Fabrication of 3-Dimensional Microstructures Using Dynamic Image Projection

Abstract

As demand for complex precision parts increase, the existing fabrication methods such as MEMS, and LIGA technology have technical limitations with regard to high precision, high aspect ratio, and high complexity. A microstereolithography technology based on DMDTM(Digital Micromirror Device) can meet these demands. DMD enables a system to handle dynamic patterns. In this technology, the same standard format of the conventional rapid prototyping system, the STL file, is used, and 3D parts are fabricated by stacking layers that are sliced as 2D section from STL file. Whereas in conventional methods, the resin surface is cured by scanning laser beam spot according to the section shape, but in this research, we used an integral process which enabled the resin surface to be cured by one irradiation. In this paper, we dealt with the dynamic pattern generation and DMD operation to fabricate microstructures. Firstly, the microstereolithography apparatus and process were discussed. Secondly, the DMD operation according to mirror tilting, and optimal mounters for DMD and reflecting mirror according to light path were described. And thirdly, complex 3D microstructures were demonstrated.