METHOD AND APPARATUS FOR MIRROR CONTROL

It is sometimes required to track randomly moving objects with precision and high speed. This inventioin pertains to a mirro rotation assembly that provides precise, high-speed pitch and yaw tracking by rotating a low-moment-of-inertia mirror rather than rotating a heavier double gimballed mirror assembly or the camera-lens assembly itself. By pivoting the mirror on a single bearing point and controlling the mirror surface pitch and yaw by driving two mirror tie points along circumferential paths around the bearing point, a low moment of inertia is obtained. The low moment of inertia together with mirror velocity rather than position control permits higher speed tracking while maintaining the required precision. The velocity control strategy minimizes image blur resulting from unpredicted object motions.