The Study of Optical Properties as Glass Composition of Bi2O3-Based Glass/Phosphor Mixed Paste

Recently, White light emitting diodes (WLEDs) have been studied because of many advantages such as lower energy consumption, fast response, high brightness. Glass frit has been interested in LED packages due to their superior properties such as long-term stability and permeability. To maximize the LED light emission characteristic, the glass frit was required a low firing temperature and high refractive index. We selected the bismuth-based glass due to their low melting and high refractive index. This study was investigated characteristics of glass according to the influence of the glass within Bi2O3 content and this glass characteristic change was studied the effects on the optical properties of LED package structure. The properties changes of the glass frit affect the optical property of the mixed paste. With higher contents of Bi203 glass composition, the transmittance and emission intensity of the mixed paste was increased. These results suggest that the difference in refractive index between the phosphor and glass frit is minimized, the loss of light is minimized.