Apparatus and method for determining a position of an eye
AssigneeBausch & Lomb Incorporated
InventorsMing Lai, Barry T. Eagan, Lloyd G. Allred
Life of this patent
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Abstract
An apparatus for determining a position of a subject's cornea, comprising a camera, a first illumination apparatus adapted to provide a first beam of light and a first diffuse portion of light that are coincident, and a second illumination apparatus adapted to provide a second beam of light and a second diffuse portion of light, that are coincident. In some embodiments, the first, second, third and fourth images are disposed on the midpoints of a square, when a cornea is located along an optical axis of camera.
Claims19
An apparatus for determining a position of a subject's cornea, comprising:
- a first illumination apparatus adapted to provide a first beam of light and a first diffuse portion of light, the first diffuse portion emanating from a point coincident with the first beam;
- and
- a camera,
- the first illumination apparatus and the camera being configured and arranged such that the camera forms a first image of a scattering point of the first beam using light scattered from the cornea, and a second image of the first diffuse portion reflected from the cornea.
An apparatus for determining a position of a subject's eye, comprising:
- a first illumination apparatus adapted to provide a first beam of light;
- a second illumination apparatus adapted to provide a second beam of light;
- a first point source illumination apparatus;
- a second point source illumination apparatus;
- and
- a camera having an optical axis,
- the camera, the first and second illumination apparatus and the first and second point source illumination apparatus being configured and arranged such that, when the eye is located at a given position, (i) light from the first beam and light from the second beam scatter from a cornea of the eye to form first and second images at the camera respectively, the first and second images being disposed about a first point that is a first predetermined distance from a point at the camera corresponding to the apex of the cornea of the eye, and (ii) light from the first point source and light from the second point source reflect from the cornea to form third and fourth images at the camera respectively, the third and fourth images being disposed about a second point that is a second predetermined distance from the point at the camera corresponding to the apex of the cornea of the eye.
An apparatus for determining a position of a subject's cornea, comprising:
- (A.) a first illumination apparatus comprising
- (i.) a first laser adapted to provide a first beam of light, and
- (ii.) a first aperture disposed in a path of the first beam and adapted to generate a first diffuse portion emanating from a point coincident with the first beam;
- (B.) a second illumination apparatus comprising
- (i.) a second laser adapted to provide a second beam of light, and
- (ii.) a second aperture disposed in a path of the second beam and adapted to generate a second diffuse portion emanating from a point coincident with the second beam;
- and
- (C.) a camera,
- the first laser, the second laser, the first aperture, the second aperture, and the camera being configured and arranged to form at the camera
- (i) an image of a scattered portion of the first beam scattered from the cornea,
- (ii) an image of the first diffuse portion reflected from the cornea,
- (iii) an image of a scattered portion of the second beam scattered from the cornea, and
- (iv) an image of the second diffuse portion reflected from the cornea.
Dependencies are inferred from the claim text.