The design of a reading light system with RGB white light LED by Fresnel lens and evolutionary algorithms

This paper presents the design of a reading light system consisted of multiple R, G, and B white light LEDs with Fresnel lens located before the light source. First, we use a general Fresnel lens and a Genetic Algorithm (phase I) to search the best arrangement of multiple LEDs, then use another Genetic Algorithm (phase II) to the result obtained before to get a better Fresnel lens of width-varied grooves. Experimental results show that the special arrangement of LEDs and the special structure of Fresnel lens make the reading light system more efficient in illuminance than the reading light system of no Fresnel lens.