As a result, people require multiple sets of eyeglasses for different conditions. Bifocal or trifocal or progressive lenses are really just multiple sets of lenses squashed into a smaller form ...

A progressive lens design is like a bi- or tri-focal lens in that it corrects ... You may want to consider Transitions photochromic lenses for your primary pair of glasses. They adjust automatically ...

enabling the wearer to adjust her focus depending on the distance from the object she is viewing—similar to bifocal or progressive-lens glasses. There are also contact lenses that can correct ...