Editing Light-emitting diode (section)

==Organic light-emitting diodes (OLEDs)==
{{Main|OLED}}

In an organic light-emitting diode ([[OLED]]), the [[Electroluminescence|electroluminescent]] material composing the emissive layer of the diode is an [[organic compound]]. The organic material is electrically conductive due to the [[Delocalized electron|delocalization]] of [[Pi bond|pi electrons]] caused by [[Conjugated system|conjugation]] over all or part of the molecule, and the material therefore functions as an [[organic semiconductor]].<ref>{{Cite journal |last1 = Burroughes |first1 = J. H. |last2 = Bradley | first2 = D. D. C. |last3 = Brown |first3 = A. R. |last4 = Marks |first4 = R. N. |last5 = MacKay |first5 = K. |last6 = Friend |first6 = R. H. |last7 = Burns |first7 = P. L. |last8 = Holmes |first8 = A. B. |doi = 10.1038/347539a0 |title = Light-emitting diodes based on conjugated polymers |journal = Nature |volume = 347 |issue = 6293 |pages = 539–541 |year = 1990 |bibcode=1990Natur.347..539B|s2cid = 43158308 }}</ref> The organic materials can be small organic [[molecule]]s in a [[crystal]]line [[phase (matter)|phase]], or [[polymer]]s.<ref name="OLEDSolidState">{{Cite conference |last1=Kho |first1=Mu-Jeong |last2=Javed |first2=T. |last3=Mark |first3=R. |last4=Maier |first4=E. |last5=David |first5=C |title=Final Report: OLED Solid State Lighting |conference=Kodak European Research |date=March 4, 2008 |location=Cambridge Science Park, Cambridge, UK}}</ref>

The potential advantages of OLEDs include thin, low-cost displays with a low driving voltage, wide viewing angle, and high contrast and color [[gamut]].<ref name="bardsley">{{Cite journal |last1 = Bardsley |first1 = J. N. |doi = 10.1109/JSTQE.2004.824077 |title = International OLED Technology Roadmap |journal = IEEE Journal of Selected Topics in Quantum Electronics |volume = 10 | issue = 1 |pages = 3–4 |year = 2004 |bibcode = 2004IJSTQ..10....3B |s2cid = 30084021 |url = https://zenodo.org/record/1232213 }}</ref> Polymer LEDs have the added benefit of printable and [[flexible organic light-emitting diode|flexible]] displays.<ref>{{Cite journal |last1 = Hebner | first1 = T. R. |last2 = Wu |first2 = C. C. |last3 = Marcy |first3 = D. |last4 = Lu |first4 = M. H. |last5 = Sturm |first5 = J. C. |title = Ink-jet printing of doped polymers for organic light emitting devices |doi = 10.1063/1.120807 |journal = Applied Physics Letters |volume = 72 |issue = 5 | page = 519 |year = 1998 |bibcode = 1998ApPhL..72..519H | s2cid = 119648364 }}</ref><ref>{{Cite journal |last1 = Bharathan |first1 = J. |last2 = Yang |first2 = Y. |doi = 10.1063/1.121090 |title = Polymer electroluminescent devices processed by inkjet printing: I. Polymer light-emitting logo |journal = Applied Physics Letters |volume = 72 |issue = 21 |page = 2660 |year = 1998 |bibcode = 1998ApPhL..72.2660B |s2cid = 44128025 }}</ref><ref>{{Cite journal |last1 = Gustafsson |first1 = G. |last2 = Cao |first2 = Y. |last3 = Treacy |first3 = G. M. |last4 = Klavetter |first4 = F. |last5 = Colaneri |first5 = N. |last6 = Heeger |first6 = A. J. |doi = 10.1038/357477a0 |title = Flexible light-emitting diodes made from soluble conducting polymers |journal = Nature |volume = 357 |issue = 6378 |pages = 477–479 |year = 1992 |bibcode=1992Natur.357..477G|s2cid = 4366944 }}</ref> OLEDs have been used to make visual displays for portable electronic devices such as cellphones, digital cameras, lighting and televisions.<ref name="OLEDSolidState" /><ref name="bardsley" />