The difference of refractive index brings different visual effects

1.56 and 1.61 refer to the refractive index of the lens. Generally, when selecting the lens in the matching, we will see the refractive index of different lenses, and these refractive indexes are an important part of the lens parameters. General high myopia is more suitable for choosing high refractive index lenses. Then, what is the difference between lenses 1.56 and 1.61?

Difference between 1.56 and 1.61 lenses:

First, let's learn about the refractive index of the lens. Under the same material and the same degree, the higher the refractive index of the spectacle lens, the thinner the lens will be. Therefore, for high myopia, the lens with high refractive index reduces the weight of the lens and improves the beauty of the lens. Of course, lenses with high refractive index are usually more expensive than lenses with low refractive index. The larger the number, the higher the refractive index and the more expensive the price.

Difference between 1.56 and 1.61 lenses:

At present, resin lens is the most widely used. The refractive index of resin lens is generally 1.49, 1.56, 1.61, 1.67 and 1.74. Generally, under the same material and degree, the edge of high refractive index lens is thinner than that of low refractive index lens. Therefore, when the material and degree of lens 1.56 and 1.61 are the same and the curvature design is the same, The lens edge of 1.56 is thicker than that of 1.61.

1.56 lens belongs to medium refractive index lens, including both spherical design and aspherical design. 1.61 lens is high refractive index lens, only aspherical design. Aspheric lens can reduce the phase difference at the edge of the lens and make the field of vision clearer and more natural. For the general myopia group with high degree, it is more suitable to choose aspheric lenses with high refractive index. The refractive index parameters of myopia lenses can help you better choose lenses. For example, for 500 degree myopia, you can choose either 1.56, 1.61 or 1.67, but those with high refractive index will be thinner and more beautiful.