Conversion Relationship Of Eye Chart

Let us first understand the concept of diopter. The degree of myopia in people's mouth is closely related to the diopter. 1 Diopter is defined as the focal point of light passing through the lens one meter behind the lens. Expressed in D, f represents the focal length and there is a formula D=1/f. If the focal length of the lens is 0.5 meters, then the diopter of the lens is 1/0.5=2. It is customary to call this 200 degrees.

Many friends want to clarify the relationship between the visual acuity on the eye chart and the refractive power (myopia). In fact, these two concepts are independent of each other, and there is no absolutely accurate conversion relationship between them.

Generally speaking, people with refractive errors have poor vision. The higher the refractive power, the lower the naked vision. But this is not absolute. Some people do not have high refractive power, but their vision is very low, because it is not only the refractive power that affects the quality of vision. If there are other diseases of the eye, or the retina imaging function, the optic nerve function is damaged, etc., the vision will also be reduced. The same diopter does not mean that vision cannot be changed, so friends with myopia do not need to be too discouraged. Use reasonable interventions, use eyes reasonably, and slowly develop good eye habits, which may make you get rid of glasses and restore vision.