A line imaging system for measurement of eyelid movements

A line scan imaging system which provides a facility for comprehensive measurement and analysis of eyelid motion in human subjects is described. The device obtains parasagittal line images of the eye and eyelids by focusing an image of the eye onto a linear 256-element CCD array. Line images are acquired and digitized at a rate of 200 per second and stored in a buffer memory. The stored data are subsequently analysed on a PC to give measurements of eyelid displacement and velocity. Measurements of eyelid displacement and velocity during normal blinks in five subjects were comparable with published results from other measurement techniques.