Polarized sunglasses for outdoor activities
Polarized sunglasses were originally used to reduce reflected glare from the water in boating and fishing fields. With the development of polarized sunglasses, many others who participate in outdoor activities that require clear vision, such as skiers, bikers, golfers, joggers and so on are also interested in polarized sunglasses. Polarized sunglasses not only can reduce the glare from long, flat surfaces, but also are suitable for light-sensitive individuals working indoors, such as those continually being exposed to light throw windows.
Principle of polarization
How does a polarized lens work in reducing glare? In fact, reflected light travels in a more horizontal direction instead of scattering in all directions. This way causes dangerous light which we view as glare. A polarized lens contains special materials which can filter out this type of light and thus reduce glare. This process is formally called polarization. Remember that sunlight itself is not polarized. Drivers and fishermen will suffer from horizontal reflectivity because the sunlight is reflected horizontally by the flat surface near them. This kind of strong horizontal reflection is perceived by people nearby as glare. From another perspective, polarized sunglasses only allow vertically reflected light rays to enter the wearer’s eyes.
Advantage of polarized sunglasses
As mentioned before, the most meaningful advantage of polarized sunglasses is the capability of blocking out unwanted reflection or glare. Horizontally polarized light waves will be filtered out by polarized lenses. Many people can get great help from polarized sunglasses. In general, polarized sunglasses are the best choice when you want to enjoy outdoor activities, such as snow skiing, boating, in-line skating, mountain biking and so on. All of these activities or sports involve a smooth, flat surface that causes strong horizontal reflection.
Different types of polarized sunglasses
In addition, polarized lenses can be fitted into different types of sunglasses, which have other features that enable them to be suitable for particular groups of people. For instance, polarized bifocal sunglasses and progressive lenses are good choices for presbyope. It is undeniable that presbyopic folks also need the entertainment from certain sports. Another advanced type of sunglasses with polarized photochromic lenses that offer color switch in different light conditions is the favorable choice for light-sensitive individuals. This type of product just adds the polarization capability to photochromic lenses.
Disadvantages of polarized lenses in some special cases
Though polarized sunglasses provide a lot of advantages, such as comfort, glare reduction and so on, they are not perfect. For example, people may not want to filter the light reflected from icy patches during downhill skiing because low light can not send the message that they are approaching others. Furthermore, polarized lenses may also reduce the visibility of images appearing on the dashboards or other places because these images are created by liquid crystal displays (LCDs) and showed by digital screens. Another disadvantage of polarized lenses is the potential disability in seeing a cell phone or GPS device. This disadvantage may create a fatal consequence in some special conditions. For example, boaters or pilots may make a mistake once the decision they have made is strictly based on the information showed by digital screens.