Tactile display unit for blind people - has groups of projecting pegs forming Braille symbols

摘要

A tactile display panel for blind persons or persons with seriously impaired vision consists of a panel with groups of projecting pegs arranged to form Braille symbols. Each peg (2) fits in a hole in the panels (1) (18) and covers a hole (16) in a thin plate (17). This hole is also covered on the underside by a piston (13) attached to a wire (14) made of memory metal. A duct (10) supplied with compressed air is formed immediately below the thin plate (17). When the memory wire (14) is heated by passing an electric current through it, it contracts and pulls the piston (13) away from the hole (16) in the thin plate (17). Compressed air then flows through the hole (16) and lifts the peg (2) so that its tip projects above the surface of the panel.