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:
Sep. 13, 1988

Filed:

Mar. 12, 1987
Applicant:
Inventors:

Osamu Umeda, Gifu, JP;

Masahiro Ogawa, Tokyo, JP;

Tatsuo Shimazaki, Tokyo, JP;

Assignee:
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
G03B / ;
U.S. Cl.
CPC ...
353122 ; 353 38 ; 353102 ; 353 84 ; 353 95 ;
Abstract

In a liquid crystal projector wherein a light source is arranged behind a transmission liquid crystal display panel having a rectangular display portion, an image displayed on the liquid crystal display panel is enlarged by a projection lens, and an enlarged image is projected on the screen located in front of the liquid crystal display panel, a linear Fresnel lens is arranged between the light source and the liquid crystal display panel to narrow illumination light beam from the light source along only the widthwise direction of the rectangular display portion. When the illumination light beam from the light source is narrowed along only the widthwise direction of panel, the amount of unused light beam emitted outside the long sides of the display portion can be reduced, and the light beam from the light source can be effectively utilized for image projection.


Find Patent Forward Citations

Umeda, Osamu. (1988). Liquid crystal projector (U.S. Patent No. 4770525). U.S. Patent and Trademark Office. https://idiyas.com/patent/badge/4770525

Data source: USPTO (United States Patent and Trademark Office) public patent records. Weekly synchronization. How IDiyas builds this profile

Loading…