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:
Dec. 03, 1985
Filed:
Sep. 30, 1982
Applicant:
Inventor:
Takahiro Sugiyama, Tokyo, JP;
Assignee:
Asahi Kogaku Kogyo Kabushiki Kaisha, Tokyo, JP;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
G02B / ;
U.S. Cl.
CPC ...
350475 ;
Abstract
An objective lens for use with an information storage disk comprises a three-group three-element lens system including a first group composed of a positive-meniscus lens having a convex side directed toward a light source, a second group composed of a negative-meniscus lens having a concave side directed toward the light source, and a third group composed of a positive-meniscus lens having a convex side directed toward the light source. The objective lens satisfies the following requirements: