With the arrival of summer and its long, sunny days, we'll be spending more time outdoors. Whether you're at the park, the beach, or just taking a walk, it's important to protect your eyes from the sun's harmful rays. Sunglasses prevent the sun from causing permanent damage to your eyes by blocking certain wavelengths of light from entering your eyes. They have many properties, including reducing the amount of light reaching your eyes, protecting your eyes from harmful UV rays, reducing glare, and increasing contrast.
For this reason, we urge everyone to wear sunglasses, also known as light-absorbing lenses, when outdoors, especially when spending long periods of time in the hot summer sun. However, even on cloudy days, UV rays are present and it's best to wear sunglasses. It's also important to wear a wide-brimmed hat or sun hat to protect your eyes from the sun. Wearing a hat and sunglasses can reduce UV exposure by 30%.
This is especially important for people with impaired vision. If you have conditions such as glaucoma, diabetic eye disease, or retinitis pigmentosa, reducing glare and/or maximizing contrast are key to maintaining optimal vision every day.
People who spend a lot of time in the sun during the summer are at higher risk for developing age-related eye diseases, such as macular degeneration, later in life. In addition, prolonged exposure to UV rays can lead to other eye diseases, including cataracts and corneal problems. According to the National Eye Institute, an estimated 20% of cataract cases are caused by prolonged exposure to UV rays.
Sunglasses should absorb 99% to 100% of UV-A and UV-B rays and provide 400% UV protection. The best lenses for you depend more on your daily activities or "visual function" than on the condition of your eyes. Protecting your eyes from the sun is especially important for people who play outdoor sports and for infants.
When choosing sunglasses, keep the following in mind to protect your vision:
Dark lenses do not necessarily have UV protection. The key feature is whether the lens absorbs 99% to 100% of UV rays, especially UB-B. Any lens can be coated with a UV protection coating, regardless of the color. However, the coating does not block as much UV rays as a protective lens.
When shopping for sunglasses, look for ones made by a reputable optical manufacturer and labeled as blocking UVA and UVB.
The best protection comes from polycarbonate lenses, which are impact-resistant (so the lenses won't shatter and damage your eyes) and block both UVA and UVB rays. Polycarbonate lenses are only available through vision care professionals.
When playing sports, wear safety sports glasses with polycarbonate lenses for UVA and UVB protection and protection from balls, bats, and other potential hazards.
Whether you have vision problems or not, you may have trouble adjusting to sudden changes in light, such as when you enter a movie theater. Wearing sunglasses outdoors will help reduce the adjustment time indoors. For people with vision impairments, it can take anywhere from 5 to 30 minutes to adjust to light changes without sunglasses.
If you have vision impairments, talk to your eye care professional or low vision specialist (optometrist or ophthalmologist) about which sunglasses will best suit your needs. Absorbent lenses (sunglasses) come in a variety of tints and with varying degrees of light transmission.
Types of absorbent lenses include:
Wraparound: These plastic lenses fit over prescription glasses. Close-fitting, wraparound glasses are the best choice. They are available in a variety of colors and transmittances and have built-in side shields and a top edge to prevent light from entering the eyes. Most of these glasses offer adequate UV protection, but be sure to check to make sure. Glasses that are loose and/or don't wrap around the head will still allow light to enter through the open side of the glasses.
Photochromic/tinted lenses: These lenses darken in sunlight and can be used in conjunction with eyeglass lenses. Standard versions are available in both plastic and glass. Patients with low vision may be prescribed specialized photochromic lenses that block light below a certain wavelength. These lenses are available in specific colors and only in glass.
Polarized lenses: These lenses prevent light that reflects off smooth surfaces and causes glare from getting through. They are useful outdoors, near water, in the snow, or when driving. Some wraparound lenses are polarized.
Tinted: Tinted lenses come in a variety of colors and transmittances. While tinted lenses are useful, they may not be right for everyone. Coverall lenses and specialized photochromic lenses can provide unique solutions beyond just tinting a pair of glasses.
