Alexander S Jacobson

US Patent:

40185095, Apr 19, 1977

Filed:

Mar 8, 1976

Appl. No.:

5/664777

Inventors:

Donald D. Boswell - Granada Hills CA
Jan Grinberg - Los Angeles CA
Alexander D. Jacobson - Topanga CA
Gary D. Myer - Reseda CA

Assignee:

Hughes Aircraft Company - Culver City CA

International Classification:

G02F 113

US Classification:

350160LC

Abstract:

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.

US Patent:

42393485, Dec 16, 1980

Filed:

Nov 30, 1979

Appl. No.:

6/099381

Inventors:

Jan Grinberg - Los Angeles CA
Michael Waldner - Woodland Hills CA
Paul Q. Braatz - Los Angeles CA
Alexander D. Jacobson - Topanga CA

Assignee:

Hughes Aircraft Company - Culver City CA

International Classification:

G02F 1135

US Classification:

350342

Abstract:

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.

US Patent:

40933571, Jun 6, 1978

Filed:

Apr 5, 1977

Appl. No.:

5/784894

Inventors:

Alexander D. Jacobson - Topanga CA
Jan Grinberg - Los Angeles CA
Paul O. Braatz - Los Angeles CA
William P. Bleha - Carlsbad CA

Assignee:

Hughes Aircraft Company - Culver City CA

International Classification:

G02F 113

US Classification:

350338

Abstract:

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.

US Patent:

41986474, Apr 15, 1980

Filed:

Jan 17, 1979

Appl. No.:

6/004107

Inventors:

Jan Grinberg - Los Angeles CA
Alexander D. Jacobson - Topanga CA
William P. Bleha - Carlsbad CA
Paul O. Braatz - Los Angeles CA

Assignee:

Hughes Aircraft Company - Culver City CA

International Classification:

H01L 2714

US Classification:

357 30

Abstract:

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.

US Patent:

41273222, Nov 28, 1978

Filed:

Dec 5, 1975

Appl. No.:

5/637906

Inventors:

Alexander D. Jacobson - Topanga CA
Jan Grinberg - Los Angeles CA
Donald E. Sprotbery - Huntington Beach CA
Donald D. Boswell - Granada Hills CA

Assignee:

Hughes Aircraft Company - Culver City CA

International Classification:

H01J 2989
G03B 2100
G02F 101

US Classification:

353 31

Abstract:

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.

US Patent:

41914546, Mar 4, 1980

Filed:

Oct 10, 1978

Appl. No.:

5/949840

Inventors:

Paul O. Braatz - Los Angeles CA
Jan Grinberg - Los Angeles CA
Alexander D. Jacobson - Topanga CA
Michael Waldner - Woodland Hills CA

Assignee:

Hughes Aircraft Company - Culver City CA

International Classification:

G02F 113

US Classification:

350342

Abstract:

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.

US Patent:

41914520, Mar 4, 1980

Filed:

Dec 28, 1977

Appl. No.:

5/865281

Inventors:

Jan Grinberg - Los Angeles CA
Paul O. Braatz - Los Angeles CA
Michael Waldner - Woodland Hills CA
Alexander D. Jacobson - Los Angeles CA

Assignee:

Hughes Aircraft Company - Culver City CA

International Classification:

G02P 113

US Classification:

350342

Abstract:

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.

US Patent:

44430647, Apr 17, 1984

Filed:

Dec 10, 1980

Appl. No.:

6/214930

Inventors:

Jan Grinberg - Los Angeles CA
Michael Waldner - Woodland Hills CA
Paul O. Braatz - Los Angeles CA
Alexander D. Jacobson - Topanga CA

Assignee:

Hughes Aircraft Company - El Segundo CA

International Classification:

G02F 113

US Classification:

350334

Abstract:

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.