Textures Suitable for Tactile Bar Charts on Capsule Paper

Abstract

To find suitable textures that fill the bars of tactile bar charts created on capsule paper, we conducted tactile exploration experiments with blind persons as participants. In the experiments, we prepared 12 textures filling the bars: four colors (black, dark gray, pale gray, and white) and eight dot patterns with various dot sizes and pitches. We asked the participants to count the number of bars in the graph (Experiment 1) and to count the number of bars that extended over a designated grid line (Experiment 2). The difference among the textures were conspicuous in the results of Experiment 1. Black and dark gray colors and the dot patterns whose inter-dot spacings were 1.5 mm or less needed short exploring times and gained high ratings. These textures were concluded to be suitable to fill the bars. In contrast, white and pale gray colors and the dot patterns whose inter-dot spacings were 2.0 mm or more needed long exploring times and gained lower ratings.