Assessing legibility of Thai universal design typeface and Roman-like Thai typefaces across different viewing distances

Abstract

This study compared the legibility of the Thai Universal Design typeface (FT Manifest UD) with that of two Roman-like Thai typefaces (DB Ozone and Sukhumvit Tadmai) across multiple viewing distances. Using a distance threshold methodology, thirty-one Thai participants of diverse ages and visual acuities identified 36 Thai consonants at 15 distinct viewing distances. Statistical analysis using the Wilcoxon Signed Ranks Test revealed that FT Manifest UD significantly outperformed other typefaces in overall legibility (p < 0.05), with 24 of 36 letterforms showing superior legibility.

Keywords

• Universal Design Font
• Roman-Like Thai Typefaces
• Legibility
• Letter Features
• Multi-Viewing Distances