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Design of compact and smooth free-form optical system with uniform illuminance for LED source
Yi Luo1, Zexin Feng, Yanjun Han
1State Key Lab on Integrated Optoelectronics/Tsinghua National Lab on Information Science and Technology, Department of Electronic Engineering, Tsinghua University, Beijing, 100084, P. R. China. luoy@tsinghua.edu.cn
Abstract:
A feedback modification method based on variable separation mapping is proposed in the design of free-form optical system with uniform illuminance for LED source. In this method, the non-negligible size of LED source is taken into account, and a smooth optical system is established with single freeform surface regenerated by adding feedback to the lens design for a point light source. More rounds of feedback can improve the lens performance. As an example, a smooth free-form lens with rectangular illuminance distribution is designed, and the illuminance uniformity is improved from 18.75% to 81.08% after eight times feedback.
