Polarized sunglasses have been in use for decades and their history dates back to 1936 when Edwin Land first started using his patented filter to make them. Of course the early versions of polarized sunglasses were quite different in many ways from the sunglasses that we have today in terms of design and aesthetics but the underlying principles remain the same.
Polarized sunglasses for men and polarized sunglasses for women both work in the same way. Light from any natural source and most artificial ones too, will usually spread out from the source and move in all directions. However, when it hits and is reflected by a flat surface, the light then travels in one direction and this kind of light is said to have been polarized. This is the kind of light that you see when you look at a lake or an ocean. Polarization of the light usually results in reduced visibility- which, in the example of the lake, explains why it is difficult to see things at the bottom of the lake despite the fact that the water in the lake could be very clear.
The idea behind polarized sunglasses is to find a way to absorb the polarized horizontal light that is the cause of the problem but allow other light, particularly the vertical light, to pass through. This is done through a special polarization filter on the sunglasses which is created by applying a thin chemical film to the surface of the lenses. The non-polarized light that passes through the lenses now allows users to be able to see things more clearly without the glare that was being caused by the polarized light.
Polarized sunglasses, such as the polarized aviators, can be very useful in situations where the importance of perfect visibility is utmost. The polarization principles are not just restricted to sunglasses but are applied to other types of prescription spectacles as well.