30 Years of Passive Infrared Motion Detectors - a Technology Review

Infrared detection in military applications and pyrometry has a long history. Although some more recent IR applications like fiber optics communication or focal plane arrays for imaging have rapidly evolved in the last decades, PIR motion detection technology went its own way, and has not much in common with other infrared applications at 10 microns wavelength, due to the requirements for low cost and room temperature operation. The PIR market has reached an estimated annual volume of close to 100 million units today, but it is still a small and confined market, and was over most of the years out of the interest of technological investments.