Abstract:
Fresnel lens is one of the most common solar concentrators. The performance of the curved Fresnel lens is usually better than flat Fresnel lens. Based on the principle of non-imaging optics, a new curved Fresnel lens design method was proposed in this study. The curved Fresnel lens was on conical surface. In the premise of meeting the mechanical requirements of the Fresnel lens, the slope of the second surface of the Fresnel lens was solved. Based on the objective of manufacturability, different shapes of Fresnel lenses were obtained by this method to analyze the effect of structural parameters of curved Fresnel lens on concentration ratio, acceptance angle and the illumination uniformity by optical simulation. The effect of machining error on optical efficiency in ultra-precision machining was also analyzed. The design method provided a new way for the parametric analysis of curved Fresnel lens. The simulation results show that the small aspect ratio of curved Fresnel lens will get good uniformity and high energy efficiency.