CIE or International Commission on Illumination
For any discussion of colour reproduction properties of colour film or television, it is necessary to provide a strict definition of colour and acquire a quantitive understanding of it.
The CIE model was developed by the International Commission on Illumination, based in France in 1931.
On this ‘colour map’, the horseshoe shaped boundary line around the locum shows the position of the pure spectrum colours. Some of these are identified by their wave lengths in nanometers. The straight line closing the horseshoe shows the positions of the magentas and purples, which are complementary to the greens of the spectrum.