Extracting Corneal Reflection of Screen by High-Speed Control of Polarization

Polarization has been considered to be a reference instead of near-infrared light sources in eye tracking because the light emitted from a liquid-crystal display is typically polarized. However, the degree of polarization depends on the display content. Thus, devising a novel method is crucial for stably extracting the display reflection from the corneal surface. Therefore, we propose an eye-tracking method that inserts a white background between the display contents using a high-speed display to extract the screen reflection on the cornea. A high-speed camera and polarization modulator are integrated to extract the polarized light emitted from a high-speed display, and then the point-of-gaze is estimated. We evaluated the accuracy of the estimated point-of-gaze under several conditions to compare the proposed method with conventional approaches. The results revealed that the proposed method improved eye gaze estimation.