!!! Press Release !!! Compound Semiconductors: unrivaled by polymers Bright polymers and organic materials with opto-electronic characteristics are the focus of numerous research projects. Again and again, the relevant reports implicate the prospect of deploying these materials in monitor or display technology - an extremely move which would be in direct competition to the current extensive use of compound semiconductor light emitting diodes (LEDs) comprising compound semiconductors. However, careful study of the published data demonstrates that bright polymers pose no competitive threat at all to compound semiconductors. The superiority of the compound semiconductor LED is clear to everyone - it has strong illuminating power at low energy consumption, long life and is economical - and it already has numerous practical applications: LEDs are used in vehicle brake lights and in other signaling equipment - the latest example being in the new S-Class model from Daimler-Benz - as well as in traffic lights, street lighting, in large public display boards and monitors in stadia, plus in outdoor advertising hoardings, which are still able to produce a strikingly clear picture even in the strongest sunlight, thanks to their ultrabright LEDs. Compound semiconductors possess some unrivaled performance characteristics vis a vis bright polymers - the corresponding information is generally available, both on the Internet and in various publications. Advantage: lifespan The useful life of compound semiconductor LEDs already runs to far in excess of 100,000 hours (more than 10 years). Bright polymers last for just 5,000 hours (208 days), although their lifespan might reasonably be expected to double to 10,000 hours in around 5 years' time. Bright polymers, in their final applications are - in contrast to compound semiconductors - very sensitive to oxygen in the air and to warmth, and are therefore more expensive to maintain. Advantage: contact In contrast to compound semiconductor LED the problem of obtaining a reliable electrical contact using bright polymers has not yet been satisfactorily addressed. In addition polymers require electrical voltages around 2-3 times higher than those of compound semiconductors. Advantage: brightness Compound semiconductors produce an intensity of brightness of up to three magnitudes higher than bright polymers!!! As a direct comparison, using a LED chip size with a typical surface area of 0.25 mm x 0.25 mm, compound semiconductors illuminate to a level of 30 mcd to 60 mcd, while the weak luminescence of a polymer is only between 0.05 and 1.3. This means the illumination of the compound semiconductor LED is 6000 per cent higher. Advantage: colours While compound semiconductors allow the production of all colors to great intensity, and the latest developments are employed to produce the greatest number of colors using less material, polymers can produce certain colors only to very unsatisfactory illumination levels. For further information please contact:
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