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What are high index lenses?

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  • Nadine


    High index lenses are primarily designed to be used by patients that have a prescription in the range of -3.50 or stronger. Although this isn't an absolute and there are other factors in an individual's prescription that can influence this choice as well, we feel that the benefits seen by those patients are worth the extra cost of a high index lens.High-index plastic lenses come in a wide variety of "indexes", with the most common being 1.67 and 1.74. Lenses with a refractive index of 1.67 will typically be about 40% thinner than a standard plastic lens and 1.74 lenses will be about 50% thinner that a standard plastic lens.We typically recommend that patients with a -3.50 or higher should select a 1.67 high index lens while patients with a -7.00 or higher should select a 1.74 high index lens for the best optical experience.
  • Nana


    High-index lenses are an alternative choice to standard, plastic eyeglass lenses. Although high-index lenses are more expensive than plastic lenses, they can reduce the thickness and weight of an eyeglass lens, particularly for individuals with a strong prescription. For most prescriptions, high-index lenses offer the same optical clarity as plastic lenses in a significantly smaller package.
  • Yuana


    High-index lenses are advanced plastic lenses that are thinner than conventional plastic or glass lenses. High-index refers to the lens materials index of refraction. A lens material's index of refraction describes the degree to which it refracts light. A high-index material has an index of refraction above conventional plastic (1.499). The higher index of refraction enables the material to bend light to a greater degree. This results in a thinner lens because less curvature is needed for a given power. In addition, high-index lenses are generally lighter than plastic because they require less material to produce the lens. In simple terms, this means that a high power can be captured in an ultra-thin lens that's very light and attractive
  • ella


    High index lenses are specifically designed to be flatter, lighter in weight, and thinner than other lens materials.They are available in single vision and progressives lenses styles. High index lenses material is lighter and thinner than conventional glasses or plastic, and is an excellent option for strong prescriptions. High index lenses have a UV filter and scratch resistance built into them by the manufacturer. They are available in fashion tints. sunglasses tints.