Are all eye charts the same?

The purpose of the eye chart is the same, is to check people's vision, check people's vision is mainly to check people's visual acuity, visual acuity inspection is mainly to observe the distance between two points of an object to judge the smallest angle, the smaller the angle, the better the vision. Most eye charts are designed according to this principle, but there are various ways of expressing this eye chart, such as the current fractional eye chart, the international logarithmic eye chart, and the Snellen eye chart. The multiplication degree of the visual target is not exactly the same. At present, the international logarithmic eye chart and the Snellen eye chart are commonly used. Like the multiplication rate of the Snellen eye chart, they can better express the normal vision of this person.