© Stella Morabito ‐ ECP ‐ MSTM 2008 ‐
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March 2008
What is an OLED?
An OLED or Organic Light Emitting Diode is a light emitting device based
on the principle of electroluminescence of organic crystals.
An OLED is a solid‐state semiconductor device that is 100 to 500
nanometers thick or about 200 times smaller than a human hair.
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March 2008
OLEDs Device operation principles
By courtesy of Homer Antoniadis
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March 2008
How do OLEDs create light?
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March 2008
OLEDs structure
The two‐layer structure
Magnesium‐silver (10:1)
Lithium‐Aluminium
Polyfluorene
Polyaniline
Indium‐tin‐oxide
By courtesy of Homer Antoniadis
By courtesy of Homer Antoniadis
© Stella Morabito ‐ ECP ‐ MSTM 2008 ‐
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March 2008
OLEDs structure
The multi‐layer structure
The multi‐layer structure of OLED consists of several layers of organic
materials sequentially deposited on glass substrate, each layer having a specific
purpose that serves to enhance device quality and performance.
The schematic representation of an ideal/standard OLED device is shown
below.
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March 2008
History of OLEDs development
• In 1979 Chin Tang discovered electroluminescence in the research
department of Kodak. During his work with solar cells he observed a blue
glow of organic material.
• The technology of current OLEDs was developed by Eastman Kodak
starting in 1987 (Tang and Van Slyke)
• The first OLEDs were organic light diodes from small molecules (SM‐
OLED).
• In 1990 electroluminescence in polymers was discovered.
• Cambridge Display Technology developed OLEDs on the basis of polymers
(P‐OLED or PLED).
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March 2008
Two technological options
SM‐OLEDs and P‐OLEDs
Small Molecules = SM‐OLEDs
• Technology developed by Kodak since 1987
• Small molecules have to be deposited onto the glass by vacuum deposition expensive
• Heating necessary not all the compounds can stand heating (glass is not an option)
• Moisture and oxygen sensitivity of the compounds
• Most suitable for small screens
• Used in some cell phones made by Motorola and in car stereos made by Pioneer Electronics.
Polymer OLEDS = P‐OLEDs
• Technology developed in 1990 by Cambridge University in the United Kingdom
• Spin off into a private company: Cambridge Display Technology (CDT)
• P‐OLEDs allow the solution of organic material in liquid Production process can be spin
coating or Ink Jet printing inexpensive and easy to industrialize
• Flexible supports (plastic) possible more options than glass only
• Still lag behind SM‐OLEDs in picture quality
• The technology has been licensed to a variety of companies including Philips, Seiko Epson,
OSRAM, and Delta Electronics.
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March 2008
© Stella Morabito ‐ ECP ‐ MSTM 2008 ‐
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March 2008
Passive Matrix – PM‐OLEDS
• Strips of of cathode and strips of anode arranged in a perpendicular way
• The intersection forms the pixel where light is emitted
• External circuitry illuminates any chosen pixel in the array by driving the
appropriate row line and column line
• A video image is created by sequentially scanning through all rows and columns,
briefly switching on the pixels needed to display a particular image
• The brightness of each pixel is proportional to the amount of current applied
© Stella Morabito ‐ ECP ‐ MSTM 2008 ‐
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March 2008
Active Matrix ‐ AM‐OLEDs
• Each pixel is addressed by at least two TFT (thin‐film transistor) transistors, which
provide brightness and on‐off control by addressing the pixel in a row/column
format
• The transistor circuits retain the state (on/off) and level (intensity) information
programmed by the display electronics.
• Therefore, the light output of every pixel is controlled continuously, rather than
being "pulsed" with high currents just once per refresh cycle.
© Stella Morabito ‐ ECP ‐ MSTM 2008 ‐
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March 2008
Which uses for
PM‐OLEDs & AM‐OLEDs?
PM‐OLEDs AM‐OLEDs
• Suitable for 2‐3’’ screens • Suitable for large displays
(cellphones, PDA, MP3) (computer monitors, TVs)
• Consume more, due to the • Consume less, because TFT
power needed for external array requires less power
circuitry than external circuitry
• Easy to produce • Faster refresh rates
suitable for video
• More expensive
• Brighter and sharper images
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March 2008
OLEDs Acronyms….
TOLED
SM‐OLED
POLED PhOLED
RCOLED
SOLED
PLED
FOLED
PM‐OLED
AM ‐OLED
WOLED
© Stella Morabito ‐ ECP ‐ MSTM 2008 ‐
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March 2008
OLEDs for dummies…
AM OLED Active Matrix OLED device
FOLED Flexible OLED
OLED Organic Light Emitting Diode/Device/Display
PhOLED Phosphorescent OLED
PLED Polymer Light Emitting Diode
PM OLED Passive Matrix OLED device
P‐OLED Polymer OLED (Cambridge Display Technology)
RCOLED Resonant Cavity OLED (provides a purer color in the
forward direction along the viewing axis of the OLED)
SM‐OLED Small Molecule OLED (Kodak)
SOLED Stacked OLED
TOLED Transparent OLED
WOLED White OLED
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March 2008
OLEDs vs. LCD
• Self‐emitting light, in contrast to the required backlight for LCD
• High brightness and contrast (1.000.000 : 1, against max. 10.000 : 1)
• Lightweight and thin (less than 2 mm)
• The support can be plastic (instead of glass)
• Capable of wide viewing angles（~170°)
• Low operating voltage and power consumption
• Quick response (~ μ second level, instead of 8 msec.)
• No “trailer” effect
• Wide range of operating temperatures (‐40 to 85 )
• A simplified manufacturing process compared to LCD
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March 2008
OLEDs vs. LCDs
A simplified manufacturing process
OLEDs
LCDs
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March 2008
OLED vs. LCD
Thinner, lighter, faster, brighter
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March 2008
OLEDs are already on the market!
Philips- Norelco Sensotec Kodak's EasyShare LS633
zoom digital camera sports
an AM550L 2.2" OLED
active‐matrix display.
Kodak boasts that the
Cell phones with AM
This razor has a Polymer‐ display is so good that you
OLEDs
based OLED display don't need a PC to own
showing battery life and one! Photo: Kodak
shave‐sensitivity settings.
When switched off, it acts
as a mirror!
© Stella Morabito ‐ ECP ‐ MSTM 2008 ‐
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March 2008
OLEDs market shows strong growth
By courtesy of Homer Antoniadis
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March 2008
OLED Market 2004‐2005
Revenues 2005
USD 600 mio
Source: DisplayBank
• 2004: 37 mio units
Korea = 16 million units
Taiwan = 11 million units
Japan = 7 million units
Others = 3 million units
• 2005: 61 mio units global mkt. growth of 65%
Korea = 22 million units
Taiwan = 27 million units
Japan = 8 million units
Others = 4 million units
• Leading makers from Korea, Taiwan and Japan control over 90% of the market
• China has reached in 2005 half the production of Japan
© Stella Morabito ‐ ECP ‐ MSTM 2008 ‐
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March 2008
OLED TV Market 2006 ‐ 2013
• Sales of the first 11’’ OLED display by Sony began in December
2007 in Japan.
• The set is sold in the US since January 2008 for USD 2500
© Stella Morabito ‐ ECP ‐ MSTM 2008 ‐
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March 2008
Problems OLEDs have to overcome
• Lifetime shorter than other technologies
• Moisture and Oxygen cause major damages
• Manufacturing processes still expensive
This requires innovations in materials :
chemistry will decide about the future and the success
of the OLED technology.
© Stella Morabito ‐ ECP ‐ MSTM 2008 ‐
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March 2008
LG at CES 2007
The 2.2‐inch A220A screens boast QVGA
resolution (240 x 320) and 262,000 colors
AM‐OLED A220A screens
© Stella Morabito ‐ ECP ‐ MSTM 2008 ‐
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March 2008
Samsung at CES 2007 & 2008
Samsung's prototype 40‐inch OLED TV
at CES 2007
• Resolution : 1280 x 800
• Brightness : 600 cd/m²
• Contrast ratio : 5000 : 1
Samsung's 14‐inch prototype at CES 2008
© Stella Morabito ‐ ECP ‐ MSTM 2008 ‐
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March 2008
Samsung at CES 2008
TV sets that are a mere 3cm thick, or less
31’’ OLED
• Resolution: 1080p
• Contrast : 1.000.000 : 1
• Colour gamut: 107%
• Life expectancy : 35.000 hrs.
• Planned for 2009/2010
© Stella Morabito ‐ ECP ‐ MSTM 2008 ‐
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March 2008
Sony at CES 2008
XEL‐1 ‐ 11’’ OLED 27’’ OLED
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March 2008
Sony at CES 2008
11’’ XEL‐1 27’’
• Resolution : 960 x 540 • Resolution 1920 x 1080
• Contrast : 1.000.000 : 1 • Contrast: 1.000.000 : 1
• Thickness : 3 mm. • Thickness : 10 mm.
• Expected life‐time: 30.000 hrs. • Brightness: (peaks) 600 cd/m²
• Selling price: USD 2500 • On the market by 2009
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March 2008
OLEDs make light!
Makoto Tojiki’s “Archimedes Dream”
OLED illuminated surfaces
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March 2008
OLEDs make light!
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March 2008
Uses & advantages of lighting OLEDs
USES
• Replace conventional light bulbs
OLEDs do not get hot
They are flexible so they enable original designs
OLEDs can change colours and brightness at the press of a button
• Light emitting wall papers
• Lighting windows
• Lighting ceilings
ADVANTAGES
• Energy consumption reduction by 50%
• OLEDs do not contain mercury
• OLEDs can be disposed of like glass
© Stella Morabito ‐ ECP ‐ MSTM 2008 ‐
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March 2008
Customize your keyboard!
GAMES
• Since each key has an OLED display it is not game dependant.
Below is an image of the Optimus keyboard setup to run
Quake.
© Stella Morabito ‐ ECP ‐ MSTM 2008 ‐
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March 2008
Optimus OLED keyboard will change
keyboards forever…
LANGUAGES AND ALPHABETS
Roman QWERTY Russian
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March 2008
Customize your shortcuts
• Keyboard icons can look anything you want
• Keyboard is OS independent (open‐source keyboard)
• Optimus keyboard is still expensive (379 € in the 1 active button
configuration; 1259€ with 113 active buttons)
© Stella Morabito ‐ ECP ‐ MSTM 2008 ‐
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March 2008
You said OLED keyboard?
OLED keyboard: easier for control towers than for gamers???
© Stella Morabito ‐ ECP ‐ MSTM 2008 ‐
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March 2008
The future
Fully flexible displays Eye catching packaging with
changing information content
Customizable touchpads for
Korean mobile market
Concept watch
Paper‐thin lighting that can be
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applied to whole wall surfaces.
The future
© Stella Morabito ‐ ECP ‐ MSTM 2008 ‐
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March 2008
Bibliography
• ANTONIADIS, Homer, Overview of OLED Display Technology, OSRAM Opto Semiconductors,
http://www.ewh.ieee.org/soc/cpmt/presentations/cpmt0401a.pdf
• BYLUND, Anders, Steve Abramson is OLEDing the way, in The Motley Fool, http://www.fool.com/investing/general/2007/09/26/steve‐
abramson‐is‐oleding‐the‐way.aspx, September 26, 2006
• FELTON, Michael J., Thinner, lighter, better, brighter, in Today’s Chemist at work,
http://pubs.acs.org/subscribe/journals/tcaw/10/i11/html/11felton.html, November 2001
• FREUDENRICH, Craig, How OLEDs Work, in Howstuffworks, http://computer.howstuffworks.com/oled.htm
• HECKER, Dr. Klaus, Brochure on Organic Electronics, OE‐A, Organic Electronics Association, VDMA Verlag, 2006
• ISRAELSON, Joshua, Powering OLEDs: the care and feeding of organic displays,
http://www.edn.com/article/CA480492.html?text=OLEDs, November 2004
• SMITH, Peter, OLED Displays: Better Than Plasma Or LCD, http://www.siliconchip.com.au/cms/A_30650/printArticle.html
• TOON, John, Biasing Spin Statistics: Research Explains How to Boost the Efficiency of Polymer Organic Light‐emitting Diodes (OLEDs),
Georgia Institute of Technology, http://gtresearchnews.gatech.edu/newsrelease/oleds.htm, April 2, 2004
• Kodak’s OLEDs Tutorial, http://www.kodak.com/eknec/PageQuerier.jhtml?pq‐path=1473&pq‐locale=en_US&_requestid=4214
• Site Cambridge Display Technology: http://www.cdtltd.co.uk/
• Site OLED‐Display : http://www.oled‐display.net/
• Site OLEDomains : http://oledomains.blogspot.com/
• Site OLED‐Info : http://www.oled‐info.com/
• Site EDN Asia, Ruling the Roost : http://www.ednasia.com/article‐17749‐rulingtheroost‐Asia.html, 2005
• Site IDTechEx : OLED Lighting Has a Bright Future, http://www.idtechex.com/products/en/articles/00000551.asp
• Site Practical Home Theater Guide: The Contrast Ratio Game, http://www.practical‐home‐theater‐guide.com/contrast‐ratio.html
• Site The Science of Spectroscopy : OLED, http://scienceofspectroscopy.info/edit/index.php?title=OLED
• Site Wikipedia : http://en.wikipedia.org/
• European project OLLA, High Brightness OLEDs, site: http://www.hitech‐projects.com/euprojects/olla/
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March 2008
Little reminder of screen resolutions
VGA = Video Graphics Array (original
IBM VGA display technology, which
became a de facto industry standard in
the late 1980s
QVGA = Quarter Video Graphics Array
© Stella Morabito ‐ ECP ‐ MSTM 2008 ‐
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March 2008