Study of remote saccade detection technique based on retroreflective features of the retina

We have been studied on an information display based on saccadic eye movements. The display can present 2D images using only a single line of flickering light sources. When people make a saccade across the light sources, they can perceive 2D images thanks to the retinal afterimage drawn by the saccade. Though, so far, saccades of observers are induced by other stimuli such as two sequentially flashing light sources, if the saccades are remotely detected, practical applications can be realized. In this study, we present a new technique for detecting saccades, based on the fast, robust pupil detection method. The method uses two infrared light sources synchronized with the camera\u27s frame rate. The two light sources generate bright and dark pupil images, and we can carve out the position of the pupil by subtracting them. From the series of the captured image, change of the eye gaze is measured as the displacement of the pupil\u27s position. Measuring the displacement with a line scanning camera, which can take one line image with high frequency, the saccade can be detected. We investigated the feasibility of this technique by clarifying the retroreflective features of the retina and required spatial resolution for detecting saccadic eye movements