Digital Micro-mirror Array-based Imaging Systems, High-speed Scanning

DMD (Digital Micro-mirror Device) is a device which has hundreds of thousands of high-speed micro-mirrors in one chip. The number of the high-speed micro-mirror means the resolution ratio. Compare to TFT-LCD, DMD has a high reflectivity and contrast. The object is imaged on DMD,and then use the pixel level and high flip frequency of the device,scanning the image to the detector which has a high sensitivity to Visible light. That means the scanning of the object without optical source's illuminate on daytime is possible.It can also be used with a optical source.The first part of this paper introduces the spatial light modulator. It particular compare the more common now TFT-LCD (transmission-type) to DMD (reflection-type) and give this two kinds of spatial light modulators'advantages and disadvantages. The high speed optical system based on DMD is given.The second part is the whole system design, including the optics, electricity design. Because of the system has two process of imaging,(first from object to DMD,and then from DMD to detector),the paper emphasize the mentality of the optical desire. Use of optical design manual and optical design software to optimize system parameters.The third part is given the software which contral the DMD hardware, at the same time use VC++ to development of control program based on DMD library function.The forth part is on the system test, analysis of experimental data, in order to compare reflex spatial light modulator to the transmission one.Finally, the research work is summarized. The advantage and the disadvantage of the system, and the direction of scanning optical system of subsequent research is given.