Power voltage source synchronized with a spectrometer for real-time spectroscopic studies of pulsed discharges

The evolution of the species generated in a plasma may be characterized thr ough real-time optical emission spectroscopy. Nevertheless, for experimenta l situations in which the light emission intensity is insufficient for acqu isition times of several tens of milliseconds (typical resolution time of o ptical multichannel analyzers), some complementary instrumentation has to b e incorporated, In this paper, we present the design of an experiment to st udy the spectroscopic evolution of a plasma during a switch-on of a de disc harge, and/or during its switch-off (afterglow), The solution consisted of a periodic discharge generated by a de square wave voltage source, synchron ized with the optical multichannel analyzer of the spectrometer through its TTL (logic family of Transistor-Transistor Logic) level pulse. The periodi city of the discharge under similar physical conditions allows accumulation the spectroscopic information for each cycle, making possible a time resol ution of tens of milliseconds by increasing the resulting intensity profile of the spectra.