基于自由曲面透镜的高品质LED光源设计与制造

This project is focused on the continuously increasing of high quality light emitting diode (LED) lighting market and the technical bottleneck which has brought significant impediments to the applications of LEDs. The project studies the design and fabrication of free-form lenses for LED lightings. The energy transfer model of a LED illumination system is established, and the mismatch mechanism of a LED point-lighting free-form lens in the application of an extended-source is investigated. A novel design methods named “energy feedback freeform lens”（EFFL）method is proposed, and a free-form lens for LED extended-sources is developed and tested. Moreover, this projected studies the LED phosphor coating structures and their manufacturing methods. The mechanism of the pause-sprayed coating process is investigated, and two composite coating structures including the multi-layer structure and the remote conformal structure are developed. In order to further improve the LED light extraction efficiency and its diffusion characteristics, a layer of micro-nano-scale optical functional structure is fabricated on the phosphor coating. Finally the overall photoelectric properties of LEDs are measured, and the components experience a reliability evaluation for obtaining higher lighting quality.

本课题针对高品质LED光源日益增长的实际需求以及制约LED照明应用推广的技术瓶颈，研究LED扩展光源自由曲面透镜设计与制备技术。建立照明系统能量传递模型，基于点光源——扩展光源配光误差，提出具有能量反馈函数的LED自由曲面透镜（EFFL）算法，完成透镜设计，利用一体塑封成型工艺制备LED自由曲面透镜；深入研究了光源荧光涂层结构及其制备工艺，分析了脉冲喷射涂层材料液滴成型机理，设计多层荧光涂层与远程保形荧光涂层复合结构，并利用微机械压印技术，在荧光涂层表面制造出微纳尺度光功能结构，提高LED荧光涂层出光效率及散射特性；最后通过对LED光源实施光电性能综合测试以及可靠性工程，优化光源制造中，芯片安放、金线键合、齐纳保护等关键工艺过程，进一步提高光源品质，最终促进LED照明产业技术升级，推动半导体照明技术普及。

本课题针对高品质LED光源日益增长的实际需求以及制约LED照明应用推广的技术瓶颈，研究LED扩展光源自由曲面透镜设计与制备技术。提出了照明系统光源-透镜-被照面能量传递模型，建立起基于LED点光源的自由曲面光学透镜设计理论；基于点光源——扩展光源配光失效机理，提出了具有能量反馈函数的LED自由曲面透镜（EFFL）算法，完成透镜设计，优化一体塑封成型工艺并制备出高精度LED自由曲面透镜。提出了多粉体复合荧光涂层的光学模型，揭示了多粉体组配对白光LED光色性能的影响；基于该光学模型，分别提出了针对点光源/拓展光源的自由曲面荧光涂层光色反馈设计方法；分析了脉冲喷射涂层材料液滴成型机理，建立了喷涂涂层形貌与内建透镜曲率的映射关系，设计出透镜复合自由曲面荧光涂层结构，提升光源光色品质。对LED光源实施光电性能综合测试以及可靠性工程，优化芯片安放、金线键合等关键工艺过程，分析器件外加机械载荷失效机理及脉冲驱动循环工作热失效机理，进一步提高光源品质。最终形成一套完整的基于自由曲面透镜的高品质LED光源设计、制造理论体系，促进LED照明产业技术发展。