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. 29, 1999
Filed:
Feb. 06, 1996
Kou Ishizuka, Ohmiya, JP;
Canon Kabushiki Kaisha, Tokyo, JP;
Abstract
In an apparatus for detecting information on the rotation of an object using a grating interference system, the present invention provides a rotation detecting apparatus, which can be sufficiently miniaturized even when using another rotation information detecting section at the same time, and an apparatus for controlling the rotation using the same. The apparatus has a first detecting device for detecting by making the diffracted light from the diffraction grating interfere to detect rotation information of the object, a second detecting device for detecting the light from the predetermined data recording section to detect rotation information of the object, and a light beam illuminating device common to the first and second detecting means for illuminating the diffraction grating and the predetermined data recording section together.