A polarized lens’ primary function is to reduce glare—that is, light reflected from a flat surface which greatly diminishes color and contrast. A body of water, a windshield, and even an asphalt road are all notorious producers of polarized light. Fog and haze from water vapor result in similar glare.

Polarized lenses are most useful when trying to see through these reflecting surfaces, like when fishing, boating, or driving. Non-polarized glasses with a good tint, a lens coating such as iridium, or a quality mirrored lens increase contrast and definition, and even reduce glare by cutting out certain wavelengths of light—but nothing compared to a polarized lens. Polarization acts essentially like blinds, blocking out the offending glare entirely. Although coatings don’t do as thorough a job as polarization, they’re still immensely popular because of price. For activity on snow and ice, a coated lens is actually sufficient. Most glacier glasses are coated in some fashion, but not necessarily polarized.

(L to R) Smith Recorder, Maui Jim Kona, Oakley Square Wire 2.0, and Spy Scoop HS

Bottom Line: If you spend a lot of time on the water (boating, fishing, or sailing, for example) or if you drive long distances, we recommend polarized sunglasses.