| With the development of society, people’s requirements for display and relative light sourceare increasing continuously. In the projection display industry, the traditional light source isgenerally the gas discharge lamp or high pressure mercury lamp. The product life is only2000hours and it is easy to cause environmental pollution because of the contained mercurycomposition. The display light source of LPD (Laser Phosphor Display laser) technology hasseveral characteristics, such as long life, high efficiency, wide color gamut and mercury-free,which meets the need of environment protection, can fully replace the traditional high pressuremercury lamp products and is widely used in display industry. This technology obtains differentcolors of light by means of the monochromatic laser and rotating wheel which containingphosphors in various colors. At present, as one kind of excellent light conversion materials,phosphors are generally mixed with silicon or resin to obtain the required samples. But with theincrease of power, silicon and resin are likely to occur aging, cracking when they are long timeexposed to high temperature and to laser or UV irradiation, which does harm to the properties ofthe encapsulated phosphors and leads to a decline in brightness. Therefore, finding highperformance phosphors and changing the encapsulation means are the problems that should besolved quickly.Nitride phosphors have the advantages of high quantum efficiency, rich spectra, low thermalquenching, which can be used in LPD technology. In this paper, Eu2+doped CaAlSiN3phosphorswere prepared through high-temperature solid-state reaction. The phosphors were characterized byX-ray diffraciton (XRD), fluorescence spectrophotometer (PL). The experimental results showedthat the crystallization and luminous intensity of phosphors were the best in the condition ofreaction temperature-1700℃, reaction pressure-0.65MPa, soaking time-3h. When the doping concentration of Eu2+was up to4mol%, the emission intensity reached maximum. If wecontinued to increase concentration, the concentration quenching and red shift would happen. Inaddition, we can control the emission peak of phosphors through changing the matrix cation.According to the problem of silicon and resin, in this letter we propose the feasibility of usingglass powders as the binder to prepare the CaAlSiN2+3:Euphosphor-in-glass.B2O3-Bi2O3-Al2O3-ZnO glass powder showed good sintering behavior with CaAlSiN23:Eu+phosphors at around550℃. The phosphor-in-glass has flat surface with a thickness of about100μm. From the images of FE-SEM and confocal laser scanning microscope, the uniformdistribution of phosphor particles inside the phosphor-in-glass was vividly and clearly observed.And the luminescent property of phosphors was not greatly affected by glasses, as shown influorescence spectra. When the volume radio of CaAlSiN+3:Eu2phosphors was50%, the sampleexhibited low thermal quenching and high flexural strength of28.5MPa. The CaAlSiN3:Eu2+phosphor-in-glass has a good application prospect because of its excellent properties.We also have prepared YAG:Ce3+phosphor-in-glass and made some coMParisons withCaAlSiN3:Eu2+phosphor-in-glass. Bismuth borate glasses and YAG:Ce3+phosphors were made bysome oxides, so a small contact angle can be formed between them, so bismuth borate glasseshave better wettability on YAG:Ce3+phosphor particles than CaAlSiN+3:Eu2particles. In addition,YAG:Ce3+phosphor-in-glass has higher flexural strength and transmittance and bismuth borateglasses have a smaller iMPact on luminous intensity of YAG:Ce3+phosphors. Therefore, throughthe analys is of YAG:Ce3+and CaAlSiN+3:Eu2phosphor-in-glass, we concluded that the bismuthborate glass was more suitable for oxide phosphors and it was necessary to looking for a glasssystem which was more suitable for nitride phosphors. |
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