Plasma diagnostics with lasers

A general description of a laser plasma diagnostic set-up is given. It is explained how the electron density, the electron and ion temperatures and their distributions can be measured by scattering laser light on free and bound electrons as well as on plasma modes. The different types of interferometers used for the measurement of the refraction index of the plasma are described. The Faraday rotation measurements capable of determining the current density and the local magnetic field are briefly mentioned. (P.L.)