The Difference Between Reflective Lenses & Polarized

Eyeglasses and sunglasses are sold with a variety of lens treatment options, and the terminology can be confusing. For example, many sunglasses have mirrored, or reflective, lenses. However, "anti-reflective" treatments may be applied to any prescription lens. Polarizing, another lens option, is often standard on sunglasses, but may also come with prescription eyewear.

Anti-Reflective Lenses

• Anti-reflective coatings reduce internal and external reflections. Metal oxides are applied to both sides of the lens, resulting in less glare and eliminating the halo effect when the eyeglasses meet reflected light. This reduces glare and makes night driving easier. For other people, it also makes the eyes of the wearer easier to see and allows for better eye contact.

Reflective Lenses

• Mirrored lenses, commonly called reflective lenses, have a mirrored finish that reflects an image back to the viewer. These lenses can be ordered in prescription sunglasses, and thus receive additional types of coatings, but reflective sunglasses can be purchased in stores as well. Mirrored treatments are merely cosmetic and may come in several colors, but they hide the eyes of the wearer and obscure eye contact, which can have social disadvantages.

Polarized Lenses

• Polarized lenses reduce glare coming from reflected light by redirecting the angle of the light rays on the glass. For example, when light bounces off the surface of water or a road, the light rays are polarized, or directed, horizontally and strike the eye in a way that causes glare. A polarized lens redirects such light along a vertical axis instead, counteracting the glare. Polarized lenses are popular with skiers and fishers and can be found on both prescription and non-prescription sunglasses.

Other Coatings

• Prescription lenses come with other optional coatings as well. Thermally cured anti-fog coatings prevent condensation, or fogging, of glasses in sudden changes from cold to warm air. Ultraviolet (UV) coatings reduce the number of harmful UV rays, protecting the eyes from damage. Additionally, lenses can benefit from scratch protection coatings that reduce the change that lenses will be permanently damaged by abrasion.