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


Camera-Equipped Vehicles ‘See the Light’ in Cities

Imagine if every police car, bus, and garbage truck gathered important infrastructure data as they made their usual routes through the city.In different field tests around the world, re searchers from the Massachusetts Institute of Technology (Cam bridge, MA) mounted a camera-and-sensor system to the tops of vehicles. As the cars traveled up and down streets, sophisticated software recognized and recorded the presence and strength of street lights. The software estimated pole heights and distinguished between the street lamp’s output and other points of illumination.

Posted in: Articles, Automotive, Optics, Imaging and visualization, Optics, Sensors and actuators, Intelligent transportation systems


Developing a Laser System to Decrease the Rate of Neurodevelopment Issues

A fairly new biomedical imaging modality, optoacoustic imaging is based on the use of laser-generated ultrasound. According to the National Center for Biotechnology Information, it is a hybrid method that has emerged over the past two decades, combining the high-contrast and spectroscopic-based specificity of optical imaging with the high spatial resolution of ultrasound imaging.

Posted in: Articles, Diagnostics, Imaging, Medical, Lasers & Laser Systems, Optics, Imaging and visualization, Lasers, Medical equipment and supplies, Nervous system


Fabricating Optical Mirrors for Use in Outer Space Measurements

There are many ways to manufacture an optic depending on the complexity of the component and the application. From choosing the best substrate, to detailing the numerous operations required to make the optic, all the while considering tight tolerances and other specifications. This article highlights the precision needed to successfully fabricate the mirrors for the Hobby-Eberly Telescope Dark Energy Experiment’s (HETDEX’s) Visible Integral Field Replicable Unit Spectrographs (VIRUS) unit which was designed to measure dark energy in outer space.

Posted in: Application Briefs, Aerospace, Optics, Measuring Instruments, Mirrors, Measurements, Fabrication


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