Bright lights

COMMERCIAL PROFILE, SCIENCE FOUNDATION IRELAND:This is set to be the century of the photonics revolution and the effects will reach into every aspect of people's lives, says Prof Chris Dainty of NUI Galway

IT HAS BEEN said that the last century was the age of the electron and that the 21st century will be the age of the photon – a photon being a light particle and the fundamental component of optics and the rapidly developing science of photonics. Just as the electronics revolution transformed lives and economies in the 20th century, the photonics revolution is set to have a profound impact on almost every aspect of our lives and a research group in NUI Galway is at the very forefront of this revolution.

Headed by Prof Chris Dainty, the Applied Optics Group was formed in October 2002 with the support of Science Foundation Ireland (SFI). Together with the National Centre for Laser Applications it forms Lighthouse: The Centre for Applied Photonics.

The group’s research programme covers a wide variety of topics in applied optics and imaging science, including smart optics, adaptive optics, optical scattering and propagation and engineering optics.

And it is difficult to overstate the importance of this research. Without light, and optics, there would be no life on earth. Optics underpins solar cell technology, lighting and displays, as well as medical techniques and communications. It is expected that optics, which is also sometimes called photonics, will surpass electronics in the 21st century in terms of the size of the industry reliant on it.

From powering the internet, through the fibre-optic communications cables which will eventually go to every home, to better lighting systems, to advanced new techniques for laser surgery, optics will become ever more central to our lives.

“Optics can be applied to a wide range of different problems and we have a very diverse portfolio of research projects ongoing at present,” explains Dainty. “Photons have many advantages over electrons and optics is an enabling technology for many applications including semiconductor manufacturing, the internet, solar energy, lighting, lasers in manufacturing and surgery, optical storage (such as CDs and DVDs), cameras and mobile phones. We just wouldn’t have the broadband internet without optics.”

The semiconductor industry is another which possibly wouldn’t exist without the science of photonics. “Semiconductors are manufactured using an optical lithography process. So precise are the lenses used for the process that they cost more than €740,000 each. It’s a very broad area and in our little group we try to capture the essence of that broadness,” he says.

One of those areas is human vision. The group is involved in a collaborative project with leading intra-ocular lens manufacturer Alcon Ireland to check the merits of intra-ocular lenses before they are replaced in a cataract operation (these lenses are the plastic replacement lenses used in cataract operations).

People having cataract surgery can potentially attain better eyesight than they ever had, even in their youth, and it can leave them not requiring glasses any more. It is the world’s most common surgical procedure, with 14 million operations performed each year, and Ireland will see the numbers of procedures grow as the population ages in the coming years.

The Galway team has built a machine – one of only a handful in the world – called an Adaptive Optics Visual Simulator. This can assess the potential impact of several lenses on a person before they have eye surgery. The patient can sit at the machine and say whether they see better or worse with certain synthetic lenses. This means that when a lens is actually inserted in the patient’s eye, there is a greater confidence that it will improve sight.

This machine is important for companies that wish to test out new lenses designed for use in eye surgery. In the past, trials would have to be done with new lenses using real people. These are expensive, and raise ethical considerations as there are risks to people involved in the trial. With the Adaptive Optics Simulator, field trials are only done at the end of the process, when the capability of a lens has already been rigorously tested.

“This is a huge advantage to everyone,” says Dainty. “No field trials are required and new designs of lenses can be tested optically without any danger to patients. Adaptive optics can also be used in the diagnosis of retinal disease. As a general rule in medicine the earlier the diagnosis the better and by using adaptive optics we can see the fine detail at about the molecular level and this will certainly help with early detection.”

Another area of research for the team is astronomy. A very significant development happening in European astronomy is the construction of the European Extremely Large Telescope, or E-ELT. This is provisionally scheduled to be a 42 metre diameter giant telescope, the biggest in the world, costing €900 million, and placed probably in Chile or Antarctica.

Dainty and a colleague in the NUIG Applied Optics Group, Dr Alexander Goncharov, were the only Ireland-based scientists asked to join the initial concept design team of 50 people. Dainty worked on the adaptive optics side, while Dr Goncharov worked on the optical design aspects of the project.

The E-ELT will look at fainter and smaller objects in the sky at a better resolution: 20 times finer, smaller and better even than any space-based telescope in existence. That’s where the Applied Optics Group comes in. Images picked up by such a sensitive telescope can be subject to distortion due to a phenomenon known as atmospheric turbulence.

A system developed by the group with an adaptive mirror and other smart technology at its core takes the distorted image and transforms it into a pristine high resolution image.

These and other projects like them are just the beginning when it comes to the potential of photonics. “This year is the 50th anniversary of the invention of the laser and photonics is really only coming into its own now,” says Dainty. “The 2010 Nobel Prize for physics was shared by three people, all from the optics field. One was the person who pointed out the use that fibre-optics could have in communications and the other two were the people responsible for the invention of the charged couple device (CCD) – the technology responsible for digital photography. Furthermore, the European Commission has identified photonics as one of five key enabling technologies for the future; it’s going to be a bigger market than microelectronics.” Looking to the future he foresees breakthroughs in areas such as solar energy, display systems and lighting. One particularly exciting development could transform the way we light our homes.

“Organic light emitting diodes (OLED) is a very interesting area,” says Dainty. “This will involve using a sophisticated paint roller to paint a structure onto a wall. By connecting this structure to a power source it will light up the wall.”

But he sees the Applied Optics Group as more than just about developing new applications and seeking breakthroughs. “Possibly the most important function of the group is to train and educate young people in this branch of physics. It is people that do the research and Ireland needs as many people in this field as it can get. We have just had our 53rd PhD student graduate from the group and our goal is to get as many people as possible to become independent researchers. Sometimes with all of the research work whizzing by you can forget the importance of people.”