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What are Polarized Sunglasses?

A pair of polarized sunglasses.
Polarized sunglasses are designed to reduce glare from light that is reflected off of surfaces like water or snow.
Couple wearing sunglasses with polarized lenses.
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  • Written By: Mary McMahon
  • Edited By: Bronwyn Harris
  • Last Modified Date: 04 October 2014
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Polarized sunglasses are designed to reduce the glare from surfaces like water, snow, and glass. They can be highly useful for sports, driving, and fishing by helping the participant in these activities to see more clearly, allowing for the avoidance of potential hazards. While they may be somewhat more expensive than conventional sunglasses, some consumers prefer polarized sunglasses because they selectively block out glare, rather than making the whole field of vision dimmer, which can be dangerous in some situations.

Light has many interesting properties, especially when reflected from another surface. Polarized sunglasses take advantage of one of these properties, known as polarization. Normally, a light source produces waves which go in all directions. When light is bounced from a surface like glass, water, or snow, the light waves polarize, meaning that they orient along an axis, which is usually horizontally. A vertical polarizing lens can reduce the brightness of these light waves while still allowing optical information through.

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Because of their vertical polarizing orientation, polarized sunglasses are ideal for dealing with reflective glare conditions, depending on the angle. Experimentation with polarized sunglasses can yield an angle at which no light is filtered out, because the glasses are horizontally aligned along with the glare. At other angles, polarized sunglasses will filter out some or all of the glare, allowing the wearer to see with comfort and without potential eye strain. Polarized sunglasses are unfortunately not as useful when the sun is directly overhead or low to the horizon, because the angle of the reflected light waves changes from this horizontal configuration.

Polarized sunglasses are primarily used in situations where the wearer needs to be able to clearly see, but also needs to have dangerous glare filtered out. Glare makes vision difficult because the light hurts the eye and obscures details which may be hidden behind it. Conventional sunglasses will block out glare, but they will also block out subtle details about the wearer's environment which may be dangerous. These polarized sunglasses designed for outdoor use usually come in a variety of configurations from very lightly tinted and mildly polarizing to heavily tinted and strongly polarizing. Some also integrate color tinting for visibility in specific conditions such as snow.

Some 3-D movies also use polarizing glasses. Usually one lens is horizontally polarized and the other one is vertically polarized, so that each eye sees a slightly different version of the movie screen. The eyes attempt to reconcile the two images for the brain, and the result is the illusion of a three dimensional image. Experimenters with several spare pairs of 3-D glasses lying around can play with the effects of polarization for themselves.

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Discuss this Article

anon328312
Post 20

I think 'REVO' makes the best polarized sunglasses out there. They claim they used the same technology NASA used for space.

anon276923
Post 17

Why go polarized? My regular ones work just fine!

anon272332
Post 16

Maiu Jim sunglasses are the best available.

pchonline
Post 15

Good article on what are polarized sunglasses. If you're looking for the best polarized sunglasses for motorcycle riding, skydiving, and military applications, Liquid Eyewear is your best choice.

amypollick
Post 14

Gotta have my polarized sunglasses. Mine are ancient and I probably need to get some new ones. When I do, I'll probably go to the local sporting goods store and get some that bass fishermen wear. Those are made especially for cutting down on glare and blocking the UV rays.

I wear my sunglasses even on cloudy days. My mom's opthalmologist told her that exposure to UV rays can cause cataracts later on. So my sunglasses are *always* perched on my nose when I'm outside in the daytime. I wouldn't go without them.

jeffioptix
Post 13

I play a lot of sports, including cycling and I found polarized sunglasses really take the glare off the road.

anon180779
Post 11

Best polarized glasses are police sunglasses. i have a pair and it is brilliant. I can see more clearly for a much longer distance than with usual sunglasses. Well worth the extra cash you spend on them.

anon171227
Post 10

I currently have a pair by Polaroid and compared to a previous pair by Oakley they are significantly inferior. Oakley are definitely worth the extra cash.

bodryn
Post 9

Polarized filters can be very useful in digital photography. The sky is also polarized at 90 degree angles and one can achieve very dark sky backgrounds for clouds. These filters can also dodge reflections on water, and in windows, allowing clearer photographs.

anon143615
Post 8

i develop problems with my eyes whenever i use computer. i experience blurred vision after followed by a terrible headache. can i use polarised sunglasses and if yes, which configuration?

anon115730
Post 7

can polarised sunglasses used to watch 3d vision? Please help me out.

anon86662
Post 6

@yashg: it cannot be harmful as it just blocks certain rays which are reflected from some objects.

i don't know the name, but they are multi-layered images creating the effect of covering the image beneath by the reflection of top layer.

@syl59: these screens doesn't filter according to the wave length but according to polarization state.

the fact that the reflected light, which causes glare, from water or other surfaces are polarized makes them useful in filtering those polarized light and to reduce the glare.

anon86427
Post 5

i bought (20/5/2010) Serengeti sunglasses with lenses "555nm polarized" - they are excellent!

yashg
Post 4

Is there any potential affect on eyes if used for longer time? Yesterday one optician showed me a image which I could only see with polarized glasses and not with naked eyes. What are these images called?

anon61116
Post 2

What are the best polarized sunglasses? I know Polaroid invented them and the quality is good, but any better?

syl59
Post 1

what wave length of electomagnetic radiation does a anti glare screen filter have?

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