Logarithmic visual acuity chart since its introduction in 1958, attracted the attention of the majority of domestic ophthalmologists and affirmation of its main point is: "statistics requires homogeneity to be compared. In the five-point method used to measure visual acuity of the visual standard, fingers, palms and light, accordingly, they measured visual acuity is not the same, that is, with the visual standard and finger check for the cone function, that is, the center of visual acuity. Logarithmic visual acuity chart instead of decimal system visual acuity chart is undoubtedly a great progress of vision examination technology. This standard applies to children and adolescents general physical examination, enrollment, recruitment and other physical examination of distance and near vision determination, clinical and other aspects should also refer to use.
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