Portal de Periódicos da CAPES

Programmable beam spatial shaping system for the National Ignition Facility

2011; SPIE; Linguagem: Inglês

10.1117/12.875794

1996-756X

John E. Heebner, M. Borden, Phil Miller, Steve L. Hunter, Kim Christensen, M. J. B. Scanlan, C. Haynam, Paul J. Wegner, M. R. Hermann, G. Brunton, Eddy Tse, Abdul Ahad S. Awwal, Nan Wong, Lynn G. Seppala, Mark Franks, E. V. Marley, K. Williams, T. Budge, Mark A. Henesian, Christopher J. Stolz, Tayyab Suratwala, Marcus V. Monticelli, D. Walmer, S. N. Dixit, C. Widmayer, Justin Wolfe, J. Bude, Kelly McCarty, Jean-Michel Di-Nicola,

Laser-induced spectroscopy and plasma

A system of customized spatial light modulators has been installed onto the front end of the laser system at the National Ignition Facility (NIF). The devices are capable of shaping the beam profile at a low-fluence relay plane upstream of the amplifier chain. Their primary function is to introduce "blocker" obscurations at programmed locations within the beam profile. These obscurations are positioned to shadow small, isolated flaws on downstream optical components that might otherwise limit the system operating energy. The modulators were designed to enable a drop-in retrofit of each of the 48 existing Pre Amplifier Modules (PAMs) without compromising their original performance specifications. This was accomplished by use of transmissive Optically Addressable Light Valves (OALV) based on a Bismuth Silicon Oxide photoconductive layer in series with a twisted nematic liquid crystal (LC) layer. These Programmable Spatial Shaper packages in combination with a flaw inspection system and optic registration strategy have provided a robust approach for extending the operational lifetime of high fluence laser optics on NIF.