Polarized Sunglasses and LCD Screens
Do polarized sunglasses and LCD screens work well together? Polarized sunglasses are designed to block horizontally polarized light. Sunlight which comes directly from the sun is not polarized. However, once it strikes a surface like ice, snow, glass etc a portion becomes horizontally polarized which we call glare. Polarized sunglasses
are designed to block horizontal wavelengths (glare) and to allow vertically polarized light to reach our eyes. If you spend a lot of time outdoors in conditions which generate a lot of glare like snow, water or lots of glass then polarizing sunglasses would be a great choice. But are sunglasses that are polarized appropriate for reducing eye strain when using a computer all day?
Liquid Crystal Displays
Computer screens are generally made with LCD (Liquid Crystal Displays) some of which may allow horizontally polarized light through to the viewer. LCD displays are found in cell phones, tv monitors, computers, cars and airplanes. Liquid crystals do not emit light, they only control whether light can pass through them or not. As you can see in the illustration above there are two polarizing plates. When you look directly at your computer screen with sunglasses that are polarized it is not a problem. Rotate your head 90% to the right or left and the screen will turn black. You can more easily try this by putting on a pair of polarized sunglasses
and rotating your cell phone 90% and watch the screen go black. If the vehicle you drive or fly has LCD screens in them you need to make sure that polarized sunglasses do not turn the screens black. Not a serious problem, but one which you should be aware of.
Heads Up Displays
Heads up displays in airplanes and cars are a different matter. A heads up display function by reflecting light horizontally off the windshield glass. In this case polarized sunglasses will block the horizontally polarized light and the heads up display turns black. So if you drive a car or fly an airplane
with a heads up display you do not want to wear polarized sunglasses.
Another concern with LCD screens is eye strain. If you sit in front of a computer screen all day long it will strain your eyes and make them uncomfortable. One solution that we have found is to wear sunglasses when viewing your monitor. A pair of non-polarized sunglasses with amber, brown or yellow lenses will help block blue light and reduce eye strain. No matter what the case you should always choose a quality pair of sunglasses. We are proud to offer a great selection of sunglasses in our shop
. Until next time keep your wings straight and level Hersch!