Texts for the blind - optimizing for screen reader and braille output
Is it possible to optimize texts for screen readers and Braille displays? Yes, of cause. If you follow some rules, you improve the reading experience for blind and visually impaired readers.
I wouldn't say that the importance of these recoomendations are very high, most blind persons have enough reading experience to ignore small failures in texts.
A new installed screen reader reads out all information like punctuation, spaces and so on. These informations are not in all cases necessary, most blind reduce the information output.
Nevertheless, interpuction and other details play an important role in the working of assistive technology. Modern screen reader uses the interpunction for the pronunciation.
Actual screen readers uses two working modes:
- Phonemes were combined according rules.
- On the other hand, there are dictionaries for many words, because in every language there are some exceptions from the pronunciation.
You might argument, that we can formulate dictionaries for all words. This is a good idea for reading software for persons with reading disabilities. But for screen readers it would be difficult because this will reduce its performance.
Difficult are formats, which defer from the standard. For example, the date is written different in many countries. Some uses hiven, some uses dots, some writes the year first, some the day or month. The screen reader not always knows how to speak it out right.
Interpuction offers different types of lines. It is important to use the right line for the right purpose. Many writers use the hiven to produce a minus or a dash.
What disturb many users is the strong use of the sign for copyright or trademark. The screen reader always reads the full information "Copyright" or "trademark", which disturbs the reading stream for the blind.
screen reader and Braille display only can represent signs, which they already know. Therefore you should avoid exotic signs.
You should avoid writing mistakes, because the screen reader don't know how to pronounce the words right.
The Braille display
There are to kinds of Braille: In full Braille, each visual letter is represented as one Braille letter. In contracted Braille ligatures, abbreviations, and contractions were used to increase the space and the reading speed like in shorthand. Writing errors can be the cause of a wrong representation of text on the Braille display.
For long composed words it is recommendable to use a space or a line to separate to words, this makes it easier for the Braille software to apply the abbreviations.
As already mentioned I don't think that this rules are very important. You should think about it but it is more important to avoid junk like Advertising, frames and recommendation buttons and so on which not only disturbs visually impaired persons but all users with reading disabilities.