Colour contrast
Certain eye conditions can make it difficult to perceive colour. This can make reading difficult when colours of text and background in a document are poorly contrasted.
Proper use of colour can really improve the readability of a document for people with sight loss.
Basic techniques
High contrast must be provided between text and background colours. Pale blues and grey will not be easy to read on white backgrounds but dark blues, black or reds will.
Colour blindness affects the way that certain colours differ from others. Red and green, for instance, can appear to be virtually the same to some users. Ensure that you choose colours that have a good differentiation for people with colour deficiency.
Images must also have good contrast, especially if there is text on the image. Always check that logos are high contrast and tag lines within logos are readable.
Bold and large fonts can sometimes compensate for poor colour contrast
Background images can sometimes interfere with the legibility of text. Watermarks or patterns can be problematic so where possible avoid them, or ensure they are either not behind text or that they do not interfere with its legibility.
Useful resources
- Date: July 2009
