||A white-light-emitting diode (WLED) was fabricated by precoating blue/yellow phosphors onto a near ultraviolet (NUV) LED chip. When the WLED operated under a direct current (DC) of 20 mA at room temperature, the color temperature T-c, the color-rendering index R-a, and the Commission Internationale de l'Eclairage chromaticity coordinate (x, y) are calculated to be 5998 K, 90.3 and (0.3253, 0.2822), respectively. With increasing DC from 10 to 40 mA, both the coordinates x and y of the WLED trend to decrease slightly, and consequently the R-a and the T-c decreases and increases, respectively. Compared with conventional "blue chip + yellow phosphor (YAG)" WLED, the "NUV chip + blue/yellow phosphor" WLED shows higher...
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