The unpredictability of Victoria’s weather is well known, with locals and visitors alike consistently caught out by its ‘four-season days’. You know the ones that go from foggy and overcast to clear and warm, and back to windy and stormy?
Those days are hard enough to plan for without the added complication of managing prescription eyewear. Just wearing your glasses leaves you overexposed in the bright sunshine, and only having your sunglasses with you definitely won’t work. You could take both pairs, but this means more to carry, and you’ll still have to constantly switch between them throughout the day.
Photochromic sunglasses promise to solve this dilemma for you by rolling two pairs of glasses into one. With lenses that are clear in the shade and tinted in the sun, they offer the best of both worlds. But are they really the perfect solution?
The Case for Adaptivity
When you live in Geelong, there are many different ways you might spend an average day.
During the week, you might have to brave the commute along the Princes Freeway, battling both the traffic and the changing conditions. Or you might stay local, ducking in and out of your house or the office for meetings or other errands.
On the weekends, you could enjoy an easy stroll along the Waterfront, overcoming the glare to take in the view. Or you could treat yourself to a relaxing drive through the dappled light of the Otways.
However your day plays out, there’s likely to be a fair amount of strain on your eyes. They need to constantly adjust, your pupils continually dilating and constricting in response to the changing light. No wonder so many people end the day with sore eyes or a headache.
Traditional sunglasses can help prevent this, toning down the brightness and protecting your eyes against harmful UV rays. But they’re only as effective as how you use them, and keeping them on when you’re inside can actually add to your eye strain. So, you need to remember to take them on and off each time your environment or the conditions change.
Adaptive lenses, which transition from clear to tinted as required, can manage this process for you. By automatically responding to the amount of ambient sunlight, they can make sure your eyes are always suitably protected. They also take the effort and guesswork out of switching between your glasses and sunglasses.
The Evolution of Transition Lenses
If you’ve been wearing glasses for a while, you’re probably familiar with the concept of transition lenses. Depending on the strength of your prescription, they may have even been offered to you as an option. But, while convenience has always been a selling point, that came with a few important caveats.
Photochromic lenses were invented in the 1960s by Dr. William H. Armistead and Dr. Stanley Donald Stookey, scientists for Corning Glass Works. They discovered that adding silver halides, a key component of film emulsions, to glass lenses made them light-sensitive. This is because, when exposed to UV light, silver halide molecules change shape and absorb some of the visible light.
This was a real game-changer for optical lenses, though the public’s interest in the technology was initially quite limited. Photochromic lenses were expensive to produce and buy, so they were largely inaccessible to most people. As plastic lenses became more popular, the weight of the traditional glass lenses made them even less attractive.
This changed in the early 1990s, when plastic ‘transition lenses’ were first introduced. As they were significantly lighter, these lenses presented a genuine alternative to traditional clear lenses. However, adoption was initially slow, as many consumers felt that the performance of the first generation of transition lenses was subpar.
A second generation was soon released, which activated quicker and got much darker, and public interest in transition lenses grew rapidly. Since then, the technology has continued to improve, with modern photochromic sunglasses australia-wide reacting to both UV light and high-intensity visible light. This means they adapt to light changes even more quickly and are more effective in a wider range of real-world situations.
A Passive Safety Net
From sunburn and skin cancer to cataracts and macular degeneration, the dangers of prolonged sun exposure are well-known. As we experience some of the highest rates of UV radiation in the world, these are a particular risk here in Australia. Even on cool and cloudy days, UV levels here can reach 3+ (moderate and above), which are considered potentially harmful.
This highlights the importance of both skin and eye protection when spending any period of time outside. Photochromic sunglasses can help with this, ensuring you’re always covered, regardless of the weather and how it changes. There’s no need to switch glasses or remember your sunnies, as your lenses will automatically adjust to the conditions, keeping you safe and comfortable.
The Verdict on Photochromic Sunglasses
Photochromic lenses have long provided an undeniable level of convenience, but several notable limitations restricted their usability and popularity.
Early iterations were heavy, expensive, and not particularly stylish. As the technology developed, these issues were addressed, but some practical concerns remained, as several factors impacted their performance. Hot days yielded a weaker tint, and the UV protection provided by most windscreens rendered them largely ineffective when driving.
However, the newest generations of photochromic sunglasses provide an unparalleled combination of convenience, comfort, protection, and style. Now designed to respond to brightness and glare, as well as UV rays, they effortlessly adapt to even the most variable conditions. This makes them a great choice for a wide range of uses and lifestyles, ensuring your eyes always have the protection they need.
