https://doi.org/10.1051/epjconf/202125503009
SSD detection on LIDT tested coated Fused Silica samples
1 OST Eastern Switzerland University of Applied Sciences, Institute for Microtechnology and Photonics, 9471 Buchs, Switzerland
2 RhySearch, Optical Coating Division, 9471 Buchs, Switzerland
* Corresponding author: heidi.cattaneo@ost.ch
Published online: 18 November 2021
Material changes and Sub-Surface Damage (SSD) under Laser Induced Damage Threshold (LIDT) testing sites were investigated on 3 diverse single layer coated transparent fused silica samples to obtain additional information on damage precursors on these samples. As a detection method, photothermal deflection technique utilizing a resonant UV laser beam was used. The local variations in UV absorption and probe beam transmittance due to previous exposure to high fluence laser pulses were strongly dependent on the coating itself and on the laser energy used during the LIDT testing. Also the obtained LIDT values differ from coating to coating. Detected effects on the coatings and substrate surface beneath ranged from small surface dislocations to complete coating damage with material transformations. Additional absorbing damage precursors were found close to the damaged sites.
© The Authors, published by EDP Sciences, 2021
This is an Open Access article distributed under the terms of the Creative Commons Attribution License 4.0, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
