What Is Legal Blindness?
Definition of Legal Blindness“Legal blindness” is a definition used by the United States government to determine eligibility for vocational training, rehabilitation, schooling, disability benefits, low vision devices, and tax exemption programs. It’s not a functional low vision definition and doesn’t tell us very much at all about what a person can and cannot see. Having low vision means that even with regular glasses, contact lenses, medication, or surgery, you may find it difficult to perform everyday tasks. Part 1 of the U.S. definition of legal blindness states this about visual acuity:
- A visual acuity of 20/200 or less in the better-seeing eye with best conventional correction (meaning with regular glasses or contact lenses).
- If you can only read line 1 (the big “E”) from 20 feet away while wearing your regular glasses or contact lenses, the doctor records your vision (or visual acuity) as 20/200 with best correction.
- Update: In 2007, the Social Security Administration updated the criteria for measuring legal blindness when using newer low vision test charts with lines that can measure visual acuity between 20/100 and 20/200. Under the new criteria, if a person’s visual acuity is measured with one of the newer charts, and they cannot read any of the letters on the 20/100 line, they will qualify as legally blind, based on a visual acuity of 20/200 or less.
- OR a visual field (the total area an individual can see without moving the eyes from side to side) of 20 degrees or less (also called tunnel vision) in the better-seeing eye.
A living room viewed through a constricted visual field. Source: Making Life More Livable. Used with permission.For more information on the definitions of legal blindness, you can read Disability Evaluation Under Social Security, a publication from the Social Security Administration.
Using Low Vision Optical and Non-Optical DevicesLow vision optical, non-optical, and electronic magnifying devices can make it possible for you to do a variety of everyday tasks, including Reading, Writing, and Vision Loss.
Next Steps: What Can I Still Do If I Am Legally Blind?
- You can still read.
- You can still cook.
- You can still work.
- In other words, you can still enjoy life!
- Check out our Getting Started Kit for more ideas to help you live well with low vision.
- Read about Ben Karpilow, a visually impaired attorney who practices disability law in California.
Visual ImpairmentMuch like low vision, there are many different definitions of visual impairment. “Visual impairment” is a general term that describes a wide range of visual function, from low vision through total blindness. Here is an example of the variations in the term “visual impairment” or “visually impaired” from the World Health Organization Levels of Visual Impairment: Moderate Visual Impairment:
- Snellen visual acuity = 20/70 to 20/160
- Snellen visual acuity = 20/200 to 20/400
- OR visual field of 20 degrees or less
- Snellen visual acuity = 20/500 to 20/1000
- OR visual field of 10 degrees or less
Light Perception and Light ProjectionThese terms describe the ability to perceive the difference between light and dark, or daylight and nighttime. A person can have severely reduced vision and still be able to determine the difference between light and dark, or the general source and direction of a light.
- The stereotypical assumption – that people who are blind or have low vision live in a type of “blackness” that sighted people see when they close their eyes – is generally not accurate.
- Although every person sees differently, including persons with low vision, an individual who has light perception/projection can perceive the presence or absence of light. Some people describe light perception as knowing when a room light is on or off, or being able to walk toward a lighted lamp on a table in an otherwise darkened room.