Sphere Component: Spherical component in a lens includes spherical correction in diopters for each power specification. Powers can be convergent (ex. +3.00D) to correct Hyperopia or divergent (ex. -4.75D) to correct Myopia. If neither convergence nor divergence is required in the prescription, "Plano" is used to denote a refractive power of zero.

Cylinder Component: Cylindrical component is used when the patients need two different correction powers in two different meridians (horizontal and vertical). This is specified by describing how the cylinder differs from the sphere power. Power evenly transitions between the two powers as you move between the meridians.

Axis Component: The axis component defines where the two powers (sphere and cylinder) are located. The sphere is almost always 90 degree from the cylinder.