Abstract

A multichannel interferometer, designed for tokamak plasma-density measurements, is described. The phase shift experienced by the probing beam is transferred to a low-frequency signal obtained by Doppler shifting the frequency of the reference beam. This ensures a sensitivity of 10⁻² fringe. The source is a cw HCN waveguide laser, with a 150-mW-output power. Eight channels are in operation on TFR. The variation of the line density as a function of time for each channel is deduced from the phase shift measurement by an on-line computer.

© 1977 Optical Society of America

Multichannel far-infrared laser interferometer for electron density measurements on the tokamak fusion test reactor

D. K. Mansfield, H. K. Park, L. C. Johnson, H. M. Anderson, R. Chouinard, V. S. Foote, C. H. Ma, and B. J. Clifton
Appl. Opt. 26(20) 4469-4474 (1987)

Evaporographic and pyroelectric image recording for two-dimensional plasma interferometry in the far infrared

G. Dodel and W. Kunz
J. Opt. Soc. Am. 67(7) 975-978 (1977)

Plasma effects in the HCN laser

R. Turner
Appl. Opt. 16(5) 1197-1203 (1977)

Far-Infrared Interferometer for the Measurement of High Electron Densities*

Sanborn C. Brown, G. Bekefi, and R. E. Whitney
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Electron Density Measurement in the HCN Laser Using Faraday Mode Splitting Technique

R. Turner
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