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Web Posted on: August 24, 1998

Economic Aspects of Flexible Braille Production Using Present-day Electronics, Mechanics and Software.

Guido François

Dept. Elektrotechniek - T.E.O., Kardinaal Mercierlaan 94, B-3001 Heverlee, Belgium
tel: +32 16 32 11 21, fax: +32 16 32 19 86, email: guido.francois@esat.kuleuven.ac.be


1. Braille as an instrument for communication.

For many years, people have been searching for techniques that would give the blind and the visually handicapped an autonomous way of written communication. Clearly, tactile reading could replace visual reading and attempts were made accordingly, using either regular or stylised characters printed in relief. Early in the 19 th century, a commander of the French artillery by the name of Charles Barbier de la Serre wanted to use patterns of dots on paper to allow his troops to communicate in the dark. In order to have his technique tested by subjects that would not - or rather could not - cheat, he went to the school of Valentin Haüy for the blind in Paris. The potential of dot writing was immediately recognised by the students, one of which was Louis Braille who further developed the technique of representing characters by six dots in a 2x3 matrix and gave it his name. It became and it still is a worldwide success.

We may wonder what the basis is for this generalised preference for a writing technique that is highly abstract. In fact, so abstract that it can be used for all languages and all character systems of the world. I believe, there are 3 good reasons:

  1. The 6-dot Braille writing is well-adapted to the sensitivity of the fingertip.
  2. The dot is the simplest form of relief and as such is well supported by a universal low-cost carrier which is paper.
  3. The slate and stylus needed for autonomous Braille writing by hand are very simple lightweight tools.

Braille writing has been challenged by audio cassettes and - more recently - by synthetic speech. This challenge is not a real one: without writing - and writing almost exclusively means Braille - the blind would be condemned to illiteracy. The new techniques will supplement Braille, not replace it. The same is true for so-called paperless Braille: temporary display of Braille on a mechanical device. Such devices are expensive and delicate but most important, their display is limited to one reading line. Even people that use them all-day long on a professional basis, prefer Braille on paper for normal reading.

Concluding, we can consider Braille writing as one of the great achievements of humanity. An asset that we mastered and that we will enjoy for as long as we are here until maybe some day, blindness itself can be eliminated.

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2. Techniques for printing Braille

As far as writing and reading goes, Braille is an excellent match for inkprint. But what about printing?

2.1 Classical techniques

In the more than one - and - one - half centuries since Louis Braille’s invention and before the generalised breakthrough of the information technology, mainly two techniques have been developed for Braille production: the Braille typewriter and the Braille press. Both are still widely used today. The typewriter delivers single copies and, if necessary, these can be duplicated on thermoplastic sheets. Braille presses deliver multiple copies from masters made out of zinc, aluminum or hard plastic. These copies must be collated into books. The making and the storage of the masters represent an investment that only pays off if a sufficiently large number of copies is needed. With press technology, double-sided printing is possible: the dots on one side of the paper are arranged to match the spaces between the dots on the other side. This technique is called interpoint printing.

2.2 Techniques using Information Technology

Microprocessors and Personal Computers have given us easy and widespread access to electronic information storage and retrieval. The zinc masters need no longer be typed by hand: an automatic puncher makes them 3 to 5 times faster. The typewriter too has been mechanised: PC driven, some models will print more than 50 characters/sec. Originally built as a reinforced matrix printer, they have come to a technology of their own, and are capable of interpoint printing.

The most interesting development is the line printer. This device prints rows of dots over the full width - or length - of a page with outputs ranging from 100 up to 800 characters per second. The latter is equivalent to more than 2000 pages A4 of Braille per hour. That is still a factor of 2 to 5 lower than an automatic press, but both the fabrication of the matrix and the collating are eliminated. For printing volumes up to over 100 copies, the line printer beats the press in time.

The PC can do more than just drive the printer: it will take care of the text processing that precedes the printing. It can also be programmed to apply the rules of Braille writing. Some of these rules can be rather complicated especially for those languages in which contractions have been developed in order to speed up Braille reading and to reduce the volume of Braille documents. Excellent software is now available to perform these tasks. This means that, starting from the files of an editor, any book could in principle be issued in Braille, almost automatically. If the files are not available, then optical scanning of an inkprint copy can do the job. Some caution here is appropriate: Braille is rather intolerant of typing errors. The process of scanning even when backed by a dictionary, is likely to give too high an error rate. In addition, a high quality Braille issue has its own layout requirements that may be difficult to implement in the text processing. And if it comes to books for the school, the modern graphical inkprint layout is totally inappropriate for a Braille edition so that manual re-editing seems to be unavoidable. The solution here must come from advanced tagging techniques that can tell the text processor how to handle specific parts of the documents. Projects to develop such techniques are well on their way and the European Community has been a driving force in this matter.

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3. Cost evaluation

Braille printing has the reputation of being expensive. We believe that this is a heritage of the past rather than a reality. To be precise: this statement no longer holds and I will try to prove it by calculating the printing cost for a medium-size book of 500 000 characters.

In order to make a Braille edition of a book or a document, we need to go through the following steps:

  • The input of the source text
  • The processing of the text into Braille
  • The proofreading and correction
  • The embossing
  • The collating and binding.

In doing so, we will need operator time, equipment and consumables. I will not consider overhead costs.

The equipment is a decisive element for the total cost because it will determine the cost of the other elements as well. I therefore suppose that we use modern PC’s with appropriate software and an advanced line printer, of the type that we have been developing for a number of years. The investment for this equipment will range from 60 000 to 75 000 Euro, depending on the kind of binding that will be used.

The cost of text input is to be figured as operator time. Until a decade ago, this cost was rather high, because in practice all text had to be retyped: computers were insufficiently compatible and software was unable to transform text into Braille in a satisfactory manner. Today, editor’s files can be used, and with standardized tagging, the text, no matter how complicated, should be transformed into high-quality Braille with no other operator action than supervision. The cost of inputting a 500 000 character document thus has come down from roughly one month’s operator time to a couple of days: a decrease with a factor of 10.

The cost of embossing will be that of the Braille paper plus the maintenance of the printer. Most brands of printers require listing paper with pin-feed and fan-fold. Such paper may be 1,5 or 2 times more expensive than regular loose sheet as used in a Braille press. Since 1981 we have pioneered the use of paper on rolls. The diameter of these rolls may range up to 100cm. This is the most economic form of paper and in top quality its cost will be 13 Euro per 1000 sheet DinA4. Only recently has this technique been adopted by one other manufacturer. Long-term experience furthermore tells us that the all-including maintenance cost on a sustained basis for our equipment is less than 25% of the cost of the paper consumed.

The operator that handles the printer usually cares for the binding and both operations are well matched to one another. Figuring the operator salary to be 20 Euro per hour (including taxes and social security), the total printing cost of our 500 000 character document in DinA4 size interpoint will be:
700 pages/ 350 sheets/ 4 Braille volumes/ 20 minutes of printing/ (0,7x13)(1,25) + (1/3 x 20) + 2 = 20 Euro. We have added 2 Euro for binding materials. The input cost of the text will amount to roughly 15 times as much but it can be spread over as many copies of the document as are being made. The capital cost of the investment, spread over 10 years with a modest rate of 1000 hours of operation per year, will add another 2,5 Euro only.

In summary, the marginal cost for a Braille copy of a medium-size book will be about 23 Euro and that includes all the elements of printing (40%) and binding (9%), the operator time (30%), the maintenance (10%) and amortisation (11%) of the equipment.

It is interesting to compare the above figures to similar ones for the classical equipment. Transcription of our book by Braille typewriter will cost about 400 Euro of operator time per copy. No wonder appeals were made in the past for people to volunteer their time. Today, this approach can no longer be justified in Western countries, where modern equipment is accessible. Transcription by a fast automatic press with computer-driven plate embossing and followed by automatic collating may still beat the line printer for large volume printing but due to high setup cost, break-even will not occur before 100 copies at least. In addition, the equipment investment is about 3 times higher and much more space is needed.

Cost and speed are not the only parameters: production flexibility may be just as important. Here the line printer scores high for it can make a single copy just as efficiently and economically as a batch of 100.

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4. Conclusion

Using present-day information technology and modern line printers, the Braille edition of a document can be made at the same time as the inkprint edition and the cost for this service can be kept under control. The following examples may confirm this: since 1992, one of the foremost newspapers in Belgium has a daily Braille edition. The subscribers pay the same price and get their morning newspaper in the mailbox at the same time as their sighted neighbour. A similar operation was started in Nancy (France) in 1990. In Etampes the EBREC association is making available in Braille all official documents of the French government, departments and cities. In the Netherlands, the Braille printing houses of Amsterdam, Ermelo, the Hague and Nijmegen all use line printers. The presses they used before have been set aside.

On a more general level, we can see the following trends:

  1. Braille presses are getting obsolete.
  2. New applications for Braille production are emerging.
  3. Braille libraries no longer stock and handle books. Rather they print books on demand.

As a conclusion, we can see a dream come true: that any book or document can be made available in Braille, without delay and at affordable cost, giving the blind and the visually handicapped more and better access to information and a better chance for integration in our society.

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