Glass: Lenses that have great clarity and are more resistant to scratching, however, they are heavier. • Plastic: Lenses that are lighter weight and more comfortable, however they scratch more easily.
Progressive: Lenses that are line-free. The power gradually changes from distance correction to arm’s length to reading, moving invisibly from the top to the bottom of the lens. Standard progressive lenses use older technology, while premium progressive lenses use more current technology. Premium progressive lenses allow for a smoother blending in the lens as the prescription changes and may also provide clearer peripheral vision.
Plano: Lenses that do not have any correction and are often used for cosmetic purposes.
High-Index: Lenses that have a higher index of refraction, meaning light travels faster through the lens to reach the eye than with traditional glass or plastic. They are denser so the same amount of visual correction occurs with less material. This allows the lens to be thinner and look better cosmetically.
Polycarbonate: The most durable lens on the market. They are especially popular for children’s prescriptions and industrial safety glasses because of the protection they provide against breakage.
Photochromic: Lenses that change from light to dark depending on the intensity of ultraviolet light exposure. This option is often sold under the “Transitions” brand.
Polarized: Lenses that reduce the glare from water and other flat surfaces making the outdoor experience more pleasant and easier on the eye. Boaters and fishermen appreciate this type of lens.
UV Protection: A treatment is applied to lenses to block the harmful portion of ultraviolet light in sunlight.
Scratch-Resistance: A coating applied to plastic lenses to increase their resistance to scratching and pitting. While no lens is ever entirely “scratchproof,” a scratch-resistant coating reduces the chance of lens scratching.
Anti-Reflective: A coating applied to lenses to reduce the intensity of reflections. Bright lights from cars or computer screens, for example, are minimized. They also reduce the intensity of reflections that other people see on the front surface of the lenses so they are more cosmetically appealing.
Solid Tints and Dyes: Lenses with solid color tints and dyes have the same color density throughout. Plastic lenses can be dyed, while tinted glass lenses are made from colored glass. These options may be selected for cosmetic purposes or to reduce the amount of light coming through the lenses.
Plastic Gradient Dyes: Lenses with plastic gradient dyes are usually dark at the top and gradually lighten toward the bottom of the lens. This option is typically for cosmetic purposes.
High-Luster Edge Polish: Glass and plastic lens edges can be polished to a high luster resulting in clear and shiny lens edges. This option is often selected with rimless frames to disguise the edges of the lenses, especially with thicker lenses.