Optics: eye examining – vision testing and correcting – Eye examining or testing instrument – Objective type
Patent
1990-08-03
1992-10-27
Bovernick, Rodney B.
Optics: eye examining, vision testing and correcting
Eye examining or testing instrument
Objective type
351247, A61B 310
Patent
active
051593610
ABSTRACT:
A system, method, and apparatus for obtaining the corneal topography of an object using computer analyzed rasterstereographic images. The object may be nontransparent and diffusing, or it may be transparent and nondiffusing, such as a cornea. Rasterstereographic images of a cornea are produced by staining the cornea with a fluorescein solution which projects a light and dark line pattern onto the cornea through a grid. When obtaining the topography of a cornea, several different filters are used for producing and obtaining a grid image. An image processor uses unique software to store and analyze data extracted from the grid pattern. A video camera, an illuminator, the filters, and the grid may be mounted on a microscope. One embodiment uses a grid with vertical lines. Another embodiment uses a grid having intersecting horizontal and vertical lines for exhibiting surface details in a two-dimensional x-y plane. A computerized method and associated apparatus uses the data from the x-y plane to determine the projected grid intersection points (PGI) on the surface of the cornea by intersecting a light ray formed by the grid intersection (GI) points on the actual grid in the projected system with a light ray formed by the grid intersection (IPGI) points of the image in the camera system.
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Cambier James L.
Strods Salvins J.
Bovernick Rodney B.
Kikel Suzanne
Par Technology Corporation
Silverman Arnold B.
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