FLAT TOP BIFOCALS: Flat top bifocals are designed so that the upper portion of the lens is for distance and the half moon is for normal reading distance (approx. 40cm.)

TRIFOCALS: Trifocals are designed so that the top is the distance and the half moon is the reading distance. The intermediate ribbon allows one to see at an intermediate distance such as a computer monitor or groceries on a shelf.

PROGRESSIVE: A Progressive lens is the most functional lens. The top portion of the lens is designed for distance. The bifocal increases in power as you travel from the top of the lens to the bottom. This design allows for good vision at a wide variety of distances. Progressive lenses are very popular in that they are cosmetically pleasing. *Note progressives are not all treated equal. Progressive lenses are available in several widths--typically the wider channel progressives allow for ease of adaptation.

SMART SEG: This lens is a progressive lens in a half moon format.

Which type do you need?
If you do a lot of near work with very little intermediate distance demand -- such as reading, needle point, paper-work -- a bifocal may suffice.

If you do a lot of work at an intermediate distance and near -- such as computer user, grocer stocker -- a progressive would be most functional.

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