long service life [1–3]. There are mainly three methods to fabricate white LEDs [4, 5]. The first way is bine a yellow-emitting phosphor (YAG:Ce3+) with a blue chip (*460 nm). heless, white light produced by blue LED and yellow phosphors has many defects, for example the lack of red POnent in its POsition and low color render index. The second way is bine blue, green and red LEDs. But in this way the luminescence brightness of different LED devices changes differently with temperature increasing, caused by the color coordinates drifting of mixing white light. The third approach is to excite blue, green and red phosphors using a NUV LED or blue LED. Comparison of two previous methods, the third approach should be the most superior way to achieve high performance W-LEDs. At present, the most
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