A laser engraving head (6) for use in preparing a medium for a printing process includes a deflector (AOM). The deflector, which may be an acousto-optic modulator, deflects the laser beam which is focused by a lens (L) onto the surface of the medium. The lens (L) may be arranged telecentrically...http://www.google.ca/patents/US5748222?utm_source=gb-gplus-sharePatent US5748222 - Laser angroxing head employing acousto-optic modulator
