| 摘要 |
<p>PURPOSE:To enhance the accuracy of detecting a temperature by correcting a temperature value with the temperature of a Fresnel lens in the case of detecting the temperature of a detection area based on the detected value of an infrared sensor. CONSTITUTION:The quantity of infrared light from the detection area 2 set in a specified space 1 in a room is condensed on the infrared sensor 11 by the Fresnel lens 10. Based on output from the infrared sensor 11, the quantity of the infrared light from the detection area 2 is arithmetically operated by a light quantity arithmetic operation means 50. After the value of the quantity of the infrared light is arithmetically operated to be converted into the temperature value of the detection area 2 by a conversion means 51, a signal concerning the specified infrared ray is outputted by a signal processing means 53. In such a case, since a lens temperature detecting means Th1 for detecting the temperature of the Fresnel lens 10 is arranged and the arithmetically operated value of the conversion means 51 is corrected based on the detected temperature, the effect of the radiant heat of the Fresnel lens 10 in which the temperature rises because of the absorption of the infrared ray is considered and the accuracy of detecting the temperature of the detection area 2 is enhanced.</p> |
