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Since their inception in the early ‘60’s, light emitting diodes (LEDs) have
gained widespread use and now can be found nearly everywhere. The devices
are created by depositing two thin layers of materials onto a substrate, one
with an excess of electrons and the other having “holes” and needing electrons
to achieve a more stable state. When a potential is applied across the
device, the electrons and holes move in the opposite directions. This
causes light to be emitted with a wavelength and color determined by the energy
released when the electrons and holes combine.
Today, special deposition techniques have made possible LEDs with much
higher brightness (HBLEDs) than traditional devices. This opens up many
new applications such as backlighting for displays, automotive lighting and new
consumer products like flash for camera phones or compact
projectors. Goals for these new HBLEDs are to have them
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Be Brighter
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Last Longer
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Cost Less
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Be Compatible with Lead-free Processing
Silicones have found use in HBLEDs for many critical needs – providing
electrical and environmental protection, increasing light-extraction,
minimizing heat build-up and forming lenses that provide options for specific
light distribution patterns and intensities. Silicone products offer good
compatibility with standard LED substrates and processing techniques. Their use
greatly improves HBLED device reliability and longevity.
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