The effect of instrument dial shape on legibility

Abstract

The legibility of 5 types of instrument dials was measured in terms of accuracy of readings made by 60 male college student subjects. In order of accuracy, the dials ranked (1) open-window; (2) round; (3) semi-circular; (4) horizontal; (5) vertical; the percent of errors varying from .5% to 35.5%. Errors on all dial types were more frequent on mid-division than on whole-number settings. A brief history of the problem and detailed explanation of the experimental design and the apparatus used are given. 30-item bibliography. (PsycInfo Database Record (c) 2025 APA, all rights reserved)