Single Vision- These lenses contain the same prescription throughout the entire lens. They are used by individuals with normal focusing ability or
general purpose. Those who normally wear a bifocal can chose a single vision lens to correct their vision either at a distance or for reading.
Flat Top Bifocals- These "traditional" lined bifocals have the advantage of a simple set of two optics. Above the line is the distance prescription and below the reading. They are generally the easiest bifocal for adaptation but some find the line distracting and/or cosmetically undesirable. The bifocal can be made in different widths to accommodate one's needs.
Trifocals- Again, "traditional" trifocals are the same design as flat top bifocals with a small segment added over the bifocal for viewing at an intermediate distance. These lenses are often
very easy to adapt to after wearing the flat top bifocal and are very advantageous to the computer user.
Progressive Lenses- These "No-Line" lenses give all the optics of a trifocal but with a continuous, clear and gradual change in the power. Because of its design, the reading area is a bit narrower than the traditional trifocal. They look no different than a single vision lens and weigh about the same. Because of their optical and cosmetic advantages, they are by far, the lenses of choice for first time bifocal wearers.
