Abstract: A mechanical scanning system for the illuminating laser beam and return light in LIDAR imaging systems. The scanning system includes a flat mirror having reciprocating rotary motion around a horizontal axis for vertical scan of the illuminating laser beam and return light. The reciprocating rotary motion of the mirror is driven by a continuously rotating motor, a cam mounted on the motor and a follower connected to the mirror and driven by the cam. An encoder is connected to the mirror's shaft and provides position indication to the imaging control electronics.