The foundation of the trichromatic colour theory lies in understanding the physiological basis for the subjective experience of colour. It seeks to explain how our eyes and brains work together to create the rich world of colour we see around us.
- Contemporary versions of trichromatic colour theory developed from several parallel lines of research:
- One crucial discovery involved experiments around 1850. In these experiments, people were able to match a variety of coloured swatches by adjusting the intensity of three coloured lights – one red, one green, and one blue. This research showed that by carefully adjusting the intensity of these three coloured lights, a person could match a wide variety of colours. This led to the conclusion that any colour within the visible spectrum could be produced by mixing these three specific colours of light.
- Another important line of research, beginning in the early 19th century, focused on understanding the structure of the human eye. This research revealed the function of rod and cone cells, along with other types of neurons found within the eyeball.
- Systematic research into the relationship between the stimulation of the retina by different wavelengths of light and the corresponding subjective experience of colour reached maturity during the 1920s.
- The discovery that mixtures of red, green, and blue light at different levels of intensity could be used to stimulate the L, M, and S cone types to produce any human observable colour provides the underpinning for almost every form of colour management in practice
- The outcome of this inquiry into trichromacy was the LMS colour model and the CIE (1931) XYZ colour space (among others).