Patent ID: 7407287

Claim:
A pupil measuring apparatus comprising: a mark moving device for moving a position of a mark in a predetermined region from a reference position, said reference position being set at a position where eyes are to be placed; an illumination optical system for illuminating said reference position; a first camera imaging said eye placed at said reference position; calculating means, on the basis of a video signal from said first camera, for performing the following steps of: setting a plurality of horizontal lines on an image pickup surface of said first camera, a video signal corresponding to each horizontal line including high, middle and low levels respectively indicating reflected lights from a white sclera, an iris and a pupil of the relevant eye, performing a binarizing operation of the video signal on the basis of a reference level to obtain a pulse where a width of the pulse indicates a width of a pupil per the horizontal line, the reference level being set between levels respectively corresponding to the reflected lights from the iris and the pupil, calculating averages of the widths per a predetermined group of the horizontal lines in a frame, determining a maximum among the calculated averages, and storing a center position of a width of the pulse yielding said maximum as a horizontal position of the pupil.