Optimum letter size for a given display area

Abstract

"Visual acuity determinations were made on two groups of 20 subjects each at two luminance levels with three conditions of surround, or field clearance, above and below the line of letters… . It is concluded that, when space limitations are a consideration, letters should be made as large as possible up to the point of very nearly filling the available space (margin less than the stroke width of the letters), in order to permit discrimination at a maximum distance." (PsycInfo Database Record (c) 2025 APA, all rights reserved)