Two-photon polymerization is a laser-based 3D printing method that cures a photosensitive resin only where two photons are absorbed at the same time. Because the reaction happens at the laser’s focal point, it can create extremely small features, often at micron or sub-micron scale. That precision makes it useful for micro-optics, sensors, microfluidics, and other components that standard printers cannot build.
In cyber security, the key issue is trust in the fabrication workflow. At this scale, tiny changes in the design file, laser exposure, alignment, or resin chemistry can alter a part in ways that are hard to see without inspection. That matters for secure hardware, research devices, and supply-chain integrity, where a hidden defect or unauthorized modification could change behavior without obvious signs. Defenders therefore rely on strict file control, process validation, and metrology to verify that the printed object matches the intended design.