| 摘要 |
PURPOSE:To enable highly accurate measurement with a simple construction, by arranging two targets with a specified radiation intensity in an infrared rays region, the one at a far distance and the other at a close distance separately. CONSTITUTION:Two targets with a specified radiation intensity are arranged in an infrared rays area, the one, heat plates 21 at a far distance and the other, heat plates 22 at a close distance separately and the apparent size of the heat plates 21 and 22 is set the same as viewed from an infrared rays video device 23 to obtain video signals S1 and S2 and S10 and S20. In operation, the heat plates 21 and 22 with the temperatures T1 and T2 and T10 and T20 arranged at two points, far and close, are observed with the device 23 to determine video signal intensities per unit temperature of the heat plates by a first specified formula from video signal intensities S1 and S2 obtained when a scan line crosses over a pair of heat plates 21 and signal intensities S10 and S20 obtained when the same scan line scans a pair of heat plates 22. Then, using a second specified formula, an attenuation coefficient of atmospheric air is obtained. These calculations can be programmed with a simple calculator. |
