Laser induced damage in optical glasses using nanosecond pulses at 1030 nm

The "Bivoj" 10 J, 10 ns, 10 Hz, Yb:YAG (1030 nm) diode-pumped solid state laser (DPSSL) at the HiLASE Centre was used to investigate the laser-induced damage of optical glasses with different refractive index (BK7, SF8, FS, LIBA2000). The samples were polished using a combination of methods and cleaned in ultrasonic bath or with ion beams. Sample surface was characterized using white-light interferometry (WLI) and laser confocal microscopy (LCM). For the laser-induced damage threshold (LIDT), an S-on-1 procedure was selected, the testing taking place in accordance with the ISO 21254 standard Due to the high energy per pulse of the "Bivoj" system we were capable of using beams with more than 500 gm diameter (using a long focusing mirror) and thus, including different surface defect in the LIDT measurement. The damage of the glasses was usually observed on the rear side (ballistic damage) due to constructive interference, however we manage to see on few samples front damage also. Values above 50 J/cm(2) were common for all tested samples.