Material Processing

Enhancing precision in engraving systems: the role of ultra short pulse lasers and AO devices

The use of ultra short pulse lasers whose duration is in the picoseconds or even femtosecond range, is quite common in engraving systems. Since the duration of the energy is also short, this limits the among of heat on the workpiece and hence perform precise removal of the extra material (fig.12.). AO devices are widely used here as pulse pickers. In fact, they are introduced into the high repetition rate laser systems in order to extract a single or several pulses to have a control on the average optical power and hence ensuring a precise control on the energy delivered to the workpiece.

Optimizing material processing: the power of q-switched lasers and ao devices

Q-switched lasers are also involved in material processing due to their ability of delivering high peak power pulsed lasers.They are usually nanosecond pulses and these can be produced by introducing an AO Q-Switch inside the laser cavity: when the AO device is ON, it introduces losses inside the laser cavity by diffracting the light out of the cavity and hence suppressing the lasing effect. There is then an accumulation of energy inside the cavity and when the AO device (no diffraction) is OFF, a high intense laser pulse is generated