An Infrared Sensor for Large Area Temperature—To Avoid the Influence of Height

Infrared sensors are able to measure the temperature of specific objects on-line, with advantages of high sensitive, non-contact and high precision. Through adjusting the optical systems and enhancing the field of view, the infrared sensors can measure the average temperature of a large area. However, because of the influence of the transmission of infrared emissions in air and the emissions of atmosphere, the measuring distance brings an error in the measuring results. In this study, we developed a temperature sensor that could avoid the influence of the measuring height. We analyzed the physical processes of infrared sensor for large area temperature measurement and proposed a method to compensate the influence of the measuring height by a regression between the infrared signals and distances. An experiment was carried out and a mathematics compensation model was built. And then, we developed a new sensor for large area temperature measurement, using infrared detector combined with a high precision height sensor. Then, the distances between the detector and the measuring objects could firstly be measured and then to compensate the infrared signal. The influence of height was avoided using the new sensor.