This article comprehensively describes the properties and operating principles of pyroelectric infrared detector using thin films.

Pyroelectric detector and fast respond infrared radiometer are used in the system to carry on the measurement, and effective data processing method is adopted to improve the test accuracy.

The input and output mathematical model of DIGA (Dispersive Infrared Gas Analyzer) system with pyroelectric detector was established according to the design principle of DIGA.