What to Know About Polarized Sunglasses

Polarized sunglasses are designed to reduce glare from surfaces such as water, snow, and glass. Glare distorts the true color of objects and makes them harder to see.

Glare isn't just annoying. It can be dangerous, especially when you're driving. Sun glare has been linked to pedestrian deaths and other traffic accidents.

Polarized sunglasses can help drivers and athletes see more clearly and avoid hazards.

This article explains how polarized lenses work. It also outlines some of the benefits and drawbacks of this kind of eyewear.

How Polarized Lenses Work

Polarized lenses are available in a variety of colors. Their shade depends on the material used to make the lenses. The most common colors are gray and brown, but green, yellow, and melanin color are also popular. Darker colors tend to have a stronger effect.

Here's how they work. Polarized lenses block horizontal light waves. Only vertical waves make it through the filter in the lens. That cuts down on glare.

When sunlight strikes a surface at a certain angle, it's reflected back at the same angle. For example, if light strikes a flat, horizontal surface like a road, it bounces off at a horizontal angle. Most of the surfaces that cause glare reflect light waves horizontally.

Advantages

A high-quality pair of sunglasses will usually have polarized lenses.

Here are a few advantages of this type of lens:

• Increases your visual comfort
• Sharpens the contrast between light and dark
• Makes objects clearer
• Reduces eye strain
• Allows you to see true colors
• Reduces reflections and glare

Disadvantages

Polarized lenses aren't right for everyone. Some people feel dizzy or disoriented when they look through polarized lenses. Others say everything looks 3-D. Tinted lenses might be a better choice in those cases.

In some professions, people need to read digital numbers on a liquid crystal display (LCD). Pilots are a prime example. Polarized lens can make information on an LCD display hard to read, so they're not a good option for people in those situations.

Some polarized lenses are marketed to help reduce glare while driving. Because they block some light, though, they should not be used at night. Polarized lenses can also make it harder to see icy patches on the road.

Summary

Polarized sunglasses are coated with a chemical filter that cuts glare. They work by blocking the light waves bouncing off horizontal surfaces.

Polarized lenses are helpful when you're driving or participating in sports. They aren't right for every situation, though. If you're driving at night, navigating icy patches, or using LCD devices, these lenses make it harder to see clearly.