The fresnel lens is a flat and slim optical lens are different with traditional glass lens which is heavy and thicker, it is originally developed by French physicist Augustin-Jean Fresnel for lighthouses.
The fresnel lens made by many engraved groove on the flat plate which Each groove is at a slightly different angle than the next and with the same focal length in order to focus the light toward a central focal point. Every groove can be considered as an individual small lens to bend parallel Fresnel light waves and focus the light.
Fresnel lenses are usually made of glass or plastic; their size varies from large to small. In many cases Fresnel lens are very thin and flat, almost flexible, with thicknesses in the 1 to 5 millimetre range. Fresnel lens can uses as lighting, fresnel lamp, overhead projector, Fresnel magnifier,DIY Fresnel TV projection, camera fresnel spotlight, automobile headlight lens cover, fresnel lens solar energy, rear projection Fresnel screen, PIR passive motion detector lens, fresnel traffic sign lens, fresnel lens photovoltaic, fresnel solar concentrator, fresnel flight simulator and LED magnifier.