White organic light-emitting devices with mixed interfaces between light emitting layers

Abstract

White organic light-emitting devices with mixed interfaces between emitting layers (MI-EML WOLEDs) showed luminance and efficiency as large as 26213cd∕m2 and 9.85cd∕A. Efficiencies of MI-EML WOLEDs were about 1.5 times better than those of conventional three-EML WOLEDs for luminance of 1000–5000cd∕m2, and their half-decay lifetime showed 3.1 times improvement. Note that if the authors operate typical active-matrix mobile-phone displays based on combination of WOLED and color filters to produce standard white emission for high definition televisions and illumination sources, MI-EML WOLEDs will have advantages of 25% less power consumption and 2.8 times longer lifetime over conventional three-EML WOLEDs.

Control of device performances of phosphorescent white organic light-emitting diodes by managing charge transport properties of host materials

“…Sun and Forrest [15] demonstrated that the three-layer emitting structure with the cascading highest occupied molecular orbital (HOMO) and the lowest unoccupied molecular orbital (LUMO) energy level was useful in expanding the recombination zone, and efficiency was improved. Lee et al [16] reported that WOLEDs with mixed interfaces between the emitting layers showed high luminance and efficiency. Other than these, tandem WOLEDs with two emitting units in series showed a current efficiency of 17.14 cd/A with CIE coordinates of (0.28, 0.41) [19].…”

“…In recent years, many device architectures of white organic light-emitting diodes (WOLEDs) have been developed to improve their efficiency, luminance, color coordinates, and color stability [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18][19]. Among them, WOLEDs based on stacked emitting structures are gaining interest due to their merits of high luminance and quantum efficiency.…”

High stability white organic light-emitting diode fabricated with the deposition of solvent premixed sources

“…However, their efficiency needs to be improved. Further, the difficulty of accurately controlling the doping concentrations increases when several dyes are codoped [12]. This paper presents a method for the fabrication of single-EML WOLEDs via evaporation deposition using solvent premixed sources.…”

Correlation between host material compositions and performances in organic white-light-emitting diodes with blue/orange/blue emitting stacked structure

“…In particular, multi-stacked emitting layers structure has been known to give good color stability, good color tuning and high efficiency due to the control of charge distribution [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18][19][20]. The change of number of stacked emission layers and/or thickness of emitting layers were popular ways to control color performances of PHWOELDs although doping concentration management and energy level matching of organic layers have been developed as an approach to tune device performances of OWLEDs.…”