Curvature and Refraction Data

The cornea is the main refracting surface of the human eye. Its front (anterior) surface is approximately 1.3cm2 with an average radius of curvature of about 7.8mm. Typical computer algorithms for corneal curvaturemeasurement (known as keratometry) are based on projecting a pattern of concentric rings of light onto the anterior surface of the cornea and numerically determining the relative separation between the images of these reflected rings of light. This models the anterior surface of the cornea as a highly polished spherical mirror. By sampling the curvature at specific circularly equidistant points, a numerical model for the surface curvature may be obtained.