中文摘要：

传统的自由曲面透镜建模通常需要多个软件共同协作完成,其建模过程繁琐,且由于不同软件之间的不兼容会导致模型在导入光学仿真软件时出现微小形变。提出一种在光学仿真软件中利用Scheme语言直接进行快速建模的LED自由曲面透镜建模方法。根据光源辐射特性和需要实现的照明面上的能量分布,采用划分网格法,利用Snell方程和能量守恒定律,沿经纬方向分别迭代求解,在得到自由曲面各节点坐标后,分别采用3D建模软件和Scheme语言编程构建透镜模型。通过光学仿真软件,模拟计算了100万条光线,直径1mm的光源在距离地面10 m、面积为40 m×10 m的照明区域内的照度分布。结果表明：利用Scheme语言在光学仿真软件中直接快速建模避免了模型从3D软件导入光学仿真软件时产生的微小形变从而使光照均匀度由67%提升到93.5%。同时Scheme语言编程建模仅需5 s,建模速度远高于3D建模软件。

英文摘要：

Multiple softwares were required in the traditional design process of LED free-form surface lens. It is obvious that this process is complicated and inefficient. Moreover, when the model was transferred from 3D modeling software to optical simulation software, the file format had to be changed to solve the problem Of the software compatibility. Note that some subtle changes were inevitably introduced to the model by such an operation, such as the generation of cracks or tiny deformation which would seriously affect the light efficiency and the degree of illumination uniformity. A new design method was presented in this paper which was used to directly generate model in the optical simulation software by using Scheme language. In this paper, the method of mesh division was applied to design the LED free-form surface lens with rectangular lighting. After the corresponding surface configuration was obtained, 3D modeling software and the Scheme language programming were used to generate lens model respectively. With the help of optical simulation software, a light source with the size of 1 mm in diameter was used in experiment, in which total one million rays were computed. The simulated results could be acquired by both models. It can be seen that the model deformation problems caused by the process of the model transfer could be prevented by using Scheme language, and the degree of illumination uniformity was also increased from 67% to 93.5%. Meanwhile, only 5 seconds were needed in modeling process by Scheme language which was more efficient than 3D modeling software.