03 February 2009

Louis Braille

I owe significant part of my salary to Louis Braille who turned 200 last week.

You probably know that he invented the system for printing documents so that blind people can read the raised dots on the paper. They're formatted as 3 rows of two dots:

1 4
2 5
3 6

With my job at an accessibility technology company (I help program Window-Eyes, a screen reader so that blind or people with low vision can use computers. We have other products that are more mobile than a PC.) I've learned more about Braille than just that. For example, the way that you can tell that the document is upside down is that it feels like nonsense. Also, depending on exactly the shape of the dots and the paper's characteristics, some printing may be very difficult to read even though it is formatted correctly.

A couple other interesting properties of Braille are that every letter has a dot in the top row. I used to think that there were 64 possible characters for each position of Braille 2 x 2 x 2 x 2 x 2 x 2 or 26- two choices for each place. That's not actually the case. Because every letter has a dot in the top row, there are only 3 possibilities for the two cells in the top row. which cuts down the number of possibilities to 48. Numbers are an exception and they are the first 10 letters shifted down one row. There are special marks for capitalization and punctuation.

Also, Braille has a system known as grade 2 which abbreviates syllables and phonemes to reduce the number of characters that text takes up. Other languages have variants of grade 2 and of the alphabet.

How does that pay part of my salary? Several companies make devices with cells of 6 or 8 pins simulating the dots of a single character of Braille. (the extra two dots on the bottom extend the possibilities.) Window-Eyes controls the cells on these Braille display so that any letter can be placed in any position dynamically. One of my sub-projects is to extend and maintain our software that converts what we speak into commands for the Braille display driver.

We can also display what is on the display textually on the computer screen. Since I don't know Braille I need a chart to look at the pins visually to find letters beyond the short list that I already know. It would impossibly impede my development. The text makes it possible for me to work without needing the help of one of our employees that can read Braille to do my work with Braille.

Without Louis Braille, there would be no Braille and besides the tragedy that that would be for so many people, I wouldn't be able to enjoy creating Braille dynamically.

Tangentially, this relates to stamp collecting and numismatics because some countries are making stamps commemorating the day. (I saw on another stamp collecting blog that Ireland is one of those countries.) Also, the U.S. has plans to release a silver dollar collectible in a couple of months for the event.

-- Bill


  1. India released a braille stamp on Louis Braille recently ..check out here on my blog..please let me know how you like it


  2. That is a very good stamp and I appreciate the description. It includes a lot of information about Louis Braille that I didn't know.