Automated test station for laser-induced damage threshold measurements according to ISO 21254-1,2,3,4 standards

Abstract

An automated test station to measure the laser-induced damage threshold (LIDT) according to ISO 21254-1,2,3,4:2011 standards is presented. The laser is a single longitudinal mode, 500 mJ, 6 ns, Q-switched, 10 Hz, linearly polarized, 1064 nm laser, with 2-nd and 3-rd harmonic capabilities. The machine is able to operate the S-on-1 test (S = 500), or the Type 2 endurance (durability) test. The main blocks of the station are described, emphasizing some original solutions. Preliminary results of LIDT measurements using the S-on-1 test on several coatings and on uncoated fused silica substrates with various degrees of roughness are also presented.