FOR THE last 125 years we have been able to shine light whenever and wherever we need it by simply flipping a switch. This revolution started when Thomas Edison developed the first commercial electric light bulb in 1879, and very little has changed since. The reason for this is partly because new technologies have all followed the same old paradigm: fragile, gas-filled glass envelopes with metal end-caps that produce an orb of steady, white light. However, this may soon change with the dawn of the second lighting revolution: solid-state lighting.
Unlike existing incandescent sources, which provide light that is static in space and time, solid-state sources can produce light that changes in colour, intensity and distribution, based on lighting needs and time. This could allow us, for example, to illuminate and decorate our living spaces with glowing walls and ceilings, avoiding the need for intrusive light fixtures. Furthermore, solid-state lighting consumes 50% less energy than traditional sources,while also reducing environmental waste and pollution.
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