零闭锁激光陀螺(ZLG)增益曲线不对称导致左、右旋陀螺的比例因子修正系数不相等，使得当陀螺稳频工作点与磁不敏感点存在频率差时，陀螺零偏对外界磁场变化敏感，降低了陀螺的精度并限制了使用环境。利用兰姆半经典理论分析计算了比例因子修正系数与增损比的关系，并得到了陀螺的磁不敏感点与放电电流的关系，从信号处理系统中排除放电电流变化对控制信号的影响，并进行了实验验证。理论计算和实验结果均表明，线性地改变陀螺放电电流，陀螺磁不敏感点位置会因增益曲线的增损比变化而发生相应线性改变，进而能够通过控制放电电流降低陀螺的磁灵敏度。

Since the asymmetry of laser gain leads to the unequal of scale factor corrections between left circularly polarized and right circularly polarized gyros in the cavity, zero-lock laser gyro (ZLG) bias is sensitive to magnetic field when frequency stabilization point is not matched with magnetic insensitive point, which degrades the precision and limits work condition of ZLG. The relation between scale factor corrections and gain-to-loss ratio is analyzed according to Lamb semiclassical theory, as well as the relation between magnetic insensitive point and discharge current. The influence of discharge current changing on control signal is eliminated from signal processing system and experimental verification is performed. It is proved by both theoretical calculation and experimental results that the magnetic insensitive point varies linearly with gain-to-loss ratio as the discharge current changes linearly, which means that the magnetic sensitivity can be reduced by changing discharge current.