| 摘要 |
<p>PURPOSE:To detect a human body with high accuracy with simple and inexpensive constitution, by constituting a scanning optical system, of a cylindrical mirror whose one direction is a concave surface for limiting the width of an instantaneous visual field, and a scanning mirror for scanning one-dimensionally the instantaneous visual field. CONSTITUTION:A scanning optical system 1 for scanning a visual field of an infrared-ray detecting element 2 is provided with a cylindrical mirror 11 whose at least one direction is a concave surface for limiting the width Fw of an instantaneous visual field F, and a scanning mirror 12 for scanning one- dimensionally the instantaneous visual field F formed by the cylindrical mirror 11, in the direction roughly vertical to the longitudinal direction. An output of the infrared-ray detecting element 2 is amplified by a preamplifying part 3, passes through a signal processing part 4 and sent to a deciding part 5. Subsequently, by extracting a peak point, etc., whether the human body exists or not, the position of the human body, and the number of persons are detected. In such a way, the human body can be detected with high accuracy with simple constitution.</p> |
