@inproceedings{1fc39e35c9a441c59f6a2d88807e0419,
title = "Spherical-freeform lens design for uniform illumination based on differentiable ray tracing with 'uv' polynomials",
abstract = "We previously optimized the freeform surfaces using extended polynomials in stereographic projection coordinates based on an automated workflow linking the optimization engine, 3D modeling software and ray tracing software [Optics Express 29(9), 13469-13485 (2021)]. However, this method is time consuming as it needs thousands of irradiance evaluations. Here, we speed up the optimization of spherical-freeform lenses for uniform illumination based on differentiable ray tracing. The freeform surface is still parameterized with the 'uv' extended polynomials under stereographic projection coordinates, which is suitable for generating simple illumination patterns. We implement differentiable ray tracing based on computation graph in MindSpore framework, which is efficient and effective by calculating derivatives of the surface parameters during a single backpropagation. We provide two design examples for generating uniform irradiance distributions with a point-like source and an extended light source, respectively.",
keywords = "Differentiable ray tracing, Freeform lens, Illumination optics design",
author = "Haoran Li and Haisong Tang and Zexin Feng and Yi Luo and Yongtian Wang",
note = "Publisher Copyright: {\textcopyright} 2023 SPIE.; Optical Design and Testing XIII 2023 ; Conference date: 14-10-2023 Through 15-10-2023",
year = "2023",
doi = "10.1117/12.2687294",
language = "English",
series = "Proceedings of SPIE - The International Society for Optical Engineering",
publisher = "SPIE",
editor = "Yongtian Wang and Kidger, {Tina E.} and Rengmao Wu",
booktitle = "Optical Design and Testing XIII",
address = "United States",
}