| 摘要 |
PROBLEM TO BE SOLVED: To prevent the irradiation of strong light to a human being more securely by an inexpensive and small device without causing a malfunction to things other than human being. SOLUTION: A safety card 11 carried by a human being near light projected by a projector 1 to display an image on a screen, computes a distance between the safety card 11 and a communication device 14 on the basis of a signal transmitted from the communication device 14, and computes a distance between the safety card 11 and a control unit 13 provided at the projector 1 on the basis of a signal transmitted from the control unit 13. Then, the safety card 11 calculates its own position on the basis of the two computed distances, and transmits a signal indicative of the position of the safety card 11 to the control unit 13. The control unit 13 receives the signal from the safety card 11, and instructs the projector 1 to reduce the luminous intensity of light if the position of the safety card 11 contained in the signal is within a region of projected light. The present invention is applicable to a projector. COPYRIGHT: (C)2006,JPO&NCIPI |
