Experimenting with spatial and temporal profiles for the YAG laser damage threshold

Since the value and the shape of the pulse widths and also the spatial profile vary from one test bench to another, it appears interesting to see how the damage threshold evolves with these two parameters. The scaling laws have 2 main impacts: the possibility to compare easily the results between the laboratories and to help the understanding of the damage phenomena. But it can be also a great help on the laser damage threshold specifications of the optical components. Moreover, the spatial law versus the component area could become a request in the future specifications. The first part of this paper is devoted to experimental damage result performed with YAG laser at 1.064 micrometers in R- on-1 mode and in raster scan. 2 pulse widths close to a Gaussian profile is used: around 3 ns and 12.5 ns. Furthermore, 3 laser spot sizes with a shape close to a Gaussian beam are used. Their impact on the laser damage threshold is studied. The results are analyzed with the purpose of finding a tool to extrapolate the result at larger components. To test full large optics is time consuming. A primary automatic test is suggested too quickly eliminate the components below the specifications.