Cathodoluminescent white phosphors optimization for lighting applications

In recent years, a significant progress has been reported in the area of field emission cathodes and cathode materials for cathodoluminescent vacuum light sources. In this research, we investigated mixes of individual industrially available red, green and blue phosphors in an attempt to create a thermally stable and energy efficient phosphor mixes capable of operating for prolonged time in the conditions of the vacuum field emission light sources. Two mixtures of NICHIA made phosphors, referred to as M1 and M2 have been studied. The M1 mixture uses high efficient P-22 type green phosphor while M2 mixture uses the wide spectrum green phosphor Y₂SiO₅:Tb. As a result of our investigation, we were able to identify phosphor powder mixes capable of emitting white light under continuous dc electron beam excitation at accelerating energies of up to 8 kW. The prepared mixes exhibit stable light emission and color characteristics while maintaining the efficiency up to 40 Lm/Wt.