High color purity phosphors of LaAlGe2O7 doped with Tm3+ and Er3+

Phosphors of LaAlGe2O7 doped with Tm3+ and Er3+ of high color purity, exhibiting a narrow band emission in the blue and green regions, were obtained. (La(1-x)Ln(x))AlGe2O7 (Ln=Tm,Er) powders are bright emitters, with chromaticity color coordinates that are comparable to or better than those of standard phosphors for display or lighting devices. The blue emission of the Tm3+-doped phosphor had CIE chromaticity coordinates (0.151, 0.033) with a dominant wavelength of 455 nm and a color purity of 94%. The Er3+-doped phosphor had color coordinates (0.249, 0.718), a dominant wavelength of 542 nm, and 92% purity.