Important considerations when choosing sunglasses
You’ve been thinking about buying new sunglasses, but the options are dizzying. There are so many frame choices, and so many types of lenses. And what about UV protection, coatings, polarization and tints?
Style is a very personal choice. This guide won’t help you pick that perfect frame, but it can help you understand some of the options available to you when you’re shopping for new sunglasses. And you’ll find out how to care for them once you’ve made your choice. Let’s get started.
Why your eyes need sun protection
The single most important reason to wear sunglasses is to protect your eyes from the sun’s ultraviolet (UV) rays. Long-term exposure to UV rays has been linked to the development of serious eye issues, including macular degeneration and cataracts.
Protecting your eyes from the sun’s damaging rays is essential. To do so, wear sunglasses that block nearly 100% of UVA and UVB rays (also called UV 400 protection) when you are outside during the day. Even when the skies are cloudy, it’s important to wear sunglasses. You can’t depend on the clouds to stop the UV rays from getting through.
Three forms of harmful UV radiation
Three types of UV radiation can damage your eyes. Each form has different characteristics and potential effects:
UVC rays
UVC rays pack the highest amount of energy and present the most danger to your eyes. Luckily, the Earth’s ozone layer prevents the majority of UVC rays from reaching its surface. However, you can still be exposed to UVC radiation through artificial sources, such as germicidal lamps and certain lasers.
UVB rays
Some of the lower-energy UVB rays are also filtered by the atmosphere’s ozone layer. However, other UVB rays do get through. UVB radiation exposure is linked to several eye conditions, including photokeratitis (snow blindness), pterygium (surfer’s eye) and pinguecula.
UVA rays
Of the three types of UV rays, UVA rays contain the lowest amount of energy. However, UVA rays can travel through your cornea to reach the natural crystalline lens, and a small amount may potentially reach the retina at the back of your eye. In addition, excess UVA radiation is connected to the emergence of specific forms of cataracts and may play a role in other eye conditions.
UV radiation risk factors
Spending time outdoors puts you at risk of UV radiation-related eye conditions. However, your actual UV radiation dose depends on several factors, including:
- Geographic area – If you’re in a tropical region close to the Earth’s equator, you’ll receive a greater amount of UV exposure. As you get farther away from the equator, your risk decreases.
- Altitude above the Earth – You’ll be exposed to more UV exposure at higher altitudes.
- Specific setting – In expansive open spaces, you may receive more UV exposure. This exposure is especially likely when you’re in proximity to sand, snow and other reflective surfaces. To illustrate, UV rays reflected off the snow can almost double your exposure.
- Time of the day (and year) – When the sun is at its highest daily position, you’ll receive more UV exposure. This time generally occurs from 10:00 a.m. to 4:00 p.m.
- Prescription medications – Several types of medications can heighten your sensitivity to UV radiation’s effects. Examples include sulfa drugs, diuretics, birth control pills, tetracycline and tranquilizers.
Buying tips from the experts
When you’re shopping for sunglasses, ensure that you choose a pair that provides excellent eye protection. To that end, follow these four tips from the American Optometric Association:
- Buy sunglasses that filter out 99% to 100% of UVA and UVB rays. Also, make sure that your sunglasses prevent 75% to 90% of visible light from reaching your eyes.
- If you wear contact lenses, know that only some types contain any degree of UV protection. Even while wearing your contacts, you’ll still need sunglasses to shield your eyes.
- Your sunglasses should follow your facial contours and should be situated close to your eyes. Well-fitting sunglasses should help protect your eyes from all sides.
- Choose lenses with exactly matched colors. Also, ensure that the lenses don’t have any imperfections or distortions.
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Sunglasses design and construction
When you go pick out a new pair of sunglasses, you’ll have a lot of options. The brand and the style of the frame are just the first of several choices you can make.
Frame construction
High-quality sunglass frames are often made from durable, commonly available materials. Lightweight plastic frames are less likely to slide down your face, and they are well-suited to different types of lenses. Metal frames can add a distinctive touch to wire-rimmed sunglasses.
Lens types
If you’re in the market for quality sunglasses, you may have already made your sunglass frames selection. To determine which lenses are right for you, your eye doctor can conduct a thorough eye exam.
Prescription sunglasses
If you don’t have 20/20 vision, prescription sunglasses present a stylish solution that combines vision correction with protection from the sun. An optometric lab will fabricate the glasses using your chosen frame style and the prescription information from your eye exam. When delivered, your prescription sunglasses can provide an eyewear solution along with an impressive fashion statement.
Non-prescription sunglasses
If you don’t need vision correction, you’re a candidate for non-prescription sunglasses. Also called plano sunglasses, these shades aren’t used to correct your vision.
However, wearing plano sunglasses is a great way to keep your eyes safe from the sun’s harmful rays while accessorizing your wardrobe. Choose a style that complements the shape of your face, fits your lifestyle and matches your personality.
If fashion isn’t your priority, you may need sunglasses to enhance your performance in a specific sport. For example, a championship golfer may opt for eyewear that helps them see light and dark patterns in the grass to read the green better on a long putt.
Plano sunglasses are sold almost anywhere you go, from the convenience store down the street to massive online retailers and your local optometrist. Prices range from a few dollars for a generic pair to hundreds of dollars for exclusive designer sunglasses. The choices are nearly endless. Whichever sunglasses you choose, just make sure they have 100% UVA and UVB (or UV 400) protection.
Lens materials and treatments
Most eyewear manufacturers offer several different types of lens materials, each with its own characteristics. In many cases, you can add additional coatings or treatments to address certain limitations of a lens material.
Glass lenses
Relatively thick, heavy glass lenses deliver high-level optical clarity. They’re also resistant to scratches. However, glass lenses can easily shatter or chip. They also require an extra coating to reach the 100% UV protection threshold.
High-index plastic lenses
These high-tech lenses are very lightweight and often thinner than comparable glass lenses. Some high-index lenses have 100% UV protection built in, but it may need to be added for those that don’t. Because the lens material is relatively soft and very reflective, scratch-resistant and anti-reflective coatings may be recommended.
Polycarbonate lenses
Highly impact-resistant polycarbonate lenses are 100% UV protective, and they’re lighter and thinner than most other lens types. However, polycarbonate lenses scratch easily and typically require a scratch-resistant coating. They can also benefit from an anti-reflective coating.
Polarized lenses
By minimizing light reflection and glare, polarized sunglasses make colors appear brighter and more saturated. They can also make it easier to see objects below the surface of a lake, stream or other body of water.
The optometric lab can add polarization to the lens during the fabrication process. Note that polarized sunglasses can interfere with viewing LCD screens like those on many car instrument panels and smartphones. They are also not recommended when you are navigating icy roads.
Lens coatings
Sunglass lenses are frequently treated with one or more special lens coatings, such as:
- UV coating – Glass and plastic lenses often have a UV coating. This extra layer helps prevent the sun’s damaging rays from reaching your eyes.
- Anti-reflective coating – This coating is affixed to the surfaces of the lenses. It helps prevent light from reflecting off the back surface of the lenses and into your eyes.
- Scratch-resistant coating – A scratch-resistant coating aims to prevent scratches from damaging delicate sunglass lenses. This coating is typically applied to both sides of the lenses and is especially important for easily scratched materials, such as polycarbonate and high-index plastic.
Lens color
The color of the lenses is one of the primary characteristics of sunglasses. While certain tints are recommended for particular activities, lens color is mostly a personal preference and doesn’t affect how well the sunglasses protect your eyes from UV rays.
Other than just liking the way you look in red (or blue or orange) lenses, why should you choose one color over another? Here are the most common lens colors and why you might pick one over another:
- Gray – The most neutral tint, allowing for true color perception. It’s ideal for most activities.
- Green – Provides contrast and helps reduce glare. It’s ideal for activities like golf, tennis and everyday use.
- Red or rose – Enhance detail and depth perception. These tints work well for driving, cycling and snow sports.
- Blue or purple – Enhance color perception. These tints are ideal for outdoor activities and work well in foggy weather.
- Amber or brown – Increase contrast and heighten depth perception. These tints are ideal for many outdoor sports since they improve contrast against green grass and blue skies.
- Yellow, orange or gold – Improve visibility of objects in low-light conditions. They can be an excellent option for both indoor and outdoor activities.
Mirrored lenses
Another option you’ll have when buying sunglasses is a mirrored lens. Mirrored lenses have a very thin coating that reflects light. Silvered aviator sunglasses are the classic example.
Today, you have a lot more choices than just silver, including blue, orange, red, green and more and — in some cases — gradients between two or more of these colors.
Mirrored lenses, especially bold colors and gradients, are primarily a style choice. They have a huge “cool” factor, no question, but they’re practical as well.
Privacy is another reason mirrored lenses are popular. They’re more opaque than standard sunglass lenses, so they can lend a little additional anonymity.
Taking care of your sunglasses
To keep your sunglasses in good condition for years to come, it’s important to keep them clean, protected and in proper repair.
Keep them clean
- Rinse them with water to remove dust.
- Lightly rub a drop of no-lotion dishwashing liquid on the lenses and all parts of the frames.
- Thoroughly rinse to remove all the dish soap.
- Dry the sunglasses with a clean, lint-free towel.
- Use a clean microfiber cloth to remove any remaining smudges.
When you’re on the go, clean your sunglasses with a microfiber cloth or disposable lens-cleaning wipe. Avoid cleaning your sunglasses with:
- Tissues
- Paper towels
- Terry cloth towels
- Shirt sleeves
There’s a strong chance that using any of these items will scratch your sunglass lenses, which could affect your ability to see through them clearly.
Keep an adequate supply of lens-cleaning wipes, lens cleaner spray and microfiber cloths on hand. Local drugstores and discount stores are likely to carry these eyeglass-cleaning supplies.
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On your face or in the case
When you’re not wearing your sunglasses, always store them in a protective, hard-shell sunglasses case. This practice can significantly reduce the risk of damage and help ensure that you get years of service from your quality eyewear.
If there’s a bend or a scratch
If your sunglasses get scratched or the frames become damaged, it may be possible to fix them yourself, but that can also lead to further problems. In most cases, it’s best to consult an optical store or specialty repair professional who knows the brand and stocks the right replacement parts.
Start with an eye exam
Before purchasing sunglasses, schedule an eye exam with an eye doctor near you. You might be considering non-prescription sunglasses, but even though you may see well enough to pass a driver's vision screening without glasses, you might be able to see significantly better with prescription sunglasses. Only your eye doctor can tell you for sure.
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