The color saturation index is an indicator used to quantify the ability of a light source or display device to restore color vividness. It is mainly used in lighting engineering, display technology and color management.
Basic definition
The color saturation index (Gamut Index, referred to as Rg) is an indicator that measures the increase or decrease in the saturation of a standard color sample by a light source or display. Its value is based on natural light (Rg=100). Rg>100 means that the color is brighter, and Rg<100 means that the color is darker.
Differences from related indicators
Color rendering index (CRI/Ra): Only evaluates color fidelity, not covering saturation changes;
Color gamut coverage (such as NTSC): Measures the range of colors that can be presented in a display device, but does not directly quantify saturation differences.