Alternating current thin film electroluminescent device having blue light emitting alkaline earth phosphor

A light emitting phosphor having improved luminance is incorporated into an ACTFEL device having front and rear electrode sets, a pair of insulators sandwiched between the front and rear electrode sets, and a thin film electroluminescent laminar stack which includes a phosphor layer having the formula MIIS:D,H,F where MII is taken from the group calcium, strontium, barium, and magnesium, S=sulfur, D is taken from the group copper, lead, gold, silver, magnesium, antimony, bismuth and arsenic, H is taken from the group fluorine, chlorine, bromine, and iodine, and F is taken from the group gallium, indium, aluminum, germanium, silicon, lanthanum, scandium, and yttrium. Deep blue and green chromaticity phosphors may be obtained through selection of multiple co-dopants and adjusting their relative concentrations.