1.61 vs 1.67 high index

Aug 16, 2019 · The lens index describes the thickness of your lens. At Eyebuydirect, we use the following lens materials for these lens indexes: 1.5 – Plastic; 1.57 – Plastic; 1.59 – Polycarbonate; 1.6 – Plastic; 1.67 – High-index 1.74 – High-index LEARN MORE: Find the recommended lens index for your vision prescription. High-Index Lenses vs ...

1.61 vs 1.67 high index. A 3.67 GPA is equal to an “A” letter grade or being in the 91st or 92nd percentile. GPA stands for “grade point average” and represents the average grade of all the coursework a st...

May 27, 2009 · soft for a drill mount application, so you would have to choose a. polycarbonate or high-index MR-7 or MR-10, 1.60 or 1.67 lenses. Your prescription is very mildly common, so unless you are extremely. concerned with edge thickness or eye minification, then you will be. just fine with nothing higher than 1.61.

EASY View (Instinctive) 1.67 High Index 1 – 3 EASY ... N88 L6738 SYNC SF P EAS V (INST) 167 HC –B- Country of Origin required on Label US FDA disclaimer Required 2. Product Range: Nominal Diameter (mm) Nominal Base Curve (D) Add Power Range (D) Recommended RxStatus code 61 has several different possible meanings depending on jurisdiction. According to The Oregonian newspaper, the police code signal 61 means “subject in custody” in the ...Nov 25, 2020 · A high-index lens may be recommended if your optical prescription is above 2.00 diopters. High-index lenses have a refractive index above 1.50— ranging from 1.53 to 1.74. The image below compares the lens thickness of a regular plastic lens (1.50) to the most commonly prescribed high-index lenses. Note: The higher the refractive index, the ... Feb 5, 2020 · The Blokz by Zenni (starting at $17 plus frame cost) are virtually clear lenses for all-day, everyday use, designed to protect your vision from the blue light emitted from our digital devices that ...We firmly believe the prices of our prescription lenses offer the best value when compared with other online retailers and high street opticians - see for yourself below. Lens Guide ... High Impact (1.56 Index) - Clear Lenses. £70.00. 1.59 D28 Polycarbonate - Clear Lenses. £50.00. 1.60 D28 Flat Top - Clear Lenses. £100.00 + Tints.

Standard index 1.50 (also known as CR-39) Mid-index 1.57. High index. 1.61, 1.67, 1.74. The larger the number, the thinner and lighter the lens, but the higher the cost. 1.61 is up to 20% thinner than standard lens. 1.67 is up to 30% thinner than standard lens. 1.74 is up to 40% thinner than standard lens. Sponsored by FinanceBuzz.Feb 27, 2019 · Trivex lenses about 10 percent lighter than polycarbonate lenses. Optics - central. Trivex lenses have less internal stress and may produce sharper central vision than polycarbonate lenses. Optics - peripheral. Trivex lenses have a higher Abbe value and may produce sharper peripheral vision with less chromatic aberration than polycarbonate lenses. If you were to compare them to a pair of glasses with Trivex lenses of the same prescription, you’ll find that high-index lenses are always thinner and even lighter in higher prescriptions. Weight High index lenses are lighter. Trivex lenses have a lower refractive index of 1.53 as compared to high-index lenses having 1.67 to 1.74. The higher that number, the thinner the lens will be even with the strongest types of prescriptions. And that is the basic difference between 1.67 and 1.74 high index lenses: the latter is simply thinner, and lighter, than the former. Lenses with a refraction index of 1.7 or higher are at least 50 percent thinner than those with a regular index. Feb 22, 2023 · There are a number of different lens index lenses available, with some better suited to certain prescriptions than others. You’ll generally find lens index in the following sizes: 1.5 Standard. 1.56 Mix-Index. 1.57 Thin and Light Index. 1.59 Standard Polycarbonate and High Index. 1.74 High Index Lenses are the thinnest and lightest. Dec 13, 2019 ... Lensa kacamata dengan ukuran power sama, frame yang sama tetapi dipasangi lensa beda index 1.56 vs 1.67. Bagaimana hasilnya?If you’re moderately, or very short-sighted you’ll benefit from thinner lenses as the edge thickness of your lenses will be more visible. Lenses with a refractive index of 1.6 are ideal for prescriptions where the – value of your SPH prescription is between -2.50 and -4.00. Between -4.00 and -6.00 we’d recommend a lens with a refractive ...

Versus the 1.6 lens could be more optically clear, but will undoubtedly be heavier and not impact resistant . The thinnest option available and designed for people that have the best prescriptions, 1.74 high index lenses are the optimal choice should you have a high prescription. 1.67 high index lenses are incredibly thin and light, …ok, without bombarding you with boring science crap, go for the 1.67. A bit more info: the ABBE value difference between a 1.6 and a 1.67 will be negliagble and very nearly no-one would notice the decrease in optical "quality", however the difference in thickness would be noteworthy. A 1.67 will give a flatter front surface, and a …Sep 8, 2020 · For many wearers, this can make the cost of eyewear prohibitive. At JINS, we offer high index lenses of 1.60 to 1.74 free of charge (availability varies). 2. Durability. High index lenses can be more brittle than their traditional counterparts and may also be more prone to scrapes and scratches.As of this review, there are over 800 options for Men, over 1,100 options for Women, just under 100 options for Boys, and over 100 options for Girls. Pricing is all over the place depending on the desirability and material of the frames, but the prices start as low as $6.95 and go as high as $45.95 (that’s the most …

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High index lenses are thinner, lighter, and more appealing than standard lenses, but they come in several different indexes.. If you’re shopping for high index lenses and aren’t sure whether to go for 1.67 or 1.74, we have some information that might help you with your decision.. The main differences between these two lenses are …Blue Light Glasses. Customize your Blokz ® blue light blocking glasses with lenses starting at just $16.95, and experience exceptional eye protection tailored to you. In today's digital world, screens, artificial light, and the sun are unavoidable. But you can defend your eyes against excessive blue light exposure with Blokz ® lenses. The 1.5 vs 1,6 index has no effect on the effectiveness of the blue light-blocking properties of the lenses. The higher index lenses are simply thinner than the standard 1.5, and are advisable if you have a stronger prescription, as the lenses will be lighter, thinner and more aesthetically-pleasing. It would help to know your Rx in order to ... Photochromic 1.67 Transitions VI. In response to customer complaints of slow-transitioning lenses, one of these improvements resulted in the release of Transitions® VI, a photochromic coating that allows up to a 40% faster shift in tint. This upgrade to standard transitional lenses also provides better UV protection …Feb 19, 2021 · Zenni Optical offers three types of high index lenses: 1.61 at an additional cost of $19.95. 1.67 at an additional cost of $34.95. 1.74 at $74.95. So, if you need the high index lenses, you’re ...Welcome to the April 2022 release of Visual Studio Code. There are many updates in this version that we hope you'll like, some of the key highlights include: Explorer file nesting - Nest generated files under source files in the Explorer. Settings editor filters - Filter button brings up searches such as @Modified settings.

Dec 13, 2019 ... Lensa kacamata dengan ukuran power sama, frame yang sama tetapi dipasangi lensa beda index 1.56 vs 1.67. Bagaimana hasilnya? Most polycarbonate lenses have a refractive index of 1.59. This figure means that they can be around 10 percent thinner than other lenses, including glass. By contrast, 1.67 high-index lenses are about 30 percent thinner and lighter, and 1.74 single-vision lenses are 35 percent thinner for the same prescription strength. 1.61 High index lenses are up to 20% thinner than 1.50 Standard index lenses. 1.67 High index lenses are up to 30% thinner than 1.50 Standard index lenses. Stronger prescriptions: They are recommended for individuals with high myopia or hyperopia, providing optimal vision correction while minimizing lens bulkiness. 1.61 vs. 1.67 vs. 1.74 High Index Lenses. 1.61 High Index Lenses. Moderate Prescription Strengths: Ideal for those with mild prescriptions (less than +/- 2.00) Thinner and Lighter: Offers a significant reduction in thickness and weight compared to standard 1.50 CR39 lenses. However, presenting various reasons for why you should and shouldn’t buy 1.67 high index lenses vs standard CR-39 plastic lenses should help those who are undecided: When 1.67 High Index Lenses Make Little Difference. If CR-39 lenses for your prescription level aren’t excessively thick or heavy, then don’t get 1.67 high index lenses. However, presenting various reasons for why you should and shouldn’t buy 1.67 high index lenses vs standard CR-39 plastic lenses should help those who are undecided: When 1.67 High Index Lenses Make Little Difference. If CR-39 lenses for your prescription level aren’t excessively thick or heavy, then don’t get 1.67 high index lenses. Starting with 1.61 vs 1.67 high index lenses — the 1.67 lens is extremely thin whereas despite still being stylish, the 1.61 lens is extra-thin. The 1.67 lens is a great choice for extra-strong prescriptions.When working with large datasets in Excel, it’s essential to have the right tools at your disposal to efficiently retrieve and analyze information. Two popular formulas that Excel ...Aug 16, 2019 · The lens index describes the thickness of your lens. At Eyebuydirect, we use the following lens materials for these lens indexes: 1.5 – Plastic; 1.57 – Plastic; 1.59 – Polycarbonate; 1.6 – Plastic; 1.67 – High-index 1.74 – High-index LEARN MORE: Find the recommended lens index for your vision prescription. High-Index Lenses vs ... In today’s digital age, researchers rely heavily on various tools and databases to enhance their work. One such tool that has gained immense popularity among scholars is the Scopus...

Mar 19, 2024 · Assuming that light travels from air to glass, the angle of incidence is 30°, and the angle of refraction is 20°. To calculate the refractive index, follow these steps: Identify the refractive index of air: n ₁ = 1. Modify Snell's law to find the refractive index of glass: n ₂ = n ₁sin (θ₁)/sin (θ₂). Enter data: n ₂ = 1×sin (30 ...

An easy way to remember this: the higher the index, the thinner your lens will be. Thin – 1.61 Hi-Index (Basic) This lens material is suitable for prescriptions from +2.00 to -4.00 and astigmatism correction of -3.00 or less. 1.61 Hi-Index is on average 25% thinner than CR 39. Thinner – 1.67 Hi-Index (Better) However I'm worried that my high prescription (-5.50 right, -5.25 left) might benefit more from a higher index. (1.61 vs 1.67). Though that makes the lenses about $40 more expensive. These are about 55mm wide lenses, is there a way to estimate how thick the lenses would be? Am I asking too much out of these frames for such a high prescription? Starting with 1.61 vs 1.67 high index lenses — the 1.67 lens is extremely thin whereas despite still being stylish, the 1.61 lens is extra-thin. The 1.67 lens is a great choice for …Hi, I've decided to go for the cheap approach of getting lens with Zenni for my headset. When I selected the lens I was asked if I wanted to put blue light and UV block (Blokz) among other choices. At first, I was like "Hell yeah, protect my eyes from this demonic blue light !" but then I started to wonder if this would affect my …1.67 High Index Lenses are typically 35% thinner than ordinary CR39 plastic. 1.74 High Index Lenses are normally 50% thinner than ordinary CR39 plastic. High-index lenses can improve lens comfort and appearance, and may even open the entranceway to a larger variety of frames. High-index lenses may be just the answer you have been searching for.Nov 12, 2020 ... Uncut Glasses Side Thickness Compare 1.56 vs 1.60 vs 1.74 | Crizal 1.74 Lenses | High Index Lenses.High Index "necessary" for these kinds of frames? I've been trying to find semi-large circular lenses to little success, though I did find one pair that I actually liked. However I'm worried that my high prescription (-5.50 right, -5.25 left) might benefit more from a higher index. (1.61 vs 1.67). Though that makes the lenses about …

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Dec 7, 2023 · Overview of high-index lenses. High-index lenses are thin, lightweight lenses made from a special type of plastic. To be considered high-index, a lens must have a refractive index of at least 1.60. The higher the refractive index, the thinner the lens and the more effectively it bends light. If you have a prescription that is +4.75/-6.75 or below, you’ll benefit from the thinness of a 1.67 high-index lens. Strong prescriptions that are +5.00/-7.00 or above will work best with a 1.74. When you have a really strong prescription, a 1.74 high-index lens will be the thinnest option.Cons of 1.50 Lenses. Lower index of refraction: While the lower index of refraction in 1.50 lenses provides them with a wider field of vision, it also means that they are not as efficient in bending light. This can result in thicker lenses for individuals with higher prescriptions, leading to a less appealing aesthetic appearance.They currently come in indices of 1.61, 1.67, and 1.74. All three lenses are made with similar materials, so the choice of the index comes down to your prescription strength. A 1.67 high-index lens is best for +7.00/-9.00 or above. It can even be a good choice for people with low prescriptions who want the additional lens …ok, without bombarding you with boring science crap, go for the 1.67. A bit more info: the ABBE value difference between a 1.6 and a 1.67 will be negliagble and very nearly no-one would notice the decrease in optical "quality", however the difference in thickness would be noteworthy. A 1.67 will give a flatter front surface, and a …3 days ago · Birefringence is a measurement of the difference between the two refractive indices in gems that are doubly refractive, and it ranges from a low of .003 to a high of .287. The following chart lists the refractive indices for 215 varieties of gemstones. Refractive Index Chart of all Gemstones Gemstone If you were to compare them to a pair of glasses with Trivex lenses of the same prescription, you’ll find that high-index lenses are always thinner and even lighter in higher prescriptions. Weight High index lenses are lighter. Trivex lenses have a lower refractive index of 1.53 as compared to high-index lenses having 1.67 to 1.74. The most common high index options are 1.61, 1.67, and 1.74. These numbers represent the refractive index of the lens material. If your prescription power is …Standard lenses are at an index of 1.50 while the highest options are between 1.74 and 1.90. The stronger your prescription, you can choose higher indexes allowing for incredibly thin lenses but for people within the average range of visual correction, your best bet will be between the 1.59 and 1.67 range. The Mid-Range of High Index LensesFeb 25, 2021 · High-index lenses are available in a vast range of indices, all of which can be found in the range of 1.53 to 1.74. Lens index is determined by a measurement of light refraction and lenses with a refraction index of 1.70, or higher are up to 50% thinner than standard plastic lenses. Determining which lens is right for you can be a bit confusing ... ….

1.67 High Index 1.67 high-index lenses surpass in thinness and lightness when compared to 1.61 high-index lenses. It helps with eye distortion caused by stronger prescriptions and is ideal for individuals with an SPH correction between +/- 7.00 and +/- 9.00, and a CYL correction between +/- 3.25 and +/- 4.00.Jan 11, 2023 · In the most basic of terms, the higher the index of refraction, the more reflections the material creates, and the more the wearer would benefit from AR to minimize reflections. When comparing CR-39 to 1.74 …Buy High Index Lenses. Trivex has a low index of 1.53, similar to standard plastic. High index plastic’s index ranges from 1.67 to 1.74, making it considerably thinner and more lightweight than Trivex, especially in higher prescriptions. High index plastic has similar scratch resistance to Trivex.Your prescription is high. Go with the 1.67, for sure. Also, the frames you choose is equally important. Smaller and rounder is recommended to reduce the thickness of the lenses. I know you didn't ask, but there are some other things you should consider because your numbers are high... Try to get 2 numbers for PD, one for …Apr 4, 2022 ... If you have a mid to high prescription, stick to the thinner lens options at 1.67 index and 1.74, which is the thinnest and lightest of the two.The lens index describes the thickness of your lens. At Eyebuydirect, we use the following lens materials for these lens indexes: 1.5 – Plastic; 1.57 – Plastic; 1.59 – Polycarbonate; 1.6 – Plastic; 1.67 – High-index 1.74 – High-index LEARN MORE: Find the recommended lens index for your vision prescription. High-Index Lenses vs ...Dec 7, 2018 · If you have a prescription that is +4.75/-6.75 or below, you’ll benefit from the thinness of a 1.67 high-index lens. Strong prescriptions that are +5.00/-7.00 or above will work best with a 1.74. When you have a really strong prescription, a 1.74 high-index lens will be the thinnest option. The following table lists these values for selected gemstones. For gemologists, refractive index and double refraction ( birefringence) serve as important clues for identifying gems. The following table lists these values for a variety of stones found in jewelry and gem collections. Rubies and spinels may show similar colors. 1.61 High index lenses are up to 20% thinner than 1.50 Standard index lenses. 1.67 High index lenses are up to 30% thinner than 1.50 Standard index lenses. Stronger prescriptions: They are recommended for individuals with high myopia or hyperopia, providing optimal vision correction while minimizing lens bulkiness. It really depends on the size of the frame you want to buy. Smaller frames will show less of a difference between the two materials, and with a larger frame you will see a difference. 1.74 has a crappy Abbe value and produces visual distortion. Also, 1.74 is actually thicker than 1.67. 1.67 is better overall. 1.61 vs 1.67 high index, This guide discusses everything you need to know concerning the lens index and 1.57 mid index lenses, including standard or mid-index lenses, high index lenses vs. polycarbonate, and much more. 1.61 high-index lenses offer an ultra-thin option for all those looking for a modern, stylish look., Photochromic 1.67 Transitions VI. In response to customer complaints of slow-transitioning lenses, one of these improvements resulted in the release of Transitions® VI, a photochromic coating that allows up to a 40% faster shift in tint. This upgrade to standard transitional lenses also provides better UV protection …, Certain high index materials are available with the coating, but the nature of high index lenses often precludes the availability of transitional lenses. Not all manufacturers combine the two formats – especially on the higher-end high index materials like 1.80 or 1.90 glass lenses. If you want transition high index lenses you’re more ... , When working with large datasets in Excel, it’s essential to have the right tools at your disposal to efficiently retrieve and analyze information. Two popular formulas that Excel ..., Both 1.67 and 1.74 high-index lenses can accommodate strong prescriptions. The difference is in the thickness. 1.74 high-index lenses are up to 10% thinner than 1.67 high-index lenses. As a reference, 1.67 high-index lenses are recommended for strong prescription with an SPH correction between +/-7.00 and +/-9.00, and a CYL correction …, Feb 22, 2023 · There are a number of different lens index lenses available, with some better suited to certain prescriptions than others. You’ll generally find lens index in the following sizes: 1.5 Standard. 1.56 Mix-Index. 1.57 Thin and Light Index. 1.59 Standard Polycarbonate and High Index. 1.74 High Index Lenses are the thinnest and lightest. , OD: -2.50 -0.75 * 178. OS: -4.25 -1.25 * 005. The optometrist suggested that I pick between 1.61 and 1.67, so I purchased 1.67 Zeiss AS DP lenses for 49 []21 glasses since I figured that the thinner the better... was this overkill? After I got home I'm reading through ABBE values and eye strain due to higher index lenses and I'm getting cold feet., Our 1.74 high index lenses are offered at a more affordable price with a long list of value adds: anti-scratch, and 100% UV protection. Available at $69.95. Our 1.74 high index digital free form lenses use leading technologies in the eyeglasses market. Now at $79.95. Our 1.74 digital free form progressive (no-line, multi-focal) lenses …, They currently come in indices of 1.61, 1.67, and 1.74. All three lenses are made with similar materials, so the choice of the index comes down to your prescription strength. A 1.67 high-index lens is best for +7.00/-9.00 or above. It can even be a good choice for people with low prescriptions who want the additional lens …, Polycarbonate 1.59 Lenses: The most impact-resistant lenses for eyeglasses. They are 22% thinner than standard lenses and are recommended for children and sports, as well as prescriptions of +/- 4.00. 1.6 Index Lenses: High index lenses up to 25% thinner than the standard lenses. Recommended for prescriptions of -4.00 to +3.00., Your prescription is high. Go with the 1.67, for sure. Also, the frames you choose is equally important. Smaller and rounder is recommended to reduce the thickness of the lenses. I know you didn't ask, but there are some other things you should consider because your numbers are high... Try to get 2 numbers for PD, one for …, Most polycarbonate lenses have a refractive index of 1.59. This figure means that they can be around 10 percent thinner than other lenses, including glass. By contrast, 1.67 high-index lenses are about 30 percent thinner and lighter, and 1.74 single-vision lenses are 35 percent thinner for the same prescription strength. , EASY View (Instinctive) 1.67 High Index 1 – 3 EASY ... N88 L6738 SYNC SF P EAS V (INST) 167 HC –B- Country of Origin required on Label US FDA disclaimer Required 2. Product Range: Nominal Diameter (mm) Nominal Base Curve (D) Add Power Range (D) Recommended Rx, MATERIALS. 1.5 CR39. The most commonly used lens material is economical and durable as well as offering the best Abbe value of all the lens indices. We always recommend, where practical, to dispense the CR39 material. Although the optical corrective properties of the 1.5 is superior to other indices, for high plus or minus prescriptions the lens can …, Mar 19, 2024 · Assuming that light travels from air to glass, the angle of incidence is 30°, and the angle of refraction is 20°. To calculate the refractive index, follow these steps: Identify the refractive index of air: n ₁ = 1. Modify Snell's law to find the refractive index of glass: n ₂ = n ₁sin (θ₁)/sin (θ₂). Enter data: n ₂ = 1×sin (30 ..., 1.67 High Index Lenses are typically 35% thinner than ordinary CR39 plastic. 1.74 High Index Lenses are normally 50% thinner than ordinary CR39 plastic. High-index lenses can improve lens comfort and appearance, and may even open the entranceway to a larger variety of frames. High-index lenses may be just the answer you have been searching for., What's the difference between 1.67 and 1.74 when it comes to high index lenses? Check out this video of Eyeglass Tyler from SportRx to find out! For even mor..., I have a +4.25 prescription, should I get 1.67 or 1.74 index lenses for glasses? Would there be any noticeable difference in thickness? I'm also concerned about the distortion/warping - my current pair is just a standard lens (not high-index) and there is a noticeable warping effect when looking at my eyes from a side angle, I think this is due to how thick the …, High Index Lenses Thickness Comparison: 1.60 High Index Lenses are on average 20% thinner than ordinary CR39 plastic. 1.67 High Index Lenses are on average 35% ..., Dec 6, 2021 · In this section, we will show you the differences between 1.67 high index lenses and 1.74 high indexes. 74 high index lenses are thinner and lighter than 1.67 high index lenses. 74 high index lenses are expensive than the 1.67 high index lenses. Both 1.67 and 1.74 high index lenses can reduce the eye distortion caused by strong prescriptions, 1 ... , Glass lenses available from ThinLenses. 1.5 Glass High Index Lenses £ 82.00. 1.7 Glass High Index Lenses £ 146.00. 1.8 Glass High Index Lenses £ 223.00. 1.9 Glass High Index Lenses £ 274.00. All our lenses come with free anti reflective coating, scratch resistant coating and UV400 coating., Eyeglass professionals recommended them for people who look modern with a prescription of +/- 4.00 to +/- 6.75 and CYL correction between +/- 2.25 to +/- 3.00. 1.67 Ultra High Index. Ultra-High index lenses are made of a dense material, which allows them to block 100 percent of UV rays and resist scratches., Standard lenses are at an index of 1.50 while the highest options are between 1.74 and 1.90. The stronger your prescription, you can choose higher indexes allowing for incredibly thin lenses but for people within the average range of visual correction, your best bet will be between the 1.59 and 1.67 range. The Mid-Range of High Index Lenses, What is the difference between a 1.74 high index lens and a 1.67 high index lens? That's what's discussed in this video. If you have any more questions or ar..., • 8 yr. ago. HereComesBadNews. Is it worth going from 1.61 high index to 1.67? I wear glasses exclusively, no contacts, and because I'm an English professor (and I read all …, Nov 3, 2023 · Durable: High index lenses are typically made of materials that are more resistant to scratching and breaking. Choosing the Right High Index Lenses. Zenni offers high index lenses in a variety of indices, Hi-index 1.61, 1.67, and 1.74. The higher the index, the thinner the lens. Your choice of index largely depends on your prescription level. , Suitability for High Prescriptions. For those with higher prescriptions, 1.67 high-index lenses are often recommended due to their ability to bend light more efficiently, resulting in a thinner lens. Trivex, while not as thin, still offers a lightweight solution with added durability., Generally, lenses with an increased index of refraction will be thinner than lenses with less index. The refractive index of high index plastic lenses ranges from 1.53 to 1 1.74. Those in the range of 1 1.53 to at least one 1.59 are about 20% thinner than regular plastic lenses, whereas 1.74 high index lenses… , February 16, 2022. With the ever-increasing advancements in lens technology, there are more choices than ever when it comes to purchasing eyeglass lenses. Standard, …, As of this review, there are over 800 options for Men, over 1,100 options for Women, just under 100 options for Boys, and over 100 options for Girls. Pricing is all over the place depending on the desirability and material of the frames, but the prices start as low as $6.95 and go as high as $45.95 (that’s the most …, The most common types of high-index lenses have refractive indexes of 1.61, 1.67, and 1.74. What’s the Difference Between High-Index and Polycarbonate …, 1.67 High Index. The 1.67 High-Index lenses are 30% thinner than 1.50 Standard Index lenses with the same prescription. For higher prescriptions, this lens material and index works well due to its reduced weight and edge thickness. 1.74 High Index. 1.74 High-Index lenses are the thinnest and lightest lenses you can buy from …, However I'm worried that my high prescription (-5.50 right, -5.25 left) might benefit more from a higher index. (1.61 vs 1.67). Though that makes the lenses about $40 more expensive. These are about 55mm wide lenses, is there a way to estimate how thick the lenses would be? Am I asking too much out of these frames for such a high prescription?