“Color is a matter of personal preference, and the intensity of the color – whether brown, green or gray – doesn’t matter because it’s the absorption of ultraviolet rays that protects you, not the color or darkness of the lens.You can even have clear lenses that protect you from UVA/UVB.
“Grey and green are fairly neutral, so they won’t change the colors you see. Psychologically, people think more light comes through brown lenses because they make the colors warmer. I think they make sunsets prettier because you get more of the red finish with a brown lens than you would with a gray lens.
“Some people think mirrored lenses are just fashion, but mirrored sunglasses reflect and block light, that’s why they’re even darker.
“Polarized lenses eliminate reflected light off a flat surface. When you go to the beach you get glare because the ocean is flat or when you drive the glare also comes from other cars, road surfaces and shop windows. Polarization doesn’t give you better protection against light; it just reduces glare. But there’s a problem: you can’t look at your cell phone with polarized lenses because it will be black. You have to turn your phone 35 degrees to be able to see it.”