Raytheon Company

Optical Switch Corporation

Daniel P Resler

Terry A Dorschner

William E Hoke

Steven R Collins

Linda A Palmaccio

Irl W Smith

Andrew D W McKie

Robert D O'Shea

Adam F Kelsey

Michael R Benoit

Mark A Leclerc

Amanda J Kirchner

An assembly having a liquid crystal molecule section, a reflector section, disposed on the liquid crystal molecule section, having a stack of dielectric layers having alternating higher and lower indices of refraction; and an array of electrode sections disposed between a pair of the dielectric layers, one of said pair of dielectric layers having a higher index than the other one of said pair of dielectric layers. The electrodes in the array are interdigitated electrode for producing electric fields parallel to the array. The reflector section is disposed between the liquid crystal molecule section and a thermally conductive substrate.

High power adaptive optic system and components therein

A transmissive liquid crystal (LC) control structure comprising: a superstrate () having a first surface () having a GaN HEMT structure disposed thereon to provide a conductor on the first surface of said superstrate; a substrate () having a first surface disposed over and spaced apart from the first surface of said superstrate and having a GaN HEMT structure () disposed thereon to provide a conductor on the first surface of said substrate and wherein the GaN HEMT structure on one of the superstrate and substrate surfaces are patterned into individual electrodes; a polymer network liquid crystal (PNLC) () disposed in the space between the first surface of said superstrate and the first surface of said substrate; and a control circuit coupled to the individual electrodes.

Liquid crystal control structure, tip-tilt-focus optical phased array and high power adaptive optic

Described herein is a liquid crystal (LC) device having Gallium Nitride HEMT electrodes. The Gallium Nitride HEMT electrodes can be grown on a variety of substrates, including but not limited to sapphire, silicon carbide, silicon, fused silica (using a calcium flouride buffer layer), and spinel. Also described is a structure provided from GaN HEMT grown on large area silicon substrates and transferred to another substrate with appropriate properties for OPA devices. Such substrates include, but are not limited to sapphire, silicon carbide, silicon, fused silica (using a calcium fluoride buffer layer), and spinel. The GaN HEMT structure includes an AlN interlayer for improving the mobility of the structure.

Gallium nitride for liquid crystal electrodes

Described herein is a liquid crystal (LC) device having Gallium Nitride HEMT electrodes. The Gallium Nitride HEMT electrodes can be grown on a variety of substrates, including but not limited to sapphire, silicon carbide, silicon, fused silica (using a calcium fluoride buffer layer), and spinel. Also described is a structure provided from GaN HEMT grown on large area silicon substrates and transferred to another substrate with appropriate properties for OPA devices. Such substrates include, but are not limited to sapphire, silicon carbide, silicon, fused silica (using a calcium fluoride buffer layer), and spinel. The GaN HEMT structure includes an AlN interlayer for improving the mobility of the structure.

Described herein are structures and techniques for providing an LC cell having a hermetically sealed cover disposed over a fill hole provided in a superstrate. The superstrate and cover have adhesion layers disposed thereon. Solder is disposed or otherwise provided around the fill hole (e.g. either on the cover or the superstrate or as a separate piece). The cover is then disposed over the fill hole and the solder is reflowed to form the hermetic seal over the fill hole.

Hermetic liquid crystal cell and sealing technique

A method and apparatus for interference lithography utilize a fiber having a cladding region with axially formed holes surrounding a core region. The fiber emits an optical signal to perform interference lithography. A number of alternative variations in the size and arrangement of axially formed holes produces fibers having characteristics particularly adapted for receiving, communicating, and emitting optical signals for interference lithography.

Interference lithography using holey fibers

A practical means for electrically addressing the extremely large number and high density of phase shifters needed for operation of an optical phased-array beam steerer. The array of phase shifters is divided into identical subarrays which completely fill an optical aperture. All subarrays are connected electrically in parallel by electrically interconnecting corresponding electrodes of each subarray. Thus, the number of external electrical leads required for addressing the full array is reduced to the number of phase shifters in a signle subarray.

Optical beam steerer having subaperture addressing

An optical beam phase shifter includes a liquid crystal cell having an optically-transparent common electrode on a first window and a multiplicity of parallel stripe electrodes on the second window. A multiplicity of control signals are applied between the individual stripe electrodes and the common electrode, thereby creating local variations of the refractive index of the liquid crystal molecules, which variations cause differential phase shifts across the cross section of a light beam incident thereon. The control signals are applied to contact pads affixed to an external surface of the liquid crystal cell, which contact pads underlie a plurality of the stripe electrodes. A multiplicity of conductors extend through the second window to couple the control signals to the stripe electrodes. In the first embodiment, the stripe electrodes are optically-transparent, and the incident beam is reflected from the contact pads. In a second embodiment, the stripe electrodes are reflective, and the incident beam is reflected therefrom.

Deflector for an optical beam

An optical time delay unit for use in an optical phased array beam-steering system includes a switchable polarization rotator in conjunction with Brewster plates and mirrors to form electrically-selectable optical paths of different lengths. The switchable polarization rotator is aligned with the optical beam and is responsive to a control signal for varying the polarization of light passing therethrough. The Brewster plates receive the light passing through the first polarization rotator and are transmissive to a first polarization and reflective of a second. The transmissive and reflective paths are of different lengths, and are recombined at a second Brewster plate. The original polarization may be restored by a second polarization rotator. A plurality of time delay units may be cascaded to permit selection from among many paths of various lengths. In a preferred embodiment, the polarization rotators include liquid crystal cells having nematic phase molecules. Optically-transparent electrodes are formed on the cell windows by an ion implantation process. A planar phased array beamforming system comprises a plurality of time delay units, illustratively arranged in a 2-by-2 configuration, wherein each unit is illuminated by a corresponding sector of a single light beam.

Growing community of inventors

Carlisle, MA, United States of America

Daniel P Resler