Patent ID: 7836773
Filing Date: 2010-11-23
Classification: G01D,G01K,G01L

Abstract:
1. An optical fiber thermometer comprising: one optical fiber for projection that relays light from a light source to a measuring unit, two optical fibers for light-reception that relay light reflected from a reflecting face of a mirror provided at the measuring unit to two light-receiving units, and an arithmetic processing circuit that calculates the temperature of the measuring unit from the ratio of electrical signals from the two light-receiving units, wherein end surfaces of three optical fibers arranged to face the reflecting face being fixed such that an angle θ between the longitudinal direction of the optical fibers and the normal to the reflecting face is not zero, the two optical fibers for light-reception being parallel, fixing angles between each of them and the optical fiber for projection being symmetrical based on the normal to the reflecting face as a reference, and each of the optical fibers being a single-mode fiber at the wavelength being used.