Abstract: A method of making a lanthanum cerium terbium phosphate phosphor involves the coprecipitation of a rare earth nitrate solution with diammonium hydrogen phosphate to form a lanthanmum cerium terbium phosphate, combining the phosphate with a fluxing compound, and firing the resulting mixture to form the phosphor.

Abstract: A method is disclosed for producing a terbium activated cerium magnesium aluminate phosphor which comprises forming a uniform powder blend consisting essentially of in percent by weight from about 73 to about 74 aluminum oxide wherein the aluminum oxide can be alpha aluminum oxide or gamma aluminum oxide or combinations thereof, from about 12 to about 14 cerium oxide, from about 2 to about 3 magnesium, from about 0.3 to about 0.7 fluoride, and from about 6 to about 9 terbium, firing the blend in a non-oxidizing atmosphere at a temperature of from about 1500.degree. C. to about 1800.degree. C. for a sufficient time to produce the phosphor wherein the particle size is no greater than about 5 micrometers in diameter. The phosphor is then cooled and deagglomerated.