Study On The Electromechanical Characteristic And Control System Of Grating Light Modulator Based On MEMS

Due to the advantages of high light efficiency, fast modulating speed, great gray scales, excellent contrast, high brightness and good uniformity, light modulator based on MEMS technology has become one of the focus research projects in the field of large screen high definition projection display. Because of the patent protection for the existing light modulators, the research and development of domestic projection display technology is limited, so it is sharply necessary to develop a new light modulator with own patent property right. For this new light modulator proposed by research group, the electromechanical characteristics such as operation voltage, natural frequency and response speed are the key performance, which decide whether the device can be used in the field of projection display. In this dissertation, the structure, electromechanical characteristics and drive control system of the new light modulator are researched and investigated. The main contributions include the following:① The principles and features of the existing light modulator base on MEMS technology are reviewed and discussed firstly. According to the disadvantages of the existing technology, two new grating light modulators (GLM) are proposed: Reflector-moving GLM and Grating-moving GLM. The structures and operation principles of these two GLM are introduced in detail.② Applying the mechanics theory for micro-structure, the corresponding electrodynamics' models are gained; the relations between the electromechanical characteristics and the structure parameters of the device are analyzed theoretically and simulated by CoventorWare. The structures of GLM are optimized to achieve a larger efficient diffracting area and practicable parameters of GLM are gained. Then 4x4 and 16×16 GLM arrays are fabricated, and some of them are tested and analyzed by the interfere contourgragh WYKO NT11100. The results show that due to the limitation of the existing processing technic, only GM-GLM can be achieved in a good result but still needs further improvement.③ According to the special electromechanical characteristics of GLM, the drive manner for GLM and implementation way for image gray are determined. The general scheme of the GLM display control system is developed. As to the obtained 16x16 GLM array, the data format transformation and pulse width modulation (PWM) modules of the display control system are concretely designed by using the VHDL...