From hzo at gmx.de Tue Oct 18 17:24:57 2005 From: hzo at gmx.de (Hans Zoebelein) Date: Tue, 18 Oct 2005 19:24:57 +0200 (CEST) Subject: Fw: Pocket Braille for people on the move: zb051015 (fwd) Message-ID: ---------- Forwarded message ---------- Date: Sun, 16 Oct 2005 19:10:17 +0200 From: Ari To: Linux for blind general discussion Subject: Fw: Pocket Braille for people on the move: zb051015 ----- Original Message ----- From: "TNAUK" To: "TNAUK" Sent: Saturday, October 15, 2005 7:04 PM Subject: Pocket Braille for people on the move: zb051015 > Pocket Braille for people on the move > > The article below may be of general interest to TNAUK subscribers > - it is article number 35 of this week's New Scientist, ns051015. > > #35 Pocket Braille for people on the move > > Celeste Biever > > AT LAST, the world's first portable electronic Braille display. It > is small enough to fit in a pocket and can even be rolled up like > a newspaper. > > The display consists of a sheet of tiny plastic paddles that bend > in response to a voltage. It is designed to connect to a > cellphone or laptop, and could also replace the liquid crystal > screen of an ordinary PDA. > > Existing dynamic displays for blind people use an array of pins > that pop up when stimulated by piezoelectric actuators. But the > smallest versions are the size of a phone book and weigh about > 500 grams, mainly because of the rigid fibreglass board the > actuators are mounted on. 'It's moderately portable, but you > certainly can't put it in your pocket,' says Curtis Chang of the > National Federation for the Blind in Des Moines, Iowa. At $3800 > each, they are also too expensive for most people. 'I think the > new display is a great idea,' Chang says. > > It will almost certainly be cheaper. Created by Takao Someya and > his team at the University of Tokyo, the display is made entirely > of a flexible polymer and thin metal films. These layers can be > printed using low-cost deposition techniques, making a price tag > of as little as $100 a distinct possibility, says Someya. > > The 16-centimetre-square prototype is just 1 millimetre thick and > weighs 5 grams. A grid of organic transistors sits on a polymer > membrane, with 144 plastic paddles on top. The entire device is > coated with thin rubber. > > The paddles are made of a negatively charged polymer seeded with > positively charged lithium ions and sandwiched between two metal > electrodes (see Diagram). When a voltage is applied across the > electrodes, the lithium ions migrate to the negative electrode on > the lower side of the paddle. The result is a crowd of ions at > the bottom, which expands the polymer and makes it bend upwards. > On the tip of each paddle is a sphere under a millimetre across, > which rises when the paddle bends, causing a bump in the rubber > surface. When the current is switched off, the ions disperse back > into the polymer, the paddle straightens and the bump disappears. > > The paddles take just under a second to move up or down, which is > acceptable for reading a book or a short message, but not for > someone working, says Chang. To make them move faster the > transistors need to be made smaller, so the electrons have less > distance to travel between the transistors' on and off state. > This might be possible using nanofabrication techniques, says > Someya. > > Someya will present the device at the International Electron > Devices meeting in Washington DC in December. > > The devices could also go beyond Braille and recreate whole scenes > on their surface, allowing the blind to feel images as well as > words. 'The idea is to create an array of tiny pixels,' says > Yoseph Bar-Cohen, an expert in Electro-active polymers at NASA's > Jet Propulsion Laboratory in Pasadena, California. > > But he is concerned the force of the paddles in Someya's device > may be too weak. 'If a blind person cannot feel the movement of > the dots, the device will not be practical.' > > > ------------------------------------------------------------ > > TNAUK publications are automatically distributed from this e-mail address- > any messages, other than those to the Automated Subscriber > Selection Facility will be lost. To find out how to use this > facility, which enables you to change the publications you > receive, temporarily stop email distribution while you are on > holiday, order back numbers or a Project Gutenberg book, send an > e-mail to > tnauk at dircon.co.uk > with, in the Subject line: > help > > Information and advice may be obtained from: > TNAUK, National Recording Centre, Heathfield TN21 8DB. > Tel: 01435 866 102 > FAX: 01435 865 422 > E-Mail: info at Tnauk.org.uk > Web: http://www.tnauk.org.uk > BBS 08457 419 489 > Contact Reception to join TNAUK or to request a title, and for all other > queries, speak to Ian McGregor on 01435 869 306 > ianmac at tnauk.org.uk > > > zb051015.txt sent using the zb.tdl distribution list, > > >