Sparta, Inc.

Radiation Monitoring Devices, Inc.

Gca Corporation

Sparta Systems, Inc.

Steven A Lis

Philip Dennis Henshaw

Peter M Sienkiewicz

Harvey B Serreze

An improved interferometric measuring system that includes a system for measuring a phase difference between two coherent beams oscillating at substantially the same frequency, and including a phase modulator disposed into optical communication with one of the coherent beams and being adapted to generate a phase modulated beam signal. A beam combiner combines the phase modulated beam signal with the second one of the coherent beams to generate a combined beam signal. A detector element measures the intensity of the combined beam signal and a date processor analyzes the intensity to determine from the harmonic components of the combined beam signal the phase difference between the two coherent beams.

Apparatus and methods employing harmonic analysis for measuring the

An improved interferometric measuring system wherein the system projects a first beam of light at a first measurement wavelength along a reference path to a reference reflector and a second beam of light at a second measurement wavelength along a measurement path to a measurement reflector, and determines a change in position of the measurement reflector from an interference pattern produced between a first light beam reflected from the reference reflector and a second light beam reflected from the measurement reflector, and wherein the system can measure atmospheric disturbances along the measurement path, concurrently with measuring a change in the position of the measurement reflector.

An interferometric measuring system having temperature compensation and

Interferametric measuring system with air turbulence compensation

A multidimensional optical storage medium is provided for storing a plurality of holographic images representative of data. An interrogation network generates a search argument including a target data field to be simultaneously searched for over at least a segment of the optical storage medium. The interrogation network couples the search argument into the optical storage medium and extracts a set of address fields at which data fields in the storage medium that match the target data field of the search argument are stored.

Content addressable optical data storage system

Apparatus for storage and retrieval of digital data includes a multidimensional holographic storage medium for storing phase holographic images representative of the digital data. Selected regions of the medium are independently addressable by a beam of light. The storage medium is a spectral hole burning material having absorption regions independently addressable by selected frequencies of light, and includes selectively bleached absorption structures forming frequency channels. An external electric field of selected voltage can be applied to the storage medium to induce Stark effect broadening of the spectral holes, so that at a given frequency of light, a different phase hologram can be stored for each of a plurality of voltages, whereby multiple phase holograms can be stored for each frequency of light. Alternatively, physical stress can be applied to the storage medium to induce a stress field and associated broadening.

Optical memory method and apparatus utilizing frequency channeling and

Catalytic etching is carried out by placing a pattern of a catalyst on a surface to be selectively etched and treating the imaged surface with an activated fluid which consumes the material being etched. In one embodiment a surface such as a chalcogenide is provided with a silver or other metal pattern corresponding to a semiconductor pattern and the chalcogenide is etched with an oxygen containing plasma reactive with the chalcogenide, the reaction being increased by the silver to provide a positive resist.

Method of catalytic etching

Forming a film by spraying onto a heated substrate an atomized solution containing the appropriate salt of a constituent element of the film and an agent in sufficient amount to change the oxidation state of at least one solute element of the spray solution after contacting the heated substrate.

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Needham, MA, United States of America

Steven A Lis