Rare Earth Doped Glasses For Conversion Of Near Ultraviolet Light To White Light

Solid state lighting through light emitting diode (LED) has the potential to displace the conventional incandescent of fluorescent lamps for illumination because of its high efficiency, long lifetime and robust lamp structure. One approach to form white light is to use near ultraviolet (NUV) LEDs to excite phosphors that emit blue, green and red light simultaneously by down conversion. The rare earth co-doped glasses that can emit white light under NUV excitation are produced. Their chromaticity co-ordinates vary with the composition of glasses and excitation wavelength. The optimised doped glass compositions are obtained by considering the colour balance. The effects of host glasses on luminescence intensity are investigated.