A new facility has been designed to enhance laser damage resistance at 351 nm of large scale 3w KDP and silica optics by laser treatment. This facility is a prototype, and the process will be industrialized as a means of fabrication of the LMJ optics. The first step of the process is a conditioning/initiation step, which consists of a UV laser raster scan of the whole optics; the second step is a step of detection and analysis of damage possibly initiated during the previous step; the third step is a mitigation step, which consists of a local melting of the detected damage on silica surface, in order to stop their growth. The facility is equipped with a 3w Nd:YAG laser allowing the process of both KDP and silica. A CO2 laser is used for damage mitigation. Both the lifetime increase and the reduction of the process duration of large scale optics have been taken into account with a view to industrialize the process.