A 7 year old should have a vision of 1.2 to be considered normal. But simply having a normal visual acuity of 1.2 is not entirely correct, because a child this age should have a better part of the farsighted reserve. Generally, a 7-year-old child should have a hyperopic reserve of 100-150 degrees, and the eye axis should be within the normal range, which should be 20.5-21.5mm. If a child’s visual acuity is normal to 1.2, but the hyperopic reserve is almost depleted and the eye axis does not match normal, it cannot be considered completely normal. If children do not pay attention to the correct use of the eyes, it is easy to myopia.