| 摘要 |
PURPOSE:To measure a temperature accurately even if surrounding temperature is varied, by using two oscillators for which an elastic surface acoustic wave is used and detecting infrared rays on the one hand and also detecting the surrounding temperature on the other hand to correct the detected output of the infrared rays. CONSTITUTION:The one hand detecting part 6 performs the duty of photodetecting infrared rays from a material to be measured and on the other hand, detecting part 7 performs the duty of detecting surrounding temperature. Here, it is constituted that both temperature variations differ each other by selecting a kind of a cut direction of a piezoelectric body substrate. When infrared rays 5 are irradiated to an infrared detecting part 6, an output of an oscillation frequency f1 in accordance with the infrared rays is generated. The oscillation frequency f1 is affected by the surrounding temperature. On one hand, the surrounding temperature detecting part 7 is not irradiated by the infrared rays and the output of an oscillation frequency f2 in accordance with the surrounding temperature is generated. The outputs of these detecting parts 6, 7 are applied to a mixer 8 and the difference of the frequency f1-f2 is obtained at a terminal 9. The surrounding temperature of the detecting parts 6, 7 can be detected from a portion of frequency variation and the temperature is corrected by this value. |
