Sources of error and noise in a magnetic mirror gyro

A ring laser gyroscope biased by a magneto-optic mirror offers a promising alternative to mechanical dither, for applications requiring no dither and able to tolerate lower performance. The effect of the important mirror parameters: optical loss, scatter and transverse Kerr effect, on gyro performance, is defined. Explicit expressions, obtained from the literature and supplemented by new calculations, are given for the expected null-shift, random walk, and scale-factor nonlinearity; numerical values are listed for a typical magnetic mirror, indicating where improvements are required for potential applications.