[Table of Contents]

Plasma and Fusion Research

Volume 7, 2402030 (2012)

Regular Articles

Coaxial Multiple Laser Beam Combiner for the LHD Thomson Scattering System
Ryo YASUHARA, Ichihiro YAMADA, Kazumichi NARIHARA, Hisamichi FUNABA and Hiroshi HAYASHI
National Institute for Fusion Science, Toki, Gifu 509-5292, Japan
(Received 9 December 2011 / Accepted 3 March 2012 / Published 10 May 2012)


We developed a polarization-based beam-combining method for multiple lasers to improve the time resolution and accuracy of a large helical device (LHD) Thomson scattering system. We combined two or more beams from different apertures of the laser heads in series into a coaxial beam line with the use of polarization optics. We have implemented this beam-combining method in an LHD Thomson scattering system from the 15th experimental campaign. We also propose a method of combining three or more laser beams by the use of a Pockels cell.


Thomson scattering, multi-laser configuration, beam combining

DOI: 10.1585/pfr.7.2402030


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This paper may be cited as follows:

Ryo YASUHARA, Ichihiro YAMADA, Kazumichi NARIHARA, Hisamichi FUNABA and Hiroshi HAYASHI, Plasma Fusion Res. 7, 2402030 (2012).