Heterogeneous visual acuity chart and visual acuity testing method and device

Abstract

A heterogeneous visual acuity chart and a visual acuity testing method and device are provided. The heterogeneous visual acuity chart is a size illusion chart composed of a heterogeneous reference zone and at least two types of optotypes of different sizes, where the heterogeneous reference zone is used to cause incorrect identification on the different types of optotypes of different sizes. The visual acuity testing method and device determine whether a visual acuity of a subject is true based on a difference between visual acuities tested with the heterogeneous visual acuity chart and a standard logarithmic visual acuity chart. The visual acuity chart is a size illusion chart composed of optotypes of different sizes and a perspective, which causes an illusion on a visual depth to interfere with the identification of the optotypes of different sizes.

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