The Mini White Fresnel Lens, named after the French physicist Augustin-Jean Fresnel, is a compact and lightweight lens commonly utilised in motion sensors. Unlike conventional lenses, this type of lens boasts a unique design featuring concentric grooves or ridges on its surface, acting as separate lens elements. These ridges assist in focusing infrared radiation onto a sensor, such as a pyroelectric sensor, by collecting and concentrating the emitted radiation from objects within the sensor's field of view. The design of the Mini White Fresnel Lens allows it to cover a broad field of view, enabling motion detection over a large area.
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