1. Principle of UV laser inner engraving technology
The short wavelength of UV laser (355nm) makes its photon energy as high as 3.5eV, which can directly break the Si-O bond in the glass material (bond energy is about 4.5eV), and form micro-explosion points in the focal area through nonlinear absorption effect. This processing method has the following characteristics:
1. Cold processing mechanism: the heat-affected zone is less than 5μm, avoiding thermal stress cracks of traditional lasers
2. Nonlinear absorption: only works at the focus to ensure clear engraving boundaries
3. Three-dimensional control accuracy: the minimum spot diameter can reach 10μm, supporting 0.01mm layer thickness control
II. Application scenario breakthrough
1. Ultra-thin glass engraving: invisible QR code engraving with a transmittance of 99% on 0.1mm thick flexible glass
2. Optical device processing: used for the production of internal gratings of AR glass waveguides, with a line width accuracy of ±0.8μm
3. Anti-counterfeiting and traceability field: engraving three-dimensional microstructures on the bottom of wine bottles, requiring a 5000DPI microscope to read
4. Medical device marking: meet ISO 13485 standards, engrave permanent scales on the inner wall of the test tube
Operation suggestions:
1. When using a 50mm focal length field lens, the depth of focus is controlled at ±0.2mm
2. The engraving speed is recommended to be set to 800-1500mm/s, and adjusted according to the complexity of the pattern
3. Regularly replace the UV laser window mirror (recommended 2000 hours/time)
