1, colored lenses: also known as the tinted lens was the lens production process, plus chemicals, lens color to absorb specific wavelengths of light. This is the most commonly used type of lens sunglasses.
2, paint the lens: it works with the same colored lenses, made only in a different way, it is a color coating on the lens surface, color above the deep and then gradually down light. More commonly used in prescription sunglasses lenses.
3, polarized lenses: to filter the sun shines on the surface, land, or snow parallel to stimulation of light, add a vertical special coatings on the lenses. Suitable for outdoor activities (such as offshore activities, skiing or fishing) to use.
4, color-changing lenses: the addition of chemical substances on the lens, so that the original transparent lenses, when strong ultraviolet radiation, will become colored lenses, also known as "the photographic lens". Of the main protective UV eye burns, suitable for indoor and outdoor use, especially in high altitude and strong ultraviolet rays.