The Photonic Professional GT , a 3D printer developed by Nanoscribe, uses two-photon polymerization (2PP), a process in which a laser beam exposes a photosensitive material in order to cure it. Almost any imaginable 3D polymer structures with sub-micron details up to a line width of 200 nm can be achieved using a layer-by-layer process. The technology allows the direct and rapid production of polymer masters from CAD data, which can then be used as a prototype for molding processes such as injection molding or hot stamping.
Micro-optical elements (lenses, prisms or retroreflectors), for example, can be manufactured additively with high dimensional accuracy using this technique. The polymer masters can then be molded into a nickel shim by electroforming. In the process, the 3D-printed polymer structure is sputter-coated with a thin metal layer onto which a nickel shim is electrodeposited.