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:
Mar. 24, 1995
Applicant:
Inventors:
Osamu Sato, Saitama-ken, JP;
Koichi Shimada, Saitama-ken, JP;
Assignee:
Canon Denshi Kabushiki Kaisha, Saitama-ken, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
G02B / ;
U.S. Cl.
CPC ...
359230 ; 359227 ; 396505 ; 396508 ; 396510 ;
Abstract
A light-quantity control device includes a drive source, a light-quantity control member which is arranged to vary the amount of opening of an aperture by shifting its position, and a speed control part which is arranged to control the driving speed of the drive source in proportion to a rate of change per unit time of the area of the aperture of the light-quantity control member.