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:
Apr. 18, 2000
Filed:
Apr. 16, 1997
Applicant:
Inventors:
Assignee:
Minolta Co., Ltd., Osaka, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
G02B / ; G02B / ; G02B / ;
U.S. Cl.
CPC ...
359643 ; 359656 ; 359646 ; 359660 ; 359795 ; 359558 ; 396373 ;
Abstract
A viewfinder optical system has a relay lens system. The relay lens system focuses a primary image to form a secondary image. The relay lens is provided at an optical conjugate point with respect to a pupil. A surface of the relay lens system has an optical power of diffraction. The surface is positioned between the primary image and the optical conjugate point. The surface also has optical power of refraction.