https://doi.org/10.1140/epjd/e2011-20366-x
Regular Article
Stochastic homogenization of the laser intensity to improve the irradiation uniformity of capsules directly driven by thousands laser beams
1
Universidad Politécnica de Madrid, 28040
Madrid,
Spain
2
CEA, DAM, DIF, 91297, Arpajon, France
a e-mail: mauro.temporal@hotmail.com
Received:
20
June
2011
Received in final form:
5
September
2011
Published online:
22
November
2011
Illumination uniformity of a spherical capsule directly driven by laser beams has been
assessed numerically. Laser facilities characterized by
ND = 12, 20, 24, 32, 48 and 60 directions
of irradiation with associated a single laser beam or a bundle of
NB laser beams have been considered. The
laser beam intensity profile is assumed super-Gaussian and the calculations take into
account beam imperfections as power imbalance and pointing errors. The optimum laser
intensity profile, which minimizes the root-mean-square deviation of the capsule
illumination, depends on the values of the beam imperfections. Assuming that the
NB beams are statistically independents is
found that they provide a stochastic homogenization of the laser intensity associated to
the whole bundle, reducing the errors associated to the whole bundle by the
factor
,
which in turn improves the illumination uniformity of the capsule. Moreover, it is found
that the uniformity of the irradiation is almost the same for all facilities and only
depends on the total number of laser beams Ntot = ND × NB.
© EDP Sciences, Società Italiana di Fisica and Springer-Verlag 2011