OPTICAL RADAR DEVICE FOR VEHICLE

PROBLEM TO BE SOLVED: To improve the operating efficiency of a device by providing a structure for transmitting and refracting an emitted light while rotating a prism, and horizontally and continuously scanning the luminous flux of the emitted light. SOLUTION: A laser diode(LD) 10 generates an emitted light L1 in reply to an emission signal, and a light receiving element 90 receives a reflected light L2 based on the emitted light 11 and inputs it to a CPU. The CPU and distance arithmetic part solves a prescribed numerical expression from the time difference between the generating timing of the emitted light L1 and the receiving timing of the reflected light L2 to calculate the distance of an object. A horizontal scanning means 40 for transmitting and refracting the emitted light 11 from a light emitting means 30 is formed of a spiral prism whose apex is continuously changed, and directly connected to the rotating shaft 52 of an actuator 50. The horizontal scanning means 40 is rotated within the vertical plane in cooperation with the rotating shaft 52 to horizontally deflect and scan the luminous flux of the emitted light L1. Thus, most of the time for one scanning period can be used for distance measurement.