Patent ID: 7848033

Claim:
Apparatus, for concentrating light rays arriving from at least one opening onto a receiver, said light rays originating from at least one source external to said apparatus, the distance between the at least one source of said light rays and said apparatus being substantially larger than the size of said opening, individual beams of said light rays thereby each arriving at said apparatus substantially collimated, comprising: a respective Fresnel lens assembly for each said at least one opening, said at least one respective Fresnel lens assembly including: a first Fresnel lens, located between a respective one of said at least one opening and said receiver, for making parallel with an optical axis of said first Fresnel lens, said light rays arriving from said respective one of said at least one opening; and a second Fresnel lens, located between said first Fresnel lens and said receiver, for converging said parallel light rays onto said receiver, wherein each said at least one opening is located in front of said respective Fresnel lens assembly, on the focal plane of said respective first Fresnel lens, centered on the focal point of said respective first Fresnel lens, wherein said receiver is located behind each said at least one respective Fresnel lens assembly, on the focal point of the respective said second Fresnel lens, wherein, for each said respective Fresnel lens assembly, the distance from said respective one of said at least one opening to said receiver is approximate to the accumulated distance of the focal length of said respective first Fresnel lens, the focal length of said respective second Fresnel lens and the space between said respective first Fresnel lens and said respective second Fresnel lens, wherein said space is substantially zero.