A fast freeform surface design method based on feature mapping

Designing freeform optical surfaces to generate the expected irradiance distribution on the image plane remains a core challenge in non-imaging optics. To address this, we propose a freeform optical surface modeling technique based on B-splines curves and interpolation. Compared to traditional ray tracing methods, our approach significantly reduces computation time and minimizes redundant calculations. While the majority of current optical research is directed toward achieving higher precision and resolution, our method deliberately trades a certain degree of accuracy for improved computational efficiency. This makes it particularly suitable for applications prioritizing rapid response and real-time operation over micrometer-level accuracy, notably indoor lighting design and optical sensing. These fields are expected to benefit greatly from our approach.