Method and apparatus for determining eye topology

Apparatus for measuring the topography of an eye characterized by at least one distinct visual feature, said apparatus comprising:

• A) a camera directed along an imaging axis for capturing a two-dimensional image of the eye including the at least one distinct visual feature,
• B) a scanner that generates distance information corresponding to the height distances from an internal reference to the surface of the eye at a plurality of positions during a meridian scan,
• C) means for defining a fixed spatial relationship between said camera and said scanner,
• D) a rotary stage for rotating said scanner thereby to obtain distance information for each of a plurality of meridian scan lines, and
• E) a control connected to said camera, said rotary stage and said scanner, said control including:
• i) means for controlling said scanner to produce at least one height measurement along each meridian scan line during a rotational scanning operation thereby to obtain a plurality of distances at each of the at least one meridian scan line,
• ii) means for causing said camera to capture at least one image of the eye during a rotational scanning operation,
• iii) means for producing incremental rotation of said rotary stage during a rotational scanning operation to generate information for a plurality of meridian scans,
• iv) means for storing, during a rotational scanning operation, the distance information obtained during each meridian scan and its corresponding captured image information from said camera, and
• v) image stitching means for processing the stored distance and captured image information in said storing means thereby to obtain an accurate representation of the topography of the eye.