High-Throughput Two-Photon 3D Printing Enabled by Holographic Multi-Foci High-Speed Scanning

Abstract

The emerging two-photon polymerization (TPP) technique enables high-resolution printing of complex 3D structures, revolutionizing micro/nano additive manufacturing. Various fast scanning and parallel processing strategies have been proposed to promote its efficiency. However, obtaining large numbers of uniform focal spots for parallel high-speed scanning remains challenging, which hampers the realization of higher throughput. We report a TPP printing platform that combines galvanometric mirrors and liquid crystal on silicon spatial light modulator (LCoS-SLM). By setting the target light field at LCoS-SLM's diffraction center, sufficient energy is acquired to support simultaneous polymerization of over 400 foci. With fast scanning, the maximum printing speed achieves 1.49 × 10 8 voxels s −1 , surpassing the existing scanning-based TPP methods while maintaining high printing resolution and flexibility. To demonstrate the processing capability, functional 3D microstructure arrays are rapidly fabricated and applied in micro-optics and micro-object manipulation. Our method may expand the prospects of TPP in large-scale micro/nanomanufacturing.

Advancing Tissue Culture with Light-Driven 3D-Printed Microfluidic Devices

“…UV overexposure can cause channel blockages while inadequate curing time causes the leakage of photoinitiators and unreacted monomers. Unlike traditional SLA, TPP uses femtosecond laser pulses to initiate polymerization at the focal point, allowing for voxel-by-voxel construction of 3D structures at a sub-micron scale [ 96 ]. This process enables the creation of complex geometries with smooth surfaces and high aspect ratios below 100 nm precision, which are essential for precise microfluidic applications [ 97 ].…”

Recent advances of biocompatible optical nanobiosensors in liquid biopsy: towards early non-invasive diagnosis

“…46 These fluorescence-based optical nanosensor approaches exhibit a lower LOD for exosomes compared with most conventional ELISA, which demonstrates good potential for exosome identification. Integrating these optical nanosensors into microfluidic devices with complex nanostructures remains a challenge in terms of the cost, complexity, and time-consuming nature of current 3D micro/nanofabrication techniques, such as proximity-field nanopatterning, 47 multi-beam holographic lithography, 48 and femtosecond laser printing. 49 Reducing the cost of microdevice manufacturing and optimizing the selection of microdevice materials are of great significance for improving the interaction efficiency between device interfaces and nanoscale probe materials.…”