Learning With Computers
Glenn M. Kleiman
Aids For The Blind
Dr. Glenn M. Kleiman is an educational psychologist and software developer. He is the author of Brave New Schools: How Computers Can Change Education (Reston/Prentice-Hall) and the designer of Square Pairs, an educational game program (Scholastic, Inc.).
Computers provide new and powerful aids for blind people. With special input and output devices and programs, computers enable blind people to more effectively substitute hearing and touch for sight and to use books, magazines, and newspapers that would otherwise be inaccessible to them. Computers can help blind people enjoy new opportunities for education, employment, social interaction, and recreation.
Much of this information about aids for the blind has been provided by the staff of the Sensory Aids Foundation of Palo Alto, California. They train blind people in job skills and help them find suitable jobs. They receive support from some of the major computer and electronics companies in Silicon Valley, and have placed workers at these companies. Other information has been provided by Telesensory Systems, Inc., the developers of Optacon and VersaBraille.
Computer Speech Synthesis
Speech synthesizers and text-to-speech conversion programs make it possible for computers to pronounce any word. The speech is not perfect, but people understand it easily after they get accustomed to it. During a visit to the Sensory Aids Foundation, I watched a demonstration of a talking terminal—a computer terminal combined with a speech synthesizer.
The blind user of the talking terminal has a control that lets him move a pointer to any line on the display screen. He can have the computer announce what line the pointer is on and speak the words on that line. He can have it repeat any words or read letter by letter. He can use the keyboard to edit the line.
Talking terminals make almost all the capabilities of a computer accessible to blind people. At Sensory Aids, blind people learn to use talking terminals for data entry, information retrieval, word processing, and programming.
Many educational programs could be used by blind people if the computer spoke what appears on the display screen. Staff members at Sensory Aids are revising some popular programs so that blind people can use them. During my visit, I saw a version of MasterType that was adapted for the blind. In the MasterType program, letters and words "attack" a central station. The user defends the station by typing the letters and words before they reach the station. In the adapted version of this program, the computer says the letters and words to be typed, and announces whether they have been typed correctly and quickly enough to defend the station.
Large Print Displays
Many people with impaired vision cannot read normal print, but can read large, high-contrast print. There are several ways to create large letters on the computer screen with standard equipment. One is to simply use a television or video monitor with a large display screen. Another is to use the computer's graphics capability to create large letters. In addition, many computer printers can produce large type on paper. With a suitable printer, any information stored in the computer can be printed in large letters.
A special large-print display processor, manufactured by Visualtek, magnifies letters on personal computer screens up to 16 times their usual size. A control panel lets the user set the scanning rate at which the letters move across the display screen.
Many people cannot see any letters, no matter how large. But these people can read when the letters are converted to a tactile form. One device which does that, Optacon, is already used by many blind people.
Optacon consists of a small camera, an electronics unit, and a stimulator array. The array is composed of 144 miniature rods. The electronics unit interprets the light pattern received by the camera and sends signals that cause certain rods to vibrate, thereby producing a tactile analogue to the light pattern. Some training is necessary to learn to read the vibrating patterns, but once this is mastered the blind person has access to all printed materials. Special adapters are available so that Optacon can be used to read computer screens and calculator displays.
Other devices use Braille, a system of writing in which each letter is represented by a pattern of raised dots in a 2 × 3 grid. Blind people read by feeling the dot patterns.
Although widely used, Braille has several disadvantages. Braille books are extremely bulky: A standard student dictionary fills a three-foot-square box. Braille typewriters are noisy and slow. Errors in Braille type cannot be corrected, since the raised dots cannot be erased. Braille books are therefore expensive, and most books, newspapers, and magazines are never made available in Braille.
Braille Word Processing
Special Braille printers can be interfaced to computers so that any information in the computer can be transformed to Braille. This provides a remedy for the problem of Braille not being correctable. A word processing program can be used to produce a Braille text after all corrections have been made on the computer screen.
Other Braille output devices can be interfaced to computers. One example is a device that contains sets of pins arranged in the 2 × 3 Braille grid. Each pin can be raised or lowered, thereby providing a mechanical Braille display. This device can be controlled by computer programs to produce instant Braille for a blind computer user.
A special device called VersaBraille incorporates recent advances in computer technology. VersaBraille is composed of a mechanical Braille display, a cassette information storage component, and a specially designed Braille keyboard, all under the control of a built-in computer. Information can be entered from the keyboard, revised and corrected (editing capabilities are built-in), stored on cassette, and transformed to Braille whenever needed.
VersaBraille provides a solution to the bulkiness of Braille. It is a self-contained unit that is easy to carry and can store 400 pages of Braille on a standard cassette tape.
A major advantage of VersaBraille is that it can be linked to a computer via a standard serial interface. A blind person can connect VersaBraille to a computer and quickly transfer information from the computer to VersaBraille's cassette storage system. The VersaBraille can then be taken away from the computer and read where and when convenient. A VersaBraille user can also take notes during class lectures, write reports, or enter any other information. He or she can then connect VersaBraille to a computer, transfer the information to the computer's memory, and use the computer to print the information, store it, or send it to others via an electronic mail system.
Computerized Letter Recognition
Speech synthesizers and text-to-speech programs can convert any words stored in a computer to speech. Other devices can convert information stored in a computer to large letter displays or to Braille or other tactile signals. However, much of the information people need is in books, not computers. To fully use the capability of computers to convert text to speech, Braille, or large print, we need efficient ways of transferring text from books to computers.
Special cameras and pattern recognition programs have been used for some time to recognize specially designed letters and numbers, such as the account numbers on checks. The camera converts the pattern of each letter into a binary code. A computer is programmed to process the binary code and determine which letter it represents.
In the last few years, devices and programs have been developed which make it possible for computers to recognize most typewritten characters and to adjust automatically for different type styles and sizes. In the next few years, this technology is likely to be perfected and become more widely available. (Only very limited success can be expected with handwritten letters, due to the large variations found in even one person's handwriting.)
Letter-recognition devices can be combined with appropriate output devices to produce large size displays, speech or Braille. Letter-recognition devices can also be combined with Braille printers to expedite the production of Braille books.
Converting Print To Speech
One impressive example of technology which serves the visually handicapped is the Kurzweil Reading Machine that converts print to speech. This machine combines sophisticated pattern recognition, speech synthesis, and text-to-speech conversion capabilities. It lets blind users control how the material is read. They can set the speed of reading and adjust the tonality of the voice. They can stop the reading at any time, have the last few words or lines repeated, request the machine to spell out words or announce punctuation and capitalization, and mark certain words or phrases for later reference. This reading machine is currently a very expensive device. But as the technology advances and prices decrease, machines with these capabilities should become available to all blind people.
Technology For The Blind
Of 51 blind people who were assisted by the Sensory Aids Foundation during a one-year period, fifteen are now programmers, computer operators, or systems analysts. Other occupations include design engineer, word processor, medical transcriber, account clerk, attorney, cashier, clerk-typist, physicist, and college professor. Their employers include Apple, Hewlett-Packard, Pacific Telephone, Stanford Linear Accelerator, Department of Immigration, Internal Revenue Service, and other businesses, educational institutions, and government agencies.
Current technological aids include Optacon, VersaBraille, talking terminals, talking calculators, and closed circuit television systems that produce enlarged images of print on a television screen. These devices, and others now in development, can dramatically increase the opportunities available to blind people.
Kurzweil Computer Products, Inc.
33 Cambridge Parkway
Cambridge, MA 02142
Sensory Aids Foundation
399 Sherman Ave., Suite 12
Palo Alto, CA 94306
Telesensory Systems, Inc.
3408 Hillview Ave.
P.O. Box 10099
Palo Alto, CA 94303
1610 26th Street
Santa Monica, CA 90404