Samenvatting

Optical Coherence Tomography (OCT) is an imaging technique for collecting depth resolved information in human tissue based on an interferometer.
With an imaging depth of between 1 and 2 mm, OCT is only used to investigate (near) surfaces. But with an axial (depth) resolution of between 2 and 10 μm, and a lateral (sideways) resolution between 1 and 100 μm [1][2]the images have a greater resolution than for example a MRI image [3]. In ophthalmology OCT has become a standard tool for non-invasive imaging of the retina and to detect abnormalities or monitor the progress of diseases or treatments.
In order to improve the setup's resolution and lower the costs, an investigation is started at the Academic Medical Centre in Amsterdam, and a complete new OCT setup is built. To deflect the light in order to scan over an area, a duo-galvanometer is used. Also a spectrometer is used to perform measurements. A computer program is written to control the galvanometers and communicate with the spectrometer with the right timing. This is done in National Instruments Labview.
When choosing the motion of the mirrors of the galvanometer, it must be kept in mind that mechanical stress as a result of large acceleration can damage the mirrors. Also a constant scanning speed is desired when the measurements are performed. Therefore, a path with gradual velocity changes is chosen, based on parabolas, with linear sections for the measurements.
Before the mirrors start scanning, the program checks whether the chosen settings can result in a path that exceeds the galvanometers capabilities. The program will only start the scanning if this doesn't cause damage to the mirrors.
The Labview program is written, resulting in a flexible way to control galvanometers.
A user can insert the lateral resolution of the setup, the maximum allowed acceleration of the galvanometers, the borders between which the measurements need to take place and the time between two sequential points of the path.
Future research could improve the communication between the soft- and hardware, and investigate the limits of the capabilities of the galvanometer.