Many people use the term visually impaired and blind interchangeably. But there is a clear difference between the two. In this article, we will explain the different terms involved in visual impairment. This will help you be sensitive to the needs of people with different forms of visual disability.
A person suffering from some form of a visual impediment that cannot be fixed by glasses or lenses is termed as visually impaired. The term encompasses all cases where people do not have perfect or near perfect vision.
Blindness is a form of visual impairment. But it is a situation where people cannot see anything. Medically and legally there are several degrees of blindness. To put it simply, all blind people are visually impaired, while all visually impaired are not blind.
A person whose corrected visual acuity is worse than 20/40 or 20/60 is classified as visually impaired. Such people have a visual field of 20 degrees or more.
A person whose visual acuity is worse than 20/400 and has a visual field of 10 degrees or less is classified as blind.
A subsegment of people who have less than 20/200 in the better eye and have a field of vision of 20 degrees or less is termed as legally blind.
Within the visually impaired spectrum, people can have several kinds of impairment. Some may be unable to see in 3D while others may lack peripheral vision. Some patients may have spots in front of their eyes and others may be color blind.
Depending on the level of impairment, a person may use different forms of visual input. For example, some people can read texts in a large font, while others may have to rely on braille. A proper diagnosis will help identify the level of impairment, and the ophthalmologist will be able to suggest the right form of support.