Illumination uniformity of a capsule directly driven by a laser facility with 32 or 48 directions of irradiation

The uniformity of the illumination of a spherical capsule directly driven by laser beams has been assessed numerically. Two schemes characterized by 32 and 48 directions of irradiation with associated a single laser beam or a bundle of laser beams characterized by a super-Gaussian intensity profile are considered. The calculations take into account beam imperfections as power imbalance and pointing errors. It is found that the optimum laser intensity profile, which minimizes the illumination uniformity, depends on the beams’ imperfections. A comparison between both schemes shows that the 48 beams configuration allows better illumination uniformity than the 32 beams’ configuration.

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