Neptune production of human infrared sensor switch infrared sensor with Fresnel lens 8090

Products Fresnel lens by French physicist Augustin Fresnel (Augustin.Fresnel) invention, in 1822, he initially used this lens is designed to build a glass Fresnel lens system - Lighthouse lens. Lens (0.7mm thick) surface burned a circle of small to large, concentric circles outward from shallow to deep, from the profile appears jagged. More dense induction circular line angle, focal length away; it burns deep circular line should distance, focal length close. The more infrared light into concentric rings of light against the more concentrated and stronger. Several concentric rings on the same line to form a vertical sensing area, consisting of a horizontal segment between induction concentric rings. The more vertical sensing area Vertical sensing angle greater; the more the longer the induction segment angle lens, the greater the level of induction. Number of multi-sector body movement is sensed amplitude is small, the number of zones and less range of movement is sensed body gets on. Interleaved between the concentric circles of different regions, reducing blind spots between the segments. Between the district and the district, between paragraphs, between the sections forming blind. Since the lens is restricted angular field of view of infrared sensor, sensing the vertical and horizontal angle is limited, the lens area is also limited. Lens appearance classified as: a long, square, round, from the functional classification are: single-zone multi-stage, dual-zone multi-stage, multi-zone multi-segment. Fresnel lens has two functions: one focusing effect, pyroelectric infrared signal coming refraction (reflection) on the PIR, the second role is within the detection area is divided into a number of bright and dark regions, entering the detection area a moving object in the form of temperature change can make a difference pyroelectric infrared signal at PIR.