Should active hand movements be included when using a single cell sliding braille display?

The aim of this study is to quantify the contributions of active and passive movements to the design of single cell displays for the visually impaired. A single cell sliding prototype braille display was used to compare active movement and passive movement of the user in tasks of reading letters and simple words formed from braille characters. Twenty visually impaired individuals were tested in letter and word reading tasks under two feedback conditions of hand movement (active and passive) using the prototype. In the reading of letters, there was a significant reduction in reading speed and a significant increase in error rate under the active condition in comparison to the passive movement. However, in the more complex task of reading words under the two feedback conditions, the results demonstrated no significant differences in error rates. There was a significant reduction only in reading speed when allowing for active hand movement in the design. These findings suggest that single cell sliding displays that necessitate active hand movements in their design are likely to be less effective in terms of reading speeds of braille.