Electroluminescence of low density polyethylene under uniform ac electrical field

Electroluminescence (EL) from low density polyethylene (LDPE) under ac stress has been measured using a charge-coupled device (CCD) camera. The temporal, spectral, spatial and phase angle relationships have been determined. The effect of electrode thickness has been investigated and thicker electrodes were found to provide higher EL inception voltages. Images of stressed samples show homogenous distribution of the measured light. The EL intensity was measured as a function of the phase angle of the applied ac stress. Results indicate that the peak EL intensity occurs in advance of the applied stressing voltage with more light emitted at the negative than the positive half cycle of ac voltage.