The conventional Braille display state of the art and future perspectives

Abstract

Abstract. The conventional one-line Braille display is explained and discussed in great detail, the emphasis being laid on the ergonomic and sottware-technical aspects rather than the electronic or the electromechanical ones. Especially closely studied are the deeper aspects of text-based Braille display operation such as video attribute viewing and lightbar handling. In addition, some suggestions to improve present Braille display software are given, especially concerning the recently developed programs to access graphical user interfaces. What is Braille?The Frenchman Louis Braille (1809-1852) invented a writing system that is used by blind and visually impaired people and that is based on tactile rather than on optical perception. In original Braille, characters are generated by embossing small raised dots into a sheet of paper. Every Braille character occupies a small section of the sheet that is organized as a 2.3 grid and that can therefore take up to 6 dots. Every character (letter, number, punctuation mark etc.) is a certain selection within such a 2.3 arrangement, ff one includes the space -the character with no dot at all -, one thus obtains 2 to the 6th = 64 possible characters; it is therefore possible to represent the letters of the Roman alphabet together with the numbers, the punctuation marks and several special characters.Since its invention toward the end of the first half of the past century, Braille has been used by blind and strongly visually impaired people in two main ways: Firstly, special machines were devised that allowed a blind person to make personal notesthis made possible written communication between blind persons, however, at least in general, without the possibility to include sighted people. Secondly, by special printing methods literature was produced in Braille. What is a Braille Display?When, by the end of the seventies and in the beginning of the eighties, the computer became more and more the central medium of information processing in all areas of society, attempts were made to make the computer accessible for the blind by means of the Braille system. In these efforts, the conventional way to write Braille dots on paper proved totally inadequate; for most of the time the computer is operated interactively, presenting much information to the user that is relevant only for the

An exploratory study to improve reading and comprehending mathematical expressions in braille

“…The symbols and numbers are arranged at different heights above, on, and below the baseline to convey structure (Stöger & Miesenberger, 2015). Moreover, the symbols, numbers, and operators look very different from each other.…”

“…The representation in braille on a braille display is very different from the representation in print. Braille is a linear output modality (Stöger & Miesenberger, 2015) and all braille cells have the same size (Karshmer & Bledsoe, 2002). The transformation from an equation in mathematical notation to an equation in braille can be executed in two steps.…”

“…Mathematical structure is more difficult to grasp in braille than in print due to the linear representation in braille (e.g., Stöger & Miesenberger, 2015) and to the small perceptual view of braille readers (e.g., Millar, 1994Millar, , 1997. This does not mean that the level of detail is not present in the linear-braille expression or equation.…”