Polarized Sunglasses

This week marks the official start of the summer season.  I’ve been getting a lot of questions about the differences between polarized and non-polarized sunglasses, so here’s the answer for all those who are curious.

Polarized sunglasses have a polarizing filter which helps reduce glare and improves the quality of your vision.  When sunlight travels through air, it eventually reaches surfaces such as cars, water, asphalt roads, etc…  The light hits theses reflective surfaces and bounces off parallel to it, usually in a horizontal orientation.  For example, when you look at the hood of a car under the sun, the glare off the surface is from reflected sunlight vibrating in a horizontal direction.  Since the majority of glare is caused from horizontally-oriented light rays, polarizing filters are set vertically so that only vertically-oriented light rays can go through the filter while horizontally-oriented light rays are blocked out.  These lenses are most beneficial to those spending time on water or those who drive because most of the glare in these cases is caused by horizontal surfaces (e.g. water and the hood of your car).

Polarized sunglasses are not recommended for golfers because some find it more difficult to read the green.  Pilots and police officers should also refrain from wearing polarized lenses because it is difficult to read LCD displays.

(Fun fact from Cheryl, our optician: if you tilt your head at 45 degrees to the right while wearing your polarized sunglasses, your LCD screens should black out.)

Dr. Jessica Chang, OD  drchang@avenueeyecare.com