Mid index lens
The 1.57 mid-index lens is best for prescriptions +2.00/-3.75 or below. It also features 100% UV protection. It’s the thickest lens that is recommended for prescription with SPH – 2.5, +2.5 and below. To prevent cracking of the lenses, go for full-rimmed frames. The CR 39 lenses are conventional plastic lenses. 1.56 Index – Mid Index Thin and Light Lenses . Convenient lenses for stronger prescription, they are 15% thinner than 1.5 index. Thinner, lighter and more expensive than mid-high index or hard resin lenses, high index lenses are a good choice for every day use. High Index Lenses - 1.70 and 1.74 Ultra High Index. High index lenses with 1.70 high index and 1.74 are the thinnest lenses on the market, and are made only for people with the highest prescriptions. High-index plastics allow for thinner lenses. The lenses may not be lighter, however, due to the increase in density vs. mid- and normal index materials. A disadvantage is that high-index plastic lenses suffer from a much higher level of chromatic aberrations, which can be seen from their lower Abbe value. 1.57 mid index single vision lenses means that the lens is thinner than standard plastic lenses. It is not the thinnest possible, nor is it impact resistant like Trivex 1.53 mid index lenses, or Anyone know what material the Zenni "1.57 mid-index" lens is? First, let me lay out this disclaimer: I just dropped $500 after insurance at my local brick and mortar optometrist on new glasses. I also bought about a months worth of daily contacts for them ( I wear contacts about 3-4 times a month). Lets leave the "you get what you pay for" off
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. It is lighter
The 1.53 mid-index Trivex lens is a polymer lens that is the most impact-resistant lens available. It covers the same range as the 1.57 mid-index lens: -4.00/+2.00 or lower on the SPH and +/- 6.00 or lower on the CYL. Thinner, lighter and more expensive than mid-high index or hard resin lenses, high index lenses are a good choice for every day use. High Index Lenses - 1.70 and 1.74 Ultra High Index. High index lenses with 1.70 high index and 1.74 are the thinnest lenses on the market, and are made only for people with the highest prescriptions. Several factors, including price, should weigh in your decision to use low index, mid index, or high index lenses. If your diopter number falls between 0 and +/- 2.00, the recommended index material is 1.50. If your diopter number falls between +/- 2.00 and +/- 4.00, the recommended index material is 1.56. Mid-index lenses are slimmer and lighter than standard plastic types. A variety of protective treatments can also be applied, including photochromic and no-glare coatings. Slightly stronger prescriptions for farsightedness typically require a thicker lens. I'm reading on Zenni that 1.61 High-Index Single Vision lenses are recommended. However, those cost an addition $20.00. I don't want to spend an additional $20.00 for a $6.95 pair of eyeglasses. I'd go with the free alternative of 1.57 Mid-Index Single Vision lenses.
Zenni, as example, sells very high index lenses (1.74) for about 80 USD upgrade cost. If you are already at -2.00 diopters or less, spending the extra money will make no noticeable difference for you. A mid index 1.57 is plenty in this -2.00 diopter scenario.
21 Feb 2014 Also free with single-vision prescriptions is the 1.57 mid-index lens. This lens is often described as “polycarbonate composite,” because in What does lens index mean? 1.50 Standard Index; 1.56 Mid-Index; 1.59 Polycarbonate; 1.61 High Index; 1.67 High Index Mid-index lenses are slimmer and lighter than standard plastic types. A variety of protective treatments can also be applied, including photochromic and no-glare The first step towards clearer vision is learning which lens index is right for you. Our chart explains lens indexes including 1,67 and 1.74 high index lenses. 1.57 mid index lens is a base lens, great for full rim frames where the lens is supported on all sides, but is not recommended for semi rimless or rimless frames
The first step towards clearer vision is learning which lens index is right for you. Our chart explains lens indexes including 1,67 and 1.74 high index lenses.
Mid-index lenses are slimmer and lighter than standard plastic types. A variety of protective treatments can also be applied, including photochromic and no-glare The first step towards clearer vision is learning which lens index is right for you. Our chart explains lens indexes including 1,67 and 1.74 high index lenses. 1.57 mid index lens is a base lens, great for full rim frames where the lens is supported on all sides, but is not recommended for semi rimless or rimless frames Most eyeglass wearers are nearsighted, which requires corrective lenses that are thin in the center but thicker at the edge of the lens. The stronger the prescription, trivexTrivex lenses are impact resistant lenses and are a lightweight, durable mid -index lens material that is considered an upgrade from its industry-standard
What does lens index mean? 1.50 Standard Index; 1.56 Mid-Index; 1.59 Polycarbonate; 1.61 High Index; 1.67 High Index
Super Thin Lenses (1.61 High Index lens)-It is suitable for prescriptions of Mid Distance Lens: If you mostly need these glasses to work before computer or Mid-Index: High index materials are classified by numbers. Again, the higher the number, the thinner and lighter the lens. The Mid-index lenses, such as 1.54, 1.56, and 1.57, are thinner than glass, and nearly as strong as CR-39. High-Index High index lenses, typically ranging from 1.53 to
Lens Index. The index of your lens, also referred to as the index of refraction or refractive index, is a number that indicates how efficiently the material bends, or refracts, light. The higher the refractive index of the lens, the more slowly light moves through it, and the more the light bends.