CW- and Q-switched Lasers

From Continuous-Wave Operation to Pulse Peak Capacity

The laser-active Nd:YAG solid-state rod is activated via laser diodes. In contrast to conventional lamp pumped solid-state lasers, the absorption of diode light in the Nd:YAG-rod is much more efficient. Hence, the beam quality that is based on a low thermal strain as well as on the lens value of the Nd:YAG crystal is improved and provides electric efficiency that is significantly higher.

As a special mode of operation of the continuous-wave or CW-laser the Q-switch is employed. In the process the course of beam in the laser resonator through the laser-active medium is optically blocked by an active element (Q-switch). At the same time the continuously added pump energy is temporarily stored in the Nd:YAG crystal. After the clearance of the interlock respectively after the opening of the optical path, the entire stored energy is released in one very short pulse. Afterwards, the optical path is locked again. This process is repeated continuously with a frequency of basically CW to 100 kHz, whereas the lengths of the pulse can always be varied between 15 and 400 ns. With these short pulses pulse peak performances are generated that can reach with up to 3 MN way beyond 1000 times of CW laser performance.