Visual acuity chart is an important tool in ophthalmic clinic and vision research. This paper aims to expound the misunderstanding of vision records and the vision statistical issues in some of the research papers， and to further interpret the core design of visual acuity chart. This would be helpful to make the use of visual acuity chart more scientific and standard， and to get more accurate visual records and statistical results， so as to make the visual acuity chart to be better served in the vision screen， ophthalmic clinic， and vision research.