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:
Oct. 26, 1999
Filed:
Aug. 19, 1998
Applicant:
Inventors:
Assignee:
Hitachi, Ltd., Tokyo, JP;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
G02F / ;
U.S. Cl.
CPC ...
349-5 ; 349-8 ; 349132 ; 349 99 ; 349121 ;
Abstract
A liquid crystal projector having a high contrast ratio has an optical system including, for each color, a liquid crystal display device, a drive device for driving the liquid crystal display device and a polarization device, and a light source. The liquid crystal display device has active devices connected to reflective electrodes. Driving voltages applied to pixels have different polarities in every row. The liquid crystal layer is aligned at an angle from 75.degree. to 105.degree. to the direction of an electric field between electrodes. An optical rotator is provided between the liquid crystal display device and the polarization device.