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:
May. 08, 2001
Filed:
Oct. 24, 1996
Koh Ishizuka, Omiya, JP;
Canon Kabushiki Kaisha, Tokyo, JP;
Abstract
A displacement information detection apparatus includes a light generation unit, a first unit including a first grating for displacement information detection and one or more lens members for original detection, and a second unit including a second grating for displacement detection, which cooperates with the first grating, and an origin detection mark. The apparatus also includes at least one first light-receiving element for receiving light generated by the light generation unit and propagated via the first and second gratings, and outputting a signal including relative displacement information between the first and second units. The apparatus also includes one or more second light-receiving elements for receiving light generated by the light generation unit and propagated via the lens member. The second light-receiving elements output a signal indicating an origin based on a change in light-receiving state when the origin detection mark is present in the optical path of light leaving the lens member.