Wang Kai, Wu Dan, Qin Zong, Chen Fei, Luo Xiaobing, Liu Sheng
Division of MOEMS, Wuhan National Laboratory for Optoelectronics, College of Optoelectronics Science and Engineering, Huazhong University of Science & Technology, Wuhan 430074, China.
Opt Express. 2011 Jul 4;19 Suppl 4:A830-40. doi: 10.1364/OE.19.00A830.
In light-emitting diode (LED) applications, it is becoming a big issue that how to optimize light intensity distribution curve (LIDC) and design corresponding optical component to achieve uniform illumination when distance-height ratio (DHR) is given. A new reversing design method is proposed to solve this problem, including design and optimization of LIDC to achieve high uniform illumination and a new algorithm of freeform lens to generate the required LIDC by LED light source. According to this method, two new LED modules integrated with freeform lenses are successfully designed for slim direct-lit LED backlighting with thickness of 10mm, and uniformities of illuminance increase from 0.446 to 0.915 and from 0.155 to 0.887 when DHRs are 2 and 3 respectively. Moreover, the number of new LED modules dramatically decreases to 1/9 of the traditional LED modules while achieving similar uniform illumination in backlighting. Therefore, this new method provides a practical and simple way for optical design of LED uniform illumination when DHR is much larger than 1.
在发光二极管（LED）应用中，当给定距离-高度比（DHR）时，如何优化光强分布曲线（LIDC）并设计相应的光学元件以实现均匀照明正成为一个重大问题。提出了一种新的逆向设计方法来解决这个问题，包括LIDC的设计和优化以实现高均匀照明，以及一种用于由LED光源生成所需LIDC的自由曲面透镜新算法。根据该方法，成功设计了两个集成自由曲面透镜的新型LED模块，用于厚度为10mm的超薄直下式LED背光源，当DHR分别为2和3时，照度均匀度从0.446提高到0.915，从0.155提高到0.887。此外，新型LED模块的数量大幅减少至传统LED模块的1/9，同时在背光源中实现了相似的均匀照明。因此，当DHR远大于1时，这种新方法为LED均匀照明的光学设计提供了一种实用且简单的方法。
