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Currency Notes for Visually Impaired A Literature Review

Dr. Subir Das, Senior Ergonomist, Inter Disciplinary Design Studies and

Pallavi Kulkarni, Final Year Student, New Media Design

INTRODUCTION Money is an item or commodity accepted by people for exchange of goods, services or resources. Over the years, people have used a wide variety of items for money, such as seashells, beads, tea, fish hooks, fur, cattle and even tobacco. The first true paper money originated in China in about seventh century A.D. The idea was conceived by Chang Yung in the country of Chuh (Morgan, 1969). In India paper money (currency notes) was introduce by the English Traders towards the later part of the 18th century (Gupta, 2000). For convenient and confidential exchange of money in every day transaction, it is essential to identify and denominate currency notes without any difficulties by all sorts of people in all possible range of circumstances (National Research Council, 1995). But most of the time, banknotes provide no basis for denominating by people who are blind and have limited vision. A blind person has to trust others to inform them about denominations of the notes received. Usually blind people used a number of innovative methods for identification and denomination of currency notes which are not always fruitful. Blind and Visually Impaired People Recent study by WHO (2002) showed that at present globally there are more than 161 million visually impaired people, of whom 124 million people have low vision and 37 million are blind. Visual impairment is not distributed uniformly throughout the world. More than 90% of the worlds visually impaired live in developing countries. There are almost 13 million people in India who are visually disabled. The leading causes of low vision and blindness are diseases that are common in old age: age-related maculopathy, cataract, glaucoma, diabetic retinopathy, and optic nerve atrophy. Survey showed that more than two-thirds of all people with low vision are 65 years of age or older (Nelson and Dimitrova, 1993) and more than 25 percent of all people over 85 years of age are visually disabled (Genensky, 1994). Visual Impairment and Currency Notes During the last several decades, a number of countries are carrying out research on the development and incorporation of suitable features so that visually impaired people can identify and denominate currency notes independently and confidently, with the same ease and confidence like the sighted people. Out of 180 countries in the world that issue their own banknotes, around 50 countries print the banknotes internally; the remainders have their banknotes printed by commercial currency security printers under contract (National Research Council, 1995). A survey was conducted by the European Blind Union (EBU, 1994), German Federation of Blind and Visually Impaired People (DBSV) and the blind organisations of Belgium and Spain. The study revealed that special training is urgently needed to improve the ability of blind and partially sighted people to discriminate between the Euro coins and notes with ease. Regarding bank notes discriminating between the 20 and 50 Euro as well as between the 100 and 200 Euro presented the greatest difficulties for blind and partially sighted people. The mistakes blind and partially sighted people made during the trials were serious and would have entailed substantial disadvantages in real life situations. The ability to discriminate usually varied by country, age and type of visual impairment.

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CURRENCY IDENTIFICATION FEATURES Tactile features Humans perceive objects and the immediate environment through multiple sensory channels. People who are visually impaired possess a very keen sense of touch and hearing. As a receiving instrument the skin combines important aspects of the eye and the ear, with high acuity in both space and time (Gunther, 2001) giving it good potential as a communication medium. The skin can therefore potentially be used as a medium to communicate information. One common form of tactile output is Braille. Research has developed tactile graphics for blind people (this mainly takes the form of raised lines and dots on special swell paper). Kurze (1998) and Challis (2001) have developed guidelines which allow images and objects to be presented that are understandable through touch by blind users. Tactile displays are now becoming available in a form that can be easily used in a user interface. Tactons, or tactile icons, are structured, abstract messages that can be used to communicate information non-visually (Brewster and Brown, 2004).

Tactile features of the currency notes needs to be explorated with hands and fingers. For identifying these tactile features we need sensory inputs from two different sources i) citaneous sense from touch receptors on the skin, and ii) kinesthetic sense from positional receptors in the muscles and joints of hands and fingers. Durlach et al. (1989) performed a detailed study of tactile length discrimination and identification using judgments of distance between the thumb and forefinger.

There are two types of tactile features - i) one that may be incorporated into the currency notes during manufacture and ii) other one that involve modification of the currency notes after manufacture. A number of countries have used different types of tactile features either printed or embossed on their banknotes with limited success (Koeze, 1990; Cruz V., 1994). Features like tactile watermark and tactile threads could be incorporated during sheet manufacture to provide local thickness, which could be detected by touch as is used in Japanese currency (Minoshima, 1994). As long as the currency notes are new and crisp, the printed tactile marks are easily detectable (Koeze, 1990), but tactile features usually degrade with wear. The tactile watermark is less prone to this type of degradation than printed or embossed features. Sheet roughness could be changed during manufacture but study showed that it does not create enough tactile sensation to allow denomination of notes. Moreover, the intaglio printing process could flatten or smooth out the irregularities, as was observed during the development of the Japanese watermark (Minoshima, 1994). In Indian currency notes, a special feature in intaglio (different shapes for various denominations - Rs. 20 vertical rectangle, Rs.50 square, Rs.100 triangle, Rs.500 circle, Rs.1000 diamond), has been introduced to help the visually impaired to identify the denomination. But most of the visually impaired are not aware of this feature on the currency notes. Besides, portrait of Mahatma Gandhi, Reserve Bank seal, guarantee and promise clause, Ashoka Pillar Emblem on the left and RBI Governor's signature are also printed in intaglio (in raised prints), which can be felt by touch. More research is required on the effect of raised or tactile features on the ability to manufacture, stack, and sort banknotes at high speed and to determine what sorts of tactile features would minimize all these problems. Size: In more than 120 countries in the world, different-sized currency notes are used to indicate different denominations. Usually either length or height or sometimes both dimensions are utilized to differentiate between denominations and higher denominations always have larger size. In Europe, this feature was recommended by the Royal National Institute of the Blind and

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the European Blind Union (EBU, 1994; Jarvis, 1994). Research carried out by the Central Bank of Switzerland (BEP, 1983) also revealed the usefulness of size-denominated banknotes for blind people. To give orientation information, an additional feature would be necessary as is proved by effectiveness of the tactile marks used on Dutch currency (Koeze, 1990). In 2005, the Netherlands Federation of the Blind and Partially Sighted asked DNB (De Nederlandsche Bank) to incorporate better tactile features on the notes and a greater difference in length between the notes they use daily mainly the euro 10 and 20 denominations ( Hans, 2006). The European Blind Union recommends a minimum difference of 5 mm between denominations (EBU, 1994). Legge in 1994 carried out some preliminary experiments on size variation in length only. In six banknotes, when the differences between denominations were 6 mm, the identification accuracy was 50 percent. But when the differences between the denominations were 12 mm, identification accuracy improved to 75 percent. In another study (Brabyn, 1994) on four currency notes, when both length and height are varied by 7 mm and 5 mm, respectively a 90 percent success rate for identification is acheved in a very short learning time of one and half hour only. This proves that both length and height could be though of for better identification of different denominations. Bureau of Engraving and Printing (BEP, 1983) studied dimensions of currency notes of 38 countries. Results showed that in 36 countries, dimensional changes are there both in length and height, whereas, banknotes of Israel and Netherlands varied in length only. In most of the cases, dimensional changes are not linear through the series of banknote denominations.

The visually impaired often try to identify the denomination by measuring the currency note with their hand. Can giving tactile treatment to the currency be an alternative? Edge Modification: Providing notches, cut corners or modification of edges are the other possibilities to indicate denominations. Initially, clipping of corners was considered by a number of countries but is not currently in use. There are possibility of confusion with cut corners by both people and machines. Moreover, sharp notch may have a tendency to enhance delimitation or tearing. But different edge patterns, in addition to helping with denomination, could also provide information on the orientation of the note for visually impaired (National Research Council, 1995). Holes: Holes into the currency note could be another useful feature for both orientation and denomination. Oschwald and Hendricks (1994) suggested that If the holes are confined to the lower left quadrant of the front of the currency note for all denominations, it would be easy to orient the notes properly. Studies showed that depressed areas are more difficult to detect from a background than raised areas. Therefore, holes larger than braille dots would be required for accurate identification. But there is a need to study the impact of holes on banknote durability, the psychological matters regarding issuing and using banknotes containing holes and obviously, the impact of increasing the number of processing steps, wastage of material and the cost of drilling.

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Numerals: Visually disabled people more easily identify numerals, when they are large, high-contrast, usually greater than 40 percent of the full height of the currency notes and are placed on a simple, uniform background (National Research Council, 1995). Preferably there should be one large numeral on each side of the currency notes. Organizations supporting visually disabled people (EBU, 1994; Bennett, 1994) also recommended large numerals on a plain, uncluttered background to provide high contrast for readability. Though white numerals on black or black on white background are easy to identify, people with cataract often see better with white characters on a dark background whereas, in new Canadian $20 note, the numeral is dark on a light background (National Research Council, 1995). Color: Just a few days after the introduction of the euro notes, DNB (De Nederlandsche Bank) received complaint that colour blind citizens hardly see any difference between the colours of the euro 5 and 10 notes. Later on, DNB made their apologies to the Dutch colour-blind and promised to make amends in future euro banknote series (Hans, 2006).

Although people have various degrees of color vision, if each currency note value is assigned a predominant colour, it can serve as a dominant aid specifically for those persons with low vision who could not make out of numerals but are able to discriminate different colours. Canadian banknotes have a dominant colour which varied by denominations. EUR 10 banknote is red and the EUR 20 is blue. Even where countries use same-size banknotes for each denomination, they use a clearly differentiated color scheme for all denominations (National Research Council, 1995).

Shapes and Coarse Patterns: Geometric shapes and coarse patterns large and printed on a clear or uncluttered background, could also be used to denote denominations, as are currently in use on British currency (Jarvis, 1994). Some learning time is necessary to develop a logical connection between geometric shape and current note values.

DEVICES FOR VISUALLY IMPAIRED Simple size-guide template made with a fixed alignment corner and varying lengths may act as an educational aid to blind people. Oschwald and Hendricks (1994) demonstrated a device template that contains notches related to the different note values.

A number of electronic devices are also available for blind and partially sighted people not only to recognize and denominate but also to authenticate currency notes. The quality of its performance depends mainly on the quality of the currency note inserted. But most of these devices cost between $300 and $400, which puts them out of reach for a large number of blind people (Brunson, 2003). Canada is currently promoting the use of a device, in recognizing different denominations, to assist almost 8,000 blind Canadians who cannot benefit from the large numerals and colors on the Canadian banknotes.

For ease of identification, currency notes should also be provided with some machine-readable features. England and Italy have incorporated techniques of using magnetic thread in bank notes that contained a coding unique to each denomination. A group of researchers are trying to incorporate fluorescent, magnetic, or infrared reactive inks to be incorporated in a simple bar code arrangement to allow for basic machine interrogation. These types of codes are used on Scottish banknotes and Eastern Caribbean Central Bank currency. Similarly, magnetic bar coding is used on the newer series of U.S. dollar bills and could be used as the basis for device design (National Research Council, 1995).

CONCLUSION Currency notes should always be accessible to people who are blind and visually impaired. Based on long-term research and recommendations from blind peoples organizations, most of

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the countries have already incorporated multiple features like tactile marks, large numerals, colour coding, etc. to increase the number of denominational cues. But what is lacking is the proper training programme for the blind and visually impaired. There is also a need to develop smaller, faster and low-cost denomination devices to denominate and at the same time authenticate the currency notes. REFERENCES 1. Morgan, E. V. (1969): A history of money, Penguin Books, U.K., P. 240. 2. Gupta, P. L. (2000): Paper money of India, Currencies & Coins, Mumbai, P. 464. 3. National Research Council (1995): Currency features for visually impaired people, National

Adademy Press, New York. P. 144. 4. World Health Organization (WHO): Magnitude and causes of visual impairment, 2002. 5. Nelson, K. A., and Dimitrova, E. (1993): Severe visual impairment in the United States and in each

state, 1990. Journal Visual Impairment and Blindness, 87(3):80-85. 6. Genensky, S. (1994): Personal communication to the Committee on Currency Features Usable by the

Visually Impaired, March 30, 1994. 7. European Blind Union (1994): A Report of the European Blind Union Expert Working Group on

Currency: Recommendations for the Design of the ECU. Paris, France: EBU. 8. Gunther, E. (2001): Skinscape: A Tool for Composition in the Tactile Modality. Massachusetts

Institute of Technology. Masters of Engineering. 9. Kurze, M. (1998): TGuide: a guidance system for tactile image exploration. Proceedings of ACM

ASSETS '98, Marina del Rey, CA, ACM Press. 10. Challis, B. and Edwards, A. D. N. (2001): Design principles for tactile interaction. In Haptic Human-

Computer Interaction, Vol. 2058 (Eds, Brewster, S. A. and Murray-Smith, R.) Springer LNCS, Berlin, Germany, pp. 17-24.

11. Brewster, S. and Brown, L. M. (2004): Tactons: structured tactile messages for non-visual information display, Proceedings of the 5th Australasian User Interface Conference (AUIC2004), Dunedin, in Conferences in Research and Practice in Information Technology, Vol. 28. A. Cockburn, Ed.

12. Durlach N., Delhorne, L., Wong, A., Ko, W., Rabinowitz, W. and Hollerback, J. (1989): Manual discrimination and identification of length by the finger-span method. Perception and Psychophysics, 46:29-38.

13. Koeze, P. (1990): A Large-Scale Experiment on the Effectiveness of the Marks for the Blindon Netherlands Banknotes. Presented at the European Banknote Printers' Conference, Rome.

14. Cruz V., R. (1994): Personal communication to the Committee on Currency Features Usable by the Visually Impaired, June 1994.

15. Minoshima, Y. (1994): Personal communication to the Committee on Currency Features Usable by the Visually Impaired, May 1994.

16. Jarvis, A. (1994): Personal communication to the Committee on Currency Features Usable by the Visually Impaired, May 1994.

17. Bureau of Engraving and Printing (1983): A Study of Mechanisms for the Denomination of U.S. Currency by the Blind or Visually Impaired. Bureau of Engraving and Printing report to Congressman Edward R. Roybal, Chairman of the Select Committee on Aging, U.S. House of Representatives.

18. Hans A. M. de Heij (2006): Public feed back for better banknote design, De Nederlandsche Bank NV, Amsterdam, The Netherlands, Proceedings of SPIE Vol. 6075, P. 41.

19. Legge, G. E. (1994): Personal communication to the Committee on Currency Features Usable by the Visually Impaired, August 16, 1994.

20. Brabyn, J. A. (1994): Personal communication to the Committee on Currency Features Usable by the Visually Impaired, August 16, 1994.

21. Oschwald, J. and C. Hendricks. (1994): Presentation to the Committee on Currency Features Usable by the Visually Impaired, March 30, 1994.

22. Bennett, D.G.M. (1994): Personal communication to the Committee on Currency Features Usable by the Visually Impaired, May 1994.

23. Brunson, M. (2003): Show me the money making currency accessible to people who are blind, Information Technology and Disabilities, Vol. IX No. 1 October, 2003, Director of Advocacy and Governmental Affairs, American Council of the Blind.