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:
May. 13, 1997
Filed:
Aug. 10, 1995
Shoji Sakata, Tsukuba, JP;
Abstract
A laser strainmeter has a plurality of sensor resonators, each comprising a multiple reflection interferometer having a pair of concave mirrors (8) which are secured to the inner wall of a container (1) to face each other in the diametrical direction of the container so that the optical axes of the sensor resonators extend in different directions. The laser strainmeter further has a reference resonator comprising a multiple reflection interferometer having a pair of concave mirrors (12) which are disposed in the vicinity of the sensor resonators, and which are held at a fixed distance. Laser light having the same resonance frequencies as those of the associated resonators are transmitted from laser oscillators to the resonators through optical fibers (3). A change in distance between the pair of concave mirrors of each of the sensor resonators is obtained from a difference in resonance frequency between each sensor resonator and the reference resonator, thereby obtaining a strain change of a medium in which the container is buried.