We provide a compact 200 line MATLAB code demonstrating how Topology Optimization (TopOpt) as an inverse design tool may be used in photonics, targeting the design of two-dimensional dielectric metalenses and a metallic reflector as examples. The physics model is solved using the finite element method and the code utilizes MATLABs fmincon algorithm to solve the optimization problem. In addition to presenting the code itself, we briefly discuss a number of extensions and provide the code required to implement some of these. Finally, we demonstrate the superiority of using a gradient-based method compared to a genetic-algorithm-based method (using MATLABs ga algorithm) for solving inverse design problems in photonics. The MATLAB software is freely available in the paper and may be downloaded from https://www.topopt.dtu.dk.

中文翻译：

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用于通过拓扑优化进行光子学逆向设计的 200 行 MATLAB 代码

我们提供了一个紧凑的 200 行 MATLAB 代码，展示了如何将拓扑优化 (TopOpt) 作为逆向设计工具用于光子学，以二维介电元透镜和金属反射器的设计为例。物理模型采用有限元法求解，代码采用MATLABs fmincon算法求解优化问题。除了展示代码本身，我们还简要讨论了一些扩展，并提供了实现其中一些扩展所需的代码。最后，我们证明了使用基于梯度的方法与基于遗传算法的方法（使用 MATLABs ga 算法）相比在解决光子学中的逆向设计问题方面的优越性。MATLAB 软件在论文中免费提供，可以从 https://www.topopt.dtu.dk 下载。