This is a great question emailed to us yesterday by one of our facebook fans. Polarized lenses present a great benefit to almost any person who finds themselves outside driving, playing sports, or just relaxing in the sun.
The technology behind how polarized lenses work is really interesting. Sunlight reflects from many 
surfaces, such as the water and the ground in a horizontal manner. This well organized horizontal reflection of light causes extremely annoying and potentially distracting glare to your eyes when outdoors, just as with this picture to the right.
But polarized lenses act as venetian blinds that filter out this horizontal reflection of light and allow only vertical refl
ections to pass through the lenses into your eyes. Look at the picture to the right that was taken through polarized lenses and compare that to the original above. This filtering out of the horizontal glare/reflection can create a drastic reduction in the amount of strain your eyes feel when outdoors.
While regular tinted lenses do filter out sunlight and reflections, they do so evenly. Regular tinted lenses do not filter out horizontal reflection differently than vertical reflections, so glare may surprisingly still be an issue. As a result, the best reduction of sunlight glare comes from polarized lenses. In our practice, our most popular demonstrator is a pair of glasses that has a regular tinted lens on one side and a polarized lens on the other. The difference is amazing.
Polarized sunglasses have been used for a number of years by fisherman and boaters to reduce the harsh reflections of the sun off the water. But really, anyone participating in outdoor activities from driving to golf to biking to sunbathing can benefit from this great technology. And the exciting part is that the technology has continued to improve to the point where polarized lenses can be integrated into most prescription lenses, including no-line bifocals (progressives).
They may be more noticeable when looking at bright lights or white backgrounds. These floaters are actually shadows cast on your retina by strands within a portion of your eye called the vitreous. The vitreous is a gel-like sphere that helps the eye maintain its shape, but over time the gel material starts to dissolve. As a result particles will be cast throughout the vitreous, and it’s these particles that cast the shadows onto the retina. While annoying, this is a normal aging process within the eye. However, caution should be used if simple floaters present more pronounced or if accompanied by other symptoms, such as flashes of light.
Over time, the same process that causes floaters also causes the vitreous to sink in on itself. Once the weight of the sinking vitreous becomes too great, it will detach from the retina. This is called a Posterior Vitreous Detachment and will cause more pronounced, darker and much more noticeable spots or floaters in the central part of your vision. The tugging force on the retina created by the detaching vitreous may even cause a person to experience flashes of light in their vision.