Research On Low Melting Luminescent Glass For White-light-LED

White-light emitting diodes (LED) possess such excellent performance as low power consumption, long lifetime, environmental protection and fast response time, and so on. Along with increasing of LED luminous efficiency and declining of manufacture costs, it is forecasted that white-light LED will become the new generation lighting and replace incandescent lamp, fluorescent lamp and high intensity discharge lamp and other types of lamp. The synthesis and characterization of phosphors used for white LED were paid more attention with the extension of application and the development of preparation technology in white LED. Especially, the properties of phosphor excited by blue light affect directly the quality of white LED. This article summarizes the research status in quo of white LED's, will compare the advantages and disadvantages between the realization of white ways, the study proposed the need for fluorescent glass.A series of phosphor doped fluorescent glass based on Li2O-B2O3 low melting pure borate,Na2O-Al2O3-B2O3 borate, and Na2O-Al2O3-B2O3-SiO2 borosilicate glass C, Li2O-ZnO-B2O3-SiO2 borosilicate glass and Na2O-ZnO-B2O3-SiO2 borosilicate glass was prepared by two-step method. The phase's structures of samples were analyzed by X-ray Powder diffraction meter (XRD). Excitation spectra and emission spectra of samples were measured by fluorescence spectrometer. Microstructure and grain shape of samples were identified by scanning electron microscopy (SEM) and super depth of field microscope. Particle size distributions of phosphors were measured by grain size instrument.1. The phase of YAG phosphors did not change as the treated temperature arises. But its cell parameters increase and the emission bands decrease. The color coordinates did not change significantly when temperature below 900℃. The emission bands and color coordinates were not affected by treated time and atmosphere.2. Borosilicate glass C is more appropriate than pure borate A and borate low melting glass B as the base of fluorescent glass. The emission peak and its shape are not affected by the changes of phosphors'quality adopted in. the intensity of emission bands increased first and than decreased as the phosphor adopted increased. Color coordinates alter slightly when adopted quality increase. The best ratio of glass and YAG phosphors is 1:0.5.3. The based glass zinc borosilicate glass was molded by casting and water quenching, marked as D and Dw respectively. The serials of D and Dw fluorescent glass was prepared by two-step method. The emission peak and its shape are not affected by the changes of phosphors'quality adopted in. The intensity of emission bands increased first and than decreased as the phosphor adopted increased. Color coordinates alter slightly when adopted quality increase. The best ratio of glass and YAG phosphors is 1:0.5～1:0.7.4. The serials of EA/EN fluorescent glass based on sealing glass E, were sintered in air and N2 atmosphere respectively. The serial of EN is better than EA. The intensity of emission bands increased as the phosphor adopted increased in EA. The intensity of emission bands increased first and than decreased as the phosphor adopted increased in EN. Color coordinates alter slightly when adopted quality increase first and than decreased as the phosphor adopted increased. The best ratio of glass and YAG phosphors is 1:0.3～1:0.5.The Project was supported by Educational Commission of Hubei Province of China (20091g0041).