Neues Patent zur Erzeugung von Computerbraille

[abraxas_bEi_mail2.isys.net (Michael Lang)]

Das folgende ist der Abschnitt eines Artikels, der am Montag in der
New York Times erschien. Braillezeilen sind extrem teuer. In diesem
Text geht's um ein Patent, das die Firma Texas Instruments bekommen
hat. Dort wurde eine Methode entwickelt, Braille zu erzeugen. Diese
nutzt hauptsaechlich chemische Vorgaenge im Gegensatz zu unseren
Braillezeilen, in denen sich ja viel anfaellige und teure Mechanik
befindet. Die Frage ist, ob diese neue Methode tatsaechlich geeigneter
ist als die alte Piezotechnik. Mich erinnert der Text an das
Fluessigkeitstableau, das von der Uni Hagen entwickelt wurde, von
dem ich aber lange nichts mehr gehoert habe.
 
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      April 7, 1997
 
Patents: Creating Braille Electronically; Glow-In-The-Dark Bubbles
 
      By SABRA CHARTRAND
 
     H undreds of thousands of blind Americans read by using Braille. In
     1990, 4.3 million people had severe vision loss, and 512,000 of
     those were blind in both eyes.
 
     But that does not mean they can read easily. Fluency in Louis
     Braille's 1825 system can be difficult without a lot of practice.
     Mastering the system of one to six embossed dots arranged in two
     columns of three dots each to represent letters and words requires
     diligent repetition. A similar system of eight dots in two columns
     of four each is used for mathematical symbols and to represent
     ASCII, the generic computer code.
 
     But many blind people cannot spend as much time reading Braille as
     they might like because the "cost of Braille means it's not even
     affordable to most sight-impaired people," said Marvin Cowens, a
     polymer chemist at Texas Instruments Inc. Together with Alan Gilkes
     and Larry Taylor, Cowens has won a patent for a display that
     creates renewable, raised dots on computer monitors and other
     screens.
 
     Braille books and other printed materials are expensive to produce
     and own. The printing process is costly, the bulky books require
     extra storage space and the dots can begin to deteriorate after
     only a few readings. Braille systems for display screens exist,
     Cowens said, but they are complex machines that can cost $5,000 to
     $10,000 each.
 
     "They're a mechanical nightmare to me," he said. Cowens, whose
     sight is normal, is trying now to learn Braille using the current
     technology. "They rely on mechanical pegs that stick up and have a
     lot of moving parts."
 
     In addition to being expensive, the mechanical system also displays
     only one line of text per screen, making it cumbersome for Braille
     readers to scan a page or search for information in a document.
 
     Yet the American Federation for the Blind says 85 percent of people
     who use Braille as their primary method of reading and are Braille
     literate have jobs. So Braille fluency can make a big difference in
     the life of a blind or visually impaired person.
 
     The Texas Instruments invention "consists of a matrix of small
     cavities, each containing a positive and negative electrode, and
     filled with a small quantity of polar organic gel responsive to
     electric fields," the patent explains. A taut film is spread over
     the matrix to seal the cavities and keeps each one flat.
 
     "Each cavity is individually addressable by electronic means," the
     patent continues. "When voltage is applied to the electrodes in a
     cavity, the gel in that cavity expands sufficiently to raise a
     dimple in the elastomeric film."
 
     The cavities are cylindrical in shape, with metal electrodes
     embedded on the floor and one side. They create dots in the
     standard Braille size of 1.5 millimeter, but can be adjusted to
     other sizes -- such as larger dots for those with less sensitive
     fingertips. The circuitry that delivers electricity to the gel can
     also cause the dots to vibrate, so letters or words can be
     "highlighted." The computer can also register when dots have been
     touched, so it will know when a word has been read or when to turn
     a page. Users might also be able to design and customize their own
     Braille systems.
 
     The company says the displays can make word-processing, spread
     sheets, graphs, CD-ROM materials, e-mail and online data bases
     accessible to Braille readers. Books and other paper documents
     could be scanned into a computer equipped with the Braille display.
     The screen can run Braille in English or other languages. Special
     software programs will command the computer to convey Braille dot
     instructions, rather than the alphabet, to the screen.
 
     Texas Instruments believes its system will help organizations,
     buildings and device manufacturers comply with the Americans With
     Disabilities Act. But it may be a while before the company has a
     product to offer.
 
     "We aren't selling anything yet," Cowens said of the invention. He
     also did not want to guess what a Braille personal computer or
     laptop display would cost consumers, other than to say it would be
     "substantially less" than current systems.
 
     "We have proved the feasibility of the system, but there's still a
     lot of work to be done, he said. "We're still in the laboratory."
 
     Cowens, Gilkes and Taylor received patent 5,580,251.