Laser Damage Resistance of Photo-Thermo-Refractive Glass Bragg Gratings
Abstract
Thick Bragg gratings recorded in the volume of photo-thermo-refractive (PTR) glass have found wide application in high-power laser beam control. They have been successfully used for spectral beam combining, angular magnifying for beam scanning, selection of transverse and longitudinal modes in laser resonators etc. Laser damage was studied in PTR glass blanks and gratings fabricated under different conditions. No threshold reduction was found after grating recording in PTR glass. The laser damage threshold of a volume Bragg grating for a single mode 1 ns pulse at 1054 nm focused on inclusions was 7 J/cm2, while irradiation of inclusion-free sites resulted in surface damage at 20 J/cm2. N-on-1 laser damage tests 1 for 10 Hz repetition rate 1064 nm multimode 8 ns pulses focused to a 78 m diameter spot have shown a 32 J/cm2 threshold for a Pt-melted sample with detected inclusions, and a surface damage threshold greater than 42 J/cm2 for a sample with no detected Pt-inclusions.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jan 01, 2004
- Accession Number
- ADA451832
Entities
People
- Ansgar W. Schmid
- Larissa N. Glebova
- Larry D. Merkle
- Leonid B. Glebov
- Mark Dubinskii
- Semyon Papernov
- Vadim I. Smirnov
Organizations
- United States Army Research Laboratory