Tomey TMS-5, Instruction Manual

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Height [Anterior]
Elevation [Anterior]
Elevation [Posterior]
The height of the cornea is shown in microns on the
height map. The height is calculated by the personal
computer, based on techniques using Zernike
Polynomials.
(Zernike Polynomials were developed by Doug Brenner,
Ph.D. of Computed Anatomy, Inc. in cooperation with
John Greivencamp, Ph.D. of Arizona State University and
Stephen D. Klyce, Ph.D of Louisiana State University.)
(Fig. 2)
The elevation map shows the declination from the
spherical surface obtained by subtracting the height of the
reference sphere BFS (Best Fit Sphere) from the corneal
height.
Positive value: The measurement point of the cornea is
above the reference sphere.
Negative value: The measurement point of the cornea is
below the reference sphere.
(Fig. 1)