Résumé

This paper examines the behaviour of EL emissions in a silicone gel material. Due to the challenges in achieving homogeneous field configurations with soft materials, the study was conducted using a needle plane arrangement at various applied voltages up to 10 kV, and a constant frequency of 50 Hz. The voltage dependence of the EL intensity and of EL phase pattern reveal that certainly several mechanisms of light excitation are active. Given the very high field set near the needle tip, discharge as well as material degradation may be at play. Electroluminescence spectra were recorded and compared to photoluminescence and cathode-luminescence spectra. A strong emission band was observed at 590 nm under electron beam irradiation and attributed to material degradation. Also, a weak fluorescence emission was identified. As regards the EL spectrum, it was concluded that discharges are probably the main source of light. Extra work is necessary to exploit EL measurements in silicone gel.