A New LogMAR Vision Chart: Jin`s Vision Chart

ABSTRACT

A new vision chart has been developed. This chart utilizes geometric progression of optotype size instead of arithmetic progression. The optotype is increased or decreased in its size by 1.25X (0.1 log unit) when a line changes. It becomes double or half by change of 3 lines. this principle is based on the suggesstion of International Standard Organization (ISO 8596). There are 3 kinds of vision chart; each one for adult, for children and landolt`s ring chart. They are available in one set. The basic distance for examination is 4 m, but it can be used in 3.25, 5and 6.25m. Five optotypes are arranged in each line, and the corresponding visual acuity is given when more than 3 letters are recognized correctly. The correlation coefficient when compared to ladolt`s ring chart were 0.88 with adult chart and 0.91 with children`s chart.