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.
Patent No.:
Date of Patent:
Mar. 05, 1991
Filed:
Jun. 12, 1989
Applicant:
Inventors:
Richard L Cohen, Matawan, NJ (US);
Rubin Gelles, New York, NY (US);
Assignee:
Allied-Signal Inc., Morris Township, Morris County, NJ (US);
Attorneys:
Primary Examiner:
Int. Cl.
CPC ...
G02F / ;
U.S. Cl.
CPC ...
350345 ; 350338 ;
Abstract
A liquid crystal display system utilizes an optical arrangement which is aligned so that ambient light from the direction of an obersver's view is channeled behind the liquid crystal display to provide back illumination therefor. An illuminator is arranged to provide supplementary illumination for the liquid crystal display as may be required. A photodetector determines when ambient light is inadequate for required display brightness and operates through appropriate control circuitry to turn the illuminator on or off as the case may be and to control the contrast of the liquid crystal display.