Hughes Aircraft Company

Paul F Robusto

Michael T Braski

Richard A Tilton

John C Hamacher

Craig P Stephens

William P Bleha

Dwight H Everett

J Samuel Mueller

Stephen J Reinsch

Eliezer Wiener-Avnear

Charles H Wissman

Nobuo J Koda

David D Scofield

Chan H Wang

Paul G Hilton

Harry W Giehll

A method for restricting the mode of operation of long wavelength waveguide laser (FIG. 1) by introducing an approximate step function into the reflectivity of circular optical elements (19) used in such lasers. The preferred method is to grind off a portion of the optical coating (20) of the optical element (19) leaving a circular unground region (26) of high reflectivity having a diameter (D) of approximately 60% of the laser bore width (b) bounded by a ground region (28) of lower reflectivity. The method permits simple, inexpensive field modification of existing lasers.

Method of altering reflectivity of optical elements

A laser array having effectively separate oscillation regions 70,72,74 that are locked in phase is formed with a ceramic body 60,64 having a single, unpartitioned and relatively wide cavity area 62. Effectively isolated separate side by side laser oscillation regions 70,72,74 within the cavity are provided by use of common reflector optics 66,68 on the respective ends of the common cavity, 62 with one of the end optic arrangements comprising a common substrate 100 provided with several separate areas 102,104,106 of high reflectivity, mutually spaced from one another by areas of relatively low reflectivity. Individual control of the several separate regions of laser energy oscillations is provided by employing a separate pair of exciting electrodes 76,78,82,84,88,90 for each such region and applying separate RF exciting signals to the separate pairs respectively. In a large array, whether using plural isolated regions of laser oscillations in a common cavity or plural bores 121,122,123,124,125 separated by intra-cavity partiitons 126,127,128,129, adjustment of exciting power 150,154 to the outer electrode pairs 134,135,142,143 provides frequency correction for distortion and phase de-locking due to transverse thermal gradients.

Phase locked laser array

An RF laser structure (10) is disclosed which includes an elongated laser excitation cavity (27) and an electrode structure (20) for suppressing extraneous RF discharges outside of the laser cavity. The electrode structure includes an electrode (41) adjacent the elongated laser cavity (27) and extending along the laser cavity; a conductive structure (43, 45) adjacent and conductively coupled to the electrodes (41) for shielding the electrode and for providing smooth conductive surfaces; and a dielectric filler (47) encapsulating the electrode and the conductive structure, and for controlling the electric field generated by the electrode structure so that extraneous discharges are suppressed. Also disclosed is a method for making a laser electrode structure which includes the steps of forming an electrode adjacent the elongated laser cavity, and encapsulating the electrodes with a dielectric potting material.

Method of making a laser electrode structure

An RF laser structure (10) is disclosed which includes an elongated laser excitation cavity (27) and an electrode structure (20) for suppressing extraneous RF discharges outside of the laser cavity. The electrode structure includes an electrode (41) adjacent the elongated laser cavity (27) and extending along the laser cavity; a conductive structure (43, 45) adjacent and conductively coupled to the electrode (41) for shielding the electrode and for providing smooth conductive surfaces; and a dielectric filler (47) encapsulating the electrode and the conductive structure, and for controlling the electric field generated by the electrode structure so that extraneous discharges are suppressed. Also disclosed is a method for making a laser electrode structure which includes the steps of forming an electrode adjacent the elongated laser cavity, and encapsulating the electrode with a dielectric potting material.

RF discharge suppression in low pressure gas devices

A compact, full color, light projection system using a liquid crystal light valve (LCLV) and a unique combination of optical devices. The LCLV operates to modulate a light beam which has been polarized by one of the optical devices. The modulated light beam is converged and registered by other optical devices to form the output image.

Liquid crystal light value color projector

A transverse discharge excitation laser is disclosed which includes a dielectric structure (11, 13, 111, 113, 211, 213) for defining an elongated laser excitation cavity (27, 127, 231) suitable for containing a laser gas and maintaining a laser exciting discharge in the laser gas, and further includes opposing conductive electrodes (33, 41, 129, 133, 237, 245) adjacent the laser cavity. The electrodes are sufficiently small to produce a laser exciting discharge within a predetermined region of the laser cavity and to provide optimum efficiency for the desired mode of operation. The electrodes are particularly adjacent opposing walls of the cavity which have a width W, and at least one of the electrodes has a width which is less than the wall width W.

High efficiency RF excited gas laser with transverse discharge excitation

Method of and apparatus for operating an image display system using a hybrid field effect liquid crystal light valve of the type wherein the molecules of the nematic liquid crystal layer are helically twisted through an acute angle. A polarized projection beam is oriented with its polarization direction within the acute twist angle and applied to a reflective face of the light valve. A writing light input image is applied to a photoresponsive opposite face in order to modulate the reflected projection beam. An electric field applied across the light valve is adjusted between two levels to produce either a simultaneous display of multicolor symbology and achromatic (black-white) gray scale images or a separate display of either one of them.

Method of and apparatus for a multimode image display with a liquid

There is disclosed a dielectric reflector for selective wavelength reflection which comprises an alternately deposited series of thin films of silicon and silicon dioxide layers respectively arranged in an alternating sequence of at least one layer of each type of material. This reflector is suitable for use on the reflecting electrode of a liquid crystal video display panel fabricated on a semiconductor substrate. The use of the dielectric reflector in place of other types of reflectors increases the available reflectivity and permits a preselected color or wavelength to be preferentially reflected. The polysilicon layer of the dielectric reflector is doped with p-type or n-type impurities such as boron or phosphorus to make this layer electrically conductive.

Dielectric reflector for selective wavelength reflection

An electrical field sustained conductivity device is fabricated by successively disposing over a layer of cadmium sulfide a film of metal particles and a composite layer of metal particles in an insulating medium. When a potential is applied across the cadmium sulfide layer, an image may be stored therein by momentarily exposing the layer to electrons or light conveying that image. Such exposure introduces conductivity changes in the cadmium sulfide layer by virtue of the layers deposited on it and the conductivity changes are retained so long as the applied potential is maintained.

Growing community of inventors

Carlsbad, CA, United States of America

Paul F Robusto