Most people think that if they went blind, it would be like having the lights turned off in a room and they’d be just left in darkness all day but, in reality, about 80% of people with legal blindness still have some form of usable vision. So, what does it mean to be blind vs legally blind?
What is legal blindness?
In most countries including the U.S. there is a legal definition for legal blindness which has two parts as follows:
The first part of the definition states that legal blindness is when somebody has central visual acuity meaning their central vision of what is straight ahead of them is 20/200 or less in his or her better-seeing eye with the correction.
This means that even with the best pair of glasses, contacts, or surgery the very best they can see is 20/200 or worse.
Again, with legal blindness, you can’t see any better than 20/200 with any pair of glasses, contact lenses, or surgery available.
Remember, if your vision is 20/200 or even worse like 20/400 but with good pair of glasses or contacts you can see like 20/20 or 20/15 then you do not have legal blindness because your vision can be corrected.
But there is another part to the definition of legal blindness and that has to do with somebody’s side vision or peripheral vision. If somebody’s ability to see off to their far sides is reduced then they may also have legal blindness.
The standard definition typically talks about if somebody even if they can see well like 20/20 letters straight ahead of them, but their peripheral vision is only 20 degrees or less then they also fit the definition of legal blindness.
Types of vision loss
The definition of legal blindness by the IOWA department for the blind addresses both acuity and the visual field because most eye diseases hit the eye in different ways due to which there are different types of vision loss.
For example, like somebody with macular degeneration, these individuals will lose their central vision so looking straight ahead of them is very difficult making it hard for them to read or recognize families’ faces but it also leaves some of their peripheral vision.
In contrast to somebody who has glaucoma still have some of their central vision, but they lose their peripheral vision, and it slowly becomes worse and worse.
Other common conditions such as diabetic retinopathy or cataract those individuals not only have usually very blurred vision, but they can also have complete blank spots either in part or covering their entire visual field.
Although cataract is an easily treatable eye condition with surgery these days but still across globally it is one of the most common causes of blindness and this can cause not only extremely blurred vision, but it can cause foggy and glare-type eyesight changes that can be debilitating.
Also, different eye and brain injuries as well as other genetic conditions can cause major sources of vision loss as well.
According to the IOWA department for the blind legal blindness is a term used to refer to a person with central visual acuity of 20/200 or less in his or her best eye with the best pair of glasses, contact, or surgery.
In addition, A person with a visual field of 20 degrees or less is also considered as a legally blind person irrespective of his or her visual acuity.