What Are Polarized Lenses?

Polarized lensesare colored lenses used in sunglasses to reduce glare from reflective flat surfaces like water, glass, and wet roads. This feat is accomplished through a process called polarization, much like a Venetian blind controls sunlight through a window. Sunlight itself is not polarized – light from the sun will either be absorbed or reflected horizontally, diagonally, or vertically. The problem this causes for car drivers and water enthusiasts lies in horizontal reflectivity. Sunlight bouncing off a horizontal surface will strike the viewer’s eyes at a similar angle. This means the glare from the surface of the water, road, or car hood will be strong. Polarized lenses have a laminated surface containing vertical stripes. These stripes only allow vertically-polarized light to enter the wearer’s eyes. The glare is eliminated because the horizontally-polarized light waves cannot bypass the polarized filter.

Polarized lenses can reduce those pesky bright reflections of the sun on the cars ahead of you a great deal. Again, the assistance provided by polarization is a product of how the reflections tend to be horizontally polarized, thus perfect for vertically polarized sunglasses. The surfaces of the car in front of you (back window, trunk, and roof) will be slanted towards you, while the sun will be aligned in the vertical plane through both cars. In other words, polarized lenses are very helpful in sunny driving conditions.

Yes. It is worth noting that many of the cool devices we are now using (cell phones, GPS) are polarized and so when using your polarized sunglasses you will have reduced screen visibility. This is also true of LCDs, liquid crystal displays, found on the dashboards of some cars or in other places such as the digital screens on ATMs.