A gyroscope system comprises a gyroscope block having a plurality of cavities and a plurality of passages that define a path; a plurality of mirrors each located in one of the plurality of cavities; at least one mirror drive coupled to one of the plurality of mirrors and configured to change a position of the respective mirror, wherein the path's length is changed by the change in the position of the respective mirror; a dither system coupled to the gyroscope block and configured to induce an angular rotation of the gyroscope block; and a controller configured to provide a dither signal indicative of a dither frequency to the dither system and a path length control (PLC) signal indicative of a PLC frequency to the at least one mirror drive. The controller is configured to calculate the PLC frequency as a function of the dither frequency.