Absorption and emission spectra of electroluminescent phosphors, activated by Cu and Pb, are reported. Three absorption bands are observed, at 3.18 electron volts (ev), at about 2.7 ev, and somewhere below one ev. The infrared absorption band is associated with the Pb activator but its exact location is uncertain. The emission spectra of both blue and green phosphors may be resolved into the same emission bands, at 2.15, 2.4, and 2.7 ev, respectively. The primary difference between the spectra of blue phosphors and green phosphors lies in the ratio of the amplitudes of the green and blue bands. This ratio is also shown to be a function of the frequency of the applied alternating field, but is independent of the magnitude of the field.