On the excitation efficiency in ZnS:Mn thin-film electroluminescent devices

The direct measurement of dependence of excitation efficiency (eta sub exc) on applied voltage showed an increase in eta (sub exc) with increasing excitation level and its non-dependence on applied voltage for optimized devices used in industrial production. The decrease in total deficiency of eta at high excitation levels is partly due to a decrease in eta (sub x) and not entirely to radiative efficiency.