The Blindness Spectrum

When people hear “blind,” they often picture total darkness; this is only one point on a big spectrum. Most people who are blind or low-vision have some sight.

Spectrum Examples

I would argue many people fall under the blindness spectrum! Visual changes are part of life. Here are some examples:

Total blindness: no light perception (NLP), which is quite rare.
Light perception only: can sense light and dark but not detail. Most people we think of as blind have some light perception at the very least.
Low vision / “legally blind”: significant vision loss glasses cannot fully correct. Often plenty of usable sight with magnification and high contrast. Some people with Low Vision identify as blind, while others do not.
Tunnel vision: a narrow central field, like looking through a straw (e.g., glaucoma, retinitis pigmentosa).
Central vision loss: a blurry or missing center with intact edges (e.g., macular degeneration).
Colour vision deficiency (yes, arguably this is under the umbrella!): certain colours are hard to tell apart (i.e., rely on more than colour alone). I am a little colour blind!

Reminder Many legally blind people read screens with large text, zoom, and good contrast. The National Federation of the Blind reflects this huge range of lived experience. And most of all, remember "Blind" is not a bad word!

Tidbits

~90% of employed blind adults read Braille

~1 in 10 blind children in the U.S. are learning Braille today

~4 in 10 working-age blind Americans are employed

Braille literacy is strongly tied to employment, yet far fewer children learn it now than in the 1960s — a gap the NFB calls the “braille literacy crisis.” (Employment data via the NFB's Employment Outcomes for Blind and Visually Impaired Adults.)

Reading without (or beyond) print

One of my favorite resources: the National Library Service for the Blind and Print Disabled (NLS) at the Library of Congress. It's a free library of audiobooks and braille for anyone with low vision, blindness, or a print disability, mailed free or downloaded instantly through BARD.

What this means for your site

You don't need seven different sites. You need one flexible site. The same good habits serve the whole spectrum:

Strong contrast & resizable text for low-vision readers (see Design Tips).
Semantic HTML & alt text so screen readers and Braille displays can work (see Extra Considerations).
Rely on more than just colour — pair it with text, icons, or underlines.
Play nicely with zoom and magnifiers by using flexible, relative layouts.

Next: Photosensitivity.

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