Trivex is the newest technology that provides superior optics, increased durability and is the lightest material available in prescription lenses. Trivex's clarity results in reduced distortions and sharper vision. Trivex is used by our military due to it's exceptional impact resistance and strength.
High index lenses are usually recommended for higher prescriptions to produce thinner, lighter and better looking lenses.
Polycarbonate lenses are thin, light, impact resistant and less expensive. While most newer lens options have better optics, polycarbonate is a less expensive option for those on a budget.
Primarily used as safety lenses polycarbonate is often recommended for children because of the higher impact resistance.
Traditional plastic lenses (called CR 39 for the batch number of the original mixture created) are much lighter than glass lenses. They can be tinted almost any color and darkness. They are more easily scratched than glass lenses; however, a scratch resistant coating may be applied to reduce the susceptibility to scratches.
Plastic lenses are very inexpensive for people who don't mind a little thicker lens.
Glass lenses are the oldest material used for spectacle lenses but rarely used today. They have excellent optical properties and are scratch resistant but unfortunately they are considerably heavier then most other lenses. Glass is seldom recommended due to its tendency to shatter upon impact.