Predicting plasma properties using power‐controllable fluorescent lamps under electromagnetic wave radiation

Abstract

This research proposed an experimental method to predict plasma properties in fluorescent lamps with the aid of electromagnetic (EM) wave propagation. A set of power-controllable fluorescent lamps are placed between two antennas as a layered plasma medium. The electron density of plasma was adjusted through luminance control of the fluorescent lamps, and the transmission of the EM wave through the area occupied by plasma was achieved. The EM wave reflection and transmission through the plasma area were experimentally measured. By using the time-domain experimental method, and with aid of the Fourier transformation, EM wave changes in the phase and variance in the intensity are tested. The plasma collision frequency and electron density are then mathematically derived based on the EM wave scattering model theory in unmagnetized plasma. This research provides an experimental approach to predict the plasma properties and diagnose the interaction between EM waves and plasma. The proposed experimental method can be implemented with other types of antennas and extended to a wide range of circumstances, such as monitoring the discharge changes in other plasma sources.