Design of a uniform illumination lens based on the hypothetical point source ensemble method

Uniform distribution plays an important role in illumination design, and the design of uniform lenses for Lambertian light sources remains a challenging problem. An HPE method for designing a compact uniform illumination lens is proposed, where a uniform secondary light source is designed as the inner surface, and the outer surface is designed based on the energy-mapping method. After numerical calculation and fitting, a hyperbolic surface uniform illumination lens is obtained. The results show that the initial lens can achieve 85% illumination uniformity, energy utilization is improved by 36%, and the optimized extended LED source lens can achieve 98.32% uniformity and 91.17% energy utilization under compact size. The optimized point source lens can achieve 96.7% uniformity and 99.55% energy efficiency. The lenses are applied for near and far illumination applications and are suitable for rectangular light sources.