Safety grounding approach for the NIF power conditioning system

Abstract

Results will be presented from an investigation into the effects of substrate reflectivity on the optical emission of a pulsed planar surface discharge, used for dye laser pumping. A OSQ, 1 . 2 5~~ pulse length, lumped element PFN was used to drive a surface discharge over a 3mm thick quartz substrate in the presence of a noble gas. In order to separate reflectivity effects from charge carrier induced optical emission; reflective sheets were inserted between the quartz substrate and the underlying earth return. This allowed electrical discharge interactions with the quartz substrate and cover gas, but not with the reflective backing sheet. Sheets with various reflectivity values were utilised in order to assess the effect of the substrate reflectivity on optical emission of a surface discharge. The second part of this paper will describe the development and characterisation of a surface discharge pumped dye laser. The laser was based on a surface discharge pumped dye laser previously constructed by DERA. This laser utilised a resonant discharge circuit to drive a surface discharge over a PTFE substrate in the presence of a Xe/SF6 cover gas. A quartz Bethune laser dye cell was used to transfer light from the discharge to a Rhodamine 6G laser dye solution. The current laser was designed to demonstrate the energy scaling of laser emission and the enhancement of overall laser efficiency. In order to achieve this, the OSQ, lumped element PFN was used to drive the surface discharge. The surface discharge geometry and discharge materials were modified in order to enhance the laser efficiency and to withstand higher energies. The Bethune cell laser head was retained because it has demonstrated efficient light transfer from a planar emission source-to a laser dye gain medium.References: