Innovative lighting
In response to a UK government call to develop more energy-efficient lighting solutions, a consortium of experts has found an answer. Light Emitting Diodes (LEDs) have a very long life, consume less energy, their components don’t pose any hazard to the environment and, thanks to the collaboration of Dr Faiz Rahman and his colleagues, have become significantly brighter and easier to produce. The project is being developed in conjunction with the Institute of Photonics, University of Strathclyde, Mesophotonics Ltd and Sharp Laboratories of Europe.

LEDs are already present in electronics, from computers to LCD TVs, but until now their construction has meant that much of the light emitted was trapped in their structure. Applying a process called ‘nano-imprint lithography’ to imprint a finer pattern of holes on the LED’s surface, addresses this problem more efficiently and at a lower cost than previous methods.

Low cost
Based at the state-of-the-art nanotechnology facilities at the University of Glasgow, Dr Faiz Rahman, technical lead on the project says, ‘the challenges involved were to get a pattern of holes that was just the right shape and size over a very large piece of wafer and to do it quickly enough so that a large number could be processed in a short period to make them commercial.’

He continues, ‘nano-imprint lithography is good for relatively low cost operation and also the speed at which you can do things. There are economic advantages when it comes to the commercial production of components like photonic crystals, like the Light Emitting Diodes.’

Viable alternative
Rahman expects that a domestic LED could be available within a few years. They have other advantages over energy efficient bulbs because LEDs have no parts to burn out, their surface area is smaller and their materials are so small and chemically-bound that they pose no toxic danger to the environment.

‘We've demonstrated the technology, we know that it works,’ says Rahman. ‘What we have not done is to demonstrate a completely integrated process that could be sold to a company that could take production from A to Z and have a complete product. We should be able to complete that part of the project in about a year's time from now.’ LEDs will light the way.