The ray mapping method for freeform illumination design is an easy and flexible method, but only in the paraxial regime does it result in surface normal fields that are directly integrable into continuous freeform surfaces that provide the desired illuminance distribution. A new mapping scheme is proposed to alter an initial source-target mapping via a symplectic flow of an equi-flux parametric coordinate system. The resulting mapping provides integrable surface normal vector fields for complex off-axis and non-paraxial illumination problems, as demonstrated by two freeform lens examples.

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离轴和非傍轴自由曲面照明透镜设计的射线映射方法

用于自由形式照明设计的射线映射方法是一种简便且灵活的方法，但是只有在近轴状态下，它才会导致表面法线场直接集成到连续的自由形式表面中，从而提供所需的照度分布。提出了一种新的映射方案，通过等通量参数坐标系的辛流来改变初始的源-目标映射。生成的映射为复杂的离轴和非傍轴照明问题提供了可积分的表面法线矢量场，如两个自由曲面镜头示例所示。