Navigation Links
Organic light-emitting diodes
Date:11/8/2011

WASHINGTON, Nov. 7The search for innovative, cost-effective and energy-efficient solutions for display and lighting applications are the focus of ongoing intense worldwide photonics research and development activities. Organic light-emitting diodes (OLEDs)lightweight, potentially flexible, cheap-to-fabricate and highly energy-efficient lighting and display devicesoffer one solution in alternative energy lighting and display applications. To highlight breakthroughs in this area, the Optical Society (OSA (http://www.osa.org)) today published a special Focus Issue on OLEDs (http://www.opticsinfobase.org/oe/issue.cfm?volume=19&issue=106) in Energy Express (http://www.opticsinfobase.org/ee), a bi-monthly supplement to its open access journal Optics Express (http://www.opticsinfobase.org/oe/home.cfm). The issue is organized and edited by Guest Editors Emil J.W. List of the NanoTecCenter Weiz GmbH and Graz University of Technology in Austria, and Norbert Koch of the Institute of Physics, Humbolt University in Germany.

"OLEDs are amongst the most promising candidates for alternative display and lighting solutions," said List. "The exciting findings presented in this focus issue will ultimately translate into real-world applications, providing consumers with cost-effective technology while reducing electricity consumption."

More than 20 percent of the world's total electricity consumption is used for lighting applications. That number increases to an estimated 25 percent when including display and TV applications. OLEDs, along with inorganic solid-state lighting technologies, are considered to be on the forefront of 21st century display and lighting technologies. The widespread use of this technology could save hundreds of gigawatt hours (GWh) of power or millions of tons of coal per year.

"OLEDs can be found in a variety of everyday products such as television screens, computer monitors and smartphones," said Koch. "As use of these products becomes more widespread, the need for research and development also grows. The latest advances reflected in this focus issue are truly exceptional and will prove to be invaluable to advancements in lighting and display technology."

Key Findings and Select Papers

The following papers are some of the highlights of the Energy Express Focus Issue on OLEDs. All are included in Volume 19, issue S6 and can be accessed online at http://www.opticsinfobase.org/ee.

The outcoupling of light from an OLED may be tackled by different means, including optical feedback structures in the active layer, by high index-media in top-emitting OLED, by lens or microlens-like arrays, or by using microcavity effects in the active device. As reviewed and discussed by Simone Hofmann, Karl Leo and their colleagues from the Institute for Applied for Photophysics, TU Dresden in Germany, in particular top-emitting OLEDs seem to be beneficial for lighting and display applications. Here, non-transparent substrates are used. The authors review and discuss different optical effects of the microcavity structure and identify important loss mechanisms due to waveguiding and surface plasmons, and show that further improvement in light extraction is required to reach the targeted high outcoupling efficiencies.

Paper: "Top-Emitting Organic Light-Emitting Diodes (http://www.opticsinfobase.org/oe/abstract.cfm?uri=oe-19-106-A1250)," Optics Express, Vol. 19, Issue S6, pp. A1250-A1264 (2011).

A very practical approach to improve the outcoupling efficiency in OLEDs up to 60 percent is demonstrated by Ruth Shinar and Joseph Shinar from the U.S. Department of Energy's Ames Laboratory and Iowa State University, and coworkers, using index-matching microporous phase-separated films of polymer blends acting as random microlens-like arrays. They demonstrate that the use of such blended thin films provides an economical method independent of the OLED fabrication technique, for improving outcoupling.

Paper: "Microporous phase-separated films of polymer blends for enhanced outcoupling of light from OLEDs (http://www.opticsinfobase.org/oe/abstract.cfm?uri=oe-19-106-A1272)," Optics Express, Vol. 19, Issue S6, pp. A1272-A1280 (2011).

To overcome the losses at the organic layer/cathode interface and to optimize the optical path in the devices, Lian Duan, Yong Qiu and their colleagues from the Key Lab of Organic Optoelectronics and Molecular Engineering of Ministry of Education, Tsinghua University, and the R&D Center, Visionox Tech. Ltd, Beijing, introduce an approach by using a novel, rather thick, n-doped layer. Using a combination of a low-temperature-evaporable n-dopant KBH4 and a high charge carrier mobility electron transport material they show excellent performance of their devices due to reduced losses at the organic layer/cathode interface.

Paper: "Improving the performance of OLEDs by using a low-temperature-evaporable n-dopant and a high-mobility electron transport host (http://www.opticsinfobase.org/oe/abstract.cfm?uri=oe-19-106-A1265)," Optics Express, Vol. 19, Issue S6, pp. A1265-A1271 (2011).


'/>"/>

Contact: Angela Stark
astark@osa.org
202-416-1443
Optical Society of America
Source:Eurekalert

Related biology technology :

1. Nano Gold Rush: Researchers use tiny gold particles to boost organic solar cell efficiency
2. Nanowire-based sensors offer improved detection of volatile organic compounds
3. Organic Oregano Oil Gaining Popularity in Natural Health Field, According to Global Healing Center
4. Device proves solar cell potential of high bandgap inorganic nanowire arrays
5. Lab-on-a-Chip - ICAP Ocean Tomo Announces Auction of Patents for Advanced Techniques in Bio-Organic Analysis and Synthesis
6. USDAs Decision Thursday on Genetically Engineered Alfalfa -- Leahy and DeFazio Warn About USDA Decision Lifting All Protections for Organic and Conventional Farmers
7. Research team assesses environmental impact of organic solar cells
8. CRAiLAR® Organic Fibers is Approved for Global Organic Textile Standard Chemical Input Certification
9. Sermo Announces New Client Center with Advanced Mining and Monitoring of Organic Physician Dialog
10. Organic nanoelectronics a step closer
11. Reaction Progress Kinetic Analysis to Study Organic Reactions: Free On-Demand Online Seminar
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:2/10/2016)... , Feb. 10, 2016 NX Prenatal ... its proprietary NeXosome® technology for early warning of ... its most recent study by Dr. Thomas ... the Society for Maternal Fetal Medicine,s (SMFM) annual meeting ... 1-6 th , 2016.  The presentation reported initial ...
(Date:2/10/2016)... 10, 2016  Matchbook, Inc., a company specializing ... biotech companies, announced today the appointment of ... Jim brings nearly 25 years of experience in ... spent nearly two decades in executive level roles ... at Genzyme and, most recently headed global logistics ...
(Date:2/10/2016)... ... February 10, 2016 , ... PatientCrossroads announces that ... secure online PatientCrossroads platform, has exceeded both its one-year and overall recruitment goals ... study, which seeks to advance understanding of the hereditary risks for certain kinds ...
(Date:2/9/2016)... ... February 09, 2016 , ... With a presidential election in ... Care Business Conference will bring together over 500 top healthcare leaders for a night ... transformation. The conference, organized by MBA students of the University of Pennsylvania’s Wharton School, ...
Breaking Biology Technology:
(Date:2/3/2016)... , Feb. 3, 2016 ... the addition of the "Emotion Detection ... Machine Learning, and Others), Software Tools (Facial ... Areas, End Users,and Regions - Global forecast ... --> http://www.researchandmarkets.com/research/d8zjcd/emotion_detection ) has ...
(Date:2/2/2016)... Va. , Feb. 2, 2016   ... award from the U.S. Army Research Office and ... the range and sensitivity of the company,s ... Past Accounting Mission and, more generally, defense-related DNA ... DNA phenotyping capabilities (predicting appearance and ancestry from ...
(Date:1/28/2016)... 2016 Synaptics (NASDAQ: SYNA ), a leading developer ... quarter ended December 31, 2015. --> ... 2016 increased 2 percent compared to the comparable quarter last year ... 2016 was $35.0 million, or $0.93 per diluted share. ... the first quarter of fiscal 2016 grew 9 percent over the ...
Breaking Biology News(10 mins):