Laser-induced damage of overcoated materials at high humidity

Abstract

Exfoliation of optical thin films at high humidity in the air is serious problem. Deterioration of three kind of optical thin films deposited on three types of substrate with different water-resistance (phosphate glass LHG-8, BK-7, and fused silica glass) at high humidity condition was studied. Thin films deposited on fused silica glass with highest waterresistance showed a best result for the exfoliation problem. Silica film seemed to be best for the surface observation at high humidity, but the laser-induced damage threshold(LIDT) was considerably lowered.

Laser-Induced Damage and Environmental Stability of Thin Films Deposited by Ion-Assisted Electron-Beam Deposition

“…Recently, high-power and high-quality lasers have been widely used in material machining and processing, microlithography, precise measurement, and medical science. 1) These lasers are composed of many optical components, whose surfaces are coated with optical thin films. The output energy of a high-power laser is mainly limited by the laser-induced damage of an optical thin film.…”