I use this type of sunglasses. They are basically a copy of Ray Bann. check out RB's site or go to a RB stockist to learn about the colour tinting of the lenses. The copy RBs should be made of glass which should be "optically correct", and the correct tint for you.The shape or style is designed to block stray light. I have seen some bad copys and some very good ones . There are huge variations. SO, TRY BEFORE YOU BUY. Expect to pay about a fiver for a copy.
Hope this helps
Crowe
Hope this helps
Crowe