What are polarized sunglasses? This post aims to clarify the facts against the myths regarding polarized shades.
Keep reading to find out how polarization works, what are the benefits of polarized lenses and many other interesting information of polarized sunglasses. After reading this post you should have a firm knowledge if polarized sunglasses are worth your money.
Table of contents:
- How Do Polarized Sunglasses Work?
- Advantages of Polarized Sunglasses
- Disadvantages of Polarized Sunglasses
- Two Types of Polarized Lenses
- How to Check If Your Lenses are Polarized?
- Facts & Myths about Polarized Sunglasses
- Who Should Wear Polarized Sunglasses?
- Are Polarized Sunglasses Worth Your Money?
- Popular Polarized Sunglasses
How Do Polarized Sunglasses Work?
Polarized sunglasses lens contains a filter that blocks horizontal light. Horizontal light is highly polarized light reflected by most flat surfaces like water. In general, solar light is actually non-polarized but whilst reflected it comes polarized (more or less).
Glare reflected from water can be almost completely horizontally polarized, especially if the sun altitude is between 30 and 60 degrees. Polarized sunglasses will come in need. On the other hand, if the sun is very low or high and waters are calm there will be only a little help for using polarized sunglasses.
All reflections from objects above water surface are partially polarized. Glass create more horizontal light than metal. Roads reflect glare, also bright reflections from car surfaces may be disruptive when the sun is behind or in front subject to driver.
From image below, you can see how efficiently polarized lenses block glare and haze.
In turn, snow reflects very little horizontal light cos of its irregular nature of surface which kind of refract light in different directions. But, polarized lenses may help a bit to be able to see more comfortably thru haze near the horizon.
Advantages of Polarized Sunglasses
Benefits of polarized shades compared to non-polarized sunglasses.
- Cuts glare and haze from water, car hoods, roofs etc. making polarized lenses beneficial for outdoor activities like fishing, boating, sailing, biking, jogging, golf, tennis…
- Increase contrast sensitivity and color perception to improve vision
- Enhance clarity of vision to get more depth perception and visual accuracy
- Reduce light transmission making it comfortable to watch displays for light sensitive people, especially post-cataract surgery patients.
- Reduce effectively eye strain preventing serious vision problems
- Helps seeing fish and rocks below the water surface (excluding looking at straight down)
Disadvantages of Polarized Sunglasses
Polarized sunglasses are not always the right choice for you.
- More expensive than non-polarized sunglasses
- Downhill skiers can’t see reflections from icy areas on surface and may end up in serious accidents
- Skiers and snowboarders may not see small jumps in certain areas because blockage of shadows
- Not worth in snowy surroundings since reflections of snow are not polarized
- Motorcyclist should avoid polarized sunglasses as they may not distinguish wet/oily pavement
- Reduce the visibility of images produced by LCDs and LEDs – especially pilots should not wear polarized sunglasses if they have LCDs on flight deck
- If the sun is very high or very low polarized lenses don’t help much.
- Tilting your head may weaken usefulness of polarized lenses because its filters block horizontal light most efficient when you hold your head in normal position.
- Polarized lenses have always some color (the darker the better) so obtaining clear lenses is impossible.
Two Types of Polarized Lenses
.75 mm polarized lenses are suggested for casual activities without risk of impact, like golf. They are also cheaper simply because the polarizing film used for them is thin.
1.1 mm polarized lenses are more expensive. The polarized film used to make these is thicker. It’ll provide you additional strength and scratch resistance.
Notice that both types of lenses offer the same amount of protection from glare. Thicker lenses are just stronger. So, you may want to buy 1.1 mm polarized lenses only, if you do some serious sport.
How to Check If Your Lenses are Polarized?
To find out if your current shades are polarized try to seek letter “P” from your sunglasses. If you can’t find it or you doubt that the symbol of polarized lens could be fake, try the next simple method.
Rotate your glasses 90 degrees so they are on vertical line and look thru one lens. In this position you should see glare off horizontal surfaces if it’s shining. When you orient sunglasses normally and see the glare eliminated you know that your sunglasses are polarized.
Facts & Myths about Polarized Sunglasses
Polarized 3D glasses are great for reducing glare.
Myth! Filters are oriented badly for that purpose. You may also start feeling dizzy and see objects around you with different intensities depending on the eye.
Polarized lenses give excellent UV protection.
Not always! Usually they protect against UV rays, but it has nothing to do with polarized lens filter itself. Make sure you buy quality polarized sunglasses which include 100% UV protection coating. If you buy cheap tinted polarized glasses without UV protection they may do some serious damage because tinted polarized lenses will dilate the pupil allowing more UV radiation to enter your eye.
Polarized lenses reduce snow blindness (photo keratitis).
Maybe! Snow blindness is caused by reflecting UV light. You will need UV protection coated sunglasses to avoid that. Most quality polarized lenses are UV coated.
It is possible to get photochromic (light sensitive lenses, change from dark to light depending are you inside or outside) lenses with polarized filter.
Fact! These are great for persons who need glasses anyways due to vision problems. Remember that car windshield usually blocks some UV light so photochromic lenses don’t get as dark as some people would like while driving. Polarized filter can be obtained also with bifocal lenses.
Polarized lenses are great for all kinds of winter activities.
Not really! Snow glare is not polarized. You may get little help blocking some haze near the horizon but as discussed in the preceding chapters there are some cases polarized lenses will work against you in snowy environment.
Polarized lenses are effective in all sunglasses frames.
Not always! Some sunglasses frames tilt towards your face. Example: tilt comparison between Ray-Ban New Wayfarer and Original Wayfarer. Tilted frames do not take full advantage of polarized lenses.
Who Should Wear Polarized Sunglasses?
Polarized sunglasses have been most popular with sailors and fishermen because the glare of the sun reflections on the sea is highly polarized.
Recently many outdoors enthusiasts have discovered the benefits of polarized lenses as well. Besides boating, top outdoor activities in which polarized sunglasses can be utilized are biking, driving, golfing, jogging and various water sports.
Polarized sunglasses are a must choice for light-sensitive folks. Especially for cataract surgery patients and people who work continually near window or other flat surfaces like hood of the car that reflects intense light waves.
Downhill skiers don’t usually use polarized sunglasses because they block reflections from icy patches which could lead to an accident. Although they are often mistakenly advertised for that purpose widely.
Polarized lenses usually reduce the visibility of images produced by LCD screens. That for they are not recommended for pilots, boaters or drivers who use liquid crystal displays.
Are Polarized Sunglasses Worth Your Money?
Polarized sunglasses are a great choice for people who spend plenty of time outdoors, especially for people near water surfaces. From the chapters above, you have learned the cases when they are not the best option.
Wearing polarized shades is not just another fashion statement. Oh yes, polarized sunglasses allow you to express your personality, but most of all they are health accessory!
Majority of people can’t go back to regular sunglasses after wearing polarized shades. They’re worth the money! Just make sure you don’t wear them in certain situations, stated in previous chapters, that could get you in trouble.
Popular Polarized Sunglasses
Here are 4 popular polarized sunglasses that are both protective and stylish.