Effects of White Organic Light-Emitting Devices Using Color Conversion Films on Electroluminescence Spectra

The authors report a novel white organic light-emitting device (WOLED), which uses a strategy of exciting organic/inorganic color conversion film with a blue organic light-emitting diode (OLED). The luminescent layer of the blue OLED was prepared by use of CBP host blended with a blue highly fluorescent dye N-BDAVBi. The organic/inorganic color conversion film was prepared by dispersing a mixture of red pigment VQ-D25 and YAG: Ce3+ phosphor in PMMA. The authors have achieved a novel WOLED with the high color stability by optimizing the thickness and fluorescent pigment concentration of the color conversion film. When the driving voltage varied between 6 and 14 V, the color coordinates (CIE) varied slightly from (0.354, 0.304) to (0.357, 0.312) and the maximum current efficiency is about 5.8 cd center dot A(-1) (4.35 mA center dot cm(-2)), the maximum brightness is 16 800 cd center dot m(-2) at the operating voltage of 14 V.