This discussion provides a good understanding of the difference between Radio Frequency Discharge (RFD) and Dielectric Barrier Discharge (DBD) in an excimer lamp. Qualitatively speaking, micro-plasmas are formed in a DBD (which are thread-like in structure). These thread-like plasmas generate irregular light emission (flickering light). In the case of a RF discharge, a plasma is formed uniformly between the dielectric material, resulting in a very uniform emission of light (spatially and temporarily), i.e., no flickering light.