Organic light emitting diode fluorescence emission

In addition, they are widely used as fluorescent molecules for laser dyes,14 in the emission layer in organic light-emitting diodes,15 and as the fluorophore in fluorescent sensors.1617 Their fluorescence properties are known to depend upon the nature and position of substituents, and therefore several groups have constructed coumarin libraries to discover better coumarin-based materials. 

The operation of organic light-emitting diodes (OLEDs) involves charge injection from electrodes, transport of charge carriers, recombination of holes and electrons to generate electronically excited states or excitons, followed by their deactivation by emission of either fluorescence or phosphorescence. The main factors that determine luminous and external quantum efficiencies are the following ... 

The principle of Dexter energy transfer is frequently applied for commercial manufacture of white organic light-emitting diodes with fluorescent tubes and energy up conversion systems such as blue light emission [16] and while light emission [17], by triplet-triplet annihilation. 

Figure 5.2 Schematic of organic excitation and detection system with microfluidic device for fluorescence detection. Green organic light-emitting diode (OLED) acts as the light source, the polydimethylsiloxane (PDMS) microfluidic chip contains the dye detection volume, and polarizer 2 is used to filter out the excitation light and allows only the emission signal to pass through to the organic photodiode (OPD).

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