Solid state lighting is quickly becoming recognised as the only new alternative to traditional forms of artificial light. The industry builds upon the electronics and opto electronics industry, creating artificial light in a completely different way to what we have all been used to.

Energy is converted to visible light by a flow of electrons through a solid mass, silicon in origin. This is a completely different principle to what we have all experienced in our lives under artificial light.

Recent technology advances have enabled the production of extremely high brightness LEDs, which when arrayed in groups provide a suitable alternative to traditional sources of light, which require more energy to run by comparison.

Light emitting diodes (LEDs) come in numerous shapes and forms. From extremely cheap novelty low brightness types, to the highest quality laser diodes, LEDs have evolved since they were first developed in the late 1950s.

Scientists started at one end of the spectrum, namely infra red. Whilst of little use for replacing the light bulb, early uses of infra red LEDs revolutionised remote control. Infra Red LEDs were quickly adopted into domestic televisions and subsequent appliances.

From the early advances in the UK in the late 1950s, it was simply a matter of time before scientists looked to other rare minerals in order to create visible light.

Visible spectrum LEDs have been commonplace elements used mainly for power indication. From this point to the mid 1990s red, amber and green LEDs were developed, but lacked blue, in order to produce white light. By the mid 1990s the blue LED had been invented and it was this step that led to our present position.

As with Moore's law in the computer world, the highest brightness modern LEDs reached a critical point where brightness was visibly enough to compete with other forms of artificial light. Since the introduction of blue, lumen efficiency (a measure of light output) has doubled roughly every two years.

The adoption of solid state technology seems set to continue to rise. Pioneering companies in this field are reporting production capacity doubling every year. Obvious areas of impact include all the traffic lights in the US, expected to be swapped from incandescent to LED solid state sources by the end of 2005.

Not only is there a reduction in running costs, critical lamp replacement has been eliminated, reducing maintenance. The reduction in running costs will benefit the nation and the environment, perhaps even helping the energy systems capacity?

The automotive industry across all major car manufacturers is adopting the use of LEDs rather than bulbs in cars. The first production cars are already being fitted with LEDs including headlights. Rear indicators using LEDs have been around for quite some time now.

Solid state lighting is only now coming of age and yet we seem already familiar with the technology in everyday use, however, recent technology advances are only just becoming apparent.