Optoelectronics Group

The optoelectronics laboratory was established in 1987 and occupies approximately 25m2. It offers the usual specialised optoelectronics equipment such as optical benches, mounts, translation stages, lens holders and other similar equipment. It can support both undergraduate final year projects and postgraduate research in the areas of electro-optic modulation, line of sight laser communications and fibre optic communications.

Additionally, there are specialised facilities for both undergraduate and postgraduate work in the area of Plastic Optical Fibres (POF) in data communications and sensors. These facilities in POF also started in 1987 and were one of the first in a UK institution.

London Met has offered use of the POF facilities, for extended periods, to visiting European researchers and other UK university collaborators. These facilities are also being used for consultancy and industrial research contracts and this is an area of activity the group endeavours to expand.

Typical undergraduate Plastic Optical Fibre (POF) project areas:

  • short data links (RS232C full-duplex, over one or more fibres)
  • video links
  • LAN components (splitters, 1x 8 couplers, mode scramblers)
  • sensing techniques

Evolved research areas using POF:

  • POF LAN and components
    We have developed simple 'do-it-yourself' versions of 1 x 2, 1 x N and N x N couplers based on butting of polished fibre ends using mechanical parts that can be produced inexpensively with appropriate polymer mould design techniques. Excess loss, though dependent on fibre polish finish, is consistently less than 3 dB, making these couplers useful in many applications.

  • POF data links and bandwidth optimisation
    Currently, we investigate ways for improving the bandwidth performance of high numerical aperture (NA) POF using mode scrambling / filtering techniques. We have developed a 'small size' moulded scrambler for easy use in data links and sensors. Additional advantages in using mode scrambling techniques in POF links relate to improvements in link reliability and repeatability.

  • POF sensors
    An optical displacement sensor has been developed which utilizes three Plastic Optical Fibres. It is an extrinsic, intensity based, differential technique. The sensor has linear response and scalable range. It has a dynamic range of 45mm (20mm < R < 65mm) when operated with ambient illumination, accuracy of one per cent, and good temperature stability. It has been shown that the sensor can be adopted to measure dynamic variables such as vibration, pressure, etc.

The group's work has often been presented at the annual international POF conferences, such as in the UK, USA, France, Germany, Japan, China, Brazil and Greece. Additionally, tutorials and one-day short courses on POF Data Communications and POF Sensors have also been presented in Portugal, USA, UK, France and Germany.

The Group wishes to continue its activities with POF and is very interested in expanding both its academic and industrial partnerships.

For further information, please contact Professor B Virdee b.virdee@londonmet.ac.uk

For more details see Centre for Communications Technology.