Mechanical dither control optimization for laser gyro with total reflection prisms

For the phenomenon of the lock-in area and quality factor for dither mechanism vary with the temperature in laser gyro with total reflection prisms (TRP-LG), as well as the traditional mechanical dither control method with controlling the stability of offset and fixing the depth of noise cannot guarantee high measurement precision. TRP-LG's lock-in error characteristics are studied systematically. The effects of mechanical dither parameters on TRP-LG's zero bias stability and angle random walk are discussed in detail, and the debugging range is given. In the end, a new dither control method is proposed. The new mechanical dither control method controls the stability of the magnitude of the dither and adjusts the depth of noise in dither signal according to different temperature ranges, and the algorithm of the depth of noise is given. Experimental results show that the zero bias stability and angle random walk of the TRPLG are improved by over 40% in the full temperature range. The analytic result provides an important reference for improving the performance of other mechanical dither laser gyros.