Digital micromirror devices (DMDs) are spatial light modulators that employ the electro-mechanical movement of miniaturized mirrors to steer and thus modulate the light reflected off a mirror array. Their wide availability, low cost and high speed make them a popular choice both in consumer electronics such as video projectors, and scientific applications such as microscopy. High-end fluorescence microscopy systems typically employ laser light sources, which by their nature provide coherent excitation light. In super-resolution microscopy applications that use light modulation, most notably structured illumination microscopy (SIM), the coherent nature of the excitation light becomes a requirement to achieve optimal interference pattern contrast. The universal combination of DMDs and coherent light sources, especially when working with multiple different wavelengths, is unfortunately not straight forward. The substructure of the tilted micromirror array gives rise to a blazed grating, which has to be understood and which must be taken into account when designing a DMD-based illumination system. Here, we present a set of simulation frameworks that explore the use of DMDs in conjunction with coherent light sources, motivated by their application in SIM, but which are generalizable to other light patterning applications. This framework provides all the tools to explore and compute DMD-based diffraction effects and to simulate possible system alignment configurations computationally, which simplifies the system design process and provides guidance for setting up DMD-based microscopes.

This article is part of the Theo Murphy meeting ‘Super-resolution structured illumination microscopy (part 1)’.

数字微镜器件 (DMD) 是一种空间光调制器，它利用小型化镜的机电运动来控制并调制从镜阵列反射的光。它们的广泛可用性、低成本和高速使它们成为视频投影仪等消费电子产品和显微镜等科学应用的热门选择。高端荧光显微镜系统通常采用激光光源，其本质上提供相干激发光。在使用光调制的超分辨率显微镜应用中，尤其是结构照明显微镜 (SIM)，激发光的相干特性成为实现最佳干涉图案对比度的必要条件。DMD 和相干光源的通用组合，尤其是在处理多个不同波长时，不幸的是不是直截了当的。倾斜微镜阵列的子结构产生了闪耀光栅，在设计基于 DMD 的照明系统时必须理解和考虑到这一点。在这里，我们提出了一组模拟框架，这些框架探索了 DMD 与相干光源的结合使用，受其在 SIM 中的应用的启发，但可推广到其他光图案化应用。该框架提供了所有工具来探索和计算基于 DMD 的衍射效应，并通过计算模拟可能的系统对准配置，从而简化了系统设计过程并为设置基于 DMD 的显微镜提供了指导。

本文是 Theo Murphy 会议“超分辨率结构照明显微镜（第 1 部分）”的一部分。