The accuracy and calibration objectives have been achieved. A solution for accommodating head motion is under development. For disabled people operating computers, it is appropriate to sense the eye unobtrusively, with remotely mounted cameras. In 1988, LC Technologies completed development of the first Eyegaze Computer System designed for use by people with severe motor disabilities. Eyegaze is a PC-based system, requiring only the control of one eye.
Nothing is attached to the user.
As illustrated in Figure 1, a video camera located below the computer screen continually observes the user's eye, and specialized image-processing software determines the eye orientation and projects the subject's gazepoint on the computer display. The system also generates information regarding pupil diameter, blinking, and eye fixations, useful for other eyetracking applications. The computer calculates the person's gazepoint, i.e. the coordinates of where on the display he is looking, based on the relative positions of the pupil center and corneal reflection within the video image of the eye. LED-illuminated eye image showing bright pupil. Small spot of light directly below the pupil is the corneal reflection.