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:
Jul. 08, 1997
Filed:
Oct. 26, 1994
Applicant:
Inventor:
Koichi Ohshita, Tokyo, JP;
Assignee:
Nikon Corporation, Tokyo, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
G02B / ; G03B / ;
U.S. Cl.
CPC ...
359422 ; 359432 ; 359689 ; 396378 ; 396379 ;
Abstract
A Keplerian zoom finder optical system has an objective lens comprising, in succession from the object side, a first lens unit of negative refractive power, a second lens unit of positive refractive power, and a third lens unit of positive refractive power and having positive refractive power as a whole, and an eyepiece of positive refractive power for enlarging and observing the focused image of the objective lens therethrough. The air gap between the first lens unit and the second lens unit is varied to thereby vary finder magnification.