ELearning for Persons with Visual Disabilities: Case of Low Vision

ELearning for Persons with Visual Disabilities: Case of Low Vision

Ruth N. Wambua (The University of Nairobi, Kenya) and Robert Oboko (The University of Nairobi, Kenya)
DOI: 10.4018/978-1-4666-8363-1.ch012
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This chapter discusses an eLearning platform that is usable by persons with low vision. To start with, such a platform is achieved by incorporating technological advances such as: use of text with the highest possible contrast; use of varying font size; among other customized Human Computer Interaction (HCI) effects. Moreover, use of complicated, decorative or cursive fonts should be avoided, as well as italic text and capital letters, which can be difficult for users with reading impairments. In summary, this chapter supports the fact that eLearning is possible for persons with low vision, provided that all the necessary technological advances have been considered.
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Persons of low vision refer to people who have sight problems, in that they have partial sight. Consequently such individuals experience difficulties in reading/studying either from a book print or computer screen. For some individuals, the standard size of letters on a computer screen or printed in documents are too small to read, whereas others may not distinguish one color from another. The reason for low vision according to Bjork, Ottosson & Thorsteinsdottir (2008) could be because of clouding of the lens of the eye, which causes light that passes through the lens to the retina to be scattered. The scattered light causes images to be blurred and visual acuity to be reduced. Moreover, as one continues to age, the lens of the eye also yellows and becomes fixed and is thus unable to focus. In this case, the pupil does not dilate very well to changes in illumination, and the retina and cortex become less able to process visual information. Consequently, contrast sensitivity decreases, visual acuity drops somewhat, and vision in low light levels suffers. On the contrary, low vision is also suffered by the young in schools and colleges.

Following the remarkable advances in technology, there is dire need for support technology which goes a long way to ensure that individuals with partial sight impairment also benefit from technological advances such as eLearning. Considering that people with low vision are still capable of using the normal standard computer keyboards and screen, improved technological advancements would ensure that they are also able to type using those keyboards and read from those screens. For example, according to Burgstahler (2012), computer-generated symbols, both text and graphics, can be enlarged on the monitor or printer, thereby allowing individuals with low vision to use standard word processing, spreadsheet, electronic mail, and other software applications. Moreover, the ability to adjust the color of the monitor or change the foreground and background colors is also of value.

This chapter discusses a technological eLearning platform for people with low vision. The level of visual impairment and blindness in this case is based on the World Health Organization document: International Statistical Classification of Diseases and Related Health Problems (World Health Organization, 2010). The details are as tabulated in Table 1: Level of visual impairment and blindness according to the world health organization

Table 1.
Level of visual impairment and blindness according to the World Health Organization
Level of BlindnessDefinitionImplications
0Mild or no Visual ImpairmentVision better than:
6/18, 3/10, 20/70
May be glasses
1Moderate Visual ImpairmentVision better than:
6/60, 1/10, 20/200
Vision worse than:
6/18, 3/10, 20/70
Glasses and possible need for magnifiers on computer interface
2Severe Visual ImpairmentVision better than:
3/60, 1/20, 20/400
Vision worse than:
6/60, 1/10, 20/200
Magnifiers and color contrasters for computer interfaces
3BlindnessVision better than:
Can count fingers @ at 1 meter distance
Vision worse than:
3/60, 1/20, 20/400
Strong magnifiers for some but mainly screen readers for computer interfaces
4BlindnessVision better than:
Light perception
Vision worse than:
1/60, 1/50, 5/300
Screen readers for computer interfaces
5BlindnessNo light perceptionScreen readers for computer interfaces

Key Terms in this Chapter

Apache: is the most popular of all the web servers available because it supplies basic web server functionalities.

PWLV: Persons With Low Vision.

FOSS: Free and open source software.

PWLV: Persons with Low Vision refer to people who have sight problems, in that they have partial sight.

eLearning: refers to leaning electronically. In this case, being able to acquire knowledge through reading and studying from materials that have been made accessible through a machine/computer.

PHP: is the web development language written by and for web developers. PHP stands for Hypertext Preprocessor. It is a robust, server-side, open source scripting language that is extremely flexible and very easy to learn.

HCI: Human Computer Interface.

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