LED technology was first introduced in 1962, beginning with a low-intensity red light. Semiconductor-based diodes or valves produce light from the excitation of electrons as they are moved over a "light" bridge by a direct electrical current. LEDs differ from traditional incandescent light bulbs, which produce their light from heat generation.

Over the years, white LEDs have been developed by combining chips that produce different colours into a single package, or by adding a yellow phosphor layer. Improvements in light intensity and cost reductions are now resulting in wider adoption of LEDs.