If you thought that blind people cannot afford to use touch-screen devices like the iPhone, you are certainly mistaken, for scientists have now created a vibrating touch screen phone that can simulate Braille characters. In Braille, letters are encoded using a two-by-three matrix in which each character is represented by a different configuration of raised and absent dots at the six locations.
Taking a major step towards presenting Braille characters on a mobile device, Jussi Rantala of the University of Tampere in Finland and colleagues tried to display these dots on a touch-screen device.
The researchers used a Nokia 770 Internet Tablet, which has a piezoelectric material built into the touch screen that vibrates when an electric signal is applied to it.
The researchers installed software that represents a raised dot as a single pulse of intense vibration, and an absent dot as a longer vibration made up of several weaker pulses.
In order to gauge how visually impaired volunteers would prefer to receive these vibrations, the team developed two different presentation methods.
The first method required the users to touch the screen on the left-hand side to read whether or not there is a bump in that position of the matrix, and then they would move their finger horizontally across the screen to read the remaining five dots.
‘But it wasn’t that easy to read,’ New Scientist magazine quoted Rantala as saying.
In the second method, the user simply places a finger anywhere on the screen and holds it still. The phone then displays a character by vibrating the sequence of six dots, each 360 milliseconds apart.
‘It took some time for them to start reading, because this representation is totally different from anything else that they had previously used,’ said Rantala.
But once the volunteers were used to it, they could speed it up and read a character in as little as 1.25 seconds.
Now, the researchers are trying to present entire words and sentences.
Already screen-reading software is available, which ‘grabs’ information displayed as text and turns it into speech.
The same information could be turned into Braille characters on phones with vibrating touch screens, said Rantala.