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. 11, 1992
Filed:
Jun. 24, 1991
Applicant:
Inventors:
Akihiko Nagano, Kawasaki, JP;
Kazuki Konishi, Hino, JP;
Hiromi Someya, Kawasaki, JP;
Tokuichi Tsunekawa, Yokohama, JP;
Assignee:
Canon Kabushiki Kaisha, Tokyo, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
G03B / ; G02B / ;
U.S. Cl.
CPC ...
354406 ; 25020118 ;
Abstract
In an apparatus for detecting the relative positional relation between light intensity distributions relating to an object image and detecting the focus-adjusted state of an objective lens, a pair of stop openings for limiting an off-axis light flux forming light intensity distributions entering a pair of secondary imaging lenses are provided so as to be symmetrical with respect to a meridian centered at the optic axis of the objective lens so that the influence of the residual aberrations of the objective lens becomes uniform.