【摘要】：白光LED照明技術(shù)因其具有節(jié)能、安全穩(wěn)定、環(huán)保和使用壽命長(zhǎng)等特點(diǎn),被稱為繼白熾燈、節(jié)能燈之后的新一代綠色照明光源。本文對(duì)白光LED的發(fā)展現(xiàn)狀,發(fā)光機(jī)理,制備方法以及常用的熒光粉表征手段進(jìn)行了綜述。對(duì)白光LED的實(shí)現(xiàn)方式——用GaInN藍(lán)光芯片激發(fā)黃色熒光粉或GaInN藍(lán)光芯片激發(fā)紅綠色熒光粉；用紫外、近紫外的芯片激發(fā)RGB三基色熒光粉；采用紅綠藍(lán)芯片組合發(fā)射白光等方式進(jìn)行了分析比較,得出結(jié)論：發(fā)黃光的YAG:Ce3+熒光粉由于其制備方便、制作成本低是目前最易實(shí)現(xiàn)工業(yè)化生產(chǎn)的材料；而紅色熒光粉是目前最亟需的熒光材料,研究制備一種發(fā)光效率高、發(fā)光性能穩(wěn)定的紅色熒光粉對(duì)發(fā)光和顯示領(lǐng)域都有極大的積極作用。本論文采用高溫固相法制備了YAG:Ce3+熒光粉,并通過(guò)X射線衍射(XRD)、熒光光譜(PL)、掃描電子顯微鏡(SEM)等測(cè)試手段,對(duì)經(jīng)固相反應(yīng)法制備的YAG:Ce3+熒光粉樣品的材料特性與發(fā)光性能進(jìn)行了表征。研究表明,通過(guò)高溫固相法可以制備出發(fā)光性能良好的Ce3+摻雜的YAG熒光粉,得到的材料形貌為球形,結(jié)晶性和分散性良好,發(fā)黃綠光。通過(guò)實(shí)驗(yàn)確定了最佳反應(yīng)時(shí)間,由對(duì)比得知樣品在反應(yīng)溫度1500℃比在1350℃下發(fā)光強(qiáng)度更高,發(fā)光強(qiáng)度隨反應(yīng)溫度升高而得到增強(qiáng)。利用水熱法制備了球型紅色熒光粉CaWO4:Sm3+,通過(guò)XRD、PL、SEM等測(cè)試手段,對(duì)其發(fā)光性能進(jìn)行了表征。實(shí)驗(yàn)研究了摻雜濃度、反應(yīng)時(shí)間等條件的改變對(duì)于樣品的形貌以及發(fā)光性能的影響。通過(guò)不同摻雜濃度的對(duì)比實(shí)驗(yàn),可以發(fā)現(xiàn)Sm3+摻雜量為6%時(shí)CaWO4:Sm3+的發(fā)光性能最優(yōu),得到的產(chǎn)物其晶相為四方相的白鎢礦結(jié)構(gòu),具有良好的球形形貌,發(fā)射峰位置為647nm發(fā)紅光。最后通過(guò)ZEMAX軟件對(duì)白光LED的發(fā)光進(jìn)行了模擬,更好的了解LED的工作原理和光學(xué)特性。
[Abstract]:White light LED lighting technology is called a new generation green lighting source after incandescent lamp and energy saving lamp because of its characteristics of energy saving, safety and stability, environmental protection and long service life. In this paper, the development of white LED, luminescence mechanism, preparation methods and common methods of characterization of phosphors are reviewed. The way to realize white LED is to use GaInN blue chip to excite yellow phosphor or GaInN blue chip to excite red and green phosphor, to use ultraviolet, near ultraviolet chip to excite RGB tricolor phosphor. By using the combination of red, green and blue chips to emit white light, it is concluded that the yellowish YAG:Ce3 phosphors are the most convenient materials for industrial production because of their convenient preparation and low production cost. Red phosphors are the most needed fluorescent materials at present. The preparation of a kind of red phosphors with high luminescence efficiency and stable luminescence performance has a great positive effect on the luminescence and display fields. In this paper, YAG:Ce3 phosphors were prepared by high temperature solid state method. X-ray diffraction (XRD) (XRD), fluorescence spectrum (PL),) scanning electron microscope (SEM) was used to measure the phosphors. The properties and luminescence properties of YAG:Ce3 phosphors prepared by solid state reaction were characterized. The results show that Ce3 doped YAG phosphors with good luminescence properties can be prepared by high temperature solid state method. The obtained YAG phosphors have spherical morphology, good crystallinity and dispersion, and yellowish green. The optimum reaction time was determined by experiments. The results showed that the luminescence intensity of the sample was higher at 1500 鈩，

本文編號(hào)：2139540