Neudert Andreas, Duerr Peter, Nitzsche Mario
Fraunhofer Institute for Photonic Microsystems IPMS, Maria-Reiche Str. 2, 01109 Dresden, Germany.
Micromachines (Basel). 2024 Jul 24;15(8):942. doi: 10.3390/mi15080942.
We are developing a phase-modulating micro mirror-array spatial light modulator to be used for real holography within the EU-funded project REALHOLO, featuring millions of pixels that can be individually positioned in a piston mode at a large frame rate. We found earlier that an electrostatic comb-drive array offers the best performance for the actuators: sufficient yoke forces for fast switching even at low voltages compatible with the CMOS addressing backplane. In our first design, the well-known electrostatic cross-talk issue had already been much smaller than would have been possible for parallel-plate actuators, but it was still larger than the precision requirements for high-image-quality holography. In this paper, we report on our analysis of the crucial regions for the electrostatic cross-talk and ways to reduce it while observing manufacturing constraints as well as avoiding excessively high field strengths that might lead to electrical breakdown. Finally, we present a solution that, in FEM simulations, reduces the remaining cross-talk to well below the required specification limit. This solution can be manufactured without any additional processing steps and suffers only a very small reduction of the yoke forces.
我们正在欧盟资助的“REALHOLO”项目中开发一种用于实时光全息术的相位调制微镜阵列空间光调制器，它具有数百万个像素，能够以大帧率在活塞模式下单独定位。我们之前发现，静电梳齿驱动阵列在致动器方面表现最佳：即使在与CMOS寻址背板兼容的低电压下，也能提供足够的磁轭力实现快速切换。在我们的首次设计中，众所周知的静电串扰问题已经比平行板致动器可能出现的情况小得多，但仍大于高图像质量全息术的精度要求。在本文中，我们报告了对静电串扰关键区域的分析以及在遵守制造限制并避免可能导致电击穿的过高场强的同时降低串扰的方法。最后，我们提出了一种解决方案，在有限元模拟中，该方案可将剩余串扰降低到远低于所需规范限制的水平。该解决方案无需任何额外的加工步骤即可制造，且磁轭力仅略有降低。
