Raising damage thresholds of gradient-index antireflecting surfaces by pulsed laser irradiation

Abstract

Gradient-index antireflecting surfaces produced by neutral solution processing have a median surface damage threshold of 12 J/cm2 for 1-ns, 1064-nm pulses. We have found that the threshold can be increased to 25 J/cm2 by irradiating the surface with 1064-nm wavelength pulses with fluence below the initial 12-J/cm2 threshold. Damage thresholds, both before and after this treatment, increased as the square root of the pulse duration in the 1–20-ns range.