Blind card

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An information board made of white, marble-like material is mounted on a wooden plate. In its center it shows the U-shaped plan of a salt works as a tactile and visible relief. All around the representation of the floor plan there are lettering in raised normal font and in Braille.
Map for the blind of the Royal Saltworks in Arc-et-Senans (France)
The black and white photo from 1986 shows an information board placed vertically. Under the heading "BLIND PARK of the City of Leipzig", the largest part of the board shows a drawn plan of the park with a large meadow, paths and wooded areas. In the right fifth of the panel, several black reliefs are arranged vertically one below the other, which evidently represent excerpts of the plan. On the right edge of the picture stands a woman who is touching the top of these reliefs with her fingertips.
Park for the blind in Leipzig, information board

Blind map ( tactile map ) are for blind palpable geographical and severely visually impaired people cards , and city and mountain models. For finger scanning, the map objects are shown raised and usually labeled with Braille . Since colored information cannot be used, maps for the blind use tactile textures .

The blind card is a special form of the blind graphic .

Past and present

In the past, individual copies of cards for the blind, e.g. B. for blind schools carved in wood or made of leather. Braille lettering was mostly dispensed with because the representation was not filigree enough.

Nowadays, transportable tactile cards are mostly produced for larger editions by making a positive from which a negative is created as a shape for machine deep drawing , with the Braille lettering can easily be used by a strip pen.

Due to the legal requirements for accessibility , tactile maps are enjoying increasing popularity, for example in train stations.

The unavailability for less touristically interesting places continues to be a major problem.

species

As with visual maps, different content can be represented. Common types are

  • Road map, scale approx. 1: 1000 to 1: 2000
  • Political map (municipalities, regions, countries, states)
  • Geographic maps (rivers, mostly with political borders)
  • City models, often made of bronze, with replicas of buildings
  • Mountain models, e.g. B. made of plastic
  • Globe with mountain relief

production method

The historical black and white photo from the beginning of the 20th century shows the interior of a very tidy workshop. In the foreground on the left a man is sitting on a wooden chair in front of a strange machine on which he is making a card for the blind. The man has turned his right side towards the viewer, the machine is on his right. The strikingly low chair has an old-fashioned wooden frame and a presumably swiveling seat with a backrest. The 40-year-old man is wearing a dark suit with a tie and polished leather shoes, and his hair is combed back. The machine is roughly waist-high and essentially consists of a frame with four curved legs (probably made of cast iron) that carry a stamping device at the top. The legs are drawn apart in a curve downwards, in the foot area of ​​the machine that is widened as a result, a pedal is attached - similar to that on an old sewing machine. The man has put one foot on the pedal, a linkage leads upwards. At the upper end of the frame, at eye level with the person sitting in front of it, a sturdy metal bracket protruding to the right with a storage table underneath carries an embossing device. The man has pushed an A4-sized relief map onto the table and is watching intently how the embossing tools process the map.
Historical production of cards for the blind
  • Bronze casting
  • "Tinkering" the surfaces and Braille labeling of a single piece
  • "Tinkering" the surfaces and Braille labeling of a positive, then deep-drawing process
  • Creation of a virtual model on the computer using CAD , then production in a CNC- capable machine such as B. Milling machine, laser milling machine, 3D printer.
  • Print or drawing on swell paper , then exposure.
  • Creation of a virtual 2D model on the computer, then embossing of Braille and dotted or dashed paths and areas in a machine embossing on Braille paper (method according to Daniel Hänßgen)

Web links

Commons : Tactile Graphics  - collection of images, videos and audio files
Commons : City Maps and Models  - Collection of images, videos and audio files