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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)

Abstract

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.

Copyright (c) 2012 The Japan Society of Plasma Science and Nuclear Fusion Research

Keywords

Thomson scattering, multi-laser configuration, beam combining

DOI: 10.1585/pfr.7.2402030

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References

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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).