A Guide to Visual Disabilities
“Millions of people in the United States and around the world are inflicted by some type of disability, whether it is a hearing loss, a visual impairment, mobility impairment, or a learning disability. Despite laws that have been passed that have improved the lifestyles of persons with disabilities, these people face difficult challenges in their everyday lives.
"Visual impairments are divided into two general categories: blindness and low vision. Individuals with blindness have absolutely no sight, or have so little that learning must take place through other senses. Only 10-15% of the visually impaired population is totally blind. People with low vision have severe impairments and need special accommodations, but are still able to learn through vision." (Office for Students with Disabilities)
For a person to be considered legally blind, he/she must have a "visual acuity of 20/200 or worse in the better eye with correction (glasses), or a visual field which subtends to an angle of not greater than 20 degrees. A person with low vision has a visual acuity above 20/200 but worse than 20/70 in their better eye with correction." (Visual Impairment)
Typically in a school setting a student is considered visually impaired if the student's learning is affected by their vision. Generally, the biggest challenge that visually impaired students face in school and in the outside world is the huge mass of printed materials. In a classroom, a visually impaired person can be hindered if they are unable to use standard print materials such as textbooks, handouts and tests. To accommodate these students’ special provisions must be made.
Although our country and the world as a whole have made tremendous strides in improving access to those with disabilities, there is still room for improvement. In the booming age of technology, access to computers, the Internet and other technologies is steadily improving for those with disabilities. If we all consider this audience in our teaching practices and in designing web pages, access will improve that much more.
Adapted 2/13/15 from: http://www.wmich.edu/visionstudies/academics/teacher