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:
Sep. 13, 1988
Filed:
Nov. 15, 1982
Applicant:
Inventor:
Youichi Okuno, Kanagawa, JP;
Assignee:
Canon Kabushiki Kaisha, Tokyo, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
G03B / ;
U.S. Cl.
CPC ...
354200 ;
Abstract
A focusing screen provided with a plurality of cylindrical lenses adjacent to one another is disclosed. The adjacent two of the cylindrical lenses have individual characteristics to shift between respective areas an image of an object in opposite directions when the object is out of focus. For this reason, when in an out-of-focus condition, the amount of the slided image along a boundary line between the areas is doubled, thus permitting the operator to perform a focusing operation with high accuracy.