Bifocal Lenses
Bifocal lenses are the most common type of multifocal lens. These lenses correct both near- and long-distance vision by combining two prescriptions into a single lens. The upper part of the lens is designed to correct distance deficiencies, while the bottom portion is a near-distance lens meant to correct up-close vision.
These are excellent choices for people who use both distance and reading glasses, so they do not need to carry around two pairs of glasses wherever they go.
Bifocal & progressive prescriptions (multifocal)
A multifocal prescription will include an ADD value, sometimes marked as NV. This indicates the required strength for the near prescription in your lens.