Evaluation of angular digits and comparisons with a conventional set

Abstract

"A new set of digits designed to make maximum use of easily discriminated forms was studied. Data on confusion errors are given. The legibility of the new digits is not independent of whether they are presented as black ground. At low illumination levels white on black is more legible, the reverse being true at high illumination levels. Comparisons with a conventional set, the Mackworth digits, at different illumination levels, exposure times, and angles of view, show the new set to be significantly more legible under all of these conditions." (PsycInfo Database Record (c) 2025 APA, all rights reserved)