Design of belt-type Fresnel lens with image surface of uniform illuminance

In order to solve the problem of nonuniform distribution of light intensity on the receiving surface of solar cells after the solar light was collected by the conventional Fresnel concentrator, a belt type Fresnel concentrator was designed.According to the Fresnel belt design method, the receiving surface was divided into corresponding zones, which made the light first pass through the surface belt of Fresnel condenser then enter the corresponding receiving surface strip, so as to reduce the optic energy loss and improve the uniformity of light intensity distribution.This paper gave an example of Fresnel condenser system with the solar flare angle of 0.54°, the diameter of 200 mm, the height width ratio of 0.65 and the concentration ratio of 400 in the wavelength range of 350 nm~760 nm, simulated and analyzed the optic capability of Fresnel condenser by Tracepro.Results show that compared with traditional uniform Fresnel lens condenser of the same parameters and in the case of the same size receiving surface, the spot energy distribution uniformity of the belt-type Fresnel lens reaches 75%.