About wavelengths of light and colour vision
There is a clear difference between the wavelengths of light that make up the visible spectrum and how the human eye converts the information it receives about wavelength into the perception of colour.
- The human eye, and so visual perception, is tuned to the visible spectrum and so to spectral colours between red and violet.
- It is the sensitivity of the eye to this small part of the electromagnetic spectrum that results in the perception of colour.
- Photosensitive cone cells embedded in the retina of each eye respond to wavelengths of light corresponding with spectral colours.
- Explained in simple terms, cone cells distinguish between different colours by determining how much red, green and blue are present when stimulated by their corresponding wavelengths.
- The system used by the human eye to distinguish colours is called trichromacy or trichromatic colour vision.
- The spread of wavelengths that the spectral colour model is concerned with is well suited to a linear arrangement with the shortest at one and the longest at the other.
- The way the human eye determines colour from the presence of three primary colours (red, green and blue) lends itself to a circular, wheel-like arrangement.
- The RGB color model used in digital displays and imaging devices is based on the trichromatic nature of human vision.