An open source three-mirror laser scanning holographic two-photon lithography system.

Two-photon polymerization (TPP) is a leading technique for fabricating 2D and 3D nanostructures with sub-diffraction-limit features. This study introduces an open-hardware, open-software holographic multibeam TPP system featuring a phase-only spatial light modulator (SLM) and a three-mirror scan head. The novel three-reflective surface design—with two mirrors scanning along the same axis—resolves virtual conjugation loss in large galvanometric mirrors, effectively doubling the writing field of view from ~200μm to ~400μm.

With a voxel resolution of ~250nm × ~1050nm (lateral × axial) and a writing speed of 2000 voxels/s across three simultaneous beams, this system significantly enhances high-speed, large-area micro and nanofabrication. The combination of holographic beam shaping and optimized scanning ensures precise and scalable multi-beam lithography, making it an advanced tool for nanotechnology, micro-optics, and biomedical engineering.

Keywords: two-photon polymerization, holographic lithography, spatial light modulator, multi-beam fabrication, nanostructures, sub-diffraction-limit, high-resolution 3D printing, microfabrication, advanced lithography, nano-optics.