Polarized lenses are a type of sunglass lens that contain a special chemical filter that blocks some of the light from passing through the lens. This filter is lined up specifically to block horizontal light waves, which are responsible for glare and eyestrain. By blocking these waves, polarized lenses reduce glare and improve vision and safety in the sun. They also make colors appear more vibrant, increase contrast, and reduce the symptoms of eye strain. Polarized lenses are especially useful for people who spend a lot of time outdoors, as they protect the eyes from harmful light that could be potentially blinding. Polarized lenses are not designed to protect against UV rays, but many polarized sunglasses also offer UV protection. The disadvantages of polarized lenses include that they can make it difficult to see certain digital screens and LCD displays, and they may not be suitable for certain activities such as skiing or snowboarding.