Seminar on Organic light emitting technology.

1. ORGANIC LIGHT EMITTING DIODE
TECHNOLOGY
SEMINAR-III
Presented by: Geetanjali Chettri
M. Tech (Power Electronics)
201725003
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2. CONTENTS
1. Introduction.
2. What is an OLED?
3. Structure of OLED.
4. Working principle.
5. OLED deposition.
6. OLED display.
7. OLED vs LCD
8. OLED market.
9. Advantages.
10. Disadvantages.
11. Applications.
12. Conclusion.
13. References. 2

3. INTRODUCTION
 Uses organic light emitting diode(OLED).
 Emerging Technology for displays in devices.
 Main principle behind the OLED technology is
electroluminescence.
 Offers brighter, thinner, high contrast, flexible displays.
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4. WHAT IS AN OLED?
 OLEDs are solid state devices composed of thin films of organic
molecules that is 100 to 500 nanometres thick.
 They emits light with the application of electricity.
 They doesn’t require any backlight. i.e., they are self emitting.
 They are made from carbon and hydrogen.
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5. STRUCTURE OF OLED
 Substrate(clear plastic, glass, foil):It supports the OLED.
 Anode: The anode removes electrons when a current flows through
the device.
 Organic layer :These layers are made of organic molecules or
polymers.
 Conductive layer(hole transport layer).
 Emissive layer(electron transport layer).
 Cathode: The cathode injects electrons when a current flows through
the device.
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6. Fig 1: Structure of OLED
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7. WORKING PRINCIPLE
 A voltage is applied across the anode and cathode.
 Current flows from cathode to anode through the organic
layers.
 Electrons are making the emissive layer negatively charged,
while the conductive layer is becoming positively charged.
 Holes jump into emissive layer .
 Electron and hole combine and light is emitted.
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8. 8
 The colour of the light depend on the type of organic
molecules.
 Manufacturer place several types of organic film on the
same OLEDs to make the colour display.
 The brightness of the lights depend on the amount of
current applied, more the current brighter the light.

9. Fig 2: Working principle of OLED
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10. OLED DEPOSITION
 Organic layers can be applied using the following
methods:
- Evaporation and shadow masking.
- Inkjet printing.
- Organic vapour phase deposition.
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11. EVAPORATION AND SHADOW MASKING(ESM)
In a vacuum chamber the organic molecules are gently heated and allowed to
condense as thin films onto cooled substrate. This process is expensive and
inefficient.
Fig 3: Representation of ESM
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12. ORGANIC VAPOR PHASE DEPOSITION(OVPD)
In hot-walled reactor chamber, a carrier gas transports evaporated organic
molecules onto cooled substrate, where they condense into thin films. Using a
carrier gas increases the efficiency and reduces the cost of making OLED’s.
Fig 4: Representation of OVPD
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13. INKJET PRINTING
With inkjet technology, OLED’s are sprayed onto substrates just like inks
are sprayed onto paper during printing. Inkjet technology greatly reduces
the cost of OLED’s manufacturing and allows OLED’s to be printed on
very thin films for large display like 80-inch TV screens.
Fig 5: Representation of inkjet printing
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14. OLED VS LCD
OLED LCD
 Greater viewing
angle.
 High contrast.
 Fast response time.
 No backlight ,it itself
is emitting.
 Limited view angle.
 Low contrast.
 Slow response time.
 Require backlight.
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OLED VS LCD
i
ii
iii iv

16. OLED MARKET
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Fig 8: Market growth of OLED, Yole Development

17. ADVANTAGE
 Thinner, lighter and more flexible.
 Doesn’t require backlight.
 Faster response time.
 Large fields of view, about 170 degrees.
 High resolution.
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18. DISADVANTAGES
 Expensive
 Short lifespan.
 Water damage.
 Colour balance issue.
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19. APPLICATION
 Mobile phone screen (Samsung/NEC, Motorola, LG).
 Car radio.
 Television screens.
 Digital camera (Kodak).
 Car stereo (Pioneer, TDK, Kenwood).
 Razor (Philips).
 Flexible displays
 Replacing incandescent and fluorescent light b
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Current main commercial applications
FUTURE

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Fig 9: OLED application

21. REFERENCES
1. American Journal of Engineering Research (AJER)e-ISSN: 2320-0847 p-ISSN :
2320-0936Volume-4, Issue-9,pp-153-159.
2. International Journal of Advanced Research in Computer and Communication
Engineering ISO 3297:2007 Certified Vol. 5, Issue 11, November 2016
3. Difference between LCD and OLED , accessed from www.differencebetween.net
4. "OLED Lights and Sony OLED" accessed from www.oled-info.com
5. International Journal Of Engineering And Computer Science ISSN:2319-7242
Volume1 Issue 2 Nov 2012 Page No. 75-84
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22. CONCLUSION
 Organic Light Emitting Diodes are evolving as the next
generation displays.
 As OLED display technology matures, it will be better able
to improve upon certain existing limitations of LCD
including
-high power consumption
-limited viewing angles
-poor contrast ratios
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23. THANK YOU
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