Alsanza aspheric IOLs designed to control corneal positive spherical aberrations with its mild spherical aberration correction. 24H aspherical correction leaves weak spherical with longitudinal focus as young adaptive eye behaves.
Provides continuous contrast sensitivity in low light conditions as well as photopic conditions.

Why Aspheric Correction is so crucial?

When parallel rays pass through the spherical surface, the central rays focus on more posteriorly and peripheral rays focus more anterior progressively. In the IOLs without aspherical correction, peripheral rays are bent too much .Specially at dim night conditions, Spherical aberrations increase as a result of expanded puppil size due to  defocusing of improper refracted light.

Total spherical aberrations will result;

• Astigmatism-like aberration
• Light scatterings in mesopic conditions