Method of providing phase biasing in a continuous single-mode fiber ring

Abstract

A fiber interferometer gyro employing a continuous, integral looped single-mode fiber is coupled to bidirectionally transmit clockwise and counterclockwise pulsed beams of light through a coiled continuous integral single-mode fiber from a laser to a pair of detectors. A suitably polarized piezoelectric cylinder is fitted about a portion of the continuous integral single-mode fiber to change the refractive index of that portion of the continuous integral single-mode fiber when appropriate electric fields are impressed across it. Changing the refractive index in only that portion of the continuous integral single-mode fiber results a selective phase biasing between the clockwise and counterclockwise traveling pulsed beams so that a rotation displacement of the interferometer gyro is more easily detected. This enhanced capability does not compromise the interferometer's effectiveness since its integral, continuous path is not broken nor are other elements introduced in the light pathway provided by the continuous single-mode fiber.