Polarization: why you need it.
Polarized goggles and glasses are becoming quite the rage. Why? Read on as we take you behind the ins and outs of polarization and explain why it may be beneficial to you.
Polarized Light: In un-polarized light, a photon of light has energy emitting (radiating) in random directions. There are numerous factors that can contribute to the polarization of light and those include; the scattering of light in the atmosphere, and reflection from linear surfaces such as water and highways. When this happens, the photons will lose some or all of their vertical or horizontal components. When the energy of the photons is aligned primarily in one direction or the other, the light is said to be “polarized” or “organized”. A good everyday example of organized light is an LCD (liquid crystal display). Depending on the way the light is organized, the display may or may not be viewable through polarized sunglasses or goggles.
Polarized filters: Polarized filters are made of molecules stretched into long strands and laminated between two sheets of either glass or plastic. Depending on whether the strands are aligned vertically or horizontally, light energy will be absorbed and no light will pass through. Filters aligned vertically will absorb polarized light aligned horizontally and the opposite applies to light aligned vertically.
Conventional vs. polarized lenses: Conventional non-polarized lenses rely on color density alone to reduce glare. Because polarized lenses have the ability to reduce the light energy by half without color density, they can be made with lighter color densities. This is one of the first things you experience with polarized lenses, they are comfortable to wear and they are not too dark.
Direct glare and reflected glare: Glare can be defined as “an uncomfortable sensation caused by bright light”. Conventional lenses can reduce the effects of direct glare as well as reflected glare. Polarized lenses however, can reduce direct glare and virtually eliminate reflected glare. This is because reflected glare is organized or “polarized light” and polarized lenses, as explained previously, will eliminate a photons horizontally aligned light segments such as those reflected from water, roads etc.
Polarization and Fishing: In most situations polarized lenses allow fisherman to see more clearly into the water. This is because light reflected off the water is blocked.
Polarization and Driving: Ever wonder why truck stops sell polarized sunglasses? This is because polarization does an excellent job of reducing reflected glare off the surface of the highway increasing perception and reducing eyestrain.
Polarization and skiing: Since sunlight can become polarized by atmospheric conditions such as dust, haze, rain or snow crystals. This can cause the sky to appear dull or washed out. When wearing polarized lenses either in goggles or glasses you will notice that the sky appears to be a much deeper blue. This phenomenon is at its peak in early morning or late afternoon.
Polarization and skiing myths: The single biggest myth about polarization and skiing is that you will not be able to see ice patches because the reflection off the ice will be blocked by the polarizing film. For a polarized lens to be the most effective, the sun will need to be at a roughly 45 degree angle directly in front of the person wearing the product. Since the majority of the ski areas and slopes in the northern hemisphere face north, the sun will be at the wearers back and reflected glare will not be an issue for a skier. If for some reason the skier was skiing in a southerly direction and the sun was directly in front of him, it is important to remember that the surface must be perpendicular to the alignment of the polarizing filter. Any tilt in the surface or the eyewear away from perpendicular and the filtering of reflected light is reduced. The bottom line is that for almost all circumstances, polarized lenses will contribute more to increased performance than that of a standard non-polarized lens.