Persons with visual impairment have been known to experience functional loss of vision or visual incapability which cannot be rectified by refractive corrections, medications or surgery (Adetoro, 2009). Visually impaired persons experience eye disorders which include retina degeneration, albinism, cataracts, glaucoma, muscular problems that result in visual disturbances, cornea disorders, diabetic retinopathy, congenital disorders and infection (Arditi and Rosenthal, 1998). They contend with visual system defects which affect their individual ability to perform activities of daily living. These conditions include partial sightedness, low vision and total blindness.
The visually impaired rely on alternative formats such as Braille, large prints and talking book or audio recordings to meet their reading needs.
In Nigeria, the population of the visually impaired is estimated at 3 million (Atinmo, 2002). Very few of these have received formal education and are capable of reading or writing Braille. The majority resort to begging on the streets as a means of livelihood (Adetoro, 2009).