Study on optical design method for LED extended sources

Abstract

Conventional LED optical design method that is commom for the point source approximation based on energy conservation and the law of refraction and reflection, and the final optical model solved by stepping method. The method that plays an important role in the LED second optical design is not applicable to the LED extended sources. In this paper, the optical design method is present for LED extended sources by using edge ray theorem, and light intensity optical model has be established by this method. The optical simulation results of uniform light intensity curve of the model are compared with the models designed by approximate design method of point source. The results show that the directions of outgoing light lines can be controlled more accurately by edge ray theorem and have better uniformity. The method can be applied for the LED encapsulation optical system design and multi-chip source optical design of high-power LED. It can improve the design accuracy and save design cost.