OPTICAL FIBER RATE SENSOR

摘要

PURPOSE:To reduce noise output by suppressing drift, by supplying polarized light to a constant polarization fiber from a polarized light source having a wide spectrum band and guiding non-polarized light of the output from said fiber to an optical fiber loop and a light detector. CONSTITUTION:The light from a light source 11 emitting high intensity light having a wide spectrum band contains polarized light and said light source 11 is coupled to a contant polarization fiber 12 so that the polarization surface of said light source 11 forms an angle of 45 deg. to the polarization conservation surface of said fiber 12. An optical directional coupler 14 separates the light from the constant polarization fiber 12 into constant polarization fibers 17, 18. The light of the fiber 18 is supplied to an optical directional coupler 20 where separated into constant polarization fibers 21, 22 and the separated lights are respectively transmitted through the constant polarization fiber 24 wound around a drum 23 in directions oppisite to each other. Transmitted light from the fiber 21 is supplied to a light detector 30 and a lock-in amplifier 31 through a constant polarization fiber 29 and interference light thereof is detected.