Eye movement detector
First Claim
1. An eye movement detector comprising:
- a display to be viewed by an operator;
a camera with a lens located near said display and directed in a manner to obtain an image of an operator'"'"'s eye when the display is being viewed;
an illuminator directing an infrared source of illumination coaxial with said camera lens towards the position of an operator'"'"'s eye so that the reflected illumination causes the operator'"'"'s pupil to be brighter than the surrounding part of the eye due to the bright eye effect and also causes a glint reflection from the cornea of the eye;
a computer with memory for analyzing said image of an illuminated operator'"'"'s eye to determine the center of the pupil and location of the glint and utilizing said information in determining the eye-gaze point and correlating said eye-gaze point with where on the display the operator is gazing;
said computer analysis including using said image of the operator'"'"'s eye in a digitized matrix of pixels that is first analyzed by scanning a selected sampling of pixels, which may include every pixel or some lesser number of pixels to determine the boundary as represented by different pixel light intensities between the pupil and the part of eye and face surrounding the pupil; and
said computer analysis further including creating a region of interest in said matrix that surrounds said pupil that is fractionally larger than said pupil and includes said glint with an approximate center of said region of interest being the midpoint of said pupil'"'"'s diameter, said computer then re-scanning the entire region of interest, using said re-scan information in calculating from said re-scan the location of said pupil'"'"'s center and the location of said glint, then determining the pupil-glint displacement between said pupil center location and said glint location and from said pupil-glint displacement calculating said eye-gaze point.
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Accused Products
Abstract
A system for eye movement detection is disclosed that utilizes an infrared light emitting diode mounted coaxially in front of the lens of an infrared sensitive video camera for remotely making images of the eye of a computer operator. The reflected light causes bright eye effect which outlines the pupil as brighter than the rest of the eye and also causes an even brighter small glint from the surface of the cornea. The computer includes graphic processing which takes a video image, digitizes it into a matrix of pixels and analyzes the matrix. Using special algorithms the analysis determines the location of the pupil'"'"'s center and the location of the glint relative to each other and with this information determines where the eye is gazing. If the eye-gaze is for a predetermined time at images in selected areas on the computer screen, the area is selected and results in actuation of other devices or the presentation of additional images on the screen. This is especially useable for handicapped persons to control their environment. Other uses include operator interfacing with workstations, cockpit controls and in industrial environments.
255 Citations
11 Claims
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1. An eye movement detector comprising:
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a display to be viewed by an operator; a camera with a lens located near said display and directed in a manner to obtain an image of an operator'"'"'s eye when the display is being viewed; an illuminator directing an infrared source of illumination coaxial with said camera lens towards the position of an operator'"'"'s eye so that the reflected illumination causes the operator'"'"'s pupil to be brighter than the surrounding part of the eye due to the bright eye effect and also causes a glint reflection from the cornea of the eye; a computer with memory for analyzing said image of an illuminated operator'"'"'s eye to determine the center of the pupil and location of the glint and utilizing said information in determining the eye-gaze point and correlating said eye-gaze point with where on the display the operator is gazing; said computer analysis including using said image of the operator'"'"'s eye in a digitized matrix of pixels that is first analyzed by scanning a selected sampling of pixels, which may include every pixel or some lesser number of pixels to determine the boundary as represented by different pixel light intensities between the pupil and the part of eye and face surrounding the pupil; and said computer analysis further including creating a region of interest in said matrix that surrounds said pupil that is fractionally larger than said pupil and includes said glint with an approximate center of said region of interest being the midpoint of said pupil'"'"'s diameter, said computer then re-scanning the entire region of interest, using said re-scan information in calculating from said re-scan the location of said pupil'"'"'s center and the location of said glint, then determining the pupil-glint displacement between said pupil center location and said glint location and from said pupil-glint displacement calculating said eye-gaze point. - View Dependent Claims (2, 3, 4, 5, 6, 7)
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8. A method for determining eye-gaze comprising the following steps:
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placing on a display multiple individual areas representing different choices that can be made by an operator when viewed by an operator for a predetermined interval of time; obtain an image of an operator'"'"'s eye by a camera with a lens located near the display and when the display is being viewed; illuminate the operator'"'"'s eye by directing an infrared source of illumination coaxial with said camera lens towards the position of an operator'"'"'s eye so that the reflected illumination causes the operator'"'"'s pupil to be brighter than the surrounding part of the eye due to the bright eye effect and also causes a glint reflection from the cornea of the eye; analyze said image of the operator'"'"'s eye by using a computer to determine the center of the pupil and location of the glint and utilize said information to determine the eye-gaze point and correlate said eye-gaze point with whether or not the operator is gazing at an individual area of the display; using said image of the operator'"'"'s eye to produce a digitized matrix of pixels that is first analyzed by scanning a selected sampling of pixels, which may include every pixel or some lesser number of pixels to determine the boundary as represented by different pixel light intensities between the pupil and the part of eye and face surrounding the pupil; and said computer analysis further including creating a region of interest in said matrix that surrounds said pupil that is fractionally larger than said pupil and includes said glint with an approximate center of said region of interest being the midpoint of said pupil'"'"'s diameter, said computer then re-scanning the entire region of interest, using said re-scan information in calculating from said re-scan the location of said pupil'"'"'s center and the location of said glint, then determining the pupil-glint displacement between said pupil center location and said glint location and from said pupil-glint displacement calculating said eye-gaze point. - View Dependent Claims (9, 10, 11)
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Specification