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About OLED
In the lighting technology world a new era is coming. Great research results on the solid state lighting sources are pushing in order to accelerate the revolution. This new lighting source class is able to make complete new solutions and applications that would not be possible with the current ones.
The OLED (Organic Light Emitting Diodes), commonly defined as Organic LED, are thin film devices with an active layer typically lower than 500nm (500 millionths of millimetre).
They have a sandwich structure and they are made by:
a specific support that could be a glass or plastic sheet;
a transparent electrode that acts as an anode. Typically they use the Indium Tin Oxides ITO because has the special combination of conducting electricity and transmitting lights;
some organic layers that are the real active light emitting materials with a global thickness of 100-200 nm;
a second electrode (cathode), that is generally a reactive metal like Barium or Calcium covered by a protective layer of aluminium or silver.
Finally the whole device is encapsulated using waterproof materials in order to protect the active layers by the water and the air. These elements could reduce the lifetime of the complete apparatus.
Applying a low voltage (around 10V) to the electrodes, there is the injection of positive charges (holes) and negative charges (electrons) from the electrons to the organic active substrate. The combination of electrons and holes, will produce photons (so light). They light goes out form the device through the transparent anode.
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Advantages
Thanks to their versatility, the solid state lighting have the potentiality to upset the current concept of light. Due to the high lighting efficiency, that is underlined by the light creation without the production of heat, these devices are characterized by a low energetic consumption that could bring invaluable saving and considerable reduction of CO2 emissions in the atmosphere. Also, the OLED is considered as a real “green” light because they don’t contain mercury so it makes them easily wasted. In the list below, you can see the comparison between the OLED and the current lighting sources using functional/operative features.
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