US Patent 7944565 Semiconductor ring laser gyro

A semiconductor ring laser gyro includes: a semiconductor laser for emitting light from each end of the gyro; at least one reflection prism comprising a plurality of reflection surfaces for forming an optical circuit, the at least one reflection prism adapted to receive and internally reflect the light emitted from the semiconductor laser; a transmissive mirror disposed at one of the plurality of reflection surfaces of the at least one reflection prism and adapted to transmit part of the light traveling clockwise and part of the light traveling counterclockwise through the optical circuit; and a beam multiplexing prism for multiplexing the light transmitted through the transmissive mirror.