Abstract

Over the past few years, optical smoothing of the laser irradiance on targets for inertial confinement fusion (ICF) has been given increasing attention.^1–3 Wavefront aberrations in high power laser systems for ICF produce nonuniformities in tire energy distribution of the focal spot that can significantly degrade the coupling of energy into fusion targets, driving various hydrodynamic and plasma instabilities. The introduction of temporal and spatial incoherence over the face of the beam using smoothing by spectral dispersion (SSD) reduces these irradiance variations when averaged over a finite time interval.^2,3 This paper describes recent experiments on Nova that demonstrate our ability to generate significant bandwidth (>50 cm⁻¹) and smoothing at 351 nm with a statistical bandwidth source. These results are compared with smoothing obtained on Nova using an RF-modulated bandwidth source.

© 1993 Optical Society of America