Totally Free Head Motion - This new technology solves eyetracking's tolerance-to-head-motion challenge once and for all. The Eyegaze System's Eyefollower™ accommodates all natural head motions during normal computer operation. The user can sit back, sit up, slouch down, move side to side, reach over to the mouse, operate the keyboard, and move close to the screen to examine a display at close range. Automatic Eye Acquisition - The Eyefollower™ automatically acquires the eyes when the user enters the workspace, and it rapidly re-acquires the eyes when he returns his attention to the screen after turning his head away. Binocular Eyetracking - The Eyefollower™ tracks both eyes over the full range of head motion. The gazepoint sampling rate is 120 Hz. High Gazepoint Tracking Accuracy - The Eyegaze System achieves its highly accurate 0.45 degree gazepoint tracking accuracy throughout the operational head range. Easy User Calibration - The user calibration employs the same, easy procedure used with the fixed-camera Eyegaze System. Eyefollower™ Specifications:   Head Motion Volume: Side to side Up and down Back and forth 20 inches 12 inches 15 inches (51 cm) (30 cm) (38 cm)   Head Speed:   8 inches/sec (20 cm/sec)   Head Accelerations:   20 inches/sec-sq (50 cm/sec-sq)