| 摘要 |
<p>PURPOSE: To observe a target secretly by irradiating the target with an infrared rays of such frequency band as exhibiting lowest conductivity under specified atmospheric conditions. CONSTITUTION: This system comprises an unit for irradiating target with an infrared rays having frequency band selected to exhibit lowest conductivity under specified atmospheric conditions, and a unit for detecting the reflected infrared rays having selected frequency band. More specifically, an illuminator 10 illuminates a target with infrared rays and reflected infrared rays are detected by a light receiving unit 12 and monitored by a monitor 14. According to the arrangement, the target can be observed secretly.</p> |
