Quick Glance estimates the mouse point and detects mouse
events using eye images obtained by a video camera. The
calibration method is simple, but it should be recalibrated
whenever the camera position is changed [14]. Because eye
images generally have low resolution, the spatial resolution is
low. While Quick Glance is expensive, it is the most suitable
method by which users with severe disabilities who cannot
move their body and head can use computer input devices.