When and How to Ensure Your Sunglasses Are Doing the Job?


It's a no-brainer to grab your sunglasses on a bright, sunny day, but what about the other moments? Surprisingly, statistics show that on cloudy days or during snowy spells, our sunglasses game takes a nosedive. In this post, we not only address why this is a concern but also guide you in evaluating whether your sunglasses are truly safeguarding your eyes.

Sunglasses for Glare Reduction

The journey of sunglasses began in the early 1920s, courtesy of British chemist Sir William Crookes. Introducing lenses that could block UV light with the help of cerium, his creation gained swift adoption among movie stars, sparking a surge in popularity.

Making their American debut in 1929, sunglasses took a new turn thanks to entrepreneur Sam Foster. Operating on the Atlantic City boardwalk, Foster revolutionized sunglasses by employing celluloid as the primary material, enabling mass production of these glare-reducing accessories.

In 1930, the U.S. Army unveiled aviator sunglasses for Army Air Corps pilots, sporting green-tinted lenses initially. Later, these were swapped for rose-colored lenses, recognized for superior protection against the sun's glare.

During this era, sunglasses weren't primarily bought for shielding eyes from damaging UV rays. Instead, people wore them for two reasons: to combat bright sunlight and to go incognito in public. Celebrities favored the latter, believing sunglasses aided in limiting fans' recognition.

In 1937, inventor Edwin H. Land, renowned for instant photography and the Polaroid system, introduced polarized lenses for sunglasses. Drawing on his experience in polarization from photography, Land perfected the technology to enhance eye protection from the sun's glare.

The Mechanism Behind Polarized Sunglasses

In the realm of polarized sunglasses, the original lenses sported a film adorned with millions of micrometer-sized polarized crystals perfectly aligned. Edwin H. Land ingeniously applied this crystal-infused film to sunglass lenses. The magic happened when these crystals skillfully redirected the glaring light away from the eyes.

Let's break it down: Without polarization, sunglasses serve to darken your view, offering relief from bright sunlight and sun glare. However, the real wizardry lies in polarization, where those tiny crystals work together to redirect and banish that pesky glare, providing a clearer and more comfortable vision.

With polarized sunglasses, the game changes. They skillfully deflect bright light off the lenses, offering a glare-free experience even in lighter-shaded glasses. Picture the sun's glare bouncing off a smooth lake or metal surface – polarized sunglasses work the same magic.

Land's genius invention saw widespread success during World War II. His polarized film became a crucial element in crafting dark-adaptation and anti-glare goggles, target finders, sunglasses, cameras, and more for soldiers.

In today's market, you still have the privilege of opting for polarized sunglasses, though they might require a bit of a search. These modern counterparts follow Land's legacy, featuring a chemical application that filters specific light waves. The result? A slightly darker image, but with crisper details, enhanced clarity, and a glare-free vision that Land would undoubtedly applaud.

Prioritize Broad-Spectrum UV Protection

Even in the early days of sunglasses, scientists were onto something with their concerns about UV exposure. However, it took a while for the general public to grasp the crucial importance of UV protection. 

Why the fuss? UV light packs more energy than regular light due to its shorter wavelengths. This heightened energy level makes it more adept at damaging human cells, both in the skin and the eyes. While we can see visible light, UV light remains invisible to the human eye – although some remarkable creatures, like bees, can perceive it. 

In essence, embracing sunglasses with broad-spectrum UV protection is not just a style choice; it's a smart move for safeguarding your eyes from the invisible yet potent threat of UV rays.

UV Radiation Comes In Three Distinct Categories: 

  • UV-A: Dominating 95 percent of UV rays reaching Earth's surface, UV-A penetrates deeply into the skin and eyes. It's the chief culprit behind tanning and accelerates the aging of the skin.

  • UV-B: The majority of UV-B rays are absorbed by the Earth's ozone layer, with only about 5 percent making it through. Despite its lower penetration compared to UV-A, UV-B is high-energy light that can damage skin cells, cause DNA mutations, and contribute to cataract formation.

  • UV-C: The most harmful rays, fortunately, are almost entirely absorbed by Earth's atmosphere.

According to the National Institutes of Health (NIH), UV exposure to the eyes has been linked to cataract formation and retinal degeneration, underlining the importance of protecting your eyes from these invisible threats.

Knowing When to Replace Your Sunglasses

Ever wondered if your sunglasses lose their UV protection over time? A study from Brazil suggests they might. Under controlled and intense exposure to UV light, researchers found that sunglasses' UV protection can gradually degrade. While further research is needed, the scientists recommended a cautious approach, suggesting that people consider replacing their sunglasses every two years.

So, when it comes to your shades, keep an eye out for signs of wear and tear, and if they've been your loyal companions for a couple of years, it might be time to bid them farewell and welcome a new pair for optimal eye protection.

The suggested two-year replacement timeframe for sunglasses hinges on the assumption of wearing them in direct sunlight for at least two hours daily. Realistically, not many people adhere to such consistent sun exposure, leaving the recommendation somewhat unclear.

Here's the lowdown: In many affordable sunglasses, UV protection is provided by a coating on the lens surface. Over time, wear and tear can lead to scratches and erosion of this coating, potentially allowing more UV radiation to reach your eyes. While the replacement guideline may be debatable, it underscores the importance of regularly assessing your sunglasses' condition and opting for a fresh pair if signs of wear emerge. After all, when it comes to eye protection, clarity is key.

In the realm of sunglasses, the ultimate goal is safeguarding your eyes. Consider the sun's rays as potentially harmful to your eyes as they are to your skin. The key takeaway? Embrace your sunglasses as an essential shield, donning them every time you step outside or bask in the sun's glow. When it comes to eye care, make protection a non-negotiable part of your outdoor routine. Your eyes will thank you for the shade and care they deserve.

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