1 Eye Hospital, Wenzhou Medical University, Wenzhou 325027, China 2 Center for Neural Science, New York University, New York 10003, USA 3 CAS Key Laboratory of Behavioral Science, Institute of Psychology, Chinese Academy of Sciences, Beijing 100101, China 4 Department of Psychology, University of Chinese Academy of Sciences, Beijing 100049, China 5 Division of Arts and Sciences, NYU Shanghai, Shanghai 200122, China 6 NYU-ECNU Institute of Brain and Cognitive Science at NYU Shanghai, Shanghai 200062, China
Abstract:Vision is one of the most important human senses. Visual acuity, usually measured with acuity charts, quantifies the spatial resolution of the visual system, and is the most commonly used functional vision measure in clinical practice. Precise evaluation of visual acuity is of great importance for clinical and occupational health screening. In this paper, we briefly review the history of visual acuity charts, including the design principles and scoring rules of two of the most popular acuity charts, the Early Treatment of Diabetic Retinopathy Study (ETDRS) chart and the Standard Logarithmic Visual Acuity chart. Computerized visual acuity tests have emerged in recent years because of the inherent limitations of acuity charts,including low precision and large learning effects. We analyzed the hardware requirements, algorithms and performances of a range of computerized tests and found that the differences in parameter settings and test protocols made it impossible to compare acuity scores across different computerized tests. Therefore, there is an urgent need to standardize computerized visual acuity tests.
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