This document discusses OLED technology. It begins by outlining some of the main applications of OLEDs, including in televisions and small screens due to their high reliability and readability. It then describes the basic structure of an OLED, which consists of a substrate layer, anode layer, conductive layer, emissive layer, and cathode layer. Electrons and holes combine in the emissive layer to produce light. The document notes some challenges with OLEDs, such as potential damage from water and their relatively short lifespan compared to other display technologies.

1. APPLICATIONS
STRUCTURE
WORKING
CHALLENGES

2. • OLED rganic ight mitting iode

3. APPLICATIONS
• OLED displays are mainly used in digital
devices such as high-end television
systems,and mini-screens,etc. Such types of
applications demand high reliability and
readability.
• OLEDs fit in as these consume less power
and provide high-quality display. The
current OLED technology provides
remarkable colour fidelity, high efficiency
and operation stability.

4. • OLEDS are also ecofriendly
• OLEDs are Lightweight
• OLEDs have better Power Efficiency
and Thickness
• Response Time of OLEDs is Faster

6. Substrate Layer:
This layer is a thin sheet of glass with a transparent conductive layer, which can also be made by a
clear plastic layer or foil. This substrate supports the OLED structure.
• Anode layer:
• This layer is an active layer and removes electrons. When current flows through this device,
electrons are replaced by electron holes. Thin layers are deposited onto anode surface, and
therefore, it is also known as transparent layer.
Conductive Layer:
transports the holes from the anode layer. This layer is made up of organic plastic, and the
polymers used include light-emitting polymers, polymer light-emitting diode, etc. The
conductive polymer used in OLED are polyaniline, polyethylenedioxythiophene. This layer is an
electroluminescent layer and uses the derivatives of p-phenylene vinylene and polystyrene.

7. Cathode Layer:
Cathode layer is responsible for injection of electrons when current flows through
the device. Making of this layer is done by using calcium, barium, aluminum and
magnesium. It may be either transparent or opaque depending on the type of OLED.
Emissive layer:
This layer transports electrons from anode layers.There are multiple choices of
materials and processing variables such that a wide range of wavelengths can be
emitted during emission. In this layer, two polymers are used for emitting such as
polyfluorene, poly para phenylene which normally emits green and blue lights.
This layer is made of special organic molecules that conduct electricity.

8. • As the electricity starts to flow, the cathode receives electrons from
the power source and the anode loses them
• To make an OLED light up, we simply attach a voltage
(potential difference) across the anode and cathode.
.Now we have a situation where the added electrons are making the
emissive layer negatively charged (similar to the n-type layer in a junction
diode), while the conductive layer is becoming positively charged (similar to p-
type material).

9. • Positive holes are much more mobile than negative electrons
so they jump across the boundary from the conductive layer
to the emissive layer. When a hole (a lack of electron) meets
an electron, the two things cancel out and release a brief
burst of energy in the form of a particle of light—a photon,
in other words. This process is called recombination, and
because it's happening many times a second the OLED
produces continuous light for as long as the current keeps
flowing.

12. • Easily Damaged by Water
Remember that they are organic materials. This means
that they are prone to damage caused by water, hence,
it is important that the method of sealing is improved
to ensure that the devices respond better to water.

13. .Short Lifespan
This is one of the biggest and most worrisome drawbacks to
OLEDs. A report on OLED TV panels showed that the blue
luminance degrades by 1000 hours after 1000 hours while
the red and green degrade by 7% and 8% respectively.
.Power Consumption
OLEDs are perfect for displaying an image that is
fundamentally black, consuming just 40% of the power
consumption of an LCD for the same image. However, if the
image has a white background, the power consumption will
be about 3 times more.