High diversity of materials
In contrast, other materials such as wolfram carbide, ceramics or green compacts in which extremly smooth and homogeneouse engravings can produce a readable and detectable label. The labeling ground is flat and even, the inscription is only a few micrometer deep (< 10 micrometers are enough). In the case of plastics, an ultrashort pulse laser marking is also possible. For example for multiple coated or varnished plastics, a contrast is produced by the ablation/ evaporation of the top layers. In case of brighter plastics, the colour of the plastic is modified by a brief melting process and appears dark on the brighter plastic underground. In particular for the medical technology, the labelling of plastics is interesting and important. The smooth plastic surface neither changed in the inscription nor in the surrounding area and germs can still not be attached to the material.