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Computer mice for the blind

Feeling in the dark

Nov 25th 2009

A tactile mouse helps blind people to use the internet

Tactile World

COMPUTERS have become such an integral part of life, in the rich world at least, that even social networking is done online. The blind, however, are often excluded from such interactions. Now a system has been developed to make it easier for blind people to navigate the internet, use word-processing software and even trace the shapes of graphs and charts. Its inventors hope it will enable more blind people to work in offices.

The system developed by staff at Tactile World, an Israeli company, uses a device that looks similar to a conventional computer mouse. On its top, however, it has two pads, each with 16 pins arranged in a four-by-four array. Software supplied with the mouse translates text displayed on the screen into Braille.

In traditional Braille, numbers and letters are represented by raised bumps in the paper of the page being read. The pins on the mouse take the role of these bumps. As the cursor controlled by the mouse is moved across the screen, the pins rise and fall to represent the text across which they are moving. One pad represents the character under the cursor, the other gives the reader information about what is coming next, such as whether it is a letter or the end of the word. This advance information makes interpretation easier. As the user reads the text, the system also announces the presence of links to other websites. And the user can opt, if he wishes, to have the computer read the whole text out loud.

The mouse’s software has an “anchor” feature, to hold onto the line of text that is being read. Alternatively, a user can click a button on the mouse and the text will scroll along and run under his fingers without him having to move the device.

When he encounters a graph, map or other such figure, the pins rise when the mouse is on a line. The number of pins raised reflects the thickness of the line. If he strays from the line, the pins fall. He is thus able to trace, say, the curve of a graph or the border of a country. More complex diagrams can also be interpreted. Dark areas of maps, for example, can be represented by raising all the pins, while light areas are places where all the pins are dropped.

Not only is the tactile mouse more advanced than existing technologies for blind people, it is also cheaper than existing Braille readers, which plug into a computer and typically display 40 Braille characters at a time. The tactile mouse costs $695, rather than $3,500-8,000 for a Braille reader.