Two source passive ring laser gyroscope

TLDR: In this article, a two-source passive ring resonator gyroscope with integral first, second and third resonator cavities is used to provide a first single frequency light source.

Abstract: A two source passive ring resonator gyroscope having a single piece body with integral first, second and third resonator cavities. A first laser means uses the first resonator cavity to provide a first single frequency light source. A second laser uses the second resonator for a second laser to provide a second single frequency light source. The third resonator cavity is a passive high Q evacuated cavity having a closed optical path tuned to resonate at substantially the light frequency of the first and second resonator cavities. The first signal frequency light source is split into a propagating light source and a first reference frequency light source. The propagating source is coupled into the third resonator cavity to form a propagating light beam. The second single frequency light source is split into a second frequency light source and into a second reference frequency light source. The light from the second frequency light source is modulated at the reference carrier frequency (FO) to form a carrier modulated offset frequency counterpropagating light source. This source is coupled into the third resonator cavity. Two cavity servos respond to the first and second dither signals to provide control signals to the first and second laser transducers to control the resonant frequency of the first and second single frequency light sources.