Two-photon polymerization (2PP) is a "nano-optics" 3D printing method similar to photocuring rapid prototyping, and futurist Christopher Barnatt said the technology could become the mainstream form of 3D printing in the future. Internationally, scientists at Vienna University of Technology are united in their efforts to improve the performance and imaging technology of photosensitive resins. The Imperial College also printed a 100-meter-long model of the Great Wall of China presented to President Xi via Germany's Nanoscribe equipment. Source: Great Wall model printed by NanoScribe device The potential scope of application and impact of two-photon polymerization technologies such as NanoScribe is very special. Its application areas include: Photonics: Photonic Crystals, Metamaterials, DFB Lasers Photon Resonance Rings, Diffraction Optics Micro Optics: Micro-Optics, Integrated Optics Micro Fluidics: Biomedical Chip Systems, Materials Research and Development and Analysis, 3D Infrastructures and Microfluidic Pathways Life Sciences: Extracellular Array Structures, Stem Cell Isolation, Cell Growth Studies, Cell Migration Studies, Tissue Engineering Nano- and Microtechnology: Ultra-fine Resolution Optical Mask, Gecko and Lotus Effect Analysis The principle of two-photon polymerization is to selectively cure the photo-sensitive resin by using "femtosecond pulsed lasers". Sounds almost like light-cure rapid prototyping, with the difference that the minimum layer thickness and XY-axis resolution achievable with two-photon polymerization are between 100 nanometers and 200 nanometers. In other words, 2PP 3D printing technology is several hundred times more accurate than traditional photocurable molding technology and prints less than bacteria. Mirror movement is a core of 2PP technology. The laser guided through the mirror must be very precise, and the mirror is constantly moving during the printing process, so the movement frequency must be adjusted very accurately.