Properties of a blue-emitting IR pumped YF3:Yb, Tm diode

A practical blue-light-emitting diode using the IR pumped phosphor YF
3
:Yb, Tm is described. The emission spectrum of the coated GaAs:Si diode exhibits peaks at 4750, 6450, 7000, 8000, and 9500 Å. Visually, the unfiltered emission appears blue with a purple cast due to the red 6450 Å peak. A luminance as high as 60 fL in the blue has been achieved using reasonable current densities for the pump diode.