hyperbolic colours

A form of hyperbolic colour — The type of colour perceived when a visual afterimage is viewed on a background of the same colour, resulting in a purer perception of that colour than is ordinarily possible to perceive; usually achieved by staring at a shape in one colour (e.g. cyan) for several seconds, and then immediately looking at a background in the opposite colour (e.g. orange), which is the same colour as the resultant afterimage.