Designing for the Visually-Impaired
Blindness
Blindness is the condition of lacking visual perception due to physiological or neurological factors.
Blind Users
- Do not use a mouse, use keyboard
- May use a screen reader to listen to the content (JAWS, FireVox)
- May use a refreshable Braille display
Accessible Design Techniques
- Provide text description for all images & photos ("ALT" attribute)
- Use meaningful link-naming convention - 'See Training schedule' rather than 'click here' for Training Schedule
- Use proper HTML Markup (h1-h6 header tags, etc.)
- Avoid scripts that require mouse usage
Low-Vision
While low-vision users may not be blind and will not use screen-readers to read content, this group makes up a large part of the workforce and the general population. Certain factors such as age and health contribute to low vision. Learn about the common causes of low-vision.
Low-Vision Users
Accessible Design Techniques
- Limit or eliminate text within graphics
- Have plenty of contrast
- Use relative rather than absolute font sizes
Color-Blind
Another form of visual impairment is Color Blindness. Color Blindness a color vision deficiency in humans, and is the inability to perceive differences between some of the colors that other people can distinguish. It is most often of genetic nature, but may also occur because of eye, nerve, or brain damage, or due to exposure to certain chemicals.
Color Blindness
- Affects 7-10% of the male population
- Affects 0.5% of the female population
- Reds & greens are often indistinguishable
Accessible Design Techniques
- Do not rely on color alone to denote information
- Foreground (text) and background colors must provide enough contrast to allow color blind users with or those using a monochrome screen to view information
- Use additional cues or information to convey content
Resources
To determine whether your images or pages are accessible to color blind persons, test your content with VizCheck
Return to 'How Do I Design for Accessibility?' page