The understanding of the different types of lasers and their wavelengths makes it possible to mark a variety of materials. However, unless the optimum laser marker is selected for the material to be marked, it will not be possible to achieve the desired finish. This section presents how to select the optimal laser marker for glass, paper, ceramics, PCBs and other materials.
A marking is achieved by generating tiny cracks in the glass. A repeated marking at a lower power allows a clearer marking.
The CO2 laser markers that perform the marking by applying heat to the object are optimal. High power marking can sometimes cause large cracks, so it is more effective to make multiple passes with low power marking. The blur allows the adjustment of the thickness of the lines.
Thermal marking melts the glass surface. Because the quartz glass is heat resistant, laser marking is possible without cracking.
High visibility marking is achieved by burning the printed surface (solid coating) with the laser. The high contrast result allows highly readable barcodes and other detailed markings.
Marked on unprinted white paper
The marking is achieved using a high power laser that burns the white surface of the object. When moving from the stamping or other methods to the laser, it is not necessary to change the designs of the cartons or other products, which guarantees a smooth update.
The CO2 laser markers that perform the marking by applying heat to the object are optimal. Soot and similar things can also be generated during marking, so a dust collector may be necessary in addition to the laser marker.
In zirconia ceramics, the marking looks black as if the surface had been burned. In alumina ceramics, the marking looks as if the surface had melted.
Printed circuit boards
White marking is done by engraving only the surface of the welding mask. The surface engraving allows a clear marking without exposing the pattern.
The marking must be done at low power, since if the marking power is too high, soot will be generated on the PCB. In addition, as the standard wavelength laser passes through welding masks, which would entail the risk of damaging the pattern, the best lasers are CO2.