Pyroelectric infrared sensor-based thermometer for monitoring indoor objects

This article describes a system for measuring temperature by monitoring an object’s radiation in the infrared spectrum. Using a measuring device by passing through a data acquisition interface, a long-term observation of the temperature variance of objects on a personal computer by the LabVIEW software is conducted. A special mechanism joined with a pyroelectric infrared (PIR) sensor, optical chopper, and Fresnel lens is presented in this system. This separable architecture makes the lens easily replaceable and portable. In this study, the PIR sensor into a quantitative measurement for long-term and long-distance applications with calibration equipment based on a blackbody and some electrometers was successfully applied. Experimental results show that the measuring device only has an average error rate of 1.21% in the overall range from 40 to 200 °C, and field of view is 4.58°. The results confirm that noncontacted temperature measurement using a PIR sensor is feasible.