Polarized lenses have surpassed polycarbonate lenses as the fastest-growing category in lens sales. Today's polarized lenses come in a spectrum of possibilities. Not only are polarized lenses available in many styles from single vision to progressives, they now come in many different lens materials and colors, too. Even photochromics are now available in a polarized version.
How Do They Work:
Polarized lenses contain special horizontal polarizers or filters that help reduce glare off water and things such as paved roads. They also help enhance colors and vision in some high-glare situations. The lenses are invaluable in high-glare situations, such as driving, boating, golfing, surfing, and fishing. Polarized lenses also help reduce glare, which can be a real problem in water sports and many other outdoor activities.
Which Color Lens is Best?:
Some lens colors perform better than others, depending on lighting conditions and environment. For example, a dark gray tint works best for intense glare and bright sunlight encountered when driving, boating or deep-water fishing. Melanin and Brown C tints improve contrast and work well in bright conditions for golf, snowmobiling, and shallow water fishing. Green works well on bright days for tennis and baseball. Orange and yellow tints block blue light, and perform best under low-light or overcast conditions. These may be used for shooting, biking, and skiing. Red works well for low-light fishing, skiing, while violet or purple can be used for golf on overcast days.
Patients with macular degeneration (or at risk for it), should consider a Melanin tint. Melanin is a golden brown color that provides the most UV protection while maintaining true color balance.
Some polarized lenses can block the reflected light of LCDs, too. These are the lights in many dashboards, bank automated tellers, and other electronic devices. So, if you use a PDA, laptop, or have an electronic dashboard, you may want to check and make sure that the polarizing lenses you choose will not block out LCD light, too.
Receiving the right amount of light is critical to good vision, but exposure to the wrong type of light can result in serious long-term problems. Excessive exposure to ultraviolet (UV) wavelengths can cause eye conditions ranging from corneal burns (photokeratitis), growths on the conjunctiva (pterygium) and cataracts. UV is invisible, but that only makes it more harmful.
What is UV Radiation?:
Ultraviolet radiation is a part of the overall electromagnetic spectrum and is produced by sunlight, tungsten lamps, welding arcs, and certain types of fluorescent lights. It is classified into three categories: UVA, UVB, and UVC.
Fortunately, UVC (190nm to 280nm) wavelengths are absorbed by the ozone layer of the earth. These short, high-energy radiations can cause mutations in plants and animals. UVB wavelengths (280nm to 315nm) are also considered higher energy wavelengths and can cause sunburns, skin blistering, and skin cancer. This range of UV is why you wear sun block on a sunny day. The upper portion of this spectrum (from 300nm to 315nm) enters and affects the eye. UVA (315nm to 380nm) is the portion of the UV spectrum that is considered most harmful to the human eye because it is totally absorbed by the eye's crystalline lens.
Since the cornea transmits UV wavelengths from 300nm to 400nm, spectacle lenses should absorb these wavelengths for the patient to be protected from ultra-violet radiations. Armed with all the information on harmful UV, lens manufacturers have developed lenses made of materials that absorb these wavelengths without the need for added UV treatments. Remember, the American National Standards Institute (ANSI) requires that lenses classified as UV absorbing block 99.8% of UVB and 70% UVA.
Ultra-violet radiation may be harmful to the human eye, but with all the lens material options available today that absorb it, patients can easily get the protection they need simply by getting the appropriate lens recommendation. The right sunglasses protect the eyes from these damaging rays while still looking stylish and fashionable.
Watch the video for more information on sunglasses and polarized lens options. Remember, you don’t need an appointment to stop in and check out our sunwear!