Hughes Aircraft Company

Alexander D Jacobson

Jan Grinberg

Paul O Braatz

Michael Waldner

Donald D Boswell

William P Bleha

Gary D Myer

Kuen Chow

Paul Q Braatz

Donald E Sprotbery

There is disclosed a single crystal silicon charge storage apparatus suitable for use in an alternating current driven liquid crystal light valve having therein a moderately doped microchannel stop grid. The charge storage medium is made of a high resistivity substrate on which an MOS capacitor is formed having fast photoelectric transient response and capable of operating over a wide frequency range. A doped microgrid structure is formed in one side of the substrate to prevent charge carrier spreading at the silicon-silicon dioxide interface and to provide a focusing electric field for the charge carriers. The signal from the substrate is electrically coupled through high-reflectivity mirrors and light blocking layers to the liquid crystal.

High resolution AC silicon MOS-light-valve substrate

A large scale parallel architecture in which many parallel channels numbering 10.sup.2 or more operate simultaneously to create a natural and efficient organization for processing two-dimensional arrays of data. The architecture comprises a plurality of stack integrated circuit wafers having top and bottom surfaces, electric signal paths extending through each of the wafers between the surfaces, and micro-interconnects (smaller than 50 mil) on the surfaces of adjacent wafers interconnecting the respective eletric signal paths with a topographical one-to-one correspondence.

Three-dimensionally structured microelectronic device

High resolution AC silicon MOS light-valve substrate

This invention is directed to a semiconductor structure that includes at least one wafer that is fully depleted of all mobile carriers and is used as a medium for the movement of spatially modulated signal represented by charge carriers through the wafer with a spatial resolution that is smaller than the thickness of the wafer. This may be used in the form of a continuous high resolution silicon photodiode substrate to serve as an image input means for an electro-optical display medium, such as a liquid crystal. Next to the photoactivated substrate is a liquid crystal and next to the crystal is a transparent electrode. The photodiode is reverse biased and both of its sides are depleted of all mobile charges throughout its entire thickness. Thus, charges generated in the substrate move to the display not by diffusion as in prior art devices (e.g. the solid state silicon vidicon) but by the influence of the electric field which tends to minimize their lateral spread and thereby achieves a high spatial resolution in spite of the continuous character of this silicon diode device.

High resolution continuously distributed silicon photodiode substrate

There is disclosed a single crystal silicon charge storage apparatus suitable for use in an alternating current driven liquid crystal light valve having therein a PIN photodiode structure. The charge storage medium is made of a high resistivity substrate on which an MOS capacitor is formed having fast photoelectric transient response an capable of operating over a wide frequency range. A PIN photodiode structure is provided on one side of the substrate next to the MOS capacitor to deplete the substrate of its mobile charge carriers during a portion of the AC cycle and to collect the electric field-guided signal representing charge carriers that are generated or introduced into the substrate by an input mechanism. The signal from the substrate is electrically coupled through high-reflectivity mirrors and light blocking layers to the liquid crystal.

AC silicon PN junction photodiode light-valve substrate

There is disclosed a single crystal silicon charge storage apparatus suitable for use in an alternating current driven liquid crystal light valve. The charge storage medium is made of a high resistivity and photosensitive under AC excitation substrate on which an MOS capacitor is formed having fast photoelectric transient response and capable of operating over a wide frequency range. The AC activation provides to a liquid crystal light valve a greatly improved electrochemical stability. Electrically coupled high-reflectivity mirrors and light blocking layers can be used to couple the liquid crystal to the MOS capacitor.

Continuous silicon MOS AC light valve substrate

There is disclosed an electro-optical system for real time projection of very high brightness, full color pictorial images from television or other program sources onto a large display screen from a set of three reflection type AC driven field effect mode birefringent liquid crystal light valves each of which modulates a primary color component video image onto a collimated beam of polarized light of a given primary color by modulating the polarization state thereof. In order to achieve very high brightness without overheating the system it is necessary that none of the optical elements forming the projection beam optical system absorb light in carrying out their function. Hence all projection beam optical processes are non-absorptive to first order. The light valves are devices that receive and reflect projection light from an independent high power light source while modulating onto the reflected light video images derived from a low level light source such as a cathode ray tube. The modulation onto the projection beam is achieved by modulating the state of polarization thereof. One such device is used for the red portion of the video image, a second for the green portion and a third for the blue portion. The optical system derives light from a white projection light source, polarizes it, splits it into the three primary colors, directs the three colored beams to the three light valves respectively for image modulation, collects the light that has been modulated by the light valves, recombines the three beams, and projects them onto the screen with sufficient registration to create full color range for the full color image. The optical system uses only a single projection lens and a single polarizing/analyzing beam splitter/recombiner and suitable dichroic mirrors. There is thus provided a simple, compact low weight, high brightness and high efficiency full color light valve image projection system for the projection of high brightness, full color, real time dynamic or static imagery which may include provision for overlay legends or other information as well as possible steroscopic or three dimensional perception by the viewer.

High brightness full color image light valve projection system

There is disclosed an anisotropically conductive interface comprising a plurality of cermet and dielectric layers for use in electro-optical devices to separate a substrate driver from an electro-optical display medium to prevent display light from affecting the driver. The substrate may be a photosensor, a charge coupled device or other matrix addressing circuitry arrangement. In general the substrate is one which can provide spatially modulated voltage and/or current patterns. The display medium may be a liquid crystal, an electro-chromic, an electro-luminescent material or the like. The interface provides direct current conductivity through the interface, insulative maintenance of the spatial modulation of the signal across the interface, light reflectivity, and high attenuation of transmitted light.

Cermet interface for electro-optical devices

There is disclosed a high performance reflective mode liquid crystal light valve suitable for general image processing and projection and particularly suited for application to real-time coherent optical data processing. A preferred example of the device uses a CdS photoconductor, a CdTe light absorbing layer, a dielectric mirror, and a liquid crystal layer sandwiched between indium-tin-oxide transparent electrodes deposited on optical quality glass flats. The non-coherent light image is directed onto the photoconductor; this reduces the impedance of the photoconductor, thereby switching the AC voltage that is impressed across the electrodes onto the liquid crystal to activate the device. The liquid crystal is operated in a hybrid field effect mode. It utilizes the twisted nematic effect to create a dark off-state (voltage off the liquid crystal) and the optical birefringence effect to create the bright on-state. The liquid crystal thus modulates the polarization of the coherent read-out or projection light responsively to the non-coherent image. An analyzer is used to create an intensity modulated output beam.

Reflective liquid crystal light valve with hybrid field effect mode

There is disclosed a high performance coherent optical data processing system using a reflective mode liquid crystal light valve which is particularly suited for application to real-time coherent optical data processing. A preferred example of the system uses a reflective light valve comprising a CdS photoconductor, a CdTe light absorbing layer, a dielectric mirror, and a liquid crystal layer sandwiched between indium-tin-oxide transparent electrodes deposited on optical quality glass flats. The non-coherent light image is directed onto the photoconductor; this reduces the impedance of the photoconductor, thereby switching the AC voltage that is impressed across the electrodes onto the liquid crystal to activate the device. The liquid crystal is operated in a hybrid field effect mode. It utilizes the twisted nematic effect to create a dark off-state (voltage off the liquid crystal) and the optical birefringence effect to create the bright on-state. The liquid crystal thus modulates the polarization of the coherent read-out or projection light responsively to the non-coherent image. An analyzer is used to create an intensity modulated output beam which is projected through a Fourier transform lens onto a screen or other detector means.

Growing community of inventors

Topanga, CA, United States of America

Alexander D Jacobson