The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.

The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.

Date of Patent:
Jan. 16, 1990

Filed:

Dec. 23, 1987
Applicant:
Inventor:

Murray S Welkowsky, Chatsworth, CA (US);

Assignee:

Hughes Aircraft Company, Los Angeles, CA (US);

Attorneys:
Primary Examiner:
Int. Cl.
CPC ...
H04N / ;
U.S. Cl.
CPC ...
358231 ; 358232 ; 358 61 ;
Abstract

A video projector system is used to produce a substantially flicker-free optical video image, which is then applied to a liquid crystal light valve (LCLV) to modulate and impose the video image upon a readout infrared (IR) or ultra-violet (UV) beam. The optical projector preferably employs a high impedance electro-optical crystal which receives a video pattern of electric charges from an electron beam operating in conjunction with a conductive grid adjacent the crystal, the grid receiving a video signal in synchronism with the scanning electron beam. The LCLV is preferably of the type which includes a liquid crystal layer integrated within a metal-oxide-semiconductor structure. The undesirable effects of any asymmetry between the WRITE and ERASE response times of the video projector are reduced by making the WRITE response faster than the ERASE response, and having the LCLV operational voltage threshold above the voltage level attained at the end of an ERASE period. An incomplete video projector ERASE thus results in a complete LCLV ERASE.


Find Patent Forward Citations

Loading…