General software for an on-line eye-movement recording system

A general on-line eye-movement recording system is described which consists basically of (a) some on-line instrument capable of displaying a visual scene, (b) a device to measure eye position and output position information in the form of electrical signals (c) an analogue-to-digital converter, and (d) a computer. General software for such a system is discussed with emphasis on subroutines which perform calibration and which continuously monitor eye position.