A Novel Preparation of Special-Shaped Phosphors-in-Glass by Gel Casting with Isobam for High-Power WLEDs Lighting

Abstract

Phosphors-in-glass (PiGs) regarded as a promising phosphor-converter for white light emitting diodes (WLEDs) is being researched widely. However, there are few reports on the effect of changing the shape of PiGs on the color rendering index (CRI) and heat dissipation of WLEDs. In this paper, gel casting with Isobam was first attempted in preparing special-shaped PiGs successfully. It exhibited that 76 wt.% was the optimum solid content based on the rheological properties of slurry and the shrinkage of green bodies. The sintering rate should be kept at a low speed and glass transition temperature (Tg) of glass powders must be higher than sublimation temperatures (Ts) of APS and Isobam. The CRI of PiGs was increased by about 27% after changing the shape of PiGs from cylinder to dome. Most importantly, operating temperature also reduced effectively the increase of the surface area of PiGs. Therefore, changing the shape of PiGs by gel casting with Isobam is a creative way for high-power WLEDs lighting.

(Sr, Ca)AlSiN3:Eu2+ Phosphor-Doped YAG:Ce3+ Transparent Ceramics as Novel Green-Light-Emitting Materials for White LEDs

“…YAG:Ce 3+ phosphor transparent ceramics (TCs) can be excited by approximately 450–460 nm of blue light, to produce white LEDs/LDs [ 1 , 2 , 3 ]. These ceramics have high lumen-efficiency and thermal stability compared to phosphors in glass (PiG) [ 4 , 5 , 6 ] and single crystals (SC) [ 7 , 8 , 9 ]. However, the lack of red- and green-light components causes a low color-rendering-index (CRI) in the spectrum [ 2 , 10 ].…”