Summary: | 博士 === 逢甲大學 === 電機與通訊工程博士學位學程 === 100 === With the rapid development of microprojection systems, the laser scanning technique has become the optimal solution for the requirements of portable products, and is easily integrated with electronic devices. In such applications, the micromirror device plays a vital role in laser scanning display and may dominate the projected image quality. In general, a 2D-image can be created by using a laser beam projected on a dual-axis, gimbaled rotation structure or two single-axis scanning units with orthogonal alignment. Therefore, the laser scanning display has a small size, a simple fabrication process, low cost, and high quality in image display. This thesis proposes a novel electromagnetic scanning micromirror device with lateral driving force. A specific design and vacuum packaging performance were also investigated to enhance the efficiency of the devices. The typical design of two single-axis micromirrors for the actuation in low and high frequencies were realized by using the MEMS technique. The vibration scanning frequencies of 4434 Hz and 179 Hz accomplished one and 2D scanning images for optical applications. A vibration angle of 11.2 degrees at a high frequency was achieved in an ambient environment, and the maximal vibration angle was increased by 31% at a vacuum degree of 76 mTorr. In addition, the thermal distribution in the proposed structure was determined by the customized vacuum system. The mirror plate can successfully isolate the thermal source, which is produced by the solenoid coil, even in the high vacuum environment. Moreover, the driven voltage in various waveforms is discussed in this thesis. Experimental results indicate that the sine wave has the largest scanning angle under the same input energy. These results reveal the small size, low weight, and potentially low cost that makes electromagnetic microactuators desirable for several applications of optical systems.
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