Organic blue emitter

L.M. Leung, W.Y. Lo, K.M. Lee, and W.K. Choi, A high-efficiency blue emitter for small molecule-based organic light-emitting diode, J. Am. Chem. Soc., 122 5640-5641 (2000). 

FIGURE 7.8 Molecular structures of several organic emitter materials. Their positions on the diagram are arranged as a function of their emission color with blue emitters on the left, green in the center, and red on the right hand side. 

Transparent electrodes also allow the fabrication of stacked LEDs with electrodes within the device structure. By applying voltages between different adjacent pairs of electrodes, it is possible to control the amount of emission from each layer and hence to control the color of the emission (see Fig. 5.22), taking advantage of the fact that blue emitters, for example, are transparent to red, green and blue emission. This strategy was first demonstrated in polymer LEDs by Martens et al.,99 and has also been used in molecular organic LEDs.100... 

The fluorescence color converter technique [32] can, in principle, overcome much of this power loss by replacing the white light emitter with a blue-emitting organic stack, and the absorbing filters with green and red fluorescent dyes. Thus when a green pixel is desired, the OLED underneath is turned on and the blui... 

Some of the derivatives 96 show high photoluminescence quantum yields of up to 73%, and can be applied as blue and green polymeric emitters in organic materials-based LEDs [122]. 

G. Lei, L. Wang, and Y. Qiu, Blue phosphorescent dye as sensitizer and emitter for white organic light-emitting diodes, Appl. Phys. Lett., 85 5403-5405 (2004). 

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