Lenses with darker tints, such as gray or brown, block the most sunlight by reducing glare and providing high levels of UV protection. These colors are ideal for shielding eyes from harmful rays. Polarized lenses in gray or brown further enhance contrast and reduce glare, making them suitable for outdoor use. Photochromic lenses are another option, as they darken in sunlight and lighten indoors, offering convenient all-day protection.