Infrared sensors are electro-optical devices that convert thermal radiation received into an electrical signal to give a temperature measurement. These systems can be used in many applications: in the security sector, for surveillance purposes, and the civilian sector, for industrial non-contact thermal monitoring. From the basic pyrometers to more complex IR imaging systems, these devices have to be accurately tested, during the development phase, as well as during manufacturing and commissioning. They have to be calibrated prior to delivery and then periodically in the field.

There is a wide range of parameters that can be tested to evaluate the performance of a thermal sensor. For example: MRTD (Minimum Resolvable Thermal Difference), TOD (Triangle Orientation Discrimination), NETD (Noise Equivalent Temperature Difference), fixed pattern noise, MTF (Modulation Transfer Function), spatial resolution, FOV, distortion, optical axis alignment, dynamic range, saturation level, temperature stability, uniformity, etc.