Optical Review

, Volume 7, Issue 3, pp 216–220

Two-Dimensional Multi-Lens Array with Circular Aperture Spherical Lens for Flat-Top Irradiation of Inertial Confinement Fusion Target

  • Noriaki Nishi
  • Takahisa Jitsuno
  • Koji Tsubakimoto
  • Shinichi Matsuoka
  • Noriaki Miyanaga
  • Masahiro Nakatsuka
LASERS

DOI: 10.1007/s10043-000-0216-5

Cite this article as:
Nishi, N., Jitsuno, T., Tsubakimoto, K. et al. OPT REV (2000) 7: 216. doi:10.1007/s10043-000-0216-5

Abstract

A two-dimensional multi-lens array 350 mm in diameter with spherical element lenses has been tested to improve the irradiation uniformity of a high power glass laser for inertial confinement fusion (ICF). A circular shape for the element lens aperture is chosen to eliminate azimuthally asymmetric intensity distribution. An approximate flat-top intensity distribution is obtained with a lens array of 37 lenses. Beam patterns of a coherent laser and partially coherent light (PCL) with the random phase plate (RPP) and the multi-lens array (MLA) are measured in a GEKKO XII glass laser system. Spherical mode structure of the irradiation nonuniformity of 5.6% with MLA is estimated with cos3 θ distribution of absorption coefficient in the target plasma.

Key words

multi-lens arraycircular apertureirradiation nonuniformitylow-modeflat-top

Copyright information

© The Optical Society of Japan 2000

Authors and Affiliations

  • Noriaki Nishi
    • 1
    • 2
  • Takahisa Jitsuno
    • 1
  • Koji Tsubakimoto
    • 1
  • Shinichi Matsuoka
    • 1
  • Noriaki Miyanaga
    • 1
  • Masahiro Nakatsuka
    • 1
  1. 1.Institute of Laser Engineering, Osaka UniversityOsakaJapan
  2. 2.Usho Optical Systems Co., Ltd.OsakaJapan