直梁结构光栅光调制器的机电特性分析与实验

Analysis and Experiment of Electromechanical Characteristics of a Straight-Beam Grating Light Modulator

介绍了直梁光栅光调制器的结构和原理,建立了器件的机电模型.利用能量法和卡式第二定理分析并得到器件的弹性系数;通过静电力与机械回复力的平衡,得到器件的驱动电压.结合器件的实际参数值,计算得到器件的工作电压为10.71 V,吸合电压为11.46 V.实验测得器件的实际工作电压为10.5 V,吸合电压为12.2 V,实验结果与理论分析基本一致.在1 kHz脉冲电压的驱动下,器件响应的上升时间和下降时间分别为46.59μs和44.77μs;器件的响应频率约为5 kHz.结果表明,加工的直梁光栅光调制器具有较低的驱动电压和较高的响应频率,能够满足微投影显示的要求.

The structure and operating principle of a straight-beam grating light modulator （GLM） were introduced and the electromeehanical model of the device was established, whose elastic coefficient was obtained using energy method and Castigliano＇ s second theorem. The driving voltage of the device was calculated with balance equation between the electrostatic force and the mechanical restoration force. Considering the real values of the parameters, the operating voltage and the pull-in voltage of the device are 10. 71 V and 11.46 V respectively in theory. In the experiment the operating voltage and the pull-in voltage were 10.5 V and 12.2 V respectively, which was basically in accordance with the theory. When the GLM was actuated by a square-wave voltage with 1 kHz frequency, the rising time and the falling time of its intensity response were about 46.59μs and 44. 77 μs respectively. The response frequency of GLM was about 5 kHz. The results indicate that the fabricated GLM has a low driving voltage and a high response frequency, which can satisfy the need of projection display.