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:
Apr. 03, 2012
Filed:
Jun. 28, 2006
Yasuhiro Hidaka, Kumagaya, JP;
Tadashi Nagayama, Tokyo, JP;
Yasuhiro Hidaka, Kumagaya, JP;
Tadashi Nagayama, Tokyo, JP;
Nikon Corporation, Tokyo, JP;
Abstract
A surface position detection apparatus capable of highly precisely detecting the surface position of a surface to be detected without substantially being affected by relative positional displacement due to a polarization component occurring in a light flux having passed through a reflective surface. In the apparatus, a projection system has a projection side prism member () having first reflective surfaces (), and a light receiving system has a light receiving prism member () having second reflective surfaces () arranged in correspondence with the projection side prism member. The surface position detection apparatus further has a member for compensating relative positional displacement due to a polarization component of a light flux having passed through the first and second reflective surfaces.