Raytheon Company

Terry A Dorschner

Irl W Smith

Douglas S Hobbs

Daniel P Resler

Lawrence J Friedman

Hermann Statz

Michael K Holz

L Q Lambert, Jr

W Michael Lipchak

Wayne H Keene

Steven R Collins

Linda A Palmaccio

James M Howell

Amanda J Kirchner

Vincenzo D Pitruzzella

Irl Wilson Smith, Jr

An optical system capable of routing primary and secondary high power lasers through a blocking switch is described.

High power optical switch

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

A programmable multifunction spectral and/or polarization imager. In one example, such an imager includes an imaging optical subsystem configured to receive electromagnetic radiation from a distant scene, a focal plane array configured to produce an image of the scene, and a programmable polarimetry subsystem electrically switchable between an ON state in which the polarimetry subsystem receives the electromagnetic radiation and provides polarized electromagnetic radiation to the focal plane array, and an OFF state in which the polarimetry system is configured as a first substantially clear aperture that passes the electromagnetic radiation to the focal plane array. In certain examples, the imager includes a programmable spectral imaging sub-system configurable between an ON state and an OFF state.

Multifunction imager

An optical switch () is capable of routing a high-power beam incident at one or more input ports () of the optical switch to either of two or more output ports (), the optical switch comprising: at least one switching stage, each of the at least one switching stages comprising: a switchable high-power liquid crystal (LC) half-wave plate (HWP), oriented with its fast axis at 45&#xb0; to an input polarization direction such that in response to an incident polarized laser beam provided to said switchable high-power liquid crystal, half-wave plate, said HWP acts as a polarization rotator; and a polarizing beam splitter (PBS) disposed in an optical path to intercept light signals output from said switchable high-power liquid crystal (LC) half wave plate (HWP).

A data communication system comprising a plurality of fiber optic cables and a fiber optic switching system, comprising: a support structure for securing light emitting/light receiving ends of the plurality of fiber optic cables in predetermined positions; and, means for re-directing light emitted from the light emitting/light receiving end of one of the fiber optic cables to the light emitting/light receiving ends of one, or more than one, of a plurality of the plurality of fiber optic cables. The re-directing means includes means for collimating and directing the light emitted from the end of one of the cables as a beam propagating along a predetermined direction and for re-directing the beam towards the end of another one of the cables selectively in accordance with an electrical signal. More particularly, the re-directing means includes electro-optical phase shifting medium, preferably liquid crystal molecules.

Optical beam steering system

A ring laser gyro uses a nonplanar path having at least one plane of mirror symmetry and two pathlength control mirrors in order to reduce scatter variations occurring during the operation of the laser gyro. The mirrors used to produce such path are fixed to an isotropic supporting block having passages therein that define the path segments and the mirrors are moved out or in by the expansion or contraction of the block. The two pathlength control mirrors are disposed diagonally opposite each other on the plane of mirror symmetry, and are placed on substrates whose positions are controllable, each substrate being coupled to means for controlling the positions of the substrates as a function of the pathlength. With such a mirror configuration, the pathlength may be held constant by a suitable control means and the relative movement of the mirrors constrains movement, with respect to the mirrors, of the beams circulating in the path to directions perpendicular to the planes of incidence on the mirrors. This causes the beams to sample substantially the same scatter points, normally present on the mirror surfaces, with substantially the same phase throughout the range of movement of the beams.

Diagonal pathlength control

An optical beam steering device for use in a single-aperture laser transceiver system provides deflection of the transmitted and received beams in two planes, while maintaining the distinctive identities of each channel respective to their polarizations. The invention utilizes four single-dimensional beam deflecting devices, two for each orthogonal linear polarization of the two transceiver channels, one of these for each steering axis. In addition, a 90.degree. polarization rotator and a quarter-wave plate are included in the arrangement of beam deflecting devices to satisfy the polarization requirements of these devices and of the transceiver channels. In a preferred embodiment, the beam deflecting devices comprise liquid crystal cells functioning as variable phase retarders, each of the cells comprising a first window having a common electrode, a second window having a multiplicity of electrodes in the form of electrically isolated, parallel stripes, and a layer of liquid crystal molecules intermediate the first and second windows. Means are provided for coupling a multiplicity of control signals individually between the multiplicity of stripe electrodes and the common electrode, thereby creating selectable local variations of refractive index in the liquid crystal layer.

Laser radar system with phased-array beam steerer

An optical beam steering device for use in a single-aperture laser transceiver system provides deflection of the transmitted and received beam in two planes, while maintaining the distinctive identities, of each channel respective to their polarizations. The invention utilizes four single-dimensional beam deflecting devices, two for each orthogonal linear polarization of the two transceiver channels, one of these for each steering axis. In addition, a 90.degree. polarization rotator and a quarter-wave plate are included in the arrangement of beam deflecting devices to satisfy the polarization requirements of these devices and of the transceiver channels. In a preferred embodiment, the beam deflecting devices comprise liquid crystal cells functioning as variable phase retarders, each of the cells comprising a first window having a common electrode, a second window having a multiplicity of electrodes in the form of electrically isolated, parallel stripes, and a layer of liquid crystal molecules intermediate the first and second windows. Means are provided for coupling a multiplicity of control signals individually between the multiplicity of stripe electrodes and the common electrode, thereby creating selectable local variations of refractive index in the liquid crystal layer.

Two-dimensional, phased-array optical beam steerer

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 subdivided into identical subarrays which completely fill an optical aperture. All subarrays are connected electrically in parallel by electrically interconnecting corresponding electrodes of each subarray. Methods are disclosed herein for providing an enhanced number of beam steering positions for the subaperture-addressed beam steerer.

Method for providing beam steering in a subaperture-addressed optical

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

A laser mirror mounting arrangement for a laser formed within a laser body is shown. The mounting arrangement includes a mounting base mounted upon the laser body. A stem is attached to the mounting base to which, in turn, the laser mirror is mounted. The stem has a coefficient of thermal expansion selected to maintain the mirror in a fixed position. This is accomplished by permitting the stem to expand due to thermal expansion in one direction, while the laser body expands due to thermal expansion in the opposite direction.

Passive pathlength control mirror for laser

An optical beam phase shifter includes a liquid crystal cell having a common electrode on a first window and a multiplicity of parallel stripe electrodes on a 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 therebetween, which variations cause differential phase shifts across the cross section of a light beam incident thereon. An optically-refractive element, having an index of refraction greater than the index of refraction of the liquid crystal cell, is interposed between the beam and the liquid crystal cell. The refractive element, illustratively a prism, increases the angle of incidence of the beam entering the cell, thereby increasing the beam travel distance through the liquid crystal molecules. The disclosed structure allows the use of a thinner layer of liquid crystal molecules, and hence, improved response time of the optical beam phase shifter to changes in the control signals, and reduced fringing effects between stripe electrodes.

Growing community of inventors

Newton Centre, MA, United States of America

Terry A Dorschner