Additive Colour System The principle of the additive colour system is based on the ability to map the colour gamut by using three primaries that lie as close to the ‘corner’s of the CIE colour gamut as possible: a saturated red, blue and green would be ideal. By mixing these three colours at different ratios it is then possible to reproduce any colour within the triangle spanned by the three primaries. Of course additive colour systems work with any colours and not just red, green and blue (RGB) but one gets the best coverage of the visible colour range with those primaries. Conventional LED feature a very saturated colour (for red, green and blue LED) and the triangle spanned by the three Nichia LED colours we are using will be much larger than for example the triangle spanned by the primaries of a liquid crystal or cathode ray tube computer monitor. Additive Colour is used in almost all computer displays as well as outdoor signs using LED, etc.