Photochromic lenses: Enhancing vision and comfort in changing light conditions
If you've ever walked outside only to grimace as the sun hit your eyes, you know that sunlight is no joke. Although we need sunshine to grow food, constant exposure to the sun's rays is bad for your skin and eyes. One way to protect yourself — besides investing in a sunscreen company — is to try photochromic lenses. These lenses protect your eyes from the sun's rays, making them an important addition to your wardrobe.
Understanding photochromic lenses
What are photochromic lenses?
Photochromic lenses, also known as light-responsive lenses, are lenses that get darker when exposed to ultraviolet (UV) light. Ever seen someone who wears glasses walk outside and then it looks like they’re wearing sunglasses? They have photochromic lenses. Although Corning initially developed the technology in 1966, the photochromic lenses you can buy today are much more advanced. Each lens contains specialized molecules designed to absorb UV light, ensuring your comfort under almost any conditions.
Benefits of photochromic lenses
One of the main benefits of wearing photochromic lenses is that you don't have to switch between sunglasses and regular glasses. If you're running errands on a sunny day, the lenses stay dark while you're walking down the street or standing in line at a taco truck.
Mmmmm. Tacos.
When you go indoors to drop off your dry cleaning or shop for a killer pair of jeans, the lenses get light again. There's no need to keep a pair of sunglasses on the top of your head or walk around squinting because you don't want to juggle a second pair of lenses.
Photochromic lenses also shield you from glare and protect your eyes against harmful UV rays. With prolonged exposure to UV rays, it's possible for some of the proteins in your eyes to harden, increasing the risk of cataracts. UV exposure may also worsen your sight, so it's important to protect your eyes at every opportunity.
How photochromic lenses work
Mechanism of photochromic lenses
If you slept through your high school chemistry class, you may have missed the lesson on how certain chemicals react to light. When exposed to UV rays, the materials embedded in photochromic lenses go through a chemical reaction that allows them to absorb light particles. It's like a lab experiment taking place right in your glasses.
Photochromic lenses usually contain microcrystalline silver chloride. "Micro" means the molecules are so small that you can't see them without a microscope. When the molecules come into contact with UV light, they start moving around. This causes them to change shape, making them capable of light absorption.
Light adaption range
These specialized lenses get lighter or darker based on UV intensity. But how do they know when to change? Every light wave has a frequency determined by how many wavelengths go through a fixed point in one second. Visible light, such as the light produced by a fluorescent bulb, usually has a medium frequency.
UV light has a higher frequency than visible light, which triggers photochromic lenses to darken. When you go indoors, the molecules inside the lenses adapt to changing light conditions, causing them to get lighter.
Choosing and caring for photochromic lenses
Lens options and customizations
Like music playback technology and most furniture, photochromic lenses have come a long way since the 1960s. Although you can still get glass lenses, many people choose polycarbonate instead. Polycarbonate is lighter than glass, but it's also much stronger, making it less likely to shatter. Think of glass as Bruce Banner and polycarbonate as the Incredible Hulk. Both are great guys, but the Hulk is much stronger.
Once you choose a base material, there are single-vision lenses and progressive lenses. Single-vision lenses are designed for one angle of view, while progressive lenses are designed for both distance vision and reading. Progressive lenses are helpful if you're over 40, as you may start to notice some blurriness while doing close-up activities.
Photochromic lenses come in several colors, giving you nearly limitless customization options. Take a walk on the wild side with orange lenses, stick with something neutral, such as gray, or go with the color of your favorite sports team. You can even add an anti-glare coating to give yourself even more protection.
Proper care and maintenance
When it comes to battling UV light, a good offense is the best defense. Once you have photochromic lenses, you need to care for them properly, which means cleaning them daily with lukewarm water and a soft optical cloth. You can even add a little dish detergent — just a drop — if they need a good cleaning.
Chemicals don't just react to light; they also react to temperature. Therefore, it's important to keep your photochromic lenses out of extreme heat and cold. When exposed to extreme temperatures, the lenses may not absorb as much light as usual, leaving your eyes with less protection.
Step into the light with confidence
You only get one set of eyes, so it's important to treat them with care. Photochromic lenses protect you from harmful UV rays and make it easier to see in all types of lighting conditions. Or, if contact lenses are more your speed, many of them have UV protection as well. You can find contact lenses at 1-800 Contacts (hey! That’s us!)
FAQs
Do photochromic lenses work in the car?
Although photochromic lenses have many benefits, they don't work in the car. This is because they only get dark when exposed to UV light. Your vehicle has a windshield designed to block UV rays, which means photochromic lenses won't darken while you're driving or riding as a passenger.
Can photochromic lenses be used as sunglasses?
You can use photochromic lenses as sunglasses under most conditions. After all, the main benefit of wearing these lenses is that you don't have to keep two pairs of eyewear with you at all times. The exception is if you're driving or riding in a vehicle. Photochromic lenses don't darken unless they're exposed to UV light, but vehicle windshields are designed to block UV rays. Therefore, it's helpful to keep a pair of sunnies in your glove box or center console.
Do photochromic lenses protect against blue light?
Yes. The materials embedded in photochromic lenses produce a yellow filter. Even though you can't see it, this filter cuts through blue light, reducing the risk of eye strain. This filter works even when you're indoors and the lenses aren't blocking any UV light.
Can I wear photochromic lenses while playing sports or exercising?
Absolutely. Photochromic lenses are ideal for outdoor recreation, as they adapt to changing lighting conditions. You won't have to worry about missing a goal because the sun is obscuring your vision. Look for polycarbonate lenses designed to withstand tougher-than-normal conditions. Contact lenses are also a great option for active people.