Skip to content

Research at St Andrews

Transparent organic light-emitting diodes with different bi-directional emission colors using color-conversion capping layers

Research output: Contribution to journalArticle


Jonghee Lee, Tae-Wook Koh, Hyunsu Cho, Tobias Schwab, Jae-Hyun Lee, Simone Hofmann, Jeong-Ik Lee, Seunghyup Yoo, Karl Leo, Malte Christian Gather

School/Research organisations


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



Original languageEnglish
Pages (from-to)180-184
JournalJournal of Luminescence
Early online date25 Feb 2015
Publication statusPublished - Jun 2015

    Research areas

  • Down-conversion white OLED, Color conversion capping layer, Transparent OLED, Bi-directional OLED

Discover related content
Find related publications, people, projects and more using interactive charts.

View graph of relations

Related by author

  1. Bipyridine-containing host materials for high performance yellow thermally activated delayed fluorescence-based organic light emitting diodes with very low efficiency roll-off

    Chen, D., Pachai, R., Tenopala Carmona, F., Carpenter-Warren, C. L., Cordes, D. B., Keum, C., Slawin, A. M. Z., Gather, M. C. & Zysman-Colman, E., 21 Nov 2019, In : Advanced Optical Materials. Early View, 1901283.

    Research output: Contribution to journalArticle

  2. Developing next-generation brain sensing technologies: a review

    Robinson, J. T., Pohlmeyer, E., Gather, M. C., Kemere, C., Kitching, J. E., Malliaras, G. G., Marbleston, A., Shepard, K. L., Stieglitz, T. & Xie, C., 15 Nov 2019, In : IEEE Sensors Journal. 19, 22, p. 10163 - 10175 13 p., 8772197.

    Research output: Contribution to journalReview article

  3. 1,3,4-oxadiazole-based deep-blue thermally activated delayed fluorescence emitters for organic light emitting diodes

    Li, Z., Li, W., Keum, C., Archer, E., Zhao, B., Slawin, A. M. Z., Huang, W., Gather, M. C., Samuel, I. D. W. & Zysman-Colman, E., 10 Oct 2019, In : Journal of Physical Chemistry. 123, 40, p. 24772-24785

    Research output: Contribution to journalArticle

  4. Narrowband organic light-emitting diodes for fluorescence microscopy and calcium imaging

    Murawski, C., Mischok, A., Booth, J. H., Kumar, J. D., Archer, E., Tropf, L. C., Keum, C., Deng, Y., Yoshida, K., Samuel, I. D. W., Schubert, M., Pulver, S. & Gather, M. C., 5 Sep 2019, In : Advanced Materials. Early View, 8 p.

    Research output: Contribution to journalArticle

  5. Low-threshold polariton lasing in a highly disordered conjugated polymer

    Wei, M., Rajendran, S. K., Ohadi, H., Tropf, L. C., Gather, M. C., Turnbull, G. A. & Samuel, I. D. W., 27 Aug 2019, In : Optica. 6, 9, p. 1124-1129 6 p., 362590.

    Research output: Contribution to journalArticle

Related by journal

  1. Factors controlling the thermoluminescence spectra of rare earth doped calcium fluoride

    Wang, Y., Zhao, Y., White, D., Finch, A. A. & Townsend, P. D., Apr 2017, In : Journal of Luminescence. 184, p. 55-63 9 p.

    Research output: Contribution to journalArticle

  2. Spectral changes and wavelength dependent thermoluminescence of rare earth ions after X-ray irradiation

    Townsend, P. D., Finch, A. A., Maghrabi, M., Ramachandran, V., Vázquez, G. V., Wang, Y. & White, D. R., Dec 2017, In : Journal of Luminescence. 192, p. 574-581 8 p.

    Research output: Contribution to journalArticle

  3. Energy dependence of radioluminescence spectra from strontium titanate

    Wang, Y., Zhao, Y., Zhang, Z., Zhao, C., Wu, X., Finch, A. A. & Townsend, P. D., Oct 2015, In : Journal of Luminescence. 166, p. 17-21

    Research output: Contribution to journalArticle

  4. On the spectra luminescence properties of charoite silicate

    Garcia-Guinea, J., Townsend, P. D., Can, N., Correcher, V., Sanchez-Munoz, L., Finch, A. A., Hole, D., Avella, M., Jimenez, J. & Khanlary, M., Mar 2008, In : Journal of Luminescence. 128, p. 403-412 10 p.

    Research output: Contribution to journalArticle

ID: 199001849