This presentation provides an overview of organic light-emitting diode (OLED) technology. It discusses the basic structure and working mechanism of OLEDs, comparing small molecule OLEDs to polymer OLEDs. Different types of OLEDs are described, including passive matrix, active matrix, transparent, top-emitting, foldable, and white OLEDs. Fabrication techniques and a performance analysis of luminescent materials for OLED applications are reviewed. Finally, the presentation outlines the advantages and challenges of OLEDs as well as potential future applications and trends in the industry.

1. Presentation On
SEMINAr-1 (2ND Semester)
Amity School of Engineering and Technology
Amity University Uttar Pradesh
Lucknow
“PERFORMANCEANALYSISOF LUMINESCENT MATERIALS FOR OLED
APPLICATIONS: a REVIEW”
Guide: Submitted By:
Prof.(Dr.) Ashok Kumar Mishra Adrija Chowdhury
M.Tech (OEOC)
A7636913003
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2. Oled: what is it???
 Small LED displays showing only the numeric contains.
 Heavy jumbo CRTs: heavy & bulky requiring quiet larger area than
anything else; couldn’t be carried from one place to another.
 Compact LCDs: very lighter in weight; easily carried; drawback of
getting the perfect result in some particular direction.
 Lightweight, efficient and flexible display technology, based on
OLEDs emerged:
Solid-state semiconductor device
100 to 500 nm thick; 200 times smaller than a human hair.
Consists of a luminescent organic semiconducting layer sandwiched
between two electrodes and deposited on a substrate.
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3. Oled generalized structure
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 Substrate (clear plastic, glass, foil):
supports the OLED.
Anode (usually ITO): Transparent to
visible light
Cathode: metals like barium, calcium
and aluminium are used as a cathode
Organic layers: made of organic
molecules or polymers. They are of two
types:
Conducting layer - transport "holes"
from the anode. E.g: polyaniline.
Emissive layer - transport electrons
from the cathode; emits light in response
to an electric current. E.g: polyfluorene.

4. Working mechanism
The battery or power supply of
the device containing the OLED
applies a voltage across the OLED.
An electrical current flows from
the cathode to the anode through
the organic layers. (an electrical
current is a flow of electrons)
At the boundary between the
emissive and the conductive layers,
electrons find electron holes.
The OLED emits light.
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5. PERFORMANCE ANALYSIS OF LUMINESCENT
MATERIALS
Based upon the type of Organic Semiconductor
material used: SM-OLED v/s P-OLED
Based upon the type of electroluminescence
property: Fluorescence v/s Phosphorescence
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6. SM-OLED and p-oled
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7. Materials used in sm-oled
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8. Materials used in p-oled
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9. Device structure analysis: SM-OLED& P-OLED
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10. Characteristics curves analysis ofsm-oled andp-oled
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SM-OLED is better than P-OLED: in terms Of Efficiency and Lifespan; though Costlier

11. fLuorescence v/s phosphorescence
Faster decay
Durable for lesser time
period
Lesser efficient
No spin change of excitons
Emission occurs due to
singlet state excitons only
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Slower decay
Durable for longer time
period
Most efficient
Involves spin change
Both singlet and triplet
state excitons are
responsible for emission

12. characteristic curves for various parameters of oled
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13. 26 May 2014 13

14. Types of OLED
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15. Passive matrixoled
Perpendicular cathode/anode
strip orientation
Light emitted at intersection
(pixels)
External circuitry
•Turns on/off pixels
External circuitry
Large power consumption
•Used on 1-3 inch screens
•Alphanumeric display
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16. active matrix oled
Full layers of cathode,
anode, organic molecules
Thin Film Transistor
matrix (TFT) on top of anode
•Internal circuitry to
determine which pixels to
turn on/off
Less power consumed then
PMOLED
•Used for larger displays
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17. transparent oled
Transparent substrate,
cathode and anode
Bi-direction light emission
Passive or Active Matrix
OLED
Useful for heads-up display
•Transparent projector
•Screen
•glasses
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18. Top emitting oled
Non-transparent or
reflective substrate
Transparent Cathode
Used with Active Matrix
Device
Smart card displays
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19. foldable oled
Flexible metallic foil or
plastic substrate
Lightweight and durable
Reduce display breaking
Clothing OLED
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20. white oled
Emits bright white
light
Replace fluorescent
lights
Reduce energy cost for
lighting
True Color Qualities
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21. Fabricationtechnologies
 Polymer-based OLEDs: excellent film forming properties; ease of
application over large surfaces through simple, economically viable
coating techniques. e.g-ink jet printing. Small molecule materials:
typically coated as thin films via vacuum-deposition which is
difficult over large areas and is not as cost effective.
 The techniques are as follows:
 Vacuum deposition or vacuum thermal evaporation (VTE)
 Organic vapor phase deposition (OVPD)
 Inkjet printing
 Transfer-printing
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22. Pros and cons
 Much faster response
 Consume significantly
less power
 Wider viewing angles
 Thinner display
 Better contrast ratio
 Safer for the environment
 Light weight
 Cost efficient
 Brighter
 Lifetime: usage gets
limited due to
degradation of materials
 Expensive manufacturing
technologies
 Susceptible to water
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23. applications
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24. Current trend and conclusion
Manufacturers focusing on finding a cheap way to
produce: “Roll-to-Roll Manufacturing”
Increasing efficiency by: implementing multilayered
structure; boosting lifespan
OLED will replace current LED and LCD technologies
based market
Flexibility and thinness will enable many applications:
may lead to future application: heads-up displays,
automotive dashboards, billboard type displays, home and
office lightings and flexible displays
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25. references
www.google.com
www.wikipedia.com
www.electronics.howstuffworks.com
www.oled-info.com
www.oled-display.net
http://www.cepro.com/article/study_future_bright_for_ole
d_lighting_market/
http://www.technologyreview.com/energy/21116/page1/
http://optics.org/cws/article/industry/37032
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26. THANK YOU
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