Display of Virtual Braille Dots by Lateral Skin Deformation: A Pilot Study

When a progressive wave of localized deformations occurs tangentially on the fingerpad skin, one typically experiences the illusion of a small object sliding on it. This effect was investigated because of its potential application to the display of Braille. A device was constructed that could produce such deformation patterns along a line. This enabled us to test blind subjects’ ability to read the truncated Braille characters ‘◦◦’, ‘◦•’, ‘•◦’, and ‘••’. While subjects could identify two-character strings with a high rate of success, several factors need to be addressed before a display based on this principle can become practical.