The big difference between prescription sunglasses and regular sunglasses is the lenses difference. The lenses of normal sunglasses are non prescription sunglasses, while prescription sunglasses are fitted with prescription sunglasses. Without rx lenses, people who have vision problems such as myopia can not see clearly when they only wear normal sunglasses. So these people may wear sunglasses over their prescription contacts. With the advent of prescription sunglasses, these people can have a clear clarity and get uv protection at the same time. Therefore, prescription sunglasses are quite a life saver for people who need vision aids.
As we all known, the sunglasses are mainly designed for protecting our eyes under sun and can't correct eye vision. Those people who have eye problems, like nearsightedness, farsightedness, couldn't wear sunglasses in the past due to the limitation. Nowadays, the prescription sunglasses are created for not only protecting eyes under sun but also correcting eyes. That is to say, the big difference between regular sunglasses and prescription glasses is the lens.