

Current science objectives, such as high-contrast imaging of exoplanets, have led to the development of high-order adaptive optics (AO) systems possessing several thousand deformable mirror (DM) actuators. These systems typically rely on integrator-based control architectures, where the temporal error rejection bandwidth is limited by the computational latency between wavefront measurement and application of the DM commands. In many systems, this latency is the driving factor behind residual wavefront error.

Posted in: Briefs, Imaging, Optics, Photonics, Mirrors, Adaptive control, Architecture, Optics

Invertible Time Invariant Linear Filtering (InTILF) Method for Pattern Detection and Modeling of Stochastic One- or Two-Dimensional Data

This tool can analyze and model surface metrology data for polishing-tool fabricators.

X-ray astronomy offers the opportunity to observe important phenomena, including the early accretion of massive black holes and detecting diffuse ionized intergalactic gas that is heated to X-ray temperatures (>106). One of the technical challenges facing X-ray astronomy is fabricating optics that are properly shaped and smooth enough to produce quality images. Surface defects on the order of the wavelength of the observed spectrum and up to the size of the optical surface must be polished out of the mirrors without leaving a detectable pattern because the detectable signal is on the order of magnitude of the noise. This leads to a cycle of polishing and metrology that adds time and expense to optics fabrication.

Posted in: Briefs, Imaging, Photonics, Imaging and visualization, Optics, Fabrication, Radiation

One-Micron (1064-nm) Planar External Cavity Laser (PLANEX)

Ahighly reliable, very low-phase, and low-amplitude-noise laser is required as an oscillator for the LISA mission. A commercial product made by Redfern Integrated Optics met these requirements (1550-nm PLANEX External Cavity Laser), but it operated at 1.5 microns, not the required LISA wavelength of 1 micron. An ultra-low-noise External Cavity Laser was produced at a wavelength of 1 micron, and was integrated in a butterfly package. The goal is to eventually use this laser in the LISA and GRACE-II missions.

Posted in: Briefs, Imaging, Photonics, Lasers, Waveguides, Spacecraft

Stereoscopic Imaging in Hypersonic Boundary Layers Using Planar Laser-Induced Fluorescence

This technique offers a more complete visualization of high-speed flowfields than standard imaging methods.

Stereoscopic time-resolved visualization of three-dimensional structures in a hypersonic flow was performed for the first time in NASA Langley Research Center’s 31-inch Mach 10 Air Tunnel. Nitric oxide (NO) was seeded into hypersonic boundary layer flows that were designed to transition from laminar to turbulent. A laser excitation and multiple-camera imaging scheme was used to obtain raw images containing three-dimensional spatial information. The images were processed in a computer visualization environment to provide stereoscopic image pairs that could be viewed several ways, including using the cross-eyed viewing method, with the aid of a stereoscope, as animated image pairs (i.e., wiggle stereoscopy), or as anaglyph images through conventional red/blue 3D glasses.

Posted in: Briefs, Imaging, Photonics, Computational fluid dynamics, Imaging and visualization, Lasers

Compact, Lightweight, Athermal, Nanocomposite Telescopes with Freeform Optics

Small space missions such as CubeSats frequently require telescopes with highly sophisticated optical systems that are also low in mass and cost. The very limited spacecraft volume and mass limits also preclude adjustments to maintain critical alignment with change in temperature. Existing systems, especially those that employ folded optical paths with freeform optics, are expensive to fabricate. The optics, and support and metering structures, are also heavy due to the use of high-density material such as glass, aluminum, or nickel.

Posted in: Briefs, Imaging, Optics, Photonics, Downsizing, Optics, Nanomaterials, Satellites

CoaXPress Frame Grabber

Responding to the need to create a cost-effective, high-speed interface to fully leverage CXP cameras, BitFlow (Woburn, MA) has introduced the Aon-CXP single link CoaXPress frame grabber. The Aon is powerful enough to support camera speeds up to 6.25 Gigabits/second, which is almost twice as fast as USB3 and over six times the speed of current offerings of GigE Vision. While capturing video at those speeds, it is simultaneously sending control commands, triggers and up to 13 W of power over a single piece of 75 Ohm coaxial cable.

To learn more, click here

Posted in: Products, Data Acquisition, Board-Level Electronics, Computers, Electronics & Computers, Imaging, Video

Scientists Find New Way to Image Solar Cells in 3-D

The Molecular Foundry’s Edward Barnard is part of a team of scientists that developed a new way to see inside solar cells. (Credit: Marilyn Chung)

Next-generation solar cells made of super-thin films of semiconducting material hold promise because they’re relatively inexpensive and flexible enough to be applied just about anywhere. Researchers are working to dramatically increase the efficiency at which thin-film solar cells convert sunlight to electricity. But it’s a tough challenge, partly because a solar cell’s subsurface realm—where much of the energy-conversion action happens—is inaccessible to real-time, nondestructive imaging. It’s difficult to improve processes you can’t see.

Posted in: News, Imaging, Lasers & Laser Systems, Photonics

DIGITAL PATHOLOGY: A Primer for Microscope Camera Selection

Most pathologists today use digital systems within their practices and research projects to communicate, store data, and analyze images. Whether it’s within clinical, forensic, surgical, or other branches of pathology, communication and consultation among specialists is greatly improved by the use of digital systems and enables faster diagnosis for patients.

Posted in: White Papers, Imaging, Medical, Optics, Photonics

Optimizing Next-gen Machine Vision Platform To Enhance Automated Inspection

With machine vision’s development and growth in the Industry 4.0 environment, the higher computing performance becomes essential to acquire high resolution images at high speeds, and expanding FOV (field of view). The associated hardware must therefore significantly enhance reliability, to guarantee smooth operation of the production line. Read this white paper to know more about characteristics the next-gen machine vison platform need.

Posted in: White Papers, Imaging, Manufacturing & Prototyping, Automation, Robotics

Infrared Brings to Light Nanoscale Molecular Arrangement

Detailing the molecular makeup of materials – from solar cells to organic LEDs and transistors to medically important proteins – is not always a crystal-clear process. To understand how materials work at these microscopic scales and to better design materials to improve their function, it's necessary to know not only about their composition but also their molecular arrangement and microscopic imperfections.

Posted in: News, Imaging

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