Using microstereolithography technology based on dynamic pattern projection, we can fabricate micro parts with high aspect ratio. In this technology, STL file is the standard format as the same of conventional rapid prototyping system, and 3D part is fabricated by stacking layers that are sliced as 2D section from STL file.
In the conventional method, the resin surface is cured as scanning laser beam spot according to the section shape, but in this research, we use projection process which enables to cure the resin surface by one irradiation. DMD is a dynamic pattern generator that makes black and white regions according to bitmap image generated from sliced section.
In this paper, we deal with the operation of dynamic pattern generator, fabrication of microstructures, and curing characteristics. Firstly, we mention microstereolithography apparatus and process including optically designed position and rotation of lenses, mirrors, and DMD according to light path. Secondly, we examine curing characteristics between exposure time and curing depth and width. Thirdly, we consider optimal exposure pattern such as several exposures instead of one exposure with the same exposure time. This enables the part fabricated more accurately because of not excessive but proper energy delivery to the resin surface. Finally we verify this system by fabricating micro part with high aspect ratio and complexity.