Here is why pilots are not allowed to wear polarized sunglasses.
When you see a pilot walking around the airport, or get a glimpse of one on your flight, you'll notice that they absolutely love wearing Aviator sunglasses, it's just a part of the pilot swag! But, little did you know, those glasses are never fitted with polarized lenses – and for good reason.
First of all, we have to understand what polarized light is. The light emitted from the sun is made up of light particles, better known as photons. Photons are both a particle and a wave and, like other waves, they undulate both vertically and horizontally in straight lines. So, therefore, light emitted directly from the sun is unpolarized. The moment unpolarized light waves strike a non-metallic reflective surface such as the sea, a lake or even the clouds, the reflected photons take a wave path that is in the same direction, either horizontally or vertically, but not a combination of the two. Therefore, it becomes polarized.
There is a huge misconception in the name "polarized lenses" as these sunglass lenses don't polarize light at all, but rather block out polarized light from your vision.
You can test this out yourself by viewing a digital screen through a polarized pair of sunglasses. Digital screens are designed to emit polarized light so, if you view this through sunglasses that are designed to block out polarized light, and then rotate either the glasses or the device, it will eventually block out all light emitted by the screen.
This is exactly why pilot's don't wear polarized sunglasses, as they will not be able to see their cockpits digital instrument panels.
Take a look at the video below by YouTube channel: Captain Joe on Why PILOTS CAN´T wear POLARIZED sunglasses? Explain by CAPTAIN JOE