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. 10, 2009
Filed:
Oct. 27, 2006
Wei Gao, Sendai, JP;
Satoshi Kiyono, Sendai, JP;
Yoshiyuki Tomita, Hiratsuka, JP;
Toru Hirata, Yokohama, JP;
Yoji Watanabe, Sendai, JP;
Kennichi Makino, Hiratsuka, JP;
Wei Gao, Sendai, JP;
Satoshi Kiyono, Sendai, JP;
Yoshiyuki Tomita, Hiratsuka, JP;
Toru Hirata, Yokohama, JP;
Yoji Watanabe, Sendai, JP;
Kennichi Makino, Hiratsuka, JP;
Sumitomo Heavy Industries, Ltd., Tokyo, JP;
Tohoku Technoarch Co., Ltd., Sendai-shi, JP;
Abstract
According to one aspect of the invention, there is provided a sensor device which is capable of detecting a state of a movable stage using an easily manufacturable reference grating and capable of improving the accuracy of detection. The sensor device comprises a reference grating which has a configuration that is varied periodically in a two-dimensional direction. A light source emits light to the reference grating. A spectral unit has a plurality of openings to convert the light emitted by the light source into a plurality of light beams through the plurality of openings. A detector unit has a photodetector to receive collectively reflected light beams reflected by the reference grating. The detector unit is provided to detect a state of a movable body relative to the reference grating based on a change of the reflected light beams received by the photodetector.