industry  LEDs


Osram issues a red alert for solid-state lighting


Breaking the 200 lm/W barrier for the red LED will do far more than simply increase the efficiency of car brake lights. It will also improve the efficacy and colour quality of solid-state lighting sources as well as pico-projectors and yield a lighting product for greenhouses when combined with blue LEDs, says Martin Behringer from Osram Opto Semiconductors.


T


he term ‘solid-state lighting’ conjures up images of white emission emanating from streetlights, car headlamps and modern fixtures in subway stations. Anyone standing there and basking in such light will undoubtedly look on in awe at these diminutive illumination sources, but that does not mean that they will be thankful for their pale-looking faces produce by the collections of white-emitting LEDs.


Fortunately, we don’t live in a black and white world – we live in one of colour and warm faces. But to do justice to the world’s incredibly rich palette requires an illumination source that produces the full gamut of colours, from the deepest reds right through to blues and violets.


The traditional white LEDs that combine a blue-emitting chip with a yellow phosphor fail in this regard, because they ignore longer wavelengths. Although long- wavelength sources – directly emitting red, yellow and


20 www.compoundsemiconductor.net March 2012


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