Metalens array boosts two-photon lithography throughput by 1,000×

Researchers at Lawrence Livermore and collaborators demonstrated a metalens-array approach that massively parallelizes two-photon lithography (TPL), replacing a single tightly focused beam with an array of individually addressed focal spots. The team generated more than 120,000 simultaneous foci across a roughly 12 cm² write field, enabling parallel nanoscale polymerization and reporting an effective speed increase on the order of 1,000× compared with conventional single-spot TPL while maintaining nanoscale feature sizes.

The core innovation is the metalens itself: a flat, nanostructured optical layer that shapes phase and amplitude at subwavelength scales. By engineering arrays of these elements, the group can control many focal spots and wavelengths at once, effectively turning a serial nanoscale writer into a massively parallel one. Visual examples from the work show many tiny features printed in parallel — the team even demonstrated multiple minuscule chessboard-like structures produced simultaneously — illustrating the method’s ability to populate arrays of micro- and nanoscale parts in one pass.

That combination of resolution and parallelism addresses a long-standing pain point in 3D printing: two-photon lithography excels at submicron detail but is slow for anything larger than microscopic islands. By extending the usable write field to the centimeter scale while keeping nanoscale resolution, the metalens-array approach could make it feasible to produce high-resolution arrays, microoptics, and patterned surfaces at sizes that were previously impractical for TPL.

Important caveats remain. Optical throughput must scale up to maintain energy per focus when more spots are added, and resin chemistry will need tuning for simultaneous multi-spot curing dynamics. Stitching and edge bonding remain issues if users try to cover areas larger than the current write field, and the overall optical and control system complexity is nontrivial. Commercialization will hinge on solving these engineering challenges and on packaging the approach into systems usable outside specialized labs.

For the community this is a promising direction rather than an off-the-shelf solution. If your work depends on producing many identical nanoscale features or dense arrays, follow developments closely; metalens-based TPL could cut turnaround times dramatically. For makers focused on larger freeform parts, this is less immediately useful until stitching and throughput scale up.

Our two cents? Track metalens TPL for batch nanoscale jobs, verify resin and optical compatibility before investing, and expect early commercial offerings to target labs and small production lines first. This is one to bookmark if you crave nanoscale detail without endless single-beam print times.