Scientists have developed a new touchscreen tablet to help visually impaired people find their way around unfamiliar places using their fingers.
The device quickly forms shapes and relief maps that users can then explore with their fingers, using their sense of touch.
The tablet could also be used to help visually impaired students learn subjects such as geometry or mathematics.
Navigating in an unfamiliar setting is a major challenge for people with a visual impairment.
To make it easier for them to find their way, researchers at Ecole Polytechnique Federale de Lausanne (EPFL) in Switzerland have developed a lightweight and reconfigurable touchscreen tablet capable of generating shapes and maps.
Users can then "read" the graphic data on the screen with their fingers.
Measuring 12 by 15 centimetres, the tablet comprises 192 tiny buttons that can move up and down in just a few milliseconds, almost instantaneously creating patterns such as the layout of a building, street or conference room.
Users can also zoom in on a specific part of the map. The actuators are fast enough to make individual buttons vibrate.
The technology has already been tested by several visually impaired people.
Each button contains a tiny magnet placed between two coils and two thin layers of steel.
Any given button can be moved up or down by generating a local magnetic field by driving current through one of the coils for five milliseconds.
The magnetised buttons then remain in the up or down position because they attach to one the two steel plates.
"The system requires no power to keep the button in place. This keeps energy consumption to a minimum," said Herbert Shea, director of EPFL's Microsystems for Space Technologies Laboratory.
The tablet also comes equipped with Bluetooth, so it can connect to computers and tablet PCs.
"People can read with a Braille display, and detect nearby obstacles with a white cane. Our tablet, which will not cost much to produce, will provide graphic information in real time, so the user can check out the layout of a room or street before venturing into it," said Shea.
In addition to helping guide people around, the tablet could also be used to help visually impaired schoolchildren.
"In geometry class, the tablet could be connected to the board to instantly reproduce all the shapes and graphics drawn by the teacher," said Shea.
