Shaped nonimaging Fresnel lenses

Shaped nonimaging Fresnel lenses have been designed according to the edge-r ay principle, incorporating any combination of two acceptance half-angle pa irs. A numerical solution yields nonimaging lenses consisting of minimum-de viation prisms. If the outer surface of the lens must be smooth, the lens s hape will be convex. A linear lens prototype intended as concentrator for t he collection of solar energy has been designed, manufactured and tested. R esults in terms of flux distribution and the optical concentration ratio ar e presented. Shaped nonimaging Fresnel lenses are suited for application as solar concentrators, or as collimators, or in Lighting applications, where they can fulfil technological requirements as well as being adaptable to t he necessities of fashionable design.