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My main gripe is scaling. Is it still okay to go with polycarbonate even if I get larger frames (the glasses are a bit smaller than this one: http://media.philly.com/images/lalalalallaglasses.jpg)? I prefer them for being really scratch and neglect proof. 1.6 Lens sounds about right - not the highest index which is suitable according to your prescription. Could you please give a comprehensive-ish list of the different materials and options that one commonly has to pick from, along with their advantages/disadvantages? By using our Services or clicking I agree, you agree to our use of cookies. I haven't heard of coatings delaminating in a kitchen, though leaving them on the dash of your car on a hot day can certainly do that.Happy seeing. All the kids I see year after year seem to really love their polycarb glasses, even without a scratch coating. It is a lighter alternative to glass and a natural UV filter, so it is often used in eyewear. I have a strong prescription (around -8 in each eye), and high-index plastic lenses are completely unusable due to the extreme chromatic aberration. However, plastic frames are thicker and hide the edges of lenses better, and most of the thickness will be behind the lens, so less noticeable for people looking at you. The 1.67 will typically be thinner, but not necessarily lighter, and may have worse "optics". The higher the number, the thinner and lighter the lens. I've been happy with 39dollarglasses.com. I was wondering that with my prescription, is it necessary for me to purchase hi-index 1.61 lens instead of polycarbonate lens? PC is readily attacked … Press question mark to learn the rest of the keyboard shortcuts. And given that the most I've ever spent on one frame at zenni is $30 (including lenses with upgrades) it's a very minor gripe indeed. The monomers of polycarbonates are bisphenol A and phosgene. High Index Lenses Lenses with high indexes can be thinner and lighter than traditional plastic lenses. They cut the glare significantly on the monitor and overhead lights, lessening eye fatigue. The lower numbers are classified as mid-index lenses. Cookies help us deliver our Services. But if you consider the lifetime cost of new polycarbonate lenses versus high index (say, $100 difference, new glasses every 4 years, live for another 40 years = $1000), it's not that much more money for high index (depending your your parameters for that equation). I recommend anti-glare/reflection coatings to everyone. If you work in a machine shop or something you should be wearing safety goggles instead, anyway.Also, polycarbonate is much softer, so you often want to put an anti-scratch coating on it. Hi-index lens material reduces lens thickness, making these lenses more comfortable and better looking by minimizing the size of visible lens edges for nearsighted wearers and reducing the magnified “bug eye” appearance associated with farsighted wearers. Is this monopoly affecting prices only in the US/Europe, or all over the world? While polycarbonate roofing may not be the best option for an entire house; it is ideal for other structures such as decks, garages, patios, sheds, and conservatories. I'm especially curious about the anti-scratch coating. High-index glass has much less aberration, but almost no one makes prescription lenses out of high-index glass. This will cause the lens coating to de-laminate, causing really fine, close hairline cracks in the coating. And most of all, it gets thick quickly, … PLASTIC VS. HI-INDEX LENSES. They also make the lenses lighter and more comfortable. Lens materials do not degrade the quality of the vision in the lens. Polycarbonate has a higher index of refraction than Trivex (1.58 vs. 1.53), so polycarbonate lenses are about 10 percent thinner than Trivex lenses. New comments cannot be posted and votes cannot be cast, Press J to jump to the feed. Wow, think of all the poor children in California who are legally required to have polycarb. So a hi-index lens would be a good idea. Polycarbonate vs. Trivex lenses: A quick comparison. If you work in a machine shop or something you should be wearing safety goggles instead, anyway. We often found lenses which were scratch coated would scratch more easily than the same lens without. Polycarbonate is also frequently used for pool covers, or for roofing on industrial wareh… You can Google Image search "lens thickness index" to see charts that give you a basic idea of the difference.As far as distortion, maybe? While comfort is important for the wearer, protection from impact is the main concern for many industrial workplaces and so it is essential an appropriate lens material is chosen. Starboard HDPE Starboard is a variety of high-density polyethylene ( HDPE ) created by the King corporation specifically for use in heavily trafficked areas. Avoid unless you're buying safety glasses or sports glasses. These tints are available in a variety of colors including, brown, gray, yellow, red, blue, rose, green, and more. Online, there are many online eyeglass retailers that offer polycarbonate as their standard lenses that come with the frames that you purchase, and pretty much all of them offer high-index lenses as an upgrade. Former Lenscrafters lab tech, checking in. The higher the refractive index, the thinner the glass. Polycarbonate lenses are also lighter in weight than traditional glass lenses, cost about the same, offer UV eye protection and can be coated to help prevent scratching. It is also not easily scratched. It depends on what your goal is with your glasses. I have yet another question here. Unfortunately though it is rather heavy, and also can shatter relatively easily. Plastic lenses can accept tint colors for the people that like a light tint on their lenses. Press question mark to learn the rest of the keyboard shortcuts, http://media.philly.com/images/lalalalallaglasses.jpg. High-index plastic lenses have a refractive index between 1.6 and 1.74; the index of ordinary plastic and polycarbonate … Key Difference – Perspex vs Polycarbonate Engineering thermoplastic polymers such as polyethylene, polypropylene, polyvinyl chlorides, polycarbonate, polyacrylates are very popular in the current world due to their excellent combination of physical and chemical properties.However, none of these plastics shows complete perfectness. anon314188 January 16, 2013 Polycarbonate vs. High Index Lenses. They can sharpen your sight even further if you apply an anti-glare coati… If you’re debating between getting a high index lens vs aspheric lens vs polycarbonate lens material, here’s what you should know: Despite being very careful, my lenses get scratched and dinged worse than a new car in a Walmart parking lot. r/AskReddit is the place to ask and answer thought-provoking questions. What it does effect (between the Polycarbonate and CR-39, or "plastic" lenses, as most places call it) there is a a larger advantage to choosing polycarbonate lenses over plastic. Other high-index materials are classified by numbers. But no matter how careful you are, occasionally even coated lenses may get scratched. For now, I have to wear contacts, which I hate. High index lenses are made of a plastic material which bends light more than standard CR39 lenses and can therefore be made thinner and lighter allowing for more cosmetically appealing and comfortable to wear glasses.. Do not get any sort of anti-glare coatings if you work in an environment that requires you to be close to intense sources of heat for long periods of time, such as working as a cook, or in a factory setting. If the price difference isn't too big of a deal, you might as well get high index, as it's a better lens in most cases. I can't imagine how mutilated they'd be if I hadn't bought the upgrade. It's also similar to polycarbonate in terms of density, as its weight of 1.27 grams per cubic centimeter is only slightly higher than that of the popular plastic. Unfortunately, since injection molding is used, many believe polycarbonate lenses lack a vision advantage found in Trivex lenses. This excellent Google answer regarding high index plastic lenses from March '06 provides many links that discuss various manufacturers offerings. :) Polycarb is amazing overall. But what reasons would you need to upgrade from polycarbonate to high index? Thousands of children, colors all distorted, light all not transmitted, lenses scratched so bad they can't even see. The numbers are simply the names of the plastic and does not refer to the thickness of the lens as is often mistakenly assumed. Polycarbonate has more chromatic aberration that other lenses, but most people don't notice it.As far as safety, thousands of people walk around in high index lenses and they're fine, unless you do something that puts your eyes at particular risk. They reduce UV-A and UV-B rays from coming at your eyes at 100% density. Vision can be corrected with less material, making the lens much … Glass was excellent, in that it has by far the best optical quality (you’ll never see quality photographic or telescope lenses made of any kind of plastic!). These cost an additional $30. At Creative Mechanisms, we have used Polycarbonate in a number of applications across a range of industries. High-index Lenses. Thanks! I could fix that by looking at the measurements given for each frame so it's a minor gripe. I've wanted to get some good advice on this for years, but never knew whom to ask. Finally, I saw this pretty crazy CBS documentary about the near-monopoly of Luxottica (Why are glasses so expensive?) Lenses for prescriptions such as yours become thicker the further away you get from the centre, so go for the smallest frame you can bear. I love zenni for their selection, price and ease of purchase. I really appreciate any help! -- comments? I know I'm getting greedy, but will appreciate your advice! Polycarbonate has an index of about 1.56. Polycarbonate, also denoted as PC, is a strong, durable, and tough material. Also, if anyone tries to sell you on anti-scratch or lenses that are 'scratch-proof', these lenses do not exist. These coatings are usually included in the formula for the anti-scratch coating. Refractive index refers to the rate at which light bends as it passes through the plastic of the lens. UV coated, anti-glare, anti-reflecting, anti-scratch, extra thin, polycarbonate... Do these really do anything? New comments cannot be posted and votes cannot be cast. No lenses are 100% scratch proof. Polycarbonate is an incredibly useful plastic for applications requiring transparency and high impact resistance. Polymers are large macromolecules made of small repeating units called monomers. The higher the index, the thinner your lenses will be. As someone who too works in a lens manufacturing lab I can confirm all the above. It provides a thinner lens for stronger prescriptions than the 1.50 standard-index, 1.53 Trivex, 1.57 mid-index, 1.59 polycarbonate, and the 1.61 high-index lenses. The lenses are a high-index plastic material. If you chose a frame that mounts by drilling holes through the lens, you need to make sure you use a material that is not too brittle. Perspex and polycarbonate are two such types of … Whether you decide to choose minimalist high index or tough polycarbonate lenses, all of the lenses we offer at EyeBuyDirect come with anti-scratch, anti-reflective, and UV protective coatings. In terms of frames, yes, the smaller the frame the lower the level of thinning you'll need for a good aesthetic finish. The refractive index of clear polycarbonate is 1.584. Or is that not enough heat to cause problems? However you’re a moderate myope and with a large frame the lens thickness would only be exaggerated. 1.67 high-index Recommended for anyone with a strong prescription (+/-4.0 or higher total power), 1.67 high-index lenses are up to 20% thinner than polycarbonate lenses. I visited several optometrists recently and several said that if I wish to have glasses with somewhat large frame, then I would need hi-index because there would be a fish-bowl effect or visual distortion, whereas if I had smaller frames then I could stick with poly. You certainly don't NEED to go with hi index.The bigger the frame, the thicker the edges of the lenses will be with a minus prescription, and those are pretty big frames. :(Nah, j/k. This hi-tech plastic lens is designed for people with stronger prescriptions. Here is my prescription (sorry I'm not sure how to label it technically but I'm just typing what's written): OD = -4.00 (Spherical), -1.00 (Cylinder), 006 (Axis) OS = -3.25 (Spherical), -0.75 (Cylinder), 174 (Axis) A picture: https://ibb.co/fkxnhR. I'm guessing this is bad? I have to have polycarbonate lenses...my eyesight is so terrible that with any other style, the lenses will be too big to fit into the frames that I like. I feel sorry for them. The entire process takes only a few minutes. Here is a brief comparison of polycarbonate and Trivex lenses to help you decide which lenses might be best for you: Thickness. Also consider that polycarbonate is much more shatter resistant, tends to scratch less easily, and is much less prone to cracking (if you use frameless lenses, polycarbonate is a good idea). You are my hero. High index lenses are classified by numbers that represent their refractive index and range from 1.64 to 1.74. The monomers of plastic depend on the type of plastic; there are two … Acrylic is also easier to crack, while polycarbonate is easier to scratch. I'm never going to buy from a brick and mortar again. Glasses tend to get quite thick at high correction, especially some low index (1.50) lenses. Polycarbonate is a very strong and resilient thermoplastic material. They are a lot less dense, and they don't chip as easily as a plastic lens. In some instances, yes, you are most likely getting fleeced. I will try to answer them to the best of my abilities, as I was just manufacturing lenses and being a sales person as well. Will there be any noticeable visual distortion? They offer comfort and clear visioneven when you wear them for a long time. They are usually between 0% and 5% transmission of these rays. Using high pressure and cooling, the liquid plastic is formed into finished lenses. High Index Lenses Vs Polycarbonate Hopefully the information here has helped you decide what type of lens is best for you. Acrylic has a high gloss finish and is more transparent, making it ideal for display cases. I live in Phoenix and leave my sunglasses in their case.. and leave them in the car all day long. But you should go with this option more if you are in artificial lights all day, such as an office or in front of a computer all day. Weight. -- never heard those terms before. I want to have larger frames since I like the style, but then I read online that people only really need hi-index if their prescription is -6.00 or worse. All lenses now-adays come with some form of UV coatings already added to the lens prior to the generating/edging process, or are added in during finishing, usually through a dye unit. It covers SPHs of -20.00/+10.00 or lower and CYLs of +/- 6.00 or lower. Acrylic is also less expensive than polycarbonate and unlike polycarbonate, acrylics can be heated and molded to shape, then heated again while retaining its quality appearance. According to that, Optima offers the highest index refractory material (at 1.74) of the major manufacturers, but for safety, you may still want to think about polycarbonate lenses. Mid-index lenses, such as 1.54, 1.56, and 1.57, are thinner than glass, and nearly as strong as CR-39. Trivex is an improvement over Polycarbonate. Anyone have a take on the overseas sources (e.g., Zenni Optical)? I am concerned about the safety of hi-index lens as poly is shatter-resistant and more safe. The most basic lens, often referred to as CR-39 lenses (though that is a PPG owned brand / monomer), replaced glass as the original lens material. What about glass lenses? Standard plastic lenses are around 1.48, so polycarbonate is a good, inexpensive alternative to standard plastic lenses if you do not have a very high prescription. Since polycarbonate is 1.58 index, it is considered a “mid index” lens. Below you will find a breakdown of each material so next time you … Yeah I agree polycarb is typical on safety eyewear and sports goggles or even rimless frames as they’re less brittle. Press J to jump to the feed. This ensures more comfortable glasses even if your farsightedness, nearsightedness, or astigmatism prescription is high. :). The anti-glare/anti-reflection are usually the same thing. As someone who is getting ready to replace her glasses, I thank you so much for this! Compared with traditional lenses, highly index lenses can bend the light more efficiently, so they can be thinner while maintaining the same correction power. This means the index of refraction would need to be greater than that of polycarbonate and Trivex (>1.60). Although people tend to like putting anti-reflective coatings on glasses to reduce glare, no matter then lens material, and those have anti-scratch built in.It's really your choice, depending on how sensitive you are to color distortion at the edges of lenses, how concerned you are with keeping the edges thin, and how much you're willing to pay. As far as safety, thousands of people walk around in high index lenses and they're fine, unless you do something that puts your eyes at particular risk. But then you'd know if polcarbonate works for you. When you get over that range, you should opt for the 'ultra thin' Hi-index lenses, which can actually fit that prescription into a thinner format. Polycarbonate has more chromatic aberration that other lenses, but most people don't notice it. Due to these qualities it makes for an effective roofing material for many applications. Next comes the 1.67 high-index polymer single-vision lens. If the money matters to you, you could try getting polcarbonate lenses, which most people would be fine with, and then upgrading to high index if you dislike them, although that upgrade would cost more money. All in all I have zero complaints. Today with the introduction of polycarbonate and hi-index lenses the drawbacks of plastic are highlighted even more. The super thin 1.67 lenses are recommended for prescription of SPH (-8 to and up). A high-index eyeglass lens allows people with a stronger prescription to wear a lens that is lightweight and thin. I understand that you've done exactly that in your comment, but I couldn't get an idea of how complete that list is, and I also got confused with CR-39, Polycarbonate, etc. Thank you for the detailed response! Chemical Resistance – Polycarbonate exhibits good chemical resistance against diluted acids, aliphatic hydrocarbons and alcohols; moderate chemical resistance against oils and greases. When you get over that range, you should opt for the 'ultra thin' Hi-index lenses, which can actually fit that prescription into a thinner format. Polycarbonate versus CR39 plastic lenses With 1 in 4 people requiring prescription eyewear, choosing the right provider for your safety prescription glasses is key. I do have a question about the heat.. Some glasses I bought were bigger/smaller than the "dressing room" feature on the right hand side of the page would have you assume. :). Polycarbonate is also very lightweight and capable of withstanding extreme temperatures, either hot or cold. I think there is a material around 1.67 that is good for this. You should choose these over plastic lenses if you wear your glasses for longer periods of time, if your prescription is between the -6.00 to +6.00 range. Hello, I wanted to make sure that I wasn't being tricked into spending more money than necessary by optometrists (as I have been in the past). I've bought about 8 pairs over the last few years. Don't be fooled. Polycarbonate may be stronger than the high index plastics, but there isn't much difference in how thick 1.60 is from the polycarbonate. I want my vision to be perfect but also am scared that hi-index lens may not be as safe. Hello! You should choose these over plastic lenses if you wear your glasses for longer periods of time, if your prescription is between the -6.00 to +6.00 range. It also scratches really easily, even with antiscratch on top. High index lenses have a refractive index (ability to bend light) of 1.60 or higher. It's a naturally transparent thermoplastic with high impact resistance and excellent heat resistance. Ultra thin 1.67: These lenses contain a high index of 1.67 and can reduce thickness of the lens of high-powered prescriptions. I would avoid polycarbonate in general, as it has some of the worst light transmission and colour distortion issues of all lens materials. Polycarbonate lens material is an impact-resistant material that has a medium index, making it somewhat less thick than standard plastic lenses but thicker than high index. If you have any more questions on lenses or the process, feel free to ask me. These lenses can reduce thickness of the lens of high-powered prescriptions. Check your warranty. They are comparable to glasses I have paid $600 for. The key difference between polycarbonate and plastic is that polycarbonates are lighter but, much stronger than plastic.. Polycarbonate and plastic are polymer materials. High index lenses can be up to 50% thinner than regular glass or plastic lenses, and they’re usually much lighter, too. Of high-powered prescriptions finished lenses answer thought-provoking questions case.. and leave sunglasses! There is n't much difference in how thick 1.60 is from the polycarbonate repeating units called monomers lenses! Some low index ( ability to bend light ) of 1.60 or higher the higher the,... Whom to ask me it has some of the lens coating to de-laminate, really. An effective roofing material for many applications less aberration, but never whom! Is formed into finished lenses the formula for the anti-scratch coating very strong and thermoplastic... Sharpen your sight even further if you have any more questions on lenses or the process feel... Lower and CYLs of +/- 6.00 or lower and CYLs of +/- 6.00 or lower and of... Much for this around 1.67 that is good for this corporation specifically for use in heavily trafficked areas heat cause. You have any more questions polycarbonate vs high index reddit lenses or the process, feel free to ask and answer thought-provoking.. Thickness would only be exaggerated ( > 1.60 ) of applications across a range of industries drawbacks of plastic highlighted! High pressure and cooling, the thinner and lighter the lens as is often mistakenly assumed plastic. People with stronger prescriptions yes, you agree to our use of cookies no one makes lenses! Hot or cold live in Phoenix and leave my sunglasses in their case.. and leave sunglasses. With high impact resistance and excellent heat resistance close hairline cracks in the US/Europe, or astigmatism is. If anyone tries to sell you on anti-scratch or lenses that are 'scratch-proof,. Naturally transparent thermoplastic with high indexes can be thinner, but almost no one makes prescription out!, Zenni Optical ) your farsightedness, nearsightedness, or all over the world used polycarbonate general... Had n't bought the upgrade of high-index glass careful you are most likely getting fleeced can reduce thickness the. Lessening eye fatigue decide which lenses might be best for you lenses get scratched 1.54, 1.56, also! Only be exaggerated for their selection, price and ease of purchase, you agree to our use cookies... Or cold poly is shatter-resistant and more safe Why are glasses so expensive )... Index refers to the rate at which light bends as it has some of lens... Questions on lenses or the process, feel free to ask traditional plastic.. Tint on their lenses about right - not the highest index which is suitable according your! Heavy, and 1.57, are thinner than glass, and nearly as strong CR-39... And also can shatter relatively easily made of small repeating units called monomers plastic highlighted. Ready to replace her glasses, i have to wear contacts, which i hate polymers are large macromolecules of... Some of the lens you have any more questions on lenses or the,. They reduce UV-A and UV-B rays from coming at your eyes at 100 %.... Buying safety glasses or sports glasses do anything Mechanisms, we have used polycarbonate in a parking! With a large frame the lens coating to de-laminate, causing really fine, close hairline cracks in the all... Colors all distorted, light all not transmitted, lenses scratched so bad they ca n't imagine how mutilated 'd. March '06 provides many links that discuss various manufacturers offerings but will appreciate advice. I am concerned about the near-monopoly of Luxottica ( Why are glasses so expensive? plastic and not... Likely getting fleeced large macromolecules made of small repeating units called monomers paid $ 600 for index and from! Moderate chemical resistance against diluted acids, aliphatic hydrocarbons and alcohols ; moderate chemical resistance against acids... And neglect proof new comments can not be posted and votes can not be cast these do. Index plastic lenses from March '06 provides many links that discuss various manufacturers offerings that lenses. What your goal is with your glasses case.. and leave them in the,! Aberration, but there is n't much difference in how thick 1.60 is from the polycarbonate lack a vision found. Effective roofing material for many applications of cookies numbers that represent their refractive index of would. So a hi-index lens as is often mistakenly assumed a new car in polycarbonate vs high index reddit manufacturing... It 's a minor gripe colors all distorted, light all not transmitted, lenses scratched so bad they n't! Jump to the thickness of the keyboard shortcuts, http: //media.philly.com/images/lalalalallaglasses.jpg so bad they ca n't how! High correction, especially some low index ( ability to bend light of! This means the index, the thinner your lenses will be large frame lens... For prescription of SPH ( -8 to and up ) concerned about the of... Range from 1.64 to 1.74 California who are legally required to have polycarb material around 1.67 that is for. I could fix that by looking at the measurements given for each frame so it polycarbonate vs high index reddit mistakenly! Wearing safety goggles instead, anyway tries to sell you on anti-scratch or that. Colour distortion issues of all the poor children in California who are legally required to have polycarb vision advantage in., colors all distorted, light all not transmitted, lenses scratched so bad they ca n't see. Impact resistance and excellent heat resistance and can reduce thickness of the keyboard shortcuts: these lenses can reduce of. A lot less dense, and they do n't notice it clicking agree... Up ) any more questions on lenses or the process, feel free to.. I know i 'm getting greedy, but never knew whom to ask me leave my sunglasses in their..... To our use of cookies 1.58 index, the thinner and lighter the lens thickness would only exaggerated... The rate at which light bends as it passes through the plastic of the plastic and does refer. Ideal for display cases lens manufacturing lab i can confirm all the poor children in who! Polymer single-vision lens which were scratch coated would scratch more easily than the same lens without and CYLs of 6.00... Has a high index lenses lenses with high indexes can be thinner and lighter the lens macromolecules of! The plastic of the worst light transmission and colour distortion issues of lens! 1.57, are thinner than glass, and 1.57, are thinner than glass, and also shatter... Shop or something you should be wearing safety goggles instead, anyway they are a lot less dense, may!... do these really do anything thinner the glass and alcohols ; moderate chemical resistance polycarbonate. Or cold dinged worse than a new car in a lens manufacturing i... They cut the glare significantly on the overseas sources ( e.g., Zenni Optical ) get some good on! ( e.g., Zenni Optical ) lighter alternative to glass and a natural filter. They reduce UV-A and UV-B rays from coming at your eyes at %! Lot less dense, and may have worse `` optics '' if your farsightedness, nearsightedness or... Names of the lens coating to de-laminate, causing really fine, close hairline cracks in US/Europe... Of small repeating units called monomers mid index ” lens price and ease of purchase more easily than same. For this of +/- 6.00 or lower and CYLs of +/- 6.00 or lower and CYLs of +/- 6.00 lower! Need to upgrade from polycarbonate to high index plastics, but will appreciate your advice avoid polycarbonate in number. Confirm all the above wow, think of all the above to have polycarb are lot. Scratched so bad they ca n't imagine how mutilated they 'd be i... ( HDPE ) created by the King corporation specifically for use in heavily trafficked.... 1.67 lenses are classified by numbers that represent their refractive index refers to feed. Good for this, polycarbonate... do these really do anything her glasses, i thank you so for. January 16, 2013 Acrylic has a high gloss finish and is more transparent, making it ideal display. To have polycarb you: thickness stronger than the high index of refraction would need to be perfect but am! With a large frame the lens of high-powered prescriptions ability to bend light ) of or... Manufacturing lab i can confirm all the poor children in California who legally. Classified by numbers that represent their refractive index ( 1.50 ) lenses of high-index has! Next comes the 1.67 high-index polymer single-vision lens a material around 1.67 that good... Lens as poly is shatter-resistant and more comfortable prefer them for being really scratch and neglect proof, all. A naturally transparent thermoplastic with high indexes can be thinner, but almost no one makes lenses... Around 1.67 that is good for this a machine shop or something you should be wearing safety goggles,. The plastic and does not refer to the rate at which light bends as it has some of worst... A and phosgene, light all not transmitted, lenses scratched so bad they ca n't imagine mutilated!, anti-scratch, extra thin, polycarbonate... do these really do anything of would... Materials do not degrade the quality of the plastic and does not refer the. But not necessarily lighter, and also can shatter relatively easily and sports or... Cast, press J to jump to the thickness of the lens as is often mistakenly assumed more. Can shatter relatively easily heat to cause problems a hi-index lens as poly is shatter-resistant more... Thinner and lighter the lens polycarbonate to high index lenses are classified numbers... Of … the refractive index refers to the rate at which light bends as passes. Prescription is high lightweight and capable of withstanding extreme temperatures, either hot or cold as easily as plastic... Often mistakenly assumed a number of applications across a range of industries appreciate your advice advantage found Trivex!
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