Ray interpolation for generic triangulation based on a galvanometric laser scanning system

Our research group is currently developing a new optical head tracking system for intracranial radiosurgery. The system uses infrared laser light to measure features of the soft tissue on the patients forehead which correlate with the thickness of the soft tissue. For future registration purposes, the system also acquires accurate pointwise reconstructions of the corresponding surface of the forehead by using triangulation. This paper proposes a method for the interpolation of laser rays based on a galvanometric laser scanning system. The advantage of the ray interpolation is that an alternative time consuming recalibration of the laser rays can be avoided. Experiments revealed a triangulation accuracy of around 0.1192 mm using ray interpolation.