Single vision lenses are uncoated, plastic lenses with a single prescription that corrects myopia, hyperopia, or astigmatism.
Standard bifocal lenses
Bifocal lenses are uncoated, plastic lenses that correct both for distance and near vision in individuals with presbyopia. The top of the lens corrects for distance vision. In the lower part of the lens, there is a visible semicircle ground into the lens that corrects for near vision.
Trifocal lenses
Trifocal lenses are uncoated, plastic lenses that correct for vision at three distances. The top of the lens corrects for distance vision. In the lower part of the lens, there is a visible semicircle ground into the lens that corrects for near vision. Just above this semicircle is an additional lens segment that corrects for distances of about an arm’s length away.
Lenticular lenses
Lenticular lenses are designed to treat eye conditions that are more serious than simply myopia, hyperopia, presbyopia, or astigmatism. They are often prescribed after cataract surgery for patients without intraocular implants.
Progressive lenses
Commonly called “no-line bifocals”, progressive lenses are bifocal or trifocal lenses that have an invisible corridor of increasing power that leads from the distance portion of the lens down to the reading portion.
Polycarbonate lenses
Polycarbonate lenses are made of a material similar to standard plastic, but are lighter in weight and thinner than uncoated plastic lenses. They offer protection from surface abrasions like scratch resistant coated plastic lenses, and they do not shatter like glass or standard plastic lenses.
Photochromic lenses
Photochromic lenses are light sensitive glass lenses. The glass contains silver halide crystals that darken when exposed to ultraviolet (UV) light and become clear when removed from the light. In their darkened state, photochromic lenses offer protection from potentially damaging UV rays.
Transition lenses
Transition lenses are light sensitive plastic lenses, which makes them lighter in weight than photochromic glass lenses. They become darker when exposed to ultraviolet light and lighten when removed from the light. Transition lenses resist UV radiation both when light and dark, and the lenses are scratch resistant.
Scratch resistant coated lenses
Scratch resistant coated lenses offer protection from most surface abrasions. The coating is included as a part of polycarbonate lenses, but available as an option that is applied to the surface of standard plastic lenses after the lenses are ground.
Glass lenses
Glass lenses are generally heavier than plastic lenses and resist scratching better than uncoated plastic lenses.