Project Proposal - Minicom Display for Deafblind People

By Hugh Sasse <>


Deafblind people face enormous communication problems, but not all deafblind people are profoundly deaf and totally blind. This is a proposal for a system that would allow a deaf person's text phone to be adapted for use by someone with low vision, by provision of a suitable display.


Many people are familiar with Braille, and they see it produced by large organizations for their blind customers. According to the BBC's programme "In Touch" there are 19,000 Braille users in the UK. According to RNIB there are about 21,000 deafblind people in the UK. Given that many of the braille users are just blind it is clear that lots of deafblind people are not braille users.

A person may be described as deafblind if they have any sight loss combined with any hearing loss. There is therefore a range of communication methods open to these people: some can manage lipreading, some sign language (if is is confined to a small area), and some can manage to use the telephone if it is amplified or with an inductive coupler to a hearing aid. However, not all are so fortunate. This project aims to find a solution for those with some sight who cannot see well enough to use a text telephone (textphone, Minicom, TTY, TDD) which they would use for telephone access otherwise.

The telephone has now become an almost indispensable form of communication, and for those who cannot see enough to use print, and cannot use braille, it may be their only possible way of communicating over a distance. The inability to use the phone impacts on their employability. Often, what is needed is just a textphone with a large, clear clear display. The current textphones with fluorescent displays are bright and clear in comparison to LCD displays but the characters are only formed from segments, and for people with retinal damage, and thus patchy vision, this can be a problem. Using a maginifier over the minicom is cumbersome, so a better option is a large display that con be coupled to the minicom.

So what is being proposed is a display for a textphone which is:

Why is this project non-trivial

Ultratec, who make the minicom make a large print, fluorescent display. However they will not distribute it in the UK, because they say that BABT approval is too expensive for the market size. Given the number of people producing products for braille users I doubt this. So the aspects that make this project a challenge are:

Optimizing ease of BABT type approval
This will be things like how the data is extracted from the minicom to be fed to the display, considering the regulations. Apart from using the centronics port on the minicom, there could be acoustic, or inductive coupling, each of which is treated differently by BABT.
Optimising display readability
Characters need to have a high contrast, but not be glarey. They need to be as smooth a shape as possible. As text flows along the display, ghosting must be minimal. Choice of display colour may be important.
Conventional Design limitations
The system will be in domestic and business settings. People who are used to sign language, with its 3-D grammar and ability to express one concept on each hand at the same time, have difficulty with English. This means that instruction booklets should be minimal, so the product must be easy to set up.
However, the reward for this effort may be quite large. Ultratec text phones are used all over the world, and this display would probably be better than the one they sell, which is, as far as I can tell, just a larger version of the normal 20 character display on the minicom. This would mean that there could be worldwide sales of such a product to deafblind people. Of course, many Deaf people lose some of their sight with age as the rest of us do. So this may have a market wider than those who would normally count themselves as deafblind.

It seems that similar problems are being faced in Australia.

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Last Modified 15-MAR-96 by James Gallagher