VISUAL ACUITY TESTING

摘要

An apparatus for testing visual acuity of a subject is disclosed. The apparatus includes control means (e.g. a digital computer) and display means (e.g. a computer monitor). The display means is controlled to display a series of symbols for attempted identification by the subject. The displayed size of the symbols is selected from a substantially continuous range, allowing fine measurements of visual acuity to be obtained by varying the displayed size of the symbols by small increments close to the visual acuity threshold of the subject.