Toshiki Niino

Raster‐based exposure through multiple parallel beams in stereolithography

A method to control raster‐based exposure in multiple‐LED photographic curing (MPC) is introduced. During the build process, beams of multiple sources, each exposing a separate area, are projected vertically onto the resin surface while the projector moves continuously across the resin vat. In the projector, 1,024 beams of light are arranged in an array of eight staggered rows. Part‐building data are written in numerical control (NC) geometric details (G)‐codes to produce a physical replica of the digital part design. The sliced 3D data are converted into bitmap data, an image consisting of tiny dots called pixels. The individual layers of a part are built up through pixels arranged in a bitmap. The formation of objects happens through curing in an orthogonal raster with a mesh of 62.5mm. To obtain even intensity in the surface, five beams are used to cure a single string. In part‐building experiments, microscopic photographs taken of parts clarified the characteristic pattern of the exposure technique.