Multiphoton lithography (MPL) or multiphoton processing is an umbrella term for 3D printing methods relying on photochemical reactions triggered by multiphoton absorption (MPA). The most popular approach is the two-photon polymerization (2PP), also sometimes referred to as two-photon-absorbed photopolymerization, two-photon induced polymerization, two-photon lithography, two-photon laser scanning lithography, multiphoton-excited microfabrication, 3D multiphoton lithography, 3D laser … Continue reading Castle on a pencil tip via nano-scale 3D-printing