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:
Jan. 21, 2003
Filed:
May. 09, 2001
Fuyuhiko Inoue, Sagamihara, JP;
David Stumbo, Belmont, CA (US);
Nikon Corporation, Tokyo, JP;
Abstract
An interferometric measuring system including a movable member having a measurement reflector attached thereto, a stationary member having a reference reflector attached thereto, a light source for providing a light beam, and an optical support block having first and second beam splitters mounted thereon. The first beam splitter is operable to convert the light beam into a first pair of orthogonally polarized beams and arranged to direct one of the first pair of beams along a reference path to the reference reflector and the other of the first pair of beams along a measurement path to the measurement reflector to create a measurement interference pattern between the first pair of beams for determining a position of the movable member. The second beam splitter is operable to form a second pair of orthogonally polarized beams and arranged to direct the second pair of beams along support block measurement paths to the reference reflector. The second beam splitter is configured to form a correction interference pattern between the second pair of beams for determining error in the position of the movable member due to movement of the optical support block.