If you like reading outdoor while suffering presbyopia and nearsightedness or farsightedness at the same time, bifocal reading glasses are generally superior to single vision reading glasses because they can do a great job in providing vision correction and protect you against harmful UV rays.
It is easy to interpret that the two basic elements of bifocal sunglasses are vision correction and UV protection. Being in an outdoor environment, these two elements are to some degrees equally important. Achieving good performance during sports or cycling depends highly on appropriate vision correction. But protecting the eyes from harmful UV rays is also important.
Yes. Bifocal sunglasses are used for both vision correction and UV protection. They can help people who get nearsightedness and presbyopia see clearly when they are outside and also protect them from harmful UV rays.