Eyeglasses come in a variety of types. This includes a single-vision lens with one power or strength over the entire lens, or a bifocal or trifocal lens with multiple strengths over the entire lens.

Monofocal and multifocal lenses are both types of artificial intraocular lens (IOL). A monofocal lens has one focusing distance, whereas a multifocal lens can focus on close and far distances at the ...