The intent of this Success Criterion is to provide enough contrast between text and - its background so that it can be read by people with moderately low vision (who do - not use contrast-enhancing assistive technology). For people without color deficiencies, - hue and saturation have minimal or no effect on legibility as assessed by reading - performance (Knoblauch et al., 1991). Color deficiencies can affect luminance contrast - somewhat. Therefore, in the recommendation, the contrast is calculated in such a way - that color is not a key factor so that people who have a color vision deficit will - also have adequate contrast between the text and the background. +
The intent of this Success Criterion is to provide enough contrast between text and its background, so that it can be read by people with moderately low vision or impaired contrast perception, without the use of contrast-enhancing assistive technology. +
+For all consumers of visual content, adequate light-dark contrast is needed between the relative luminance of text and its background for good readability.
+ Many different visual impairments can substantially impact contrast sensitivity, requiring more light-dark contrast, regardless of color (hue).
+ For people who are not able to distinguish certain shades of color — often referred to as color blindness
— hue and saturation have minimal or no effect on legibility as assessed by reading performance.
+ Further, the inability to distinguish certain shades of color does not negatively affect light-dark contrast perception.
+ Therefore, in the recommendation, contrast is calculated in such a way that color (hue) is not a key factor.
Text that is decorative and conveys no information is excluded. For example, if random @@ -318,7 +317,18 @@