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. 22, 2003
Filed:
Sep. 13, 2001
Hiroaki Naganuma, Kofu, JP;
Nisca Corporation, Yamanashi-ken, JP;
Abstract
A light amount control apparatus includes at least one blade member facing an optical axis aperture on a base plate and freely opening and closing the aperture, a rotating magnet rotor interconnected with the blade member to open and close the blade members, a coil and/or soft magnetic member to apply rotational torque to the magnet rotor, and a regulating device to regulate the movement of the magnet rotor within a prescribed angle. The regulating device is located to provide the magnetic rotor with an opening region and a closing region different from each other with respect to a neutral point so that a rotational torque acting on the magnet rotor differs by the regulating device to regulate the rotational movement of the at least one blade member in the opening and closing regions.