Fashion aside, sunglasses serve a true function — protecting eyes from the harmful rays produced by the sun. You're probably well aware of the need to protect your skin from the sun, but it's equally important to protect your eyes. Ultraviolet Light's Dangers Ultraviolet (UV) radiation consists of invisible rays from the sun. The three bands of UV light are: UVA, UVB and UVC. UVC rays are of little concern as they are absorbed by the upper atmosphere and do not reach the earth’s surface. UVB rays are the ones that burn the skin and can damage the eyes. Combined with cold wind and snow, UVB has the potential to cause snow blindness (photokeratitis), a temporary (lasting 12 to 48 hours) but painful problem in the cornea of the eye. Although not all experts and scientists agree, there is some research that suggests that daily exposure to UVB in very bright sunlight over a period of many years may cause cataracts, a gradual clouding of the lens of the eye. These two have the right idea about protecting their skin, but they're taking a big risk by not protecting their eyes with UV-blocking sunglasses! UVA rays are primarily absorbed within the lens of the human eye, though there are no documented disorders of the human eye from UVA. This, however, remains a much debated and researched topic, says the Sunglass Association of America (SAA).What to Look for When You're Buying Sunglasses Sunglass standards for lenses place limits solely on UVB and UVA rays, but bear in mind that both the standards and labeling are voluntary, not mandatory. According to these standards, sunglasses must block at least 70% of UVB and at least 60% of UVA.To best protect your eyes, look for sunglasses that provide at least 98% protection from both UVA and UVB rays. UVC rays are blocked automatically since they are absorbed in the atmosphere and do not reach the earth. Some of the higher-priced products with polycarbonate, glass or plastic (CR-39) lenses can claim to block 100% of the UV rays. Is It True That ... ? One question people ask frequently is whether pupil dilation from wearing sunglasses can cause problems for the eyes. The answer to this is that there is a very minimal dilation of the eyes when wearing Costa del Mar, Maui Jim, nyx golf.Sunglasses, Serengeti, polarized. sun protection and that the protection received from wearing sunglasses is greater even than simply standing in the shade. According to the SAA, sunglasses "reduce the UV more than if you were to stand in the shade, since the shade more or less evenly attenuates all wavelengths, visible and UV, while sunglasses preferentially attenuate shorter wavelengths (i.e., UV wavelengths)." Thus, sunglasses provide more protection. For years, polarized sunglasses have been used by boaters and fisherman to reduce glare from the water that they spend so much time on. In the past few years, however, the benefits of polarized sunglasses have been realized by a variety of other outdoor sports enthusiasts as well as by drivers and general use wearers as well. Thus, the popularity of polarized sunglasses has increased dramatically, as has availability.The activities that utilize the benefits of polarized sunglasses the most include, other than water sports, skiing, golfing, biking, and jogging. For these activities they offer a clearer view and eliminate glare.They are also recommended for driving in daylight and at night and in fact can reduce the glare that comes off a long, flat surface such as the hood of the car or a highway. Polarized sunglasses can also be used indoors by light-sensitive patients or by those exposed to bright light through windows.How Do Polarized Lenses Work? Light reflected from surfaces like a flat road or smooth water is generally horizontally polarized. This horizontally polarized light is blocked by the vertically oriented polarizers in the lenses. The result: a reduction in annoying and sometimes dangerous glare. There is some debate on the effects of polarized lenses on snow-covered surfaces. Some experts say they can reduce the intense glare that is caused by sunlight reflecting off snow. And some purport that the lenses are not satisfactory for sports such as downhill skiing because they may not provide the contrast the eye needs to distinguish ice patches or moguls.Additionally, polarized lenses may also react adversely with liquid crystal displays (LCDs) found on the dashboards of some cars or in other places such as the digital screens on automatic teller (bank) machines. The problem with LCDs is that when viewed through polarized lenses from a certain angle, they can be invisible.However, for most other sports and activities, polarized sunglasses can offer great advantages and benefits to the wearer. There are also many options available to the consumer in the types of polarized lenses on the market.Polarized lenses are great at reducing glare, as seen in this photo supplied by Serengeti. Polarized progressives are perfect for the presbyope who is also an outdoor sports aficionado. And polarized photochromic (that go from dark outside to light inside) lenses are right for the light-sensitive person who changes environments (inside to outside and vice versa) frequently.The bottom line is that whether you spend your time boating or waterskiing, in-line skating or mountain biking, driving at night or jogging at noon, polarized sunglasses are an excellent choice for sunwear.
Costa del Mar, Maui Jim, nyx golf.Sunglasses, Serengeti, polarized.
These two have the right idea about protecting their skin, but they're taking a big risk by not protecting their eyes with UV-blocking sunglasses! UVA rays are primarily absorbed within the lens of the human eye, though there are no documented disorders of the human eye from UVA. This, however, Costa del Mar, Maui Jim, nyx golf.Sunglasses, Serengeti, polarized.remains a much debated and researched topic, says the Sunglass Association of America (SAA).What to Look for When You're Buying Sunglasses Sunglass standards for lenses place limits solely on UVB and UVA rays, but bear in mind that both the standards and labeling are voluntary, not mandatory. According to these standards, sunglasses must block at least 70% of UVB and at least 60% of UVA.
Ultraviolet Light's Dangers Ultraviolet (UV) radiation consists of invisible rays from the sun. The three bands of UV light are: UVA, UVB and UVC. UVC rays are of little concern. Costa del Mar, Maui Jim, nyx golf.Sunglasses, Serengeti, polarized.UVB rays are the ones that burn the skin and can damage the eyes. Combined with cold wind and snow, UVB has the potential to cause snow blindness (photokeratitis), a temporary (lasting 12 to 48 hours) but painful problem in the cornea of the eye.
Serengeti, nyx golf, Maui Jim Sunglasses, polarized, Costa del Mar
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Sunglasses is giving away a free Maui Jim T-shirt with the purchase
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