Braille is the universal system of writing by the blind. Invented in France by Louis Braille. It has been used by the blind of the world for over 150 years. This paper will put forth a proposed standard for the encoding of the braille writing system for use in ASCII and Unicode based computer equipment.
The Braille System
All braille used by countries using the roman alphabets is based on the same system. That is a six dot cell arranged in two vertical rows of three dots each. Any combination of these dots my be raised. Therefor it is possible to produce braille in any roman alphabet using language with only one encoding system.
The Encoding
Below is listed the encoding for braille one the english keyboard. Unlike traditional encoding systems braille will be dependent on the being in the same physical location on the keyboard rather than being assigned slots in a table as is done with print.
English Encoding
ASCII Hex Octal Braille Name
f 66 146 dot one
d 64 144 dot two
s 73 163 dot three
j 6A 152 dot four
k 6B 153 dot five
l 6C 154 dot six
(space) 20 040 space
Braille Fonts
Braille fonts have as can be seen above only seven assigned slots on the table which are placed in the same relation to each other no matter what the language of the keyboard is. Braille font also are unique in that they have no character width and that they come in one fixed size that being 36 points*. The cell sets are made up by pressing combinations of the assigned letters at one time. Thus on english keyboard the braille letter c would be don by pressing the keys f and j at the same time. A space would then be pressed to move to the next cell. After a word the user would enter two spaces. (Included with this document is a sample font complying with this specification.)
Unresolved Issues
Issues left unresolved by this first draft are as follows:
Eight dot braille, used in non-roman alphabets
Eliminating the need for the space after each character
The ability to print braille representation using PostScript¬ outlines which do not seem to accept character of 0 charwidth. (Sample outline fonts in type one are included with this document.)
This is a first draft of this specification we invite your comments and suggestions. Please mail them to:
Greg Kearney
Touchstone Software
1641 South Nebraska
Casper, Wyoming 82602 U.S.A.
or call (307) 266-0570 weekdays 9 to 5 Mountain Time
*the exact physical size will be specified at a latter date.
