Diagnostic Techniques Introduction

 Diagnostic Techniques

In the diagnostic techniques that we use, two different classes can be distinguished: passive techniques (spectroscopy) and active ones. In the former case, the radiation from the plasma is studied. This is a very old technique, and technically relatively simple. Interpretation of the results, however, can be complicated. In the latter case, some interaction with the plasma takes place, for example, a laser beam is pointed at the plasma. This can offer much more direct information about the plasma, but is more demanding on the experimental setup. A short introduction to a number of diagnostic techniques that are used in the polydiagnostic lab is given below.

Schematical layout and overview of the diagnostic tools in the polydiagnostic laboratory

Active Diagnostic Techniques

• Thomson, Rayleigh and Raman Scattering

• Diode Laser Absorption

• (Ta)LIF

Passive Diagnostic Techniques

• Absolute intensities of spectral lines

• Spectral Line Broadening

• Continuum radiation

• Power Interruption