What type of contact lens is designed to correct both spherical error and astigmatism?

Toric lenses are specifically designed to correct both spherical error and astigmatism. These lenses have a unique shape with different powers in different meridians to accommodate the irregular curvature of the cornea that causes astigmatism. The varied thickness of the lens allows for proper light refraction to focus images accurately on the retina, effectively addressing both spherical errors (myopia or hyperopia) and astigmatism in one lens.

In contrast, bifocal lenses are used primarily to assist with both distance and near vision and do not account for astigmatism. Monovision lenses are designed for individuals who need different prescriptions for distance and near vision, typically by correcting one eye for distance and the other for near, but they do not specifically target astigmatism. Multifocal lenses provide multiple zones for vision correction, primarily for presbyopia, but like bifocal lenses, they do not necessarily correct astigmatism unless they are designed as toric multifocal lenses, which is a separate classification. Thus, toric lenses remain the best option for simultaneous correction of spherical error and astigmatism.