Transparent organic light-emitting diodes with different bi-directional emission colors using color-conversion capping layers
Abstract
We report a study on transparent organic light-emitting diodes (OLEDs) with different bidirectional emission colors, enabled by color-conversion organic capping layers. Starting from a transparent blue OLED with an uncapped Ag top electrode exhibiting an average transmittance of 33.9%, a 4-(Dicyanomethylene)-2-methyl- 6-(4-dimethylaminostyryl)-4Hpyran (DCM)-doped tris-(8-hydroxy-quinolinato)-aluminium (Alq3) capping layer is applied to achieve color-conversion from blue to orange-red on the top side while maintaining almost unchanged device transmittance. This color-conversion capping layer does not only change the color of the top side emission, but also enhances the overall device efficiency due to the optical interaction of the capping layer with the primary blue transparent OLED. Top white emission from the transparent bi-directional OLED exhibits a correlated color temperature around 6,000K-7,000K, with excellent color stability as evidenced by an extremely small variation in color coordinate of ∆(x,y) = (0.002, 0.002) in the forward luminance range of 100-1000 cd m-2. At the same time, the blue emission color of bottom side is not influenced by the color conversion capping layer, which finally results in different emission colors of the two opposite sides of our transparent OLEDs
Citation
Lee , J , Koh , T-W , Cho , H , Schwab , T , Lee , J-H , Hofmann , S , Lee , J-I , Yoo , S , Leo , K & Gather , M C 2015 , ' Transparent organic light-emitting diodes with different bi-directional emission colors using color-conversion capping layers ' , Journal of Luminescence , vol. 162 , pp. 180-184 . https://doi.org/10.1016/j.jlumin.2015.02.032
Publication
Journal of Luminescence
Status
Peer reviewed
ISSN
0022-2313Type
Journal article
Rights
Copyright 2015 Elsevier B.V. All rights reserved. © 2014. Elsevier Inc. All rights reserved. This is the author’s version of a work that was accepted for publication in Journal of Luminescence. Changes resulting from the publishing process, such as peer review, editing, corrections, structural formatting, and other quality control mechanisms may not be reflected in this document. Changes may have been made to this work since it was submitted for publication. A definitive version was subsequently published in Journal of Luminescence, 162, June 2015 DOI http://dx.doi.org/10.1016/j.jlumin.2015.02.032
Collections
Items in the St Andrews Research Repository are protected by copyright, with all rights reserved, unless otherwise indicated.