VISUAL IMPAIRMENTS


General information on Vision Disabilities and adaptive technology.

According to a survey by the National Center for Health Statistics, 1.4 million Americans have a severe visual impairment (defined as being unable to read ordinary newsprint); half of this group is registered as legally blind. Many of these individuals benefit from using computers, but still more could be helped.

The IBM PS/2 and PC families of computers are valuable tools with uses in many different environments - education, business, recreation and daily living tasks. With continuing technological improvements in the microcomputer industry, the number of current and potential users is rapidly increasing to include people who are visually impaired. Special adaptive hardware and software makes it possible.

HOW COMPUTERS HELP PERSONS WHO HAVE VISUAL IMPAIRMENTS

For persons with low vision, reading a standard computer screen or printed page usually presents an obstacle. The following adaptations for enlarged output (magnification) may help: magnification lenses for standard displays; larger characters on standard displays; alternative displays with better or different resolution and color; display devices or projectors; and for printed output, larger characters and more readable fonts.

Audio output or computerized voice let’s a blind user read by hearing the information on the computer screen. Screen reading software with speech synthesizer devices help the user navigate the screen to hear what others see.

Braille is an output alternative for people who are blind. Two types of Braille devices are Braille printers that produce embossed paper output and paperless tactile displays that use retractable pins to form Braille characters. Software programs perform the necessary translations to Braille files used by the Braille devices.

Input adaptations are also used by the visually impaired to improve accuracy and efficiency during data entry. The most frequently used device is the keyboard. Modifications include home key indicators (dimples/dots or felt appliqués) and key replacement (larger, more unique) for the often-used keys. Also, the speech synthesizer allows audio output during data entry - providing immediate feedback as the user unable to verify visually enters data.

Another technology with significant advancements in price/performance is optical reader and character recognition software. Printed information is presented through the combination of scanned character recognition to obtain the information in a computer form (machine-readable) with alternate output (Braille or synthetic speech) to read the data. There are many products for the IBM PS/2 that address productivity and usability for all users. A helpful tool for people with vision impairments is the modem - and the software that allows, through telephone lines, the exchange of machine-readable information, to access data banks of information and electronic bulletin boards.

Other uses for telecommunication technology are found in daily living activities. Computerized directory look-up and dialing simplify telephone usage: and mailing, banking and shopping may be done at home.

Helpful products for keyboard entry include: abbreviation expansion/keyboard macros, spelling checkers and online thesauruses. Online machine-readable product documentation is preferred to printed material. Products developed specifically for this special population is: --- Word processors with synthesized speech output designed into the product's operation.

--- File readers to provide general-purpose voice output of machine-readable files (other audio output aids.

--- Information handlers such as talking phone directories, talking calculators and general file management products (other audio output aids).

--- Alternative to printed documentation of hardware and software manuals, e.g., audiocassette, Braille or machine-readable formats.


In summary, technology and support are available for many blind and visually impaired individuals. The challenge remains to increase the awareness of the benefits that computer technology affords to all who might use it.

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