DMD微镜非线性特性数值模拟

Nonlinear Characteristics Analysis of a DMD Micromirror

DMD微镜系统的动态特性分析是非常复杂的,这是因为在系统中存在静电和机械两个非线性耦合的物理场。文中首先分析了无阻尼微镜系统的固有频率;然后采用直接积分法详细分析了系统的相轨迹曲线以及系统的正弦激励响应,通过数值模拟发现系统的相轨迹存在一个稳定点和一个非稳定平衡点;在正弦激励下,系统的共振频率随施加电压增大而减小、振动平衡位置随电压增大发生偏移等现象。

The dynamic analysis of a DMD micromirror system is very complicated in the fact that there are two physical domains, electrical and mechanical, with nonlinear coupling between them. In this paper, firstly, the nature frequency of a DMD micromirror system is investigated. Then, the phase trajectories and the steady harmonic responses of a DMD micromirror are numerically simulated with a direct integral method. Some nonlinear phenomena are observed in this paper, i.e., that the resonant frequency is reducing with applied voltage increasing, that there are two balance points in the phase trajectories, and that the larger the voltage amplitude applied to the micromirror, the further is the shifting of the mean harmonic steady responses. Study of these phenomena is helpful to design torsion micromirror systems and extend the usage of a micromirror system.