What are polarized lenses?
Polarized lenses are sunglass lenses with a special filter that blocks horizontal glare. *
Glare is intensely bright light that interferes with vision. Glare occurs when light waves are reflected off flat, shiny surfaces. Once reflected, the light waves become polarized and vibrate in a horizontal direction.
How polarized lenses work
To filter polarized light, we place a long chain of molecules (hydrocarbons) onto a thin film of polyvinyl acetate (PVA). The film is then heated and stretched, forcing the molecules to align end to end, or become polarized.
The film is then dipped into a solution containing a conducting molecule (e.g., iodine). These conducting molecules are now aligned along a pole (polarized) creating a microscopic grid of dark parallel lines that block light waves traveling along a plane that is perpendicular to their length. The film is cut into discs that are molded into the lens with the polarized molecule chains oriented vertically.
Outdoors, as light waves travel away from their source, they vibrate in all directions equally. This is similar to the way motion waves roll down a whip. But rather than the wave traveling on a flat plane it travels in all directions. When reflected off a flat, shiny surface, the light waves become polarized and align in a side-to-side, horizontal direction. The result is blinding glare.
Polarized lenses are like a fence when the whip is fed between the slats of a fence. Only the up and down waves can get through. The side-to-side waves would be blocked. A polarized filter blocks reflected glare in the same way. The horizontal waves are blocked.
* The amount of glare blocked by a polarized lens may vary by manufacturer.
What are polarized lenses?
Polarized lenses are sunglass lenses with a special filter that blocks horizontal glare. *
Glare is intensely bright light that interferes with vision. Glare occurs when light waves are reflected off flat, shiny surfaces. Once reflected, the light waves become polarized and vibrate in a horizontal direction.
How polarized lenses work
To filter polarized light, we place a long chain of molecules (hydrocarbons) onto a thin film of polyvinyl acetate (PVA). The film is then heated and stretched, forcing the molecules to align end to end, or become polarized.
The film is then dipped into a solution containing a conducting molecule (e.g., iodine). These conducting molecules are now aligned along a pole (polarized) creating a microscopic grid of dark parallel lines that block light waves traveling along a plane that is perpendicular to their length. The film is cut into discs that are molded into the lens with the polarized molecule chains oriented vertically.
Outdoors, as light waves travel away from their source, they vibrate in all directions equally. This is similar to the way motion waves roll down a whip. But rather than the wave traveling on a flat plane it travels in all directions. When reflected off a flat, shiny surface, the light waves become polarized and align in a side-to-side, horizontal direction. The result is blinding glare.
Polarized lenses are like a fence when the whip is fed between the slats of a fence. Only the up and down waves can get through. The side-to-side waves would be blocked. A polarized filter blocks reflected glare in the same way. The horizontal waves are blocked.
* The amount of glare blocked by a polarized lens may vary by manufacturer.