Foveal acuity, peripheral acuity and search performance: A review

Some of the more important results from 30 years of research on foveal and peripheral acuity, visual search performance and the relationships between them are summarised in this paper. The visual lobe area is a useful concept for representing peripheral acuity and has proven to be important in predicting performance for visual search tasks. Different approaches to measuring lobe area and experimental results relating peripheral acuity and visual search performance are summarised. Methods of measurement include full field mapping, eight-axis visual field mapping, four-, two- and one-axis lobe length measurement, and a card-sorting task. A brief review is also made of the various measures of static and dynamic foveal acuities using different types of tasks, their applications and factors affecting acuity values.