Patent ID: 6035054
Filing Date: 2000-03-07
Classification: G03B

Abstract:
An apparatus comprising:light receiving means for receiving an image of an observer's eye and for outputting photoelectric conversion signals;read-out means for reading out photoelectric conversion signals from a read-out area of said light receiving means in a first read out step and in a second read out step, said read out means including means for changing photoelectric conversion signals into digital signals;limitation means for limiting the read-out area of said light receiving means, said limitation means determining a position of a pupil in the image of the observer's eye based on digital signals read out by said read-out means in a first read-out step, to limit the read-out area of said light-receiving means in a second read-out step to within an area smaller than the entire read-out area, said smaller area corresponding to an area lying around a center of the pupil, such that said read-out means changes the photoelectric conversion signals from the entire read-out area into digital signals in the first read-out step, and changes only photoelectric conversion signals from said smaller area to digital signals in the second read-out step; andinformation processing means for extracting characteristic information including a plurality of characteristics on the basis of photoelectric conversion signals read out by said read-out means, and for outputting information regarding the direction of the observer's visual axis.