ELECTROLUMINESCENCE

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ELECTROLUMINESCENCE

• EL TECHNOLOGIE
• DUNE scientific design centre

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EL TECHNOLOGIEDUNE scientific design centre

• Electroluminescence (EL) is an optical phenomenon
  and electrical phenomenon in which a material
  emits light in response to an electric current
  passed through

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EL TECHNOLOGIEDUNE scientific design centre

• Electroluminescence is the result of radiative
  recombination of electrons and holes in a
  material (usually a semiconductor). The excited
  electrons release their energy as photons - light

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EL TECHNOLOGIEDUNE scientific design centre

• Examples of electroluminescent materials
• Powder zinc sulfide doped with Copper or Silver
• Thin film zinc sulfide doped with Manganese
• Natural blue diamond (diamond with boron as a
  dopant).
• III-V semiconductors - such as InP,GaAs,and GaN.
• Inorganic semiconductors - such as
  Ru(bpy)32(PF6-)2, where bpy is 2,2'-bipyridine
• PEDOT Poly(3,4-ethylenedioxythiophene

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EL TECHNOLOGIEDUNE scientific design centre
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EL TECHNOLOGIEDUNE scientific design centre

• Recently, blue, red, and green emitting thin film
  electroluminescent materials have been developed
  that offer the potential for long life and full
  color electroluminescent displays.
• In either case, the EL material must be enclosed
  between two electrodes and at least one electrode
  must be transparent to allow the escape of the
  produced light. Glass coated with indium oxide or
  tin oxide is commonly used as the front
  (transparent) electrode while the back electrode
  is or is coated with reflective metal

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EL TECHNOLOGIEDUNE scientific design centre

• Practical implementations
• An electroluminescent nightlight in operation
  diam. 60 mm, (uses 0.08W at 230V)
• The most common EL devices are either powder or
  thin film

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EL TECHNOLOGIEDUNE scientific design centre
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EL TECHNOLOGIEDUNE scientific design centre

• The world's first electroluminescent billboard
  campaign, Canada, Winter 2005

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EL TECHNOLOGIEDUNE scientific design centre