Applications of the Fraunhofer-diffraction method for plasma-wave measurements

Abstract

The improved theoretical analysis of Fraunhofer-diffraction method as a new means to measure the frequency, wavenumber, intensity and even spatial position and propagating direction of plasma waves is presented. It is further, experimentally verified and the measuring accuracies are ascertained by measurements in a microwave region, of ion-acoustic waves in a DC discharge. Successes of introducing the practically important conditions into theoretical analysis have made it possible to establish this method as a standard and powerful diagnostic technique for measurements of plasma waves and turbulences in various plasmas such as in Tokamaks.