Accurate gaze direction measurements with free head movement for strabismus angle estimation.

We present the Delft Assessment Instrument for Strabismus in Young children (DAISY) a device designed to measure angles of strabismus in young children fast and accurately. DAISY allows for unrestrained head movements by the mean of a triple camera vision system that simultaneously estimates the head rotation and the eye pose. The device combines two different methods to record bilateral eye position: corneal reflections (Purkinje images) and pupillary images.