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:
Nov. 03, 2015
Filed:
Jul. 29, 2011
Akihiro Kuroda, Isehara, JP;
Akihiro Kuroda, Isehara, JP;
DMG MORI SEIKI CO., LTD., Yamatokoriyama, JP;
Abstract
A displacement detecting device includes an irradiation optical system, an interference optical system, a light-receiving section, and a displacement detecting section. The irradiation optical system causes two light-beams to be incident on a diffraction grating respectively at different angles with respect to a plane perpendicular to the X-direction along which grating structures of the diffraction grating are periodically arranged. The interference optical system causes two Mth-order diffracted lights of respective light-beams incident on the diffraction grating to interfere with each other, so as to generate an interference light. The light-receiving section receives the interference light and detects an interference signal. The displacement detecting section detects a vertical displacement of a surface having the diffraction grating arranged thereon based on the change of the interference signal.