Polarized Lenses Explained

RE: Polarized Lenses Explained

Former Member — Wed, 11 Jun 2014 07:06:52 GMT

A while ago I was shopping for polarized sunglasses. To reassure me that the sunglasses he was showing me was polarized, the seller put the sunglasses over a white paper; through the sunglasses I could see a black picture (a drawing of a woman) on the white background. When he put a different pair of sunglasses over it, I couldn't see any picture, only a blank white. He said the latter was not polarized. How does it work? The picture must have some special feature?

RE: Polarized Lenses Explained

Former Member — Mon, 19 Aug 2013 15:12:10 GMT

So the above quote "Like other high-quality sunglasses, polarized lenses also block 100 percent of the sun's harmful ultraviolet (UV) rays" merely refers to the underlined part above in your reply? I once bought a pair of interchangeable sunglass lenses. On the package it has "Polarized" but does not say it has UV protection. When I asked the salesman, he said if it's polarized then it has UV protection.Yes, polarized sunglasses use another layer to get UV protection. The polarization will block horizontally polarized photons, which includes visible light and UV, but will allow vertically polarized photons, including UV through. If your sunglasses were made by a reputable manufacturer, they will definitely have a UV layer.

RE: Polarized Lenses Explained

Former Member — Sat, 17 Aug 2013 05:19:22 GMT

UV protection is not related to lenses being polarized. Making a lens polarized doesn't give it UV protection but any manufacturer bothering to make polarized lenses would also give them UV protection. Polarized 3D glasses don't have UV protection so they shouldn't be worn outside. Most sunglasses have UV protection and even clear glass can be made to have UV protection. I know about this a bit as I have UV and CPL (circular polarizer) filters for my SLR camera. So the above quote "Like other high-quality sunglasses, polarized lenses also block 100 percent of the sun's harmful ultraviolet (UV) rays" merely refers to the underlined part above in your reply? I once bought a pair of interchangeable sunglass lenses. On the package it has "Polarized" but does not say it has UV protection. When I asked the salesman, he said if it's polarized then it has UV protection.

RE: Polarized Lenses Explained

Former Member — Fri, 16 Aug 2013 10:50:22 GMT

Is this another way to make sunglasses with UV-protection or the only way? UV protection is not related to lenses being polarized. Making a lens polarized doesn't give it UV protection but any manufacturer bothering to make polarized lenses would also give them UV protection. Polarized 3D glasses don't have UV protection so they shouldn't be worn outside. Most sunglasses have UV protection and even clear glass can be made to have UV protection. I know about this a bit as I have UV and CPL (circular polarizer) filters for my SLR camera.

RE: Polarized Lenses Explained

Former Member — Fri, 16 Aug 2013 09:28:28 GMT

Like other high-quality sunglasses, polarized lenses also block 100 percent of the sun's harmful ultraviolet (UV) rays, and they are available in a variety of tints and materials. Is this another way to make sunglasses with UV-protection or the only way?

RE: Polarized Lenses Explained

Former Member — Thu, 15 Aug 2013 14:57:58 GMT

You can also test your lenses with your computer LCD monitor. The monitor will become dark as you rotate your head if they are polarized. This is also how passive 3D TVs work. Odd lines and even lines have different polarization so your eyes see different images.

RE: Polarized Lenses Explained

orca1946 — Thu, 15 Aug 2013 12:57:54 GMT

I had explain to my wife that her bike computer did not need a new battery --- turn your head 90 & voila !! now she can see it. Thanx for an in depth explanation on the effect.

RE: Polarized Lenses Explained

JWAJack — Thu, 15 Aug 2013 06:18:38 GMT

I've found that goggles with polarized lenses are helpful for open water swimming because of their effect on the reflected glare. The goggles I've used were from Finis and Zoggs (the latter being photo-chromatic as well).