| 摘要 |
<p>PURPOSE:To effect positive discriminative detection of a person and other objects. CONSTITUTION:Cylindrical lens-barrels 5, 6 not transmitting infrared rays are provided with concave reflecting mirrors 7, 8. Through the respective concave reflecting mirrors 1, 8, infrared rays from an object are converged on an infrared sensor 1 and an infrared sensor 2 being transmitted through an infrared region transmission filter 3 with a wide wavelength band of 8-13mum and an infrared region transmission filter 4 with a narrow wavelength band of 9-10mum with the peak wavelength of radiation intensity of infrared rays radiated from a person as the approximate center. In a microcomputer 11, the output voltage of the infrared sensor 1 is compared with the voltage reference value corresponding to a human body, stored in a memory 12, and the voltage ratio of the infrared sensors 1, 2 is further compared with the voltage ratio reference value so as to discriminate a person from an object utilizing the fact that the degree of infrared radiation intensity is different from the peak wavelength.</p> |
