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:
Mar. 16, 1982
Filed:
Dec. 18, 1979
Applicant:
Inventor:
Ikuo Mori, Kawasaki, JP;
Assignee:
Nippon Kogaku K.K., Tokyo, JP;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
G02B / ;
U.S. Cl.
CPC ...
350469 ;
Abstract
A four-group lens comprises, in succession from the object side, a first group, a second group, a diaphragm, a third group and a fourth group. These four groups are formed substantially symmetrically with respect to the diaphragm. The air space between the first and second groups and the air space between the third and fourth groups are variable in accordance with a change of the photographing magnification.