What is a Fresnel magnifying glass?

This is a super thin magnifying glass Fresnel optical lens.Fresnel magnifying glass made of transparent perspex (of course, you can also use more materials), made of PVC magnifying glass, the minimum thickness can be 0. Today Fresnel lens to explain what is Fresnel magnifying glass: Fresnel optical lens

Fresnel lens.45mm~0, unlike ordinary magnifying glass, makes the light passing through it bend to produce diffraction phenomenon.Thus, a magnifying Fresnel optical lens is formed, and Fresnel plays a very good role in the field of magnifying glass.Achieved the effect of ordinary lens cannot reach, carry, hi the Fresnel optical lens, the characteristics of Fresnel lens is brighter than normal lens and the surface is smooth, Fresnel optical lens of radiating surface area is large. Typically the diameter of the concave and convex lens it is limited. Its surface was covered with tiny stripe Fresnel optical lens, in its spiral stripe contains many convex lens (hereinafter referred to as circular ring).And now the Fresnel magnifier is only 0.Fresnel optical lens between 45mm and 90mm, in fact, the main function is to reduce the weight and volume of ordinary plexiglass and glass magnifying glass made by traditional magnifying glass.