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:
Aug. 30, 1988
Filed:
Jun. 06, 1985
Applicant:
Inventors:
Assignee:
Konishiroku Photo Industry Co., Ltd., Tokyo, JP;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
G02B / ; G02B / ;
U.S. Cl.
CPC ...
350432 ; 350465 ;
Abstract
For small type wide angle lenses for use with a compact camera, so-called inverted retrofocus lenses are often used. In this type of lens, the lens can be formed into more compact by increasing a refracting power of a rear unit of a negative meniscus with a convex surface thereof greatly curved toward an image and a front unit on the side of an object. However, this arrangement gives rise to an aberration. This aberration can be compensated by introducing at least one aspherical surface into the front unit and rear unit. In addition, this aspherical lens can be easily produced if it is formed of plastics.