Poly carbonate
Poly carbonate lenses are growing in popularity because they are the thinnest and lightest in weight. They are also the most impact resistant lenses available today, and are commonly used for children's glasses, sports glasses and safety glasses. If, however, you do not require the safety aspects of poly carbonate lenses, a high index material is possibly a better choice.
High Index
For people with a higher prescription, High Index materials allow thinner, lighter, more attractive lens without compromising optical quality.
Plastic
CR-39 plastic is the most widely used material for eyeglass lenses. It's lighter in weight than glass, but not as scratch resistant. A scratch resistant coating is highly recommended for plastic lenses.
Glass
At one time, glass was the only choice for corrective lenses. Glass provides good scratch resistance and can accommodate a wide range of prescriptions. However, glass is heavy and can be uncomfortable to wear. It's also easier to break or crack. If you're active you may want to select another lens material.
Photo chromic Lenses
Photo chromic lenses have a variable tint that changes with the amount of available light. In bright sunlight, they darken; indoors, they become clearer. They are available in both glass and plastic.
