The time‐average electroluminescent emission intensity, , of powdered phosphors has been measured over wide ranges of the applied sinusoidal voltage, V. The best fit for moderate and high voltages has been obtained with . The emission intensity of all phosphors goes to a finite saturation value if the applied voltage becomes very large. The approach to this saturation is given by . The saturation brightness, A, is in almost all cases proportional to the applied frequency. Since the emission of the particles of a powdered electroluminescent phosphor is in general very nonuniform, the over‐all emission intensity, , must be the inte‐gral over all volume elements, dv, of the local brightnessβ. This integral fits the experimental results if and . It is believed that normally a and 6 are essentially constant in this integral but that the constant of proportionality, c, between the electric field strength, F, and the voltage, V, obeys a certain statistical distribution throughout the phosphor due to the complex geometrical structure of the phosphor.