CD Laboratory for Laser Development and their Application in Medicine II

Laser light sources that enable ultrashort light pulses are being researched and further developed for use in special imaging procedures. The focus is on their application for measuring the human tear film and the cornea as well as their combination with other measuring methods.

Optical coherence tomography (OCT) is an optical procedure that can measure biological tissue through a transparent surface without touching it. OCT is frequently used in ophthalmology, e.g. to examine the back of the eye through the vitreous body. The functional principle of OCT is based on measuring the intensity and time delay of light reflected by the tissue. A laser is used as the light source.

Research is being conducted into the development of special lasers that combine the higher performance of OCT with a more compact design and a more favourable price. This is based on titanium-sapphire laser technology, which allows ultra-short laser pulses of less than seven femtoseconds. At the same time, titanium-sapphire lasers can be tuned over a wide wavelength range, i.e. the wavelength of the light they emit can be changed over this range.

Based on this laser technology, the performance of OCT is being further developed. This enables resolutions of less than one micrometre at up to 200,000 measurements per second. This means that the tear film and cornea of the human eye can also be measured. It will also be possible to analyse the effectiveness of new eye drops for treating extremely dry eyes.

Research is also being carried out to expand the range of applications of OCT by combining it with other measurement methods. For example, molecular and functional measurements are possible through combinations with so-called Coherent Anti-Stokes Raman Scattering and Doppler OCT.

Overall, the research aims to make the use of OCT more practicable and to utilise it for further applications.