How to convert the degree of contact lenses?

There are many parameters of contact lenses, and some are related to the wearing effect and some are related to the wearing experience, so you should understand before purchasing lenses. Today, I will briefly introduce the main contact lens parameters, so that everyone can choose and choose.

Moisture content is the proportion of water contained in the lens. For the lens, the higher the water content, the more hydrated and soft the lens, and the higher the oxygen permeability. However, it cannot be simply understood that the higher the water content, the better, and the water loss of high water content lenses is faster. Therefore, people with less tear secretion should try to choose low water contact lenses.

The base arc refers to the radius of curvature of the lens, that is, the degree of curvature of the lens. The larger the base arc, the flatter the inner surface of the lens. If the base arc of the lens does not match the base arc of the eyeball, there will be problems with the sliding plate or the eyeball. When the values ​​of the two base arcs cannot be completely matched, it is only necessary to select a slightly larger base arc of the lens within the difference of 0.2mm.

Oxygen permeability is often used to judge the quality of contact lenses, which is a parameter indicating the degree of oxygen permeability of contact lenses. In order to maintain corneal respiration, contact lenses must have extremely high oxygen permeability. The oxygen permeability is related to the lens thickness, water content and the material of the lens itself. There is no doubt that for contact lenses, the higher the oxygen permeability, the better.

The choice of degree is relatively simple, but it should be noted that the degree of contact lenses and frame glasses is not consistent, and the formula needs to be used to convert. In order to get an accurate degree, it is best to have a professional optometry examination, and, if there is a problem of astigmatism after the examination, you need to wear astigmatism contact lenses for correction.

Although there are many parameters of contact lenses, after understanding, you can find that there is not much difficulty in purchasing. I hope this knowledge can be helpful to everyone.