In recent years, the method of incoherent Thomson scattering has been applied to make measurements of electron properties of glow discharges used for industrial applications. These plasmas have electron density of the order of 10 17 m −3 and electron temperature of a few eV. This paper reviews the recent progress in this research area. Details of the experimental systems are given and examples of measurements made in several different types of glow discharges are presented. A method in which Thomson scattering is combined with Rayleigh scattering to provide direct measurements of the neutral density is also described and an example of measurements is given. The electron velocity and energy distribution functions are also an important property of these plasmas, and the extent to which Thomson scattering can measure the distribution function is discussed. Future trends for Thomson scattering in glow discharges are also discussed.

In order to understand particle transport systematically in toroidal plasmas, electron density profiles were compared in JT-60U tokamak and LHD helical plasmas with low collisionality. The peakedness of density profiles increased with decreasing collisionality in ELMy H-mode plasmas of JT-60U when the collisionality at half the minor radius was in the collisionless regime. The collisionality dependence of density profiles in LHD plasmas was similar to that in JT-60U plasmas in the same collisionality regime when neoclassical transport was reduced by geometrical optimization. On the other hand, in LHD plasmas having relatively larger neoclassical transport than that in the above case, the peakedness of the density profiles decreased with decreasing collisionality. Density profiles in LHD plasmas tend to approach those in JT-60U, which are dominated by anomalous transport, as the contribution of neoclassical transport was reduced.

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Spatial distributions of electron density (ne) and electron temperature (Te) of a micro-discharge plasma for an alternating current plasma display panel cell were directly measured using the laser Thomson scattering method. The use of a triple-grating spectrometer was very successful in suppressing the strong stray laser light and allowed us to perform measurements at 0.1 mm above the surface of the electrode substrate. Values of ne and Te were (0.2–3)×1019 m−3 and (1.6–3.4) eV, respectively, depending on the time from the beginning of the pulsed discharge and the observation position. The structure of the micro-discharge is discussed in terms of the obtained distributions of ne and Te.