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:
Jun. 14, 2011
Filed:
Aug. 24, 2009
Isamu Hirai, Tokyo, JP;
Isamu Hirai, Tokyo, JP;
Hoya Corporation, Tokyo, JP;
Abstract
An image surface illuminance varying apparatus includes a variable power optical system in which the optical power thereof can be varied by changing a relative position of a plurality of optical elements thereof; and a light-quantity ratio varying optical element whose transmittance varies in a direction perpendicular to an optical axis of the variable power optical system, the light-quantity ratio varying optical element being located in a light path of the variable power optical system to reduce an illuminance difference of an imaging surface. A distance from the light-quantity ratio varying optical element, which is moved along the optical axis, to a diaphragm or a shutter is varied in accordance with the power varying operation.
Data source: USPTO (United States Patent and Trademark Office) public patent records. Weekly synchronization. How IDiyas builds this profile