Why do I feel blinded when looking at water, and wet or shiny surfaces on a sunny day?

When light is reflected off shiny horizontal surfaces – such as water, the road, wet surfaces, sand and snow – the light is transformed into polarized light and produces blinding glare. This blinding glare can obscure or completely block vision.

When light travels from the sun it does so in the form of waves that vibrate.  The light waves are unpolarized and travel in all directions – both horizontally and vertically. When these waves hit reflective horizontal surfaces, the surface absorbs only the vertical waves, while the horizontal waves bounce off the surface. This is the polarization of light. When the horizontal reflected light hits the eye, it causes blinding and often debilitating glare.

Only a polarized lens can remove blinding glare produced by horizontal polarized light. The difference between polarized and non-polarized lenses is how they handle glare, particularly the blinding glare from reflective surfaces.