Mammoth Stereolithography Video from Materialise

The technology

Starting from a 3D image, a part is built slice by slice from bottom to top, in a vessel of liquid polymer that hardens when struck by a laser beam.
Schematic overview of the stereolithography process

Starting from your STL file, the required supports for overhangs and cavities are automatically generated in the model under construction. The support and model files are then "cut" into thin horizontal slices and programmed into the stereolithography machine.

This machine then uses a computer controlled laser to draw the bottom cross section onto the surface of a liquid polymer that hardens where struck by the laser. The part is then lowered to a depth corresponding to the section's thickness and the next cross section is then drawn directly on top of the previous one. This is repeated until the part is finished.