Abstract
Objective: The aim of this study is to investigate the legibility of Hangul characters in two situations; moving characters and moving observers. Background: The legibility study of Hangul has been primarily focused on the case in which a static observer reads static characters. With the advent of kinetic typography, characters have begun to move, and drivers have to read road signs while moving. Research on legibility of Hangul in a moving situation is needed. Method: In order to compare the legibility of Hangul in the context of observer movement and Hangul movement, the character size (visual angle of character = $2.5^{\circ}$, $5.5^{\circ}$, $8.5^{\circ}$), the reading time (1 Sec. 2 Sec. 3 Sec.), and the difficulty of the letter (the number of stroke in a character = 1~5, 6~10, 11~15) were set to be the same and the legibility was compared. Results: Under the same experimental conditions, the reading rate of moving observers was higher than that of moving letters. In both situations, the reading rate increased as the letter size and reading time increased and the difficulty of letters decreased. In the case of moving characters, the reading rate sharply changed with the change of the character size and the difficulty of the character. On the other hand, moving observers did not change sensitively to these changes. Conclusion: In contrast to the situation where moving observers read Hangul characters, the reading rate of the kinetic typography is sensitive to the difficulty of the character and the size of the character. Therefore, when designing the kinetic typography, it is necessary carefully to adjust the size and difficulty of the characters in consideration of legibility. Application: The results of this research will be helpful in designing kinetic typography and designing Hangul typography which should be read by moving observers.