Prescription sunglasses are available in all lens materials, including High index lens, Polycarbonate, regular (CR-39) plastic, high impact lens and glass. Though glass lenses arguably provide the best optical quality, they are no longer the most popular choice for sunglasses. This is because they are much heavier than lenses made of other materials, and they can shatter easily.
You don’t have to sacrifice fashionable style or high-level sports performance if you want prescription sunglasses. There are many different style glasses frame available that will accommodate a prescription lens. Online cheap glasses retailers like www.cheapglasses123.com offers many stylish, or sporty style sunglasses frames that look just like a regular non prescription sunglasses, but can go with prescription lenses and at very cheap price and high quality.
Another sunglasses option is to purchase prescription eyeglass lenses that have a photochromic or transition lens. Photochromic lenses automatically darken in sunlight and then return to a relatively clear state indoors.
Photochromic lenses are very convenient, but they do have a drawback: It requires UV to activate the darken effect. Because most car windshields block a significant amount of UV, photochromic lenses usually don’t darken very well inside a car.
For the ultimate prescription sunglasses suitable for all lighting conditions, some opticians recommend prescription glasses with photochromic lenses and a frame with integrated magnetic clip-on sunglasses. the magnetic clip-on sunglasses can be conveniently stored in your vehicle for those bright, sunny days when you need a darker driving lens.
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