为了实现对大视场范围的目标进行搜索捕获或者成像，采用了二维指向镜与面阵探测器相结合的技术方案。对二维指向镜系统电机转角耦合特性和成像规律进行研究。首先，从光学反射矢量理论出发对二维指向镜系统建立数学模型，解耦得到扫描电机转角与视轴指向方位角之间的关系；然后，从数学模型出发可得出电机扫描时目标在像面的扫描轨迹和二维扫描镜系统造成的像旋情况，实验测得扫描轨迹的倾角与计算所得的轨迹倾角误差小于0.1°，像元位置偏差不到0.2个像元；最后，分析了采用二维扫描镜的成像系统消除像旋的算法，为二维指向镜实现精确跟踪和软件校正像旋提供理论依据。

Twoaxis gimbaled mirror systems are commonly used in optical searching or imaging systems.But due to the coupling of the two orthogonal axes,the scan trace on the sensor may be curvilinear,and the image may rotate relative to the object plane.In this paper,a model of the twoaxis gimbaled mirror system was built up,and the relationship of the motor angle with the objects azimuth and elevation angle was analyzed.Thus the scan trace of the image on the senor,and the image rotation of the system were obtained.Finally,a method was given to correct the image rotation.Experimental results indicated that obliquity error between the measurement in experiment and the analysis result was less than 0.1°,which made the position error on detector less than 0.2 pixels.