Polarized Single-Vision lenses(full time wear)

Do these lens get darker in the sun.then turn lighter indoor ?

Actually, the lenses you want are photochromic lenses not polarized lenses. Photochromic lenses are clear indoors and darken automatically outdoors.

Do you have any idea about where can buy cheap photochromic eyeglasses? I always wear 1.61 prescription lenses, do you know the average cost for 1.61 photochromic lenses? Thanks for your help!

The professional online prescription glasses store PrescriptionGlassesOnline.net can supply Super Thin 1.61 high index photochromic lenses at cheap price USD99.95. There are also many discount eyeglasses frames starting from USD7.95 for you to choose from.