Laser marking techniques

In mask marking a mask is used to project an image upon the working surface. A single laser pulse is sufficient for the image to be marked in the plastic. The information content is limited to a surface of approximately 10*30 mm and the masks can be expensive, especially when complex figures are to be marked. This technique offers the highest production rate but is not so flexible.

The highest flexibility is obtained by the use of galvanic mirrors for laser marking. Here the marking is performed by beam manipulation. The laser beam is focused through two computer-controllable mirrors (the galvanic system) and is then used effectively as a pen. In this way very fine patterns of high image quality (even photo quality, more than 600 dpi) can be marked as is schemtically shown in the picture. In using this technique there is obviously some loss in production rate.