A comparison between CW and pulsed mode operations of light-emitting devices based on alizarin violet

We have fabricated light-emitting devices based on alizarin violet. Transient responses of such devices have been studied by applying a sequence of two square-wave voltage pulses. Concentration of the active material in the emitting layer, and the amplitude of the voltage pulse have been varied to study the affects of space-charges in device operation. The devices have been operated under CW and pulsed modes. Current–voltage and luminance–current characteristics under two such modes have been compared. The rise in device temperature under CW mode has been estimated from the ratio of current densities in the two modes. Higher temperature under CW mode has resulted in lower luminance as compared to pulsed mode. © 2001 Kluwer Academic Publishers