Fresnel Lens SB-F-04

Fresnel lens are widely used in human body induction switch, alarm, infrared thermometer and infrared imaging and other aspects. Can provide users with different induction Angle, induction distance, size, test ratio. Fresnel lens action: First is focusing action; Second, the detection area is divided into a number of bright areas and dark areas, so that the moving objects entering the detection area can generate changes in the form of temperature changes on the PIR (passive infrared detector).