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:
Feb. 26, 1991
Filed:
Oct. 30, 1987
Applicant:
Inventor:
Shuji Aruga, Nagano, JP;
Assignee:
Seiko Epson Corporation, Tokyo, JP;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
G02F / ;
U.S. Cl.
CPC ...
3503 / ; 3503 / ; 350334 ; 3503 / ; 350379 ; 350174 ;
Abstract
A projection-type display device using twisted nematic liquid crystal light valves in which the photoelectric transfer characteristics of three light valves for selectively transmitting red, green and blue light to a synthesizing device are matched. The product of the birefrigence .DELTA.n and thickness d of the twisted nematic liquid crystal and thickness of cell is selected to fall within a predetermined optimal range of values depending upon the wavelength of light which travels therethrough. The thickness d or birefrigence .DELTA.n of the twisted nematic liquid crystal material of each light valve may be the same.