Part of the umbrella term Rapid prototyping was invented by Chuck Hull and is the oldest patented additive manufacturing process.

In this case, the workpiece is built up layer by layer by (raster) points that materialize freely in space.

The production of these parts, whereby a simultaneous multiple production is possible, takes place from directly on the computer created CAD data.

Additional references:
Rapid prototyping (RP)
Selective Laser Sintering (LS)
Printing process (3D)
Electron beam melting


  • Fig 1: Principle of stereolithography, Source: