Patent ID: 7362258

Claim:
A target object detection system for detecting a target object in a surrounding area of a detector using a tag provided on the target object, wherein the tag comprising: a radio wave receiver receiving radio wave transmitted from the detector; a light receiver receiving an infrared light signal irradiated from the detector; a receipt signal generator generating a receipt signal only when the light signal from the detector is received within a predetermined time after receiving radio wave; and a transmitter which transmits by wireless the receipt signal to the detector; and the detector comprising: a radio wave transmitter transmitting the radio wave to the surrounding area of the detector; a receiver receiving the receipt signal transmitted from the tag; a light emitter irradiating the light signal to a search region established around the detector; a controller controlling the radio wave transmitter, the receiver, and the light emitter; and a target position measuring unit measuring a distance from the detector to the target object based on the intensity of the receipt signal when the receipt signal is received by the receiver, and the target position measuring unit regarding the irradiation direction of the light signal from the light emitter as the direction of the target-object.