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. 07, 2017
Filed:
Jan. 27, 2016
Dmg Mori Seiki Co., Ltd., Yamato-Koriyama, Nara, JP;
Akinori Suzuki, Isehara, JP;
Masayuki Niiya, Isehara, JP;
Kenji Matsushita, Isehara, JP;
Terukazu Nishida, Isehara, JP;
Hideaki Tamiya, Isehara, JP;
Kayoko Taniguchi, Isehara, JP;
DMG MORI SEIKI CO., LTD., Yamato-Koriyama, JP;
Abstract
A displacement detection apparatus capable of stably and accurately detecting the amount of displacement. The length of a polarization maintaining fiber for transmitting the light from a light source to a displacement detector is set not to be equal to a length obtained by dividing, by the wavelength of the light source, a product of an even integral multiple of a length, which is obtained by multiplying twice the length of a resonator by the refractive index of the resonator, and a beat length obtained by a difference between the propagation constants of two polarization modes. Alternatively, the length of the polarization maintaining fiber is set to be larger than a length, which is obtained by dividing, by the wavelength of the light source, a product of a coherence length and a beat length obtained from a difference between the propagation constants of two polarization modes.