New Form of Optical Fibre for Laser Light Conversion
Pure glass optical fibres have been invented which have a remarkable property for converting laser light to a broadband supercontinuum.
PhD student Jim Stone, working with Professor Jonathan Knight and Dr Dmitry Skryabin at the Centre for Photonics & Photonic Materials (CPPM) in the Department of Physics, invented a new form of optical fibre for converting laser light to a broadband supercontinuum. They have developed pure glass optical fibres which have a remarkable property. When single-colour laser light is put into one end, it gets transformed into white light as it propagates. It leaves the fibre at the far end consisting of a very broad range of colours, yet with the same property of brightness as when it entered. Supercontinuum light sources based on fibre lasers are a fledgling technology, estimated to be worth $15 million in 2008/2009.
“This white light source is called an optical supercontinuum," says Professor Jonathan Knight. "It’s like a laser but contains a broad range of different wavelengths or colours. The transformation of the light is really impressive because the fibres are only made of glass and air. It’s as if light changed colour just because it passed through a transparent glass window.
“We used an advance in our understanding to design a fibre which generates more blue light than those which we had previously studied. We then fabricated the new fibre in our optical fibre fabrication facility. We demonstrated its improved capability to generate blue light by passing a laser through it. This advance is important because blue light interacts more strongly with many materials than other colours. The newly-improved light source thus promises to enable and simplify several techniques of biological and bio-medical analysis."
The researchers have teamed up with Fianium, a market-leading UK-based commercial supplier of fibre laser systems and supercontinuum sources. They have incorporated the improved fibre into a new product line, under an intellectual property licensing arrangement with the University of Bath.
“This new product has proven extremely popular, attracting wide interest from across the globe," adds Professor Knight. "Our continuing research in this area is focused on more efficient conversion of light to a wide range of colours using smaller laser sources.”
One of the objectives of research within the CPPM is to use optical fibres to create a new generation of light sources. These sources are already enabling new applications, especially in healthcare and the biological sciences, and we are working with partners in the commercial sector both from the UK and within the EU to bring our new science rapidly to the marketplace.