The grading of binocular blindness is divided into two types and five levels according to the criteria. For example, if the visual acuity of the better eye is less than 0.3, but the visual acuity of the worse eye is greater than 0.01, it is low vision level 1. If the visual acuity of the better eye is less than 0.1, but the visual acuity of the worse eye is greater than 0.05, it is low vision level 2. If the visual acuity of the better eye is less than 0.05, but the visual acuity of the worse eye is greater than 0.02, it is binocular blindness level 3. If the vision of the better eye is less than 0.02 and the vision of the worse eye is light perception, it is binocular blindness grade IV. Binocular blindness grade V is the absence of light perception in both eyes, which is the grading of binocular blindness.