Pink Rose Optical Illusion

Stare at the '+' in the middle of the first picture for 20 second, then quickly look at the '+' within the picture of a rose...

You should see now a color image of a rose (pink). This illusion is due to what scientists call ‘color afterimage’ effect. An afterimage is a negative ‘ghost’ of a color seen after prolonged stimulation of the eye. The odd thing about color vision is that pink or magenta color is not in the spectrum of colors (see below), meaning it cannot be generated by a single wavelength of light. Our brains interpret the color sensation of magenta/pink as ‘absence’ of green.


-archimedes-lab