LASER-BEAM WORKING DEVICE COMPRISING MEANS FOR FORMING AN IMAGE OF THE REFLECTED ANNULAR LASER RADIATION ON A SENSOR UNIT AND METHOD FOR ADJUSTING THE FOCAL POSITION

摘要

A laser beam processing device has at least one laser beam source (2) for focusing on at least one work piece (12) with a ring-shaped laser focus (26). A device (29) for imaging the laser radiation reflected by the workpiece (12,25) on a sensor unit (24) is provided. An independent claim is included for a method for adjusting the focal position of an annular laser focus.