How to Choose Sunglasses: Materials, Lenses and Frames Explained

Excessive UV exposure from the sun puts us at risk for a laundry list of issues, including skin cancer, the most common type of cancer in the U. S.¹ But what most people forget is the effect UV rays can have on our eyes. Forty-seven percent of people don't check the UV rating before purchasing sunglasses, even though UV exposure can cause eye growths, cataracts, sunburned eyes and eye cancer.²

Certain medications, Retin-A skin cream, cataracts and lighter-colored eyes (blue, hazel or green) can make you even more susceptible to UV damage, which means sun protection for your eyes isn't just optional — it is essential to protect this delicate organ.²

But with so many types of sunglasses and lenses on the market, how do you choose the best pair for your needs? Read on to find out.

Sunglass Lens Materials

Let's start with the differences in the materials lenses are made of.

• Glass: Though heavier and more expensive than other lenses, glass offers more scratch resistance and good optical clarity.
• Polyurethane: This lightweight material is a good choice for its flexibility, impact resistance and optical clarity, but is more expensive than other options.
• Polycarbonate: A popular option for its optical clarity and impact resistance while being lightweight and affordable, but it is less scratch resistant.
• Acrylic: The cheapest material that is less durable than others and may even distort your vision.³

3 Common Types of Sunglass Lenses

Regardless of which type of lens you choose, look for lenses with 99% UV protection or are labeled “UV absorption up to 400nm," which is the same as 100% UV protection.²

1. Polarized lenses

Polarized lenses are generally considered to be the most effective at reducing the glare from sunlight that bounces off surfaces such as pavement, water and glass. That being said, they don't work with tinted windshields and can create lower visibility, so if you have this problem with your windshield, you may want to try mirrored lenses. It's also important to note that reducing glare is not the same thing as UV protection, but it does help you see more clearly.

2. Photochromic lenses (also called transition lenses)

Photochromic lenses are two-tone sunglasses that get darker in bright light and lighter in low light, making them good for indoor and outdoor use.

Single gradient lenses are darker on top and lighter on the bottom, cutting light and glare from above but not below. This makes them good for driving or reading, but not for water and snow sports.

Double gradient lenses are dark on top and bottom but light in the middle, reducing glare from above and below but providing clear vision in the center. The downside is that these take longer to work in cold conditions, which isn't helpful if you're trying to protect your eyes from the snow's glare.⁴

3. Interchangeable lenses

Interchangeable lenses are removable lenses of different colors, so you can change them out depending on your activities and conditions.³

There are four types of coatings that can be applied to lenses for additional protection.

• Anti-reflective: Applied to the back of polarized or mirror-coated lenses to cut glare
• UV: Applied to plastic or glass lenses to add UV protection
• Mirror: Prevents light from penetrating the lens by reflecting it
• Scratch-resistance: Applied to both sides of the lens to protect from scratches⁵

What Is Visible Light Transmission (VLT)?

Visible Light Transmission (VLT) is a measure of how much light makes it through the lenses and to your eyes. It's important to pay attention to the VLT so you can find the right pair of sunglasses for the activities you plan to wear them for.

Looking at the chart below, you'll see that the brighter the conditions, the lower the VLT percentage, which offers you a higher level of protection from UV rays.³

VLT percentage chart

Sunglass Lens Color Options

Neither lens darkness nor color affects UV protection, but the darker the lens, the more light it blocks. Different lens colors filter light differently, affecting color perception and visual acuity.

• Gray: Good choice for outdoor activities, as it performs well in cloudy or sunny conditions and offer true color perception.
• Brown or Amber: Enhances contrast and is good for activities that rely on depth perception, such as golf or driving.
• Green: Great for all-purpose use and offers better contrast and color accuracy than other colors.
• Blue: Improves color perception and contours and reduces glare, so this color works well in snowy conditions.
• Yellow: Better contrast at dawn or dusk and in fog, haze and other low-light conditions, making it a great color for hunting, baseball and tennis, and are often preferred by pilots.
• Red or Pink: This shade is easy on the eyes (literally!), helping eyes adjust to contrast and making it a good choice for winter sports and driving visibility.⁶

How to Care for Sunglass Lenses

Proper cleaning of your lens will enhance the life of your sunglasses and help maintain any coatings that help reduce or eliminate glare and UV rays. Ideally, use a cleaning cloth specifically designed for sunglass lenses — never use paper products or tissues with added lotions or cleaners. Rinse your sunglasses daily with warm water (filtered tap water is best) and use mild liquid dish soap if needed. Do not use abrasive cleaners, soaps or detergents.⁷

Chemicals (from things like hair products, chlorine from swimming pools and glass cleaners) and salt water can damage your sunglasses, so always rinse them off after exposure to the above. Heat can also deteriorate your lenses or warp your frames, so avoid leaving your sunglasses in places with direct heat from the sun.⁷

Choosing the Best Frame for Your Face Shape

The most vital factor when choosing sunglasses is how much UV protection you get from them, but fashion and style are also important to many. Everyone's face and head sizes are different, so your best bet is to try before you buy.

Here are some general guidelines for different face shapes.

• Round: Frames with sharp angles — such as rectangular, square, cat-eye, wayfarer, oversized or shield — help balance your features.
• Square: Round frames — such as aviator, cat-eye, browline or oval — help with sharp features.
• Heart: Frames with broad lower rims — such as round, rectangular, wayfarer, geometric, butterfly or cat-eye — help elongate your face.
• Oblong or rectangular: Thick, angular frames — such as square, rectangle or wayfarer — help balance rounded features.
• Diamond: Choose frames that complement high cheekbones, such as oval, round, geometric or rimless.
• Oval: Just about any style will work for an oval face with balanced proportions.⁸

CareCredit Financing for Eyewear

Whether you're purchasing stylish new frames, getting contacts or due for an eye exam, the CareCredit credit card can help you pay for care where your insurance leaves off.* Apply today and use our Acceptance Locator to find a vision specialist near you that accepts CareCredit so you can see all that life has to offer. Continue your wellness journey by downloading the CareCredit Mobile App to manage your account, find a provider on the go, and easily access the Well U hub for more great articles, podcasts, and videos.

Author Bio

Abbie Mood is a freelance writer with more than 10 years of experience. She has worked with clients of all sizes to create compelling content and she has written for the American Kennel Club, Marriott Bonvoy, Women's Health Online, Headspace and more.