Contact lenses can only provide correction and do not change the size of the field of vision, so why do people feel that things get bigger after wearing contact lenses?
In fact, the short-sighted frame mirror itself is a concave lens, which will cause the object to look smaller according to its imaging principle. Moreover, for every 100-degree increase in the degree, the object image will shrink by about 2%, so patients with high myopia see a higher degree of distortion of the field of view through the frame mirror. At the same time, due to the increased thickness of the lens, it will also increase the pressure on the bridge of the nose.
The contact lens is attached to the cornea, and there is almost no distance between the eyeball and the lens, so there is no problem of distortion. For those who are accustomed to wearing spectacles, they will feel the obvious effect of increasing the field of view, but contact lenses only reflect the real image and do not enlarge the image of the object. However, contact lenses have relatively high requirements for hygienic conditions and wearing environment, and need to be worn correctly according to the instructions. Improper operation can easily cause eye diseases.
Although both contact lenses and frame glasses are products for correcting vision, in addition to the difference in visual field effect, the degrees of the two are also somewhat different. Generally speaking, within 400 degrees, the degree of frame glasses can be directly used to match contact lenses, but if it exceeds 400 degrees, it needs to be converted. In short, the higher the degree, the greater the degree gap between the two.
Frame glasses have no risk of infection and do not need to control the wearing time, while contact lenses are better in terms of convenience and portability, so you can also combine them and wear them alternately to meet more diverse occasions and needs.