Laser megajoule 1.06-μm mirror production with very high laser damage threshold

Abstract

As part ofthe LMJ (Laser Megajoule) program, CEA is building the LIL laser with full size optics and LMJ requirements. SAGEM has been selected as the supplier of large optical components and coatings with very high laser-induced damage threshold. Including spare parts, about 100 mirrors 610*430 mm2 with LIDT-3ns > 25 J/cm2 have to be produced. Using a 5 m3 vacuum chamber and the << 100 J/cm2 >> mirror coating process developed at CEA-LETI, with Hafnium and Si02 materials, we are now typically in a serial production phase. To date, about thirty mirrors have been delivered. This paper focuses on the acceptance tests performed after coating, at Sagem then CEA:. LIDT measurement and Raster-Scan on samples . Reflectance mapping on CEA automatic photometer . Reflected wavefront deformation with 0 800 mm /1o CEA interferometer

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Plasma-ion-assisted coatings for 15 femtosecond laser systems

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