LED - The lamp of the future?

 Many people will miss the good old electric bulb when - according to the decision of the EU - it will no longer be available on the shelves, as of 2012. The little electricity guzzlers only transform 10% of the energy into light and 90% into heat. Energy-saving lamps, however, exploit four or five times more light. But they are environmentally friendly only to a limited degree: The mercury in their interior turns it into hazardous waste after its burning up, which has to be disposed of in a time-consuming procedure and pollutes the environment. However, a potential alternative is already available: Lamps on the basis of LED. They are not only energy-saving, but manufacturers predict extremely long service lives, of presumably 20 to 25 years (the shelf live of the electronic components of the lamp, however, are not being taken into account here). Moreover, they do not contain any toxic parts and offer lighting in practically any desired colour. Only its price - about 60 euros per lamp - is very high. Besides appealing interior decoration, its application especially in the medical area, e.g. in operating theatres of hospitals, is of interest. But how good are these LED lamps actually? To examine this question, Armin Sperling, Matthias Lindemann and Marco López of the Physikalisch-Technische Bundesanstalt (PTB) have developed new equipment. It can be used to examine whether the properties of the lamps remain stable over a longer period, or whether and how signs of ageing occur. The conference on "LED-Beleuchtungstechnologien: Aktuelle Möglichkeiten und Grenzen"(LED lighting technologies: Current possibilities and limits) provides more profound information on applications and capabilities of LEDs. It will be held at the Haus der Wissenschaft ("House of Science") and at PTB in Braunschweig on June 1, 2010.