基于LED的自由曲面照明光学系统设计

	基于LED的自由曲面照明光学系统设计
	辛迪
学位类型	博士
导师	卢振武
	2014-07
学位授予单位	中国科学院大学
学位专业	光学
摘要	在当今能源紧缺，环境污染严峻的形势下，新一代照明光源LED以其独特的优势逐渐在各个行业领域占据一席之地，成为节能环保的首选光源。而LED照明领域一个亟待解决的问题就是，如何高效地对LED进行配光设计，从而形成满足应用要求的照明产品。自由曲面照明是一种新型照明方式，设计自由度高，能够灵活调控光束分布，简化照明系统结构，实现复杂照明。因此，越来越多的照明系统以自由曲面光学器件作为LED的配光元件。本课题主要研究的就是如何对LED光源设计自由曲面照明光学系统，对LED发出的光进行高效、可控、低成本地传输和配光。具体研究内容如下：研究了基于能量映射法的自由曲面初始面形结构设计方法。分别针对旋转对称结构和非旋转对称结构光学系统，构建能量映射网格，建立光源光线角度与目标面坐标点或出射光线角度的一一对应关系，分析其对可积条件的满足情况。针对传统的离散面形点计算方法所存在的问题，即拟合后的自由曲面的实际法矢与计算所得的理想法矢存在较大偏差，提出了一种基于面形点位置修正的改进方法，并进行了验证，结果表明，对于旋转对称结构，改进算法几乎可以完全消除该法矢偏离；而对于非旋转对称结构，虽不能完全消除，也能够使其显著减少。光学仿真结果显示，改进算法都能够得到比传统算法更符合设计要求的照明光斑，为优化的顺利进行奠定良好的基础。研究了自由曲面光学系统的优化。由于旋转对称结构和非旋转对称结构产生照明偏差的原因不同，采取不同的优化策略进行优化。对于旋转对称结构，基于二次B样条建立参数化模型。由于初始面形不存在法矢偏离，直接进行基于非序列光线追迹的优化。对于非旋转对称光学系统，基于双三次B样条建立参数化模型。首先基于面形点处实际法矢与理想法矢的偏离构建评价函数，采用模式搜索算法进行初步优化，以减少该法矢偏离，初步改善照明效果。再以初步优化的结果为基础，基于照度均匀性和能量利用率构建评价函数进行优化。结合初始面形结构设计方法与该优化方法，形成了一套有效的自由曲面照明光学系统设计方法，通过理论模拟与实验分析验证了该设计方法的可行性。
其他摘要	With the tightening supplies of energy and deterioration of environment pollution in the global, the new generation of light sources, LEDs, with their advantages of lower power consumption and environmental friendly, are becoming more generally preferred in illumination systems. One of the questions needed to be solved is that how to design the secondary optics of LED to meet the requirements of specific applications. Freeform optical surface is an emerging optical technology with advantages of being high design freedom and being precise light irradiation control. It can simplify the system construction and realize complicated illumination pattern. As a result, more and more illumination systems adopt the freeform surface as the secondary optics. In order to realize the redistribution of the LED light with high efficiency according to the applications, this paper researched on the optical design of freeform surface in LED illumination systems. The specific contents include the following work: The design method of the initial freeform surface based on the energy mapping method was researched. The energy grid patterns were constructed and analyzed based on the integrability condition for both symmetric and non-symmetric systems. In order to solve the problem of the traditional calculation of the discrete points on the surface, which is the real normal vectors deviating from the desired normal vectors, the improved method based on the point position modification was proposed and verified for both symmetric and non-symmetric systems. The improved method can almost eliminate the entire deviation for the symmetric system and decrease that for the non-symmetric system. The simulation results showed that the illumination patterns obtained from the improved method were more close to the design targets. The optimization method was researched. Since the reason why the simulation result deviated from the desired one was different for the symmetric systems and non-symmetric systems, different optimization processes were adopted. For the symmetric system which had no deviation in normal vectors, the parametric model based on the quadratic B spline was constructed and the optimization based on the non-sequential ray tracing was directly carried out. For the non-symmetric systems, the parametric model was constructed based on the bi-cubic B spline. The merit function was first constructed from the deviation between the real normal vectors and the desired normal vectors. The initial optimization was carried out based on the patternsearch algorithm. Then, the optimization to improve the illumination uniformity and optical efficiency was carried out. Combining the initial freeform surface design method with the optimization method, an effective optical design method of freeform surface in illumination system was formed and verified by the simulation and the experiment.
语种	中文
文献类型	学位论文
条目标识符	http://ir.ciomp.ac.cn/handle/181722/41488
专题	中科院长春光机所知识产出
推荐引用方式 GB/T 7714	辛迪. 基于LED的自由曲面照明光学系统设计[D]. 中国科学院大学,2014.

条目包含的文件
文件名称/大小	文献类型	版本类型	开放类型	使用许可
辛迪.pdf（4451KB）			开放获取	CC BY-NC-SA	请求全文