This thesis has developed and evaluated a novel calibration procedure for an eye tracker. The development phase has included programming and integration with the existing application programming interfaces. The evaluation phase included reliability and validity testing, as well as statistical analysis in terms of repeatability, objectivity, comprehension, relevance, and independence of the performance of the Tobii T60/T120 Eye Tracker on healthy subjects. The experimental results have shown that the prototype application gives the expected benefits in a clinical setting. A conclusion...