Polarised (or polarized) lenses are used in sunglasses to reduce glare from reflective surfaces such as the surface of water in a river or the bonnet of a car.
Sunlight is either absorbed or reflected horizontally, diagonally or vertically, and it is the horizontal reflections which causes problems (glare) for fishermen and drivers. Polarised lenses have a laminated surface containing vertical stripes, and these stripes allow only vertically-polarised light to enter the wearer's eyes (in much the same way that a Venetian blind filters sunlight through a window). Glare is eliminated because the horizontally-polarised lightwaves cannot bypass the filter, resulting in a fisherman being able to see fish below the surface of the water and a driver not being distracted by glare from his bonnet.
Along with fishing and driving, polarised lenses are useful in numerous other outdoor persuits - skiers, bikers, golfers and joggers are all likely to enjoy clearer vision in bright sunlight.
Some of the sunglass models on our website have polarised lenses as standard. We can fit polarised prescription sunglass lenses to many of the frames on our website, as well as to a customer's own frame (a reglaze). Please contact us for details.