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:
Mar. 25, 1986

Filed:

Feb. 08, 1982
Applicant:
Inventors:

Kazuo Yamakawa, Sakai, JP;

Toshihide Dohi, Minamikawachi, JP;

Assignee:
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
G02B / ; G02B / ;
U.S. Cl.
CPC ...
350432 ; 350412 ;
Abstract

Disclosed is a lens system for projecting onto a screen a video image formed on a face plate of a cathode ray tube and including, a first positive lens unit, a second positive lens unit defined between a pair of convex surfaces and a third negative lens unit having a screen side concave surface. The lens system includes at least one aspheric surface and fulfills the following condition: 1.5f<fl<2.0f, wherein f represents the focal length of the whole lens system and fl represents the focal length of the first positive lens unit.


Find Patent Forward Citations

Yamakawa, Kazuo. (1986). Video projector lens system (U.S. Patent No. 4577935). U.S. Patent and Trademark Office. https://idiyas.com/patent/badge/4577935

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

Loading…