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, 2008
Filed:
Jun. 23, 2005
Hiroaki Naganuma, Kofu, JP;
Hiroaki Naganuma, Kofu, JP;
Nisca Corporation, Minamikoma-Gun, Yamanashi-Ken, JP;
Abstract
A light quantity adjusting device includes a ring-shaped base plate having an exposure aperture at a center thereof, a first light quantity adjusting blade arranged in the exposure aperture, a first drive device for opening/closing the first light quantity adjusting blade, a second light quantity adjusting blade arranged in the exposure aperture, and a second drive device for opening/closing the second light quantity adjusting blade. The first drive device includes a magnet rotor and an exciting coil formed in a ring shape, and a guiding member for inducing a magnetic field to a position facing a magnetic pole formed on a circumference side of the magnet rotor. The second drive device includes a magnet rotor, an exciting coil, and a guiding member for guiding a magnetic field to a position facing a magnetic pole formed on a circumference side of the magnet rotor.