Photochromic lenses have gained popularity as a convenient and practical solution for those seeking eyewear that adapts to different lighting conditions. These lenses automatically adjust their tint levels in response to the intensity of ultraviolet (UV) light, providing clear vision indoors and darkening outdoors to protect the eyes from glare and harmful UV rays. As with any technology, photochromic lenses come with their own set of advantages and drawbacks, making it essential to weigh the pros and cons before determining if they are the right choice for your eyewear needs. The convenience of photochromic lenses is a significant advantage for people who frequently transition between indoor and outdoor environments. With the ability to adjust their tint levels automatically, these lenses eliminate the need for multiple pairs of prescription glasses, saving both time and money. However, certain drawbacks need to be considered before committing to photochromic lenses. Pros of Photochromic Lenses Convenience and Versatility One of the main reasons people choose photochromic lenses is for their convenience and versatility. These adaptive lenses automatically adjust to the level of light, providing clear vision in all conditions. This eliminates the need for multiple pairs of eyeglasses or the hassle of switching between prescription eyeglasses and sunglasses when going from indoors to outdoors and vice versa. For those who require prescription lenses, photochromic lenses offer a simple all-in-one solution. UV Protection In addition to their convenience, photochromic lenses also provide excellent protection against harmful UV rays. The MaatOptical brand of photochromic lenses blocks of UVA and UVB rays, shielding your eyes from the potential dangers of long-term exposure to sunlight. This level of protection can help reduce the risk of eye conditions such as cataracts and macular degeneration. Eye Health Benefits Apart from UV protection, photochromic lenses offer various other eye health benefits. They provide visual comfort by automatically adjusting their tint according to the surrounding light conditions. This reduces eye strain and fatigue, making daily activities more comfortable. The adaptive nature of photochromic lenses also ensures improved vision in low-light conditions. Moreover, Maat's photochromic lenses offer the option to include blue light protection based on personal preference. By shielding eyes from excessive blue light exposure, photochromic lenses can further contribute to overall eye health and comfort. Photochromic lenses offer numerous benefits including: ● Convenience: No need to switch between prescription eyeglasses and sunglasses. ● Versatility: Suitable for both indoors and outdoors use. ● UV Protection: Blocks of UVA and UVB rays. ● Eye Health Benefits: Reduces eye strain, fatigue, and blue light exposure. Cons of Photochromic Lenses Performance in Vehicles One drawback of photochromic lenses is their performance in vehicles. They typically do not darken as much in a car since the vehicle's windows filter out UV rays，but they can filter out UV rays that car windows may miss and eliminate the need to switch glasses when leaving the vehicle. Adaptation to Changing Light Conditions Photochromic lenses can sometimes take some time to adjust to changing light conditions. They generally darken in bright light and lighten in low light environments, which can be a great benefit. However, they may not always adapt quickly enough when transitioning from bright sunlight to shade, or vice versa. This slow response time could be inconvenient for wearers, especially in situations where the light conditions change rapidly, such as when stepping indoors from bright sunshine. Cold weather can also slow down the darkening process, making them less ideal for winter sports enthusiasts. For this purpose, Maat Optical lenses with faster responsiveness are specifically designed to address this issue. Photochromic lenses remain clear indoors, while get dark outdoors when exposed to UV light present in sunlight. The major factor of the magic is the photochromic dyes in the lens or on the surface of the lens. After decades of R&D and improvement, Maat has made breakthrough achievements in its self-developed and improved dyes: 1. Faster responsiveness 2. Darkness up to CAT-3 level 3. Stability and consistency in all optional colors 4. Long-service life Maat Optical Super Darker & Faster Collection boasts remarkable statistics: Changing Speed +18.5%, Fading Speed +26%, Darkness +29.8%. Experience the Jelly Series for vibrant, optional colors, elevating your sense of fashion. Cost Considerations Finally, the cost of photochromic lenses may be a significant factor to consider when weighing the pros and cons. In conclusion, while photochromic lenses offer some advantages in terms of convenience and eye protection, they do have certain limitations. Consider factors such as performance in vehicles, adaptability to changing light conditions, and cost when deciding if these lenses are the right choice for you. Photochromic Lens Technologies Advancements in Photochromic Tech Maat currently adopts two kinds of production processes to meet the needs of different consumer groups. In-mass photochromic originally was developed by Corning in the 1960s and applied to glass materials, nowadays it is widely used in resin lens production. The principle is mixing photochromic dyes with lens monomer, the biggest advantage is a stable photochromic performance at a lower price, the bands are only mid-index available, and lower responsive speed(both darkening and fading time). CB layer coating photochromic, also named spin-photo, is considered to be the most advanced photochromic lens production technology nowadays. Advantages: faster color changing speeding and fading speed, more optional indexes andflexible function selection. Disadvantage: higher price. Progress in photochromic technologies ensures that users can enjoy the benefits of these versatile lenses without compromise. As technology continues to evolve, photochromic lenses will likely become even more effective and tailored to specific needs. Choosing the Right Photochromic Lense Lens Materials and Tints When selecting photochromic lenses, consider the lens material and tints. Common materials include glass lenses, polycarbonate, and high-index plastics, each with varying levels of UV and impact resistance, weight, and optical clarity. Consult an eye care professional to determine which material is right for your personal needs and prescription lenses requirements. Lens colors also play a role in defining the performance of photochromic lenses. Some lens colors, like gray or brown, provide more accurate color vision, while others offer more contrast. Consider your lifestyle and daily activities to choose the most suitable lens color for your needs. Lens Coatings and Features Photochromic lenses can come with various coatings and features that provide additional benefits. An anti-reflective coating reduces glare and enhances visual comfort, especially in low light or night-time activities. A blue light filter reduces exposure to harmful blue light emitted by digital devices and may help prevent digital eye strain. When opting for photochromic lenses, ensure these additional features align with your personal needs. For example, you may prioritize blue light protection if you spend a significant time in front of computer screens. Personal Optical Needs Lastly, consider your personal optical needs, including myopia, hyperopia, and reading requirements. If you need separate prescriptions for distance and reading, you may opt for bifocals or progressive lenses with photochromic features. If you have specific requirements for your frames or considering contact lenses, be sure to consult an eye doctor about the compatibility of photochromic technology with these options. By evaluating lens materials, coatings, features, and personal optical requirements, you can make an informed decision on choosing the right photochromic lenses tailored to your needs and lifestyle. Frequently Asked Questions Are Photochromic Lenses Suitable for All Ages? Photochromic lenses are a versatile choice that can benefit people of all ages. They automatically adjust to various lighting conditions, providing comfort and convenience for both children and adults. Seniors may also find them helpful, as their eyes become more sensitive to light with age. However, some individuals might prefer traditional prescription sunglasses, while others might not need the added convenience of light-changing lenses, so it ultimately depends on one's specific needs and preferences. How Long Do Photochromic Lenses Last? The lifespan of photochromic lenses can vary based on several factors, including the brand, lens material, and how well they are cared for. Generally, you can expect photochromic lenses to last about 2-3 years before they begin to lose their effectiveness in adapting to different light conditions. Additionally, exposure to extreme temperatures and frequent changes between indoor and outdoor environments can affect lens performance over time. To prolong the life of your photochromic lenses, follow proper care instructions, such as cleaning them regularly with a gentle solution and keeping them in a protective case when not in use. What are the benefits of using photochromic lenses in everyday eyewear? Photochromic lenses offer convenience by adjusting to different light conditions automatically. They protect your eyes from harmful UV rays and provide comfort by reducing eye strain in bright sunlight. Since they transition from clear to dark and back again, you won't need to carry a separate pair of sunglasses. Can photochromic lenses replace the need for separate prescription sunglasses? In many instances, photochromic lenses can replace the need for separate prescription sunglasses. They provide the versatility of having both clear glasses and sunglasses in one pair. However, some people may still prefer having dedicated sunglasses for specific purposes like outdoor sports or high-glare environments. Are there any specific situations where photochromic lenses may not perform optimally? Photochromic lenses may not perform optimally in certain situations, such as inside a vehicle. Car windshields typically filter out UV light, which may not trigger the lenses to darken. Extremely hot or cold temperatures can also affect their responsiveness. Additionally, some people with specific eye conditions might not benefit as much from the adaptive features of photochromic lenses.
Meta Description: Photochromic lenses don't get dark when used in cars due to the windshield technology. This post explains all you need to know about car windshield technology and your photochromic lens. Do Photochromic Lenses Work In A Car? Most Photochromic lenses do not darken inside cars. Therefore the simple answer is no. However, there are some exceptions that will be discussed later in this article. In order to understand why your photochromic lenses do not darken inside your car, we will start by explaining what a photochromic treatment does to your lenses. Photochromic lenses are made up of particles sensitive to ultraviolet rays, therefore, they darken or lighten depending on the amount of UV rays your lenses absorb. Thus; If you are in a closed space or with artificial light, your glasses will have “clear” lenses; if you go outside and are exposed to the Sun, they will darken to a deep hue in a short period of time. That said, photochromic lenses are not entirely recommended for driving since the windshields of most cars for a couple of years now have a UV light filter integrated from the factory to reduce glare for drivers on the road. How photochromic Glasses work in the Car Your windshield is normally very different from the rest of your glass, in that it is two laminated panes with a layer of plastic that contains UV light inhibitors that protect the plastic and therefore also prevent UV light transmission. A laminated glass windshield typically blocks 98 to 99% of all UV rays. Ultraviolet light operates under the visible spectrum and is invisible to the human eye. Its presence and effect have nothing to do with the luminosity of the sun; This is why you can still get sunburned if you go to bed on a cloudy day. This sometimes leads to confusion about the effectiveness of transition lenses and fuels questions such as; "If bright sunlight shines into my car, why don't my photochromic lenses darken? Are they defective? " No, your photochromic lenses work very well. They simply cannot react to a light source that is not present, and in a vehicle, most of that UV light has already been taken out of the equation. Additionally, the lenses transmit light at about 83% when indoors (without anti-reflective coating). ‘My Photochromic Lenses sometimes darken in the car and sometimes do not’ You may notice your lenses darkening in your car. This is because, in typical automotive vehicles, only the windshield blocks a high percentage of ultraviolet rays. Side and rear windows are rarely laminated. Therefore, although they have some anti-UV properties, they also allow a good portion of ultraviolet light to escape. And, of course, open windows allow certain amounts of ultraviolet light to filter in which can make your transition lenses react. How do I Use Photochromic Lenses while Driving Photochromic lenses are considered useless when driving during the day. This is because it doesn’t serve its purpose of blocking UV rays when inside the car as the windshield already does that. Therefore, If your prescription photochromic lenses don't darken enough for your comfort level in the car, you have options. You can purchase a pair of prescription sunglasses for driving. You can also purchase clip-on sunglasses to temporarily attach to your prescription glasses. How Can Photochromic Lenses Be Beneficial For Driving? If your windshield is defective or broken, it can impair its ability to block most UV rays from getting to your eyes. Therefore, you can use a photochromic lens in the meantime before you find a solution to your windshield. It’s not advisable to drive around with a defective windshield just because you have a photochromic lens though as there are other concerns. Photochromic lenses can also be beneficial if you love driving with your windows down. This can help prevent the adverse effects of UV rays when you look outside through your car window. Lastly, most people don’t know the amount of UV rays escaping through their windshield. Therefore, a photochromic lens can still be worn just in case. Photochromic lenses can also help to block blue light while driving, especially lenses produced by Maat Optical. In Conclusion Photochromic lenses have limited use when driving and may even be totally not needed. However, they can be used in some few conditions and can even be very beneficial in other situations. Therefore, the decision to use a photochromic lens while driving is an individual decision. If you would like a photochromic lens that works behind the wheel, consult Maat Optical. We have over 20 years of experience dedicated to satisfying the photochromic lens needs of all our customers. Photochromic lenses produced at Maat Optical have faster responsiveness, get dark up to CAT-3 levels, stability and consistency in all colors and a long lifespan. FAQS Are Photochromic Lenses Good For The Eyes? Photochromic lenses adapt to changing light, reduce glare and limit UV exposure, making them a great choice for eye protection. How Do Photochromic Lenses Work? Photochromic lenses contain special molecules called organic photochromic dyes. When exposed to ultraviolet (UV) light, these molecules undergo a chemical reaction, causing a change in the lens color. In the absence of UV light, the molecules are transparent. Upon UV exposure, they undergo a structural change, absorbing certain spectra and darkening the lens color. As light diminishes or UV light is no longer present, the molecules revert to their original state, gradually returning the lens to a transparent condition. This automatic adjustment feature allows photochromic lenses to provide appropriate sun protection under varying light conditions, offering comprehensive eye care.
Do photochromic lenses filter blue light? The simple answer to this is yes. Photochromic lenses are not designed for this purpose as they are designed to darken on exposure to sunlight and prevent your eyes from the harmful effect of Ultraviolet light. Most people buy Photochromic lenses because they don't want to continually switch between clear glasses and sunglasses when they move from indoors to bright sunlight. However, photochromic lenses also protect our eyes from the blue light from the sun as well as our digital devices thus preventing digital eye strain, mid-afternoon fatigue, headaches, and trouble sleeping. This may eliminate the need for further prescription glasses in some cases. Crazy right? Let's dive right into the fine details. What Are Blue Light Filter Lenses? If you are familiar with glasses and their treatment or you were one you have probably heard of ‘blue light filter.’ However, you may be wondering what they are. It is important to talk about the types of blue light before we discuss blue light filtering. There are two types of blue light which are: Blue light – turquoise: This is the type of blue light that is emitted from the sun and can even be beneficial for health, especially regulating the circadian rhythm. This is because it helps regulate our “biological clock” by suppressing the production of melatonin and influencing the production of serotonin, which promotes that feeling of well-being, and also the production of vitamin D in our body. Blue-violet light: On the other hand, blue-violet light is considered harmful to eye health, especially with prolonged exposure. It is usually emitted by artificial lights in our immediate surroundings as well as digital devices with screens. To prevent blue-violet light, which is harmful to the eye, lenses with a blue light filter are treated with a protective coating that can be used in prescription eyeglasses and sunglasses. It is important to note that only turquoise blue light—which is generally beneficial to body and visual health—is allowed to pass through this protection. Do Photochromic Lenses Block Light From Your Screens? Even though blue light and ultraviolet light rays aren't the same thing, blue light is just a level below UV rays on the light spectrum and thus can still be harmful to the eyes, especially with prolonged exposure to digital screens and direct sunlight. Any invisible and partially visible light can have side effects that are harmful to your eye health. While UV exposure can be avoided by staying inside or forgoing tanning beds, blue light is practically everywhere digital devices thrive. Our eyes are daily exposed to blue lights from Smartphones, Laptops, Tablets, Smart TVs, and much more. Although photochromic lenses were designed for a different purpose, they do indeed have blue light-filtering capabilities. Photochromic lenses generally provide protection against the highest energy level on the light spectrum (UV rays). While UV light and blue light are not the same thing, high-energy blue-violet light is next to UV light on the electromagnetic spectrum. This means that photochromic lenses can also protect against blue light and are excellent for computer use or use with other blue light-exposing digital devices. Side Effects Of Blue Light Blue light, emitted by the digital screens we use every day, not only causes eye strain which can lead to headaches and blurred vision but can also disrupt our sleep cycle according to studies. While blue light in small amounts may have positive effects, like helping you sleep better, most people don't moderate their screen time and therefore are at risk of side effects if prolonged exposure to blue light. Here is a complete list of blue light side effects: ●Macular degeneration: Blue light can cause retinal damage, which has been linked to macular degeneration, especially age-related macular degeneration.. ●Dry eyes: When you look at digital screens, which emit a lot of blue light, you blink less often (and even less if you wear contact lenses), which leads to insufficient moisture production in your eyes. ●Digital Eye Strain: Constant exposure to blue light can cause fatigue in your ciliary and extraocular muscles. ●Blurred vision: When your ciliary and extraocular muscles weaken, your vision can become blurry. Relaxation of these muscles is a side effect of digital eye strain, caused by blue light. ●Cataracts: You may have heard that sun exposure can lead to cataracts, but blue light also produces the same cells responsible for this debilitating eye condition. This is with prolonged exposure to blue light over the years without any protective eyewear. ●Headaches: Straining to see when your eyes are tired and your vision is blurry can also cause headaches. ●Insomnia: Do you take a long time to fall asleep after looking at your phone in bed for an extended period of time? Blue light may be responsible for your difficulty falling asleep. ●Restless sleep: Even if you fall asleep fairly quickly, blue light can deprive you of the vital rest that sleep should provide you. Should I Get Photochromic Lenses? While exposure to blue light (turquoise) is important for keeping our wellbeing, alertness, and cognitive performance during the day, chronic exposure to low‐intensity blue light directly before bedtime, may have serious implications on our circadian phase and sleep quality. This raises inevitably the need for solutions to improve well-being, alertness, and cognitive performance in today's modern society where exposure to blue light-emitting devices is ever-increasing. Photochromic lenses have many benefits, particularly because they function as both glasses and sunglasses as they darken when exposed to ultraviolet light from the sun and protect against UV rays In addition, we have shown that photochromic lenses filter blue light from digital screens and sunlight. By reducing the effects of glare and protecting your eyes from harmful overexposure to blue light, photochromic glasses can contribute to a more comfortable user experience. Do you want a reliable photochromic lens partner? Maat Optical has been dedicated to the art of producing photochromic lenses for more than 20 years and they are ready to satisfy all your wholesale photochromic lens needs.
The word ‘photochromic’ is coined from two Greek words: photos, meaning light and chroma, meaning color. Therefore, we can deduce that photochromic glasses can change their color when exposed to light. This is a very simplified definition of what photochromic sunglasses can do. This article explains what photochromic glasses are, how they work, and what materials are used in their production. What are Photochromic Glass Lenses and Sunglasses? First developed in the 1960s by the Corning Glass Works factory, photochromic glass lenses are coated with chemicals which make them darker when exposed to bright light and clear when in normal light. These lenses are called several names, including ‘light intelligent’ and ‘variable tint’ lenses. Photochromic lenses not only block light, but they also protect the eyes and their surrounding tissues from UVA and UVB rays. Photochromic eyewear comes in several forms, including contact lenses, prescribed eyeglasses, and sunglasses. Our focus here will be on photochromic sunglasses. Photochromic sunglasses are not as clear indoors as other photochromic eyepieces but get darker in the sun, blocking more light. How Photochromic Sunglasses Work A photochromic lens is usually coated or infused with organic and inorganic chemicals such as silver halide, pyrido-benzoxazines, and silver chloride. The molecules of these chemicals have a certain arrangement when under normal lighting conditions. When exposed to UV rays from the sun, these molecules move, rearrange themselves, absorb light, and the lens becomes darker as a result. Although photochromic sunglasses mainly shield our eyes from very strong light, most are sensitive to ultraviolet rays and not visible light. That is why most lenses typically do not darken inside a vehicle because the windshield only lets in visible light while blocking most UV rays. However, newer technology allows some lenses, like those used in Maat Optical sunglasses, to activate with visible and ultraviolet light. Recent advances in technology allow the addition of dyes to the coating materials, which lets you tint the eyeglasses according to your preferences. Photochromic lenses usually take around 30 seconds to darken when exposed to the sun and stay dark unless you move away from the bright area. It takes longer for the sunglasses to return to normal, typically around 2-5 minutes after leaving the sun. Environmental factors, such as temperature, can affect the time the lens takes to return to normal. Types of Photochromic Lenses Photochromic lenses were originally made with glass. However, the increased availability of other materials like resin or plastic has made the creation of sunglasses with other materials possible. Materials like plastics and resins are sometimes preferred to glass because they are more flexible and lighter in weight. Maat Optical sunglasses use glass and other high-quality materials so that you can make your choice based on your preferences. Glass Photochromic Lenses These are the original photochromic lenses. They use glass lenses coated with a photochromic chemical such as silver halide or silver chloride. Glass lenses are generally thinner and more attractive than plastic lenses because of their higher refracting indexes. However, they may be prone to producing glares. Glass lenses are more scratch-resistant than lens materials like plastics. The major disadvantage of glass lenses is their brittleness, which decreases their durability. Also, glass lenses have a limited option of frames compared to other materials. Plastic Photochromic Lenses Plastic photochromic lenses use carbon-based compounds called photochromic dyes. When exposed to ultraviolet light, these compounds change their structure to darken the lens. These compounds, such as pyrido-benzoxazines, react more quickly to UV light than those used in glass lenses. Plastic lenses are lighter than glass lenses, so they are more comfortable to wear and won’t slide down your nose easily. Plastic lenses are less prone to glare, more flexible and durable, and compatible with a wide range of frames. However, they are more prone to scratches and are usually thicker and less attractive than glass lenses. Tinted Photochromic Lenses The photochromic dyes used in plastic lenses can produce different colors or tints in sunglasses using plastic lenses. This gives you the flexibility to choose any color you like. The lenses can also be coated with an extra reflective compound, which offers more protection from UVA and UVB rays from the sun. Benefits of Photochromic Sunglasses UV Protection A lifetime exposure to UV radiation and sunlight has long been associated with cataracts in older people. Photochromic sunglasses can effectively prevent up to of these harmful rays from reaching the eye. Reduced Eye Strain By reducing the amount of light getting to the eyes, these sunglasses help reduce eye strain from bright sunlight. This leads to increased visual comfort when you’re outdoors. Convenience A photochromic sunglass is essentially two glasses in one: a pair of sunglasses in the sun and a normal pair of glasses in normal light. With these glasses, you need not worry about your itinerary because they work well indoors and outdoors. Cost-Effectiveness With photochromic glasses, you essentially get two pairs of glasses at a much lower price. Disadvantages of Photochromic Lenses Slower Response Time Photochromic glasses take some time to adapt to new lighting conditions. It can be faster to whip out a suitable pair of glasses instead. Higher Cost Photochromic sunglasses cost more than conventional sunglasses. However, they cost less than getting two pairs of eyeglasses. Temperature Sensitivity The change in the molecules’ positions is a chemical reaction affected by ambient temperature. Cold or hot temperatures can make the lens transition more slowly than normal. Not Safe for Driving Photochromic sunglasses get darker when they come in contact with sunlight. Therefore, they should not be used while driving. Conclusion Among the brands producing photochromic lenses, Maat Optical can be considered one of the best. Our line of photochromic sunglasses has been designed to satisfy all your needs in a perfect pair of eyeglasses, such as comfort, optimum vision, and protection throughout the day.
If you are not new to using glasses then you are probably familiar with photochromic lenses. They are designed to change their characteristics (color) to changing light conditions such as bright outdoor sunlight or lighter indoors. This singular characteristic makes them a top choice for people who do not want to switch between different pairs of glasses in changing light conditions. However, if you are new to glasses and stumbled on photochromic lenses you may be wondering if your glasses are made with photochromic lenses or not. In this blog, we'll explore different ways to activate the photochromic reaction that distinguishes photochromic lenses from other lenses. What Triggers photochromic Glasses? The molecules that make up a photochromic lens (Photochromic lenses) are triggered when they are exposed to UV light and this is what causes them to darken. The amount of UV light needed to trigger this change depends on the type of Lens that is being used however they all generally start to darken when exposed to sunlight (even when the sun is stuck behind a stubborn cloud) How do I know If My Glasses are Photochromic? You’ve got new glasses but you aren't sure if they are photochromic glasses. There are a few tricks to confirm if your glasses are photochromic or not. All you need to do is set up different lighting conditions that can trigger photochemical reactions seen in photochromic lenses. Here are a few things to do to activate a photochromic lens. If your glasses darken under these conditions, you are likely to have photochromic glasses in your hands. Go Outdoor in the Open The easiest way to activate a photochromic glass is to go outside on a sunny day because photochromic lenses are activated by UV lights and they are abundant in sunlight. A photochromic lens will start to darken the second they are exposed to the sun on a bright day. However, note that this test may be negative if done in a car. photochromic lenses don't work well in cars generally because the windshield of the car blocks a significant amount of UV rays from the sun. Use a UV Flashlight Perhaps it is not so sunny where you stay and you can't wait for the sun to come out to confirm the type of lens you use. You can simply get a UV flashlight to activate your photochromic lens. You can easily get a UV flashlight from your local hardware store or an online store that delivers fast. If your lenses darken when you expose them to the beam from your flashlight, you definitely own a pair of photochromic glasses. Use a UV lamp A good alternative if you can’t get a UV flashlight is to use a UV lamp. And, no, UV lamps don't look anything like UV flashlights. UV lamps are often used in tanning beds and can emit enough UV light to activate your lenses and confirm if they are photochromic. However, be careful not to expose yourself to too much UV rays as they can be harmful to your skin. Don't Conclude too quickly. Don't be quick to judge if your lenses don't darken quickly when exposed to UV lights. A good-quality photochromic lens can darken in a few seconds. However, most photochromic lenses take about 30-60 seconds to darken when exposed to ultraviolet light. They can even take up to a few minutes depending on the brand and the photochromic molecules in your photochromic lenses. Similarly, when you go back indoors, the lenses will gradually lighten up. If any of this doesn't work, no need to fret you can order a pair of Photochromic glasses from Maat Optical. What Are Some Common Misconceptions About photochromic Lenses? There are a few common misconceptions about photochromic lenses that we'd like to clear up: Do Photochromic lenses work inside the car? Yes, but much of the ultraviolet radiation that activates the photosensitive lenses is absorbed by the windshield, and they are not as dark inside the car as they would be outside. However, some newer cars have windshields that allow more UV light to pass through, which can activate the lenses. Although Photochromic lenses provide some degree of protection from in-car glare, some users may prefer a pair of sunglasses for long-term driving. Do Photochromic lenses replace conventional sunglasses? For general use - whether indoors, outdoors, day or night - Photochromic lenses offer excellent visual performance and glare protection. However, in intense sunlight, in high-temperature environments, inside automobiles with windshields that block most ultraviolet radiation, or in environments with intense reflections from surfaces such as water and snow, a unique pair of glasses made under prescription with a fixed shade will offer better protection against glare and more visual comfort. They don't work in cold temperatures Some people believe that photochromic lenses won't darken in cold temperatures. While it's true that extreme cold can affect the lenses' performance, they should still darken in most normal temperature conditions. Photochromic Lenses are always Dark Photochromic lenses are not always dark as some people believe. Photochromic lenses are designed to adjust to changing light conditions, so they won't always get very dark. The amount of darkening depends on the amount of UV light present. If you're in an area with low UV light, your lenses won't get as dark as they would in bright sunlight. Final Words Now you know how to differentiate a photochromic lens from a non-photochromic lens. If you found out your lenses are photochromic, great, now you have a stylish and practical two-in-one solution for people who don't want to carry around multiple pairs of glasses. However, if you found out your glasses are clear glasses and you want photochromic glasses, Maat Optical has been dedicated to the art of producing photochromic lenses for more than 20 years and they are ready to satisfy all your photochromic lens needs.
The transitioning that a Photochromic lens undergoes when exposed to sunlight (or Ultraviolet Light in general) can seem like magic. One second you are indoors with your clear glasses, the next moment you are outside and have sunglasses-like shades on your face without changing frames. It is a quite fascinating phenomenon and it has left many wondering the exact magic trick behind this rapid change in color density. This guide carefully explains the science behind the change in color a photochromic lens undergoes when exposed to sunlight as well as their many benefits. What Are Photochromic Lenses? A Photochromic lens is a lens that stays clear indoors away from light and darkens upon exposure to ultraviolet light from the sun. They serve a dual function of both glasses and sunglasses. The first photochromic lenses were made from glass and were patented in the 1960s. Over time, plastic lenses were developed in the 80’s and 90’s and are now the go-to and popular choice among modern users. How Do Photochromic Lenses Work? Photochromic lenses contain light-sensitive molecules that shift their structures when they are exposed to UV rays from the sun. This change in structure allows them to be able to absorb more light and concurrently give the lenses a darkened appearance. Once the light source is taken away, the structures shift back to their initial conformation, and the process is reversed thereby giving the lens a clear appearance again. These molecules are sensitive to the presence of UV light and the amount of UV rays passing through them. This means that their structural change is faster in the presence of more UV light and this change is slow when they are exposed to a minimal quantity of ultraviolet rays. This explains why your photochromic lens may not darken as much when you are in a shade as opposed to being directly hit by the sun. However, this doesn't mean you need to stand directly in the sun to receive daily doses of UV rays. Ultraviolet light penetrates the clouds and your photochromic lenses will darken just fine under overcast skies. Do you want finer details on the working mechanism of photochromic lenses? The exact working mechanism is dependent on the material used to make the lens. This is explained below. How Do Plastic Photochromic Lenses Work? Plastic photochromic lenses are made from carbon-based compounds and this is what is reactive to light and changes structures in the presence of UV light. They are also called photochromic dyes. Their actual chemical names are quite long like pyridobenzoxazines and indenonaphthopyrans - you don't need to bother with them. However, it is important to know that these organic chemical compounds react faster and change color quickly than molecules used in glass photochromic lenses. Once exposed to light, the chemical bond in these dyes break causing a structural transformation that allows them to absorb more visible light. The more the light absorbed, the darker the lens becomes; and there is the magic trick. Once UV light penetration reduces, these dyes go back to their initial structure and the lenses become clear as day all over again. Plastic photochromic lenses are more common than their glass counterparts and research is still ongoing on how to make these plastic lenses even better. How Do Glass Photochromic Lenses Work? Glass photochromic lenses have several minute amounts of silver halide scattered inside them. The popular halide used is Silver Chloride. Once these chemical compounds are exposed to ultraviolet rays, the silver ion compound gains an electron to become an ionic (or elemental silver). These released silver absorb visible light. Thus, the more silver released, the darker the lens becomes as it absorbs more visible light. Many photographic films employ this same silver halide chemical mechanism. Exposure to light causes the images on them to darken. However, photochromic lenses are different in that they revert back to their original clear appearance when the ultraviolet light source is taken away. Once UV rays are withdrawn, a second compound in the glass (usually copper chloride) accepts the electron back from the silver metal. This causes the reaction to be reversed and the lens becomes clear once again. While photochromic lenses made from glass are not common anymore, this first set of technology paved the way for the current trend employed in light-responsive glasses. Parameters Used In Photochromic Lenses And What They Mean There are various parameters used in the photochromic lens industry. It is important to understand these parameters as they allow you to pick the right lens for use. The various parameters include: 1. Material: The material of a photochromic lens can vary depending on the manufacturer. The glass and plastic materials have been covered in previous sections. However, there is also the polycarbonate material which is very effective and widely used. Examples of materials you will find when shopping for a photochromic lens include: CR-39 (Columbia Resin 39), photochromic oligomer, PMMA (Polymethyl methacrylate), MR-8, MR-7, and PC. Usually, polycarbonate is preferred because of its strength and resistance to impact. However, glass and plastic have their advantages over polycarbonate. For example, MR-7 is loved for its thinness and lightweightness. 2. UV Cut-off: This is the wavelength below which the substance or chemical used in the photochromic lens can absorb all the UV rays. Therefore, the higher the UV cut off the better it is at blocking UV rays. Most photochromic lenses at Maat Optical have a minimum UV cut-off of 360, while some can go as high as 410 which is very good. 3. Option Color: Photochromic lenses come in different colors which can include blue, yellow, clear, brown, gray and so on. While one color might have an advantage over the other, they are mostly selected based on personal preference. 4. Abbe Value: The abbe value is the measure of the extent to which light is separated or dispersed when it passes through the lens. The higher the abbe value, the better. Plastic materials have been found to have the best abbe value while polycarbonate materials have been found to have the worst. An abbe value greater than 50 is very good. Other parameters of a photochromic lens include power range, coating and specific gravity. How Quickly Do Photochromic Lenses Work? Photochromic lenses darken in 30–60 seconds on average when exposed to ultraviolet light. To clear, they take a bit longer: 2–3 minutes is normal. Scientists are still working with photochromic dyes to quicken the reactivity of the lenses. In the future, we could see faster and faster activation and clearing times. How Does Temperature Affect Photochromic Lenses? The rate at which photochromic lenses darken or clear up is impacted by temperature. When it’s colder, the lenses are apt to darken a bit more fully but take a longer time to clear up. When it’s warmer, they may not darken quite as much but will clear up more quickly, as the molecules within them are more reactive. Do Photochromic Lenses Wear Out? The more photochromic lenses are exposed to sunlight the less they become reactive to light and the longer they take to darken when exposed to sunlight. They may also develop a yellowish tint with use over time. Eventually, your photochromic lenses will become less reactive to ultraviolet light and will take longer to shift between their two states. They may also take on a yellowish tint that signals their age. Most photochromic lenses will perform well for three years or more, however, so they’re still a long-term investment. Conclusion Photochromic lenses are of great value to everyone as they protect your eye from harmful UV rays. Photochromic lenses are able to do this due to the presence of some specific chemicals. Photochromic lenses don’t last a lifetime, however, you can get a very durable and authentic photochromic lens from Maat Optical.
Sometimes, we get tired of changing and swapping our glasses every time we enter or leave a place. However, thanks to photochromic lenses, it is now possible to wear just one pair of glasses all the time. These lenses have the ability to change their color and opacity intelligently with surround lighting, protecting your eyes without the need to change to another pair of glasses. Maat Optical explores what you need to know about these lenses, their benefits, how they work, and the qualities of the different colors that different types of photochromic lenses have. What Are Photochromic Lenses? A photochromic lens is a corrective lens that has the capacity to tint depending on the amount of ultraviolet (UV) to which it is subjected. They look just like regular clear lenses when worn indoors but they automatically darken (up to a sunglasses feel) when you move to a brighter environment. This is because Ultraviolet (UV) rays from the sun affect the molecules in these lenses causing them to change color. Thus, these lenses darken even on cloudy days, since although the sun is not really seen, UV rays can still penetrate the clouds. Photochromic lenses always give you the best possible vision in all types of lighting. They are also called Transition lenses, adaptive lenses, self-tinting lenses, or variable tint lenses. Their special characteristics make them ideal for people with sensitive eyes. Photochromic glasses should not be confused with polarized sunglasses. The latter have a set tint that protects your vision from glare, but they do not change color; They do not adapt to light in the same way that photochromics lenses do. What Are The Benefits Of Using A Photochromic Lens? Photochromic lenses are of very great importance to every individual irrespective of where you stay. Here are a few benefits of having a photochromic lens: ●They help reduce eye strain and the risk of developing cataracts, as they block up to of UV rays. ●Photochromic lenses prevent glare and reduce eye fatigue for more comfortable vision. ●With photochromic lenses, it will not be necessary to change glasses every time you enter or leave closed spaces. The lenses adapt to the environment depending on the amount of natural light they receive. ● They save costs since you will only have to invest in a single pair of glasses as opposed to two. ● They are available in many shapes, colors, and brands to cater to different lifestyles. ● They provide continuous protection against UV rays regardless of whether you are exposed directly to the sun or remain indoors. Why Our Eyes Shouldn’t Be Exposed to Ultraviolet Rays? Ultraviolet rays are dangerous to the eyes. They attack our eyes directly, by diffusion, or by reflection. While the direct entry of UV rays into the eyes over time is not healthy, reflected UV rays are just as harmful. Our eyes can also be affected by rays reflected from water, sand, or snow. Water reflects about 10% of UV rays, sand at 20%, and snow at 85%. To ensure that your eyes are protected against aggressive rays, it is strongly recommended to wear glasses with photochromic lenses. Research has reported that light pollution caused by the sun's rays (and blue light) increases age-related macular degeneration or AMD. AMD is characterized by the aging of the central area of the retina or macula. Research shows that nearly 20 million adults in the U.S. have some form of age-related macular degeneration and this emphasizes the increasing need to protect our eyes from constant exposure to UV rays. How Do Photochromic Lenses Work? The lenses in photochromic glasses are often made from carbon or SilverChloride and these molecules react to UV rays; They change shape and absorb light, resulting in color change. The more UV rays absorbed by these lenses, the darker the lenses will become. They can easily adapt from light tones to darker tones. Thus, they help protect your eyes from dangerous or harmful levels of Ultraviolet rays. To know more about how photochromic lenses work, read our article; How do photochromic lenses work? How Dark Do Photochromic Lenses Get? The extent of dark shade achieved by photochromic glasses depends on the amount of solar radiation that falls directly on the lenses. However, these levels of darkness are predefined and can’t be changed. Broadly, photochromic lenses can go up to 75% dark. In rooms or indoor spaces illuminated by natural light, photochromic lenses may only darken slightly as UV rays continue to penetrate. However, the darkest shade is seen when they are fully exposed outdoors, where the lenses will rapidly change from clear to intense dark shade. How Long Does It Take For Photochromic Lenses To Change From Light Shade To Dark Shade? Thanks to the evolution of technology, opticians are now able to manufacture photochromic lenses that change color quickly in just a few seconds. The dark color change is often fast but can take up to 30 seconds depending on the manufacturer. Returning to its light tone may take up to 5 minutes. Upon detecting the presence of ultraviolet rays, the photochromic molecules quickly change their structure simultaneously and become dark. Once the presence of natural light decreases, the lenses regain their transparency and turn to a clear shade. Are Photochromic Lens Different From Transition Lens? Most people use the term photochromic lens and transition lenses interchangeably. However, there are slight differences between a photochromic lens and a transition lens. Transition lenses are known to be a specific type of photochromic lens and this is why most people don’t see the difference. Here are a few differences between a photochromic and a transition lens: ●Transition lenses have a lesser transition time when compared to a photochromic lens. ●Transition lenses can get darker than a photochromic lens. ●Most transition lenses would cost more than a regular photochromic lens. However, this still depends on the design and additional coating. ●Transition lenses are only available in specific designs and are not as flexible and largely produced like a photochromic lens. Photochromic Lens Colors And Their Properties. The lenses of photochromic glasses can come in different shades and colors. Some color types are recommended for specific use depending on your daily activities and lifestyle. Below are the most common color shades and their individual properties. 1. Brown ●It is a pleasant color that does not excessively alter the perception of colors. ●Reduces visual fatigue. ●It is recommended for outdoor sports. ●Suitable for people who have undergone cataract surgery. 2. Grey ●It is the most neutral color and the shade that least alters the perception of colors. ●Suitable for constant use. ●They are the preferred shade if you want to drive your car with glasses on. 3. Verde (grass green) ●This color alters colors more than gray and brown lenses although this is not really noticeable and it is easy to adapt to this change. ●Recommended for water and winter sports ●Suitable for people with long-sightedness. 4. Yellow ●They provide great luminosity and greater contrast than other lenses. ●Highly recommended specifically in low light conditions, such as driving at dawn, dusk, or in fog. ●They may be suitable for some retinal diseases. Who Can Use a Photochromic Lense? Photochromic lenses are for all types of people, of any age and there are no specific contraindications to its use. They are ideal for people who need to use glasses all the time. They are also compatible with most frames and prescriptions. Your optometrist will recommend the ideal lenses for your visual needs. Photochromic lenses are especially great for people who travel a lot especially to places with a hot temperature. Also, it is great for people who play outdoor games like golf or skiing. This doesn’t mean it can’t be used for everyday use or other forms of activities. The Downside to using Photochromic Glasses Although wearing photochromic lens glasses is recommended for people who wear glasses at all times, it still has some limitations and disadvantages. First off, photochromic lenses are ineffective when worn behind the wheel. This is because modern car windshields are designed to block most oncoming Ultraviolet rays and thus photochromic lenses won't darken. In addition, these glasses lose their effectiveness when they are exposed to too much heat such as during summer periods. Other downsides of a photochromic lens are: ●They cost more than most regular sunglasses. ●The extent of darkening can’t be controlled and so can get uncomfortable indoors if triggered by some indoor lighting. ●Transition time can be affected by temperature (colder temperature can make it slower). ●Non-polarized photochromic lenses can lead to unwanted glare of sunlight. Choosing Glasses With Photochromic Lenses Purchasing a Photochromic lens doesn't change the usual decision-making process you go through when you want to get your regular pair of glasses. One would usually watch out for frame type, color, and type of material used to make the glasses. Furthermore, it is possible to strengthen your photochromic lenses by treating them with extra characteristics the way you would do your regular pair of glasses to improve visual comfort. Possible treatments to choose from amongst others include; ●Scratch Resistant- to harden the glass and make it more resistant to scratching; ●Slimming - to make your glasses more aesthetically pleasing; ●Anti-reflective - to improve vision and reduce glare from oncoming vehicles when driving; ●Anti-fog - to limit condensation on lenses; ●Anti-dirt - to prevent any deposit of dust and other microorganisms on your lens. Note that you don't need an “anti-blue light” treatment as photochromic lenses also block harmful blue rays emitted by laptop and phone screens. Blue lights from digital screens can cause headaches, insomnia, or even macular degeneration. With photochromic lenses, these can be easily avoided all with one pair of glasses. Do Photochromic Lenses Need Any Special Care? They require the same care as any other type of lens. They can be cleaned with lens cleaner, mild soap, or a microfiber cloth. There are convenient lens-cleaning sprays that can help keep your photochromic lens clean all the time. Also, it is best to keep them in a clean case to prevent exposure to environmental hazards. The benefits of regular maintenance and cleaning of your photochromic lens include: ●Prevent your lens from micro scratches ●Prolong the life-span of your photochromic lens ●Prevent irritation of your eyes when you use them. The One Pair of Glasses You Need Everyone who wears glasses knows that changes in light are sometimes difficult to bear. When the clouds dissipate or when you go from an overcast environment to an outdoor place, do you have to squint your eyes to avoid being dazzled? Do you have to wait a while before you adapt to the change in environment? Do you sometimes forget to take your sunglasses with you when the sun glare is blinding? Almost all of us suffer from these. All you need are photochromic lenses. Frames with photochromic lenses allow you to go from UV protection category 0 or 1 to category 4 in a few seconds without any physical effort. There is therefore no need to carry several pairs of glasses with you. Photochromic glasses are the perfect money saver for you and save you the discomfort of keeping multiple glasses in your bag. Order your photochromic lens today to enjoy freedom and comfort at all times.
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