OSA's Digital Library

Optics Express

Optics Express

  • Editor: C. Martijn de Sterke
  • Vol. 15, Iss. 20 — Oct. 1, 2007
  • pp: 13288–13294

Improving the viewing angle properties of microcavity OLEDs by using dispersive gratings

Wallace C. H. Choy and C. Y. Ho  »View Author Affiliations

Optics Express, Vol. 15, Issue 20, pp. 13288-13294 (2007)

View Full Text Article

Enhanced HTML    Acrobat PDF (163 KB)

Browse Journals / Lookup Meetings

Browse by Journal and Year


Lookup Conference Papers

Close Browse Journals / Lookup Meetings

Article Tools



The changes of emission peak wavelength and angular intensity with viewing angles have been issues for the use of microcavity OLEDs. We will investigate Distributed Bragg Gratings (DBRs) constructed from largely dispersive index materials for reducing the viewing angle dependence. A DBR stack mirror, aiming at a symmetric structure and less number of grating period for a practical fabrication, is studied to achieve a chirp-featured grating for OLEDs with blue emission peak of 450nm. For maximizing the compensation of the viewing angle dependence, the effects of dispersive index, grating structure, thickness of each layer of the grating, grating period and chirp will be comprehensively investigated. The contributions of TE and TM modes to the angular emission power will be analyzed for the grating optimization, which have not been expressed in detail. In studying the light emission of OLEDs, we will investigate the Purcell effect which is important but has not been properly considered. Our results show that with a proper design of the DBR, not only a wider viewing angle can be achieved but also the color purity of OLEDs can be improved.

© 2007 Optical Society of America

OCIS Codes
(050.2770) Diffraction and gratings : Gratings
(230.3670) Optical devices : Light-emitting diodes
(250.3680) Optoelectronics : Light-emitting polymers

ToC Category:
Diffraction and Gratings

Original Manuscript: July 12, 2007
Revised Manuscript: September 21, 2007
Manuscript Accepted: September 21, 2007
Published: September 28, 2007

Wallace C. H. Choy and C. Y. Ho, "Improving the viewing angle properties of microcavity OLEDs by using dispersive gratings," Opt. Express 15, 13288-13294 (2007)

Sort:  Author  |  Year  |  Journal  |  Reset  


  1. A. Dodabalapur, L. J. Rothberg, and T. M. Miller, "Color variation with electroluminescent organic semiconductors in multimode resonant cavities," Appl. Phys. Lett. 65, 2308-2310 (1994). [CrossRef]
  2. D. G. Lidzey, D. D. C. Bradley, S. J. Martin, and M. A. Pate, "Pixelated multicolor microcavity displays," IEEE J. Select.Topics in Quantum Electron. 4, 113-118 (1998).Q1 [CrossRef]
  3. D. G. Lidzey, M. A. Pate, D. M. Whittaker, D. D. C. Bradley, M. S. Weaver, T. A. Fisher, and M. S. Skolnick, "Control of photoluminescence emission from a conjugated polymer using an optimised microactivity structure," Chem. Phys. Lett. 263, 655-660 (1996). [CrossRef]
  4. F. S. Juang, L. H. Laih, C. J. Lin, and Y. J. Hsu, "Angular dependence of the sharply directed emission in organic light emitting diodes with a microcavity structure," Jap. J. Appl. Phys. 41, 2787-2789 (2002).Q2 [CrossRef]
  5. K. Neyts, P. D. Visschere, D. K. Fork, and G. B. Anderson, "Semitransparent metal or distributed Bragg reflector for wide-viewing-angle organic light-emitting-diode microcavities," J. Opt. Soc. Amer. B 17, 114-119 (2000). [CrossRef]
  6. N. Tessler, S. Burns, H. Becker, and R. H. Friend, "Suppressed angular color dispersion in planar microcavities," Appl. Phys. Lett. 70, 556-558 (1997). [CrossRef]
  7. L. Hou, Q. Hou, Y. Peng, and Y. Cao, "All-organic flexible polymer microcavity light-emitting diodes using 3M reflective multilayer polymer mirrors," Appl. Phys. Lett. 87, 243504 (2005). [CrossRef]
  8. C. He, Y. Tang, X. Zhoa, H. Xu, D. Lin, H. Luo, and Z. Zhou, "Optical dispersion properties of tetragonal relaxor ferroelectric single crystals 0.65Pb(Mg1/3Nb2/3)O3-0.35PbTiO3," Opt. Mat. 29, 1055-1057 (2007). [CrossRef]
  9. J. L. H. Chau, Y.M. Lin, A.K. Li, W.F. Su, K.S. Chang, S. L.C. Hsu, and T.L. Li, "Transparent high refractive index nanocomposite thin films," Mater. Lett. 61, 2908-2910 (2007). [CrossRef]
  10. L. H. Smith, J. A. E. Wasey, and W. L. Barnes, "Light outcoupling efficiency of top-emitting organic light-emitting diodes," Appl. Phys. Lett. 84, 2986-2988 (2004). [CrossRef]
  11. C. L. Lin, T. Y. Cho, C. H. Chang, and C. C. Wu, "Enhancing light outcoupling of organic light-emitting devices by locating emitters around the second antinode of the reflective metal electrode," Appl. Phys. Lett. 88, 081114 (2006). [CrossRef]
  12. E. M. Purcell, "Spontaneous emission probabilities at radio frequencies," Phys. Rev. 69, 681-684 (1946).
  13. W. C. H. Choy and E. H. Li, "The applications of interdiffused quantum well in normally-on electro-absorptive Fabry-Perot reflection modulator," IEEE J. Quantum Electron. 33, 382-393 (1997). [CrossRef]
  14. O. H. Crawford, "Radiation from oscillating dipoles embedded in a layered system," J. Chem. Phys. 89, 6017-6027 (1989). [CrossRef]
  15. V. Bulovic, V. B. Khalfin, G. Gu, P. E. Burrows, D. Z. Garbuzov, and S.R. Forrest, "Weak microcavity effects in organic light-emitting devices," Phys. Rev. B 58, 3730-3740 (1998). [CrossRef]
  16. X. W. Chen, W. C. H. Choy and S. He, "Efficient and rigorous modeling of light emission in planar multilayer organic light-emitting diodes", IEEE J. Display Technol. 3, 110-117 (2007);Q3K. Neyts, "Simulation of light emission from thin-film microcavities," J. Opt. Soc. Amer. A 15, 962-970 (1998);W. Lukosz, "Theory of optical-environment-dependent spontaneous emission rates for emitters in thin layers,’’Phys. Rev. B 22, 3030-3038 (1980). [CrossRef]
  17. P. A. Hobson, J. A. E. Wasey, I. Sage, and W. L. Barnes, "The role of surface plasmons in organic light emitting diodes," IEEE J. Sel. Top. Quantum Electron. 8, 378-386 (2002).Q4 [CrossRef]
  18. R. H. Jordan, L. J. Rothberg, A. Dodabalapur, and R. E. Slusher, "Efficiency enhancement of microcavity organic light emitting diodes", Appl. Phys. Lett. 69, 1997-1999 (1996). [CrossRef]
  19. Y. Kijima, N. Asai and S. Tamura, "A Blue Organic Light Emitting Diode," Jap. J. Appl. Phys. 38, 5274-5277 (1999).Q5 [CrossRef]
  20. B. Deveaud, ed, The Physics of Semiconductor Microcavities: from fundamentals to nanoscale devices, (Wiley-VCY, 2007), Ch. 12, p.245.

Cited By

Alert me when this paper is cited

OSA is able to provide readers links to articles that cite this paper by participating in CrossRef's Cited-By Linking service. CrossRef includes content from more than 3000 publishers and societies. In addition to listing OSA journal articles that cite this paper, citing articles from other participating publishers will also be listed.


Fig. 1 Fig. 2 Fig. 3.
Fig. 4

« Previous Article  |  Next Article »

OSA is a member of CrossRef.

CrossCheck Deposited