A legally blind person with 20/200 vision (with the best corrective lenses) should be 20 feet away from an object to see it, and someone with 20/20 vision could see it 200 feet away. About 80% of blind people still have some vision. It can be difficult to understand how a person with a particular eye condition can see some things without seeing others. While some people lose a lot of vision in a short time, others slowly lose their sight. Many diseases that cause blindness begin to affect a certain part of a person`s vision and then develop to remove more vision. For example, macular degeneration initially affects a person`s central vision (the vision that makes us see straight ahead). Visual examples of what individuals might see if they have diseases such as macular degeneration, glaucoma, cataracts, diabetic retinopathy, and retinitis pigmentosa can be found on the National Eye Institute website at: www.nei.nih.gov. Most of our funding comes from people like you. Throughout 2020, we looked at the impact of COVID-19 on people who are blind or partially sighted and advocated for meaningful responses to the pandemic. This work is only possible thanks to the donations of people like you. If you appreciate the information you found on our website, please make a gift today! Glaucoma accounts for 9-12% of all cases of blindness and is characterized by high pressure in the eyeball. Constantly high intraocular pressure can damage the optic nerve and lead to visual disturbances. If you are completely blind, you cannot see any light or shape.
Among people with eye diseases, only about 15% cannot see anything at all. If you`re legally blind, you can still see – but not so clearly. Legal blindness is a term that applies to people with a certain threshold of visual impairment (20/200 vision). In particular, legal blindness is not the same as total blindness, in which a person cannot see anything at all. A legally blind person may have some sight and be able to see things like shapes and colors. Legal blindness can be the result of accidents or eye diseases, including cataracts and age-related macular degeneration. Those who are legally blind may be entitled to disability benefits such as those offered by the Social Security Administration in the United States. Various government agencies and non-governmental organizations also offer benefits and assistance, including low-visibility tools and other tools or resources to improve day-to-day operations. The visual impairment must be medically verified and validated by an optician or other physician in order for the person to receive benefits. Note that legally blind is not completely blind.
While legally blind people may still be able to see technically, people who are completely blind will not be able to feel the light or see anything at all. Some government agencies also consider the field of vision to determine legal blindness. The field of view is the entire area a person can see, including their peripheral vision, looking straight ahead. Ophthalmologists express the field of view in degrees, with the normal visual field of each eye encompassing more than 120 degrees horizontally and 90 degrees vertically. Someone who has a field of view of 20 degrees or less, even using glasses or contact lenses, is considered legally blind in some countries. This is also known as “tunnel vision,” which means that the individual has difficulty seeing objects on the left and right sides of their body when looking straight ahead. A common test for visual acuity is Snellen`s vision chart. Someone who is legally blind could simply read the top row of the graph, a capital E, while wearing proofreading lenses. The line under the uppercase E is the line for 20/100.
There are also tests that can measure between 20/200 and 20/100. Someone who can`t see the line for 20/100 but sees somewhere between 10/20 and 20/200 would still meet the government standard for legal blindness, which is why it`s listed as “20/200 or less”. Did you know that the largest letter on the chart (an E on most of Snellen`s charts) corresponds to the 20/200 vision. If someone cannot distinguish this letter with his prescribed glasses, he is considered legally blind. Normal vision is 20/20. This means you can clearly see an object 20 feet away. If you are legally blind, your vision is 20/200 or less in your best eye or your field of vision is less than 20 degrees. That said, if an object is 200 feet away, you`ll need to stand 20 feet away from it to see it clearly. But a person with normal vision can stand 200 feet away and see this object perfectly. In the context of legal blindness, these are the consequences of defects or damage in various eye tissues.
The eye is a complex organ, and even the smallest amount of tissue damage can have a significant impact on vision. Total blindness describes a total lack of light and perception of form. In other words, completely blind people cannot see the light and cannot see the form of anything in front of them. Total blindness is rare – 85% of people with eye disease have residual vision, which means that only about 15% of people with eye disease suffer from total blindness. To be considered legally blind, you must meet one of the two criteria of visual acuity (visual acuity) and field of vision (the full range of what you can see without moving your eyes). Part 1 of the United States The definition of legal blindness says this about visual acuity: An optician can diagnose whether a person is legally blind from a standard eye exam using the Snellen card – the standard for measuring vision accuracy in the United States. Measuring visual acuity and/or field of vision can help determine if a person is legally blind. We`ve all heard the term “legally blind,” but what does it really mean? How is this different from complete blindness and who is considered legally blind? If you have a Snellen rating above 20/70 with and without lenses or glasses, you have relatively good eyesight and you are not legally blind or even legally visually impaired. The Iowa Department for the Blind also serves people who are functionally blind. A person is functionally blind when he needs to use so many alternative techniques to perform tasks that are usually performed with vision that his daily lifestyle is significantly altered. These alternative techniques may include reading a newspaper while listening on the phone or using Braille to read a book. Like the term “legal blindness,” “visual impairment” is not a functional definition that tells us a lot about what a person can and cannot see.