TresClean Partner USTUTT Achieves Major Project Goals
The TresClean project has recently achieved two major goals. Firstly, in successfully implementing high-power think-disk multipass amplifier (TD-MPA) delivering stable 1 kW of average output power at a repetition rate of 300 kHz and a pulse duration below 7 ps. Secondly, in demonstrating the generation of high average power Green and UV radiations by second and third harmonic non-linear processes using LBO crystals.
Within the TresClean project, a 1kW thin-disk multipass amplifier delivering up to 1kW of average output power at a repetition rate of 300kW and pulse duration below of 6.7 ps was implemented. With the thermal stabilization measures (by proper choices of the opto-mechanical components of the systems) the beam quality factor as well as the long term stability of the system was drastically improved in comparison to that of the laser system before its upgrade.
The project objectives of 500W green and 100W UV radiations were also successfully achieved and even exceeded by 28% and 37% respectively. The original set goals were 500W at 515 nm (green) at an efficiency >= 60% and 100W at 343 nm (UV) at an efficiency >= 25%. In fact up to 640W of average output power for the SHG could be demonstrated at an excellent efficiency of 70% and beam quality below 1.2 in both axis. 264W of output power was achieved at the cost of beam quality degradadtion. However, at 137W of UV output power the beam quality was measured to be below 1.4 in both axis. With these results all objectives of the non-linear conversion stages were fulfilled.