Impossible color

"Reddish green" redirects here. Reddish Green is also a place in Reddish, Greater Manchester, UK.
The human eye's red-to-green and blue-to-yellow values of each one-wavelength visible color [citation needed]
Human color sensation is defined by the sensitivity curves (shown here normalized) of the three kinds of cone cells: respectively the short-, medium- and long-wavelength types.

Impossible colors are colors that do not appear in ordinary visual functioning. Different color theories suggest different hypothetical colors that humans are incapable of perceiving for one reason or another, and fictional colors are routinely created in popular culture. While some such colors have no basis in reality, phenomena such as cone cell fatigue enable colors to be perceived in certain circumstances that would not be otherwise.