Physical Sciences

A hybrid ocean wind sensor (HOWS) can map ocean vector wind in low to hurricane-level winds, and non-precipitating and precipitating conditions. It can acquire active and passive measurements through a single aperture at two wavelengths, two polarizations, and multiple incidence angles. Its low profile, compact...

PseudoDiversity is a method of recovering the wavefront in a sparse- or segmented-aperture optical system typified by an interferometer or a telescope equipped with an adaptive primary mirror consisting of controllably slightly moveable segments. (PseudoDiversity should not be confused...

A device combines video feeds from multiple cameras to provide wide-field-of-view, high-resolution, stereoscopic video to the user. The prototype under development consists of two camera assemblies, one for each eye. One of these assemblies incorporates a mounting structure with multiple...

A polarization imaging apparatus has shown promise as a prototype of instruments for medical imaging with contrast greater than that achievable by use of non-polarized light. The underlying principles of design and operation are derived from observations that light interacts with tissue ultrastructures that affect...

A relatively simple thermal technique has been proposed to enable detection of bubbles of gas or bulk gas in a tube that is meant to contain a flowing liquid only. In a system in which gas cannot be tolerated, the technique could be used to trigger a shutoff valve downstream of a location...

A method of determining the radio refractivity of the atmosphere as a function of altitude involves processing of data acquired by airborne or mountain-top Global Positioning System (GPS) receivers from particular GPS satellites as those satellites rise above or fall below the horizon....

A laser tracker (LT) is an important coordinate metrology tool that uses laser interferometry to determine precise distances to objects, points, or surfaces defined by an optical reference, such as a retroreflector. A retroreflector is a precision optic consisting of three orthogonal...

Mercury discharge lamps are critical in many trapped ion frequency standard applications. An integrity monitoring system can be implemented using end-of-life signatures observed in operational mercury discharge lamps, making it possible to forecast imminent failure and to take action to mitigate the...

This device is a biasable, submillimeter-wave, balanced mixer fabricated using JPL’s monolithic membrane process — a simplified version of planar membrane technology. The primary target application is instrumentation used for analysis of atmospheric constituents, pressure,...

Do the Russians know something we don’t? In the waning days of 2009, the head of Russia’s federal space agency, Dr. Anatoly Perminov, made huge headlines by telling a Russian radio station that their space agency was contemplating sending a mission to Apophis, an 885-foot (270-meter) asteroid first...

An acousto-optic cryogenic flow sensor (CFS) determines mass flow of cryogens for spacecraft propellant management. The CFS operates unobtrusively in a high-pressure, high-flowrate cryogenic environment to provide measurements for fluid quality as well as mass flow rate. Experimental hardware uses an optical...

A fiber-based laser transmitter has been designed for active remote-sensing spectroscopy. The transmitter uses a master-oscillator- power-amplifier (MOPA) configuration with a distributed feedback diode-laser master oscillator and an erbium-doped fiber amplifier. The...

A method allows combining the functions of a heater and a thermometer in a single device, a thermistor, with minimal temperature read errors. Because thermistors typically have a much smaller thermal mass than the objects they monitor, the thermal...

Further results of research, reported in several previous NASA Tech Briefs articles, were obtained on a mathematical formalism for postinstability motions of a dynamical system characterized by exponential divergences of trajectories leading to chaos (including turbulence).

Multiparallel three-dimensional optical microscopy is a method of forming an approximate three-dimensional image of a microscope sample as a collection of images from different depths through the sample. The imaging apparatus includes a single microscope plus an assembly of beam splitters and...

For the Space Interferometry Mission (SIM) Spectrum Calibration Development Unit (SCDU) testbed, wideband white light is used to simulate starlight. The white light source mount requires extremely stable pointing accuracy ( lights were coupled to a photonic crystal fiber (PCF).