Character legibility 2: Legibility and reading speed

摘要

To determine the character sizes suitable for comfortable reading, we compared the legibility of sentences and the reading speed. We used reading materials with several font sizes (from 4 to 30 point of Microsoft Mincho). In Experiment 1 participants evaluated the legibility for Japanese sentences with the questionnaire.The legibility increased with the font size between 4 and 12 point. In Experiment 2, we extended the font size up to 30 point, and found the legibility decreased with thatbetween 20 and 30 point. In Experiment 3 participants read aloud Japanese sentences as fast as they could(with no errors). Reading speed in creased with the font size between 4 and 6 point, but did not increased with that between 6 and 15 point. Together with our previous findings, we concludethat character sizes suitable for comfortable reading are approximately between 10 and 20 point (visual angle 0.46-0.92° ).