While purchasing contact lens, most people will focus on the color, diameter and disposal period. But few people pays attention to the base curve. Before wearing contact lens, if you inspect in a professional eye hospital, there includes the inspection of the base curve. Today, let us discuss about how to choose the base curve of contact lens in details.
Base curve（BC）refers to the radian of the contact lens. The bigger the base curve is, the more flat the internal surface of the contact lens is. While, the smaller the base curve is, the more curved the internal surface of the contact lens is. Base curve belongs to one parameter that reflects the actual conditions of the eyeball, which doesn’t influence the eyesight and there is no good or bad. Generally, the base curve of Asian people is between 8.4 and 8.6. The base curve of a variety of contact lens in the current market is also basically in this range. But, occasionally there is the situation that some parts of the people have relatively bigger or relatively smaller base curve.
Compared with the parameters that decide the quality of the contact lens such as the material, the base curve is not that important, but should not be neglected as well. The great difference between the base curve and the eyeball itself will bring some discomforts. If too big base curve, the contact lens and the eyeball doesn’t fit well, which makes the contact lens easily slide and makes the visual effect unstable as well. If too small base curve, it will impede the tear secretion, which makes the eyeball tight, swollen and causes the eye disease.
If you wear the contact lens now and feel relatively comfortable, then you could continue to purchase the same or similar product according to the base curve of the contact lens in use. Otherwise, you could decide whether fit or not through trying and pushing the contact lens. The contact lens is soft and a little bigger base curve could fit well the eyeball as well. But, smaller base curve is not recommended.
If you wear the contact lens on a long-term basis, the requirements on a variety of the parameters are relatively high. You must know well every parameter and choose suitable contact lens, which is beneficial for your eye health.