OpenOptix ABO Study Guide - Laramy-K Optical

Now, if we find the curve on the front surface of the lens to be +6.00 D and determine the
back surface to be toric with a measurement of -8.00 D in the 90º meridian and -5.00 in
the 180º meridian our power determination would look like this:
Aspheric Lenses
Aspheric lenses are defined as lenses that are non-spherical. This non spherical surface
encompasses all kinds of lenses from aspheric, atoric, progressive, and aphakic.
Aspheric lenses are defined as lenses that are non-spherical. This non spherical surface
encompasses all kinds of lenses from aspheric, atoric, progressive, and aphakic. So if all
these lenses fall in the definition of an aspheric lens, how do we further define and
differentiate aspheric lenses in all their forms.
Aspheric
Generally aspheric in the ophthalmic industry defines a lens surface that varies slightly
from a spherical surface. This variation is known as the eccentricity of the lens and can
further defined as conic sections. Sections of a cone represent various curves that are
used in ophthalmic surfaces, for instance circle, ellipse, parabola, and hyperbola.
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