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:
Oct. 08, 2013
Filed:
Oct. 24, 2011
Sadayuki Matsumiya, Sagamihara, JP;
Tatsuya Nagahama, Kawasaki, JP;
Atsushi Usami, Kawasaki, JP;
Mitutoyo Corporation, Kawasaki, JP;
Abstract
Disclosed is an interference objective lens unit, comprising: an objective lens; a beam splitter that splits the light transmitted through the objective lens into a reference optical path in which a reference mirror is provided and a measuring optical path in which the measuring object is placed, and that superposes the split lights to output interference light; a first holder that holds the objective lens and that is formed by material having a first linear expansion coefficient; and a second holder that holds the reference mirror and that is formed by material having a second linear expansion coefficient different from the first linear expansion coefficient, wherein when a usage environment temperature changes, a difference in the linear expansion coefficients between the first holder and the second holder corrects an optical path difference between the reference optical path and the measuring optical path.