Analysis of 1ω bulk laser damage in KDP

The influence of laser parameters on laser-induced damage in the bulk of KDP is difficult to determine because the damage manifests as discrete sites a few micrometers in diameter distributed throughout a relatively large volume of material. Here, we present a method to directly measure the size and location of many thousands of such sites and correlate them to the laser conditions that produced them. This technique is used to characterize the effects of pulse duration on damage initiated by 1053 nm light in the bulk of KDP crystals. We find that the density of damage sites produced by 1053 nm light is less sensitive to pulse duration than was previously reported for 526 nm and 351 nm light. In addition, the effect of pulse duration on the size of the damage sites produced appears insensitive to wavelength.