Honeywell’s GG1320 digital ring laser gyros (RLG) is the industry standard for precision rotation measurement.
RLG's are critical rotation sensing elements in navigation systems for manned and unmanned aircraft, platform stabilization systems, pointing and targeting, marine navigation and attitude and heading reference systems (AHRS). The principle of operation of an RLG is that counter-propagating laser beams have different frequencies with the difference dependent on rotation rate. Measurement of this difference provides the rotation angle or rotation rate about the RLG's sensitive axis. One can thus determine the orientation of a system in inertial space at all times.