Laser marking of materials by means of micro mirror array

Increasing the marking speed is of growing importance for the packaging industry. For this reason it was necessary to investigate the potential of micro mirror devices (MMDs) in combination with well absorbed and short-pulsed UV-excimer laser beams. The advantage of this new marking technique in comparison with conventional processes is the ability to generate the finest markings by one laser pulse so the marking speed is only limited by the pulse frequency of the laser. Computer-controlled micro mirror arrays bring highest flexibility into the marking process: within only one laser pulse (typical 30 ... 40 ns), up to millions of pixels can be transferred to the material.