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:
Jan. 26, 2010
Filed:
Dec. 14, 2006
Yasunori Saito, Honjo, JP;
Hitoshi Nozue, Chichibu, JP;
Yasunori Saito, Honjo, JP;
Hitoshi Nozue, Chichibu, JP;
Canon Denshi Kabushiki Kaisha, Saitama-ken, JP;
Abstract
This invention prevents a degradation in image quality resulting from undesirable reflected light and undesirable transmitted light generated near the ridgeline of the edge portion of an optical element including an aperture blade or an ND filter. The aperture edge of the aperture blade cooperates with the aperture edge of another aperture blade to form an almost rhombic aperture. A small saw-toothed and non-periodic uneven portions having various sizes are formed along two, front and rear ridgelines of the aperture edge and along those of the ND filter. When incident light beams strike the aperture edge of the aperture blade or the edge of ND filter, the uneven portions formed at the ridgeline reflect them in various directions.