IEO's key research areas :
IEO has developed a range of photosensitive materials that change refractive index, with very high resolution (several thousand lines/mm)
• Improved the refractive index modulation making brighter holograms and more efficient devices.• Improved the resolution allowing for smaller features making reflection holograms possible, visible in normal room light.
• Increased range of the materials now available so that we now have holograms and devices that are pressuresensitive, humidity sensitive, humidity resistant, laminatable, printable and flexible.
Optical setups for holography and interference:
IEO has developed a range of holographic techniques that enable the creation and recording of high spatial frequency optical interference patterns. These techniques are used to test photosensitive materials and create diffractive devices (see Main applications). The use of CMOS cameras and appropriate software enable small changes in the displacement of surfaces to be measured.
Key achievements :
Development of holographic lenses made from thin photopolymer layers - by adjusting the spatial frequencies and combining elements we have improved the acceptance angle of these lenses (usually low in diffractive devices).
• Construction of interferometric systems to measure vibrations of very low amplitude.
• Fabrication of efficient diffractive devices which are used to change the direction of light beams.
Specialized printing for optical devices:
IEO has developed methods that allow optical materials to be selectively patterned by a printing process as well as an optical/light exposure process. The same technique can be used to deposit nanoparticles which add functionality such as sensing, or to produce photonic effects
• Proof of concept for a new production process for individualized security holograms. IP successfully licensed.
• Successful printing of nanoparticles of various types on a range of substrates including photopolymer.
• Development of printed diffractive devices (with a minimum feature size 10 -15 microns).
Medical Ultrasound Physics and Technology sub group:
The Medical Ultrasound Physics and Technology group is part of the IEO centre. It has developed novel tissue mimicking materials for use in quality assurance and clinical training test devices for medical ultrasound. These test devices have also been used to characterise new ultrasound technology such as contrast agent imaging as well as emerging imaging techniques such as microwave imaging.
• Proof of concept for a new production process for anatomically realistic clinical training test devices, such as breast and renal arteries. The anatomical breast test device is currently being investigated for its commercial potential.
• Proof of concept of new clinical training and competency procedure for trainee breast ultrasound registrars. IP successfully licensed.
• Development of a range of novel test devices for evaluating the capability of medical ultrasound imaging and Doppler techniques.
Applications for these technologies include sensing for packaging, light focussing and re-direction with thin polymer optics, vibration and surface measurement and product security and traceability as well as quality assurance and medical ultrasound imaging training and assessment.