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:
Mar. 14, 2017
Filed:
Feb. 12, 2015
Canon Kabushiki Kaisha, Tokyo, JP;
Canon Kabushiki Kaisha, Tokyo, JP;
Abstract
This disclosure provides a detection apparatus configured to detect a moire pattern generated by grid patterns having grid pitches different from each other including: an image-pickup unit configured to pick up an image of the moire pattern; an imaging optical system configured to cause the image-pickup unit to image the moire pattern; and a processing unit configured to process an image-pickup result of the moire pattern imaged by the image-pickup unit, wherein a mark including a plurality of patterns having a width not larger than the resolving power of the imaging optical system arranged in a measuring direction and changed in duty ratio between the widths and intervals of the plurality of patterns is imaged by the image-pickup unit, and the processing unit evaluates the detection apparatus by processing the image-pickup result of the mark picked up by the image-pickup unit.