Have you ever skipped stones off the surface of water at a local lake or river? Many children (and adults) find this simple task so much fun! You make it a competition involving the number of times your rock would skip before sinking, right? The good ones understand if a stone is horizontal or parallel to the water affects the ability of the rock to be able to skip off the surface more times or longer distances. That was the key to success when skipping stones.
The more vertical or perpendicular the stone is to the water, the more likely it will sink.
Light rays are reflected or absorbed based on the same principle.
From Skipping Stones to Understanding How Light Affects Your Eyes
Most people consider light rays as traveling in a straight line, but they actually spiral in a waveform. Sometimes the wave is horizontal and other times it is vertical. One can imagine the horizontal wave of light reflecting off of a surface much like a stone skips off the surface of water. This reflected light causes glare and visual discomfort.
How Do Polarized Lenses Help You See Better?
Polarized lenses are designed to block the horizontally oriented light while allowing the more vertically oriented light to pass through the lens. This technology gives our eyes the benefit of seeing the image without the accompanying reflections and glare our eyes would normally experience. At Academy Eye Associates, based in Durham and Chapel Hill NC, we almost always recommend polarized lenses.
What Are the Benefits of Polarized Glasses?
The most common example of the benefits of polarized sunglasses involves a fisherman who is able to see down into the water. The less light interference, the farther downstream one can see.
However, there are several other ways polarized sunglasses can be beneficial.
A car hood or asphalt road can be an extremely reflective surface, so for someone traveling, polarized lenses can greatly reduce eyestrain and fatigue, therefore reducing the chance of a headache or worse, falling asleep at the wheel.
Sometimes people confuse glare with brightness. Often, patients get a much darker tinted lens, but they actually could use a lighter tint with the benefit of polarization.
Polarized Sunglasses VS Transitions Vantage Lenses
Currently, there are two broad categories of polarized lenses. First, sunglasses can have polarized lenses. Second, Transitions Vantage lenses will change tint from light to dark depending on lighting conditions. These lenses are polarized, but the polarization only takes affect when the lenses are darkened.
Although most patients will benefit from polarized lenses, there are some situations where they may not be advantageous. Pilots rely on reflections to spot other aircrafts in the area so wearing polarized lenses could reduce their ability to notice their surroundings. Also, many planes are equipped with LCD’s (Liquid Crystal Displays). LCD’s usually emit polar light. Polar light means the light rays from the display are not a spiral, but instead they are only oriented at a certain angle. A keen observer will notice, if they are wearing polarized lenses, the LCD will “disappear” when they tilt their head.. This “disappearance” can be a major problem if a pilot is relying on instrumentation thousands of feet in the air. LCD’s are also found in car instrumentation. However, I personally wear polarized lenses when driving and the “disappearance” is rarely an issue.
All of that said, Summer is finally here! Enjoy the bright sunshine without the glare and eyestrain. Stop by and ask your Academy Eye Associates Optician about Polarized Sunglasses.