Technical Glossary L*a*b* Color Space

[L*a*b* Color Space]

It is the most common method of describing the color of an object by the L*a*b* color space. This color space is an international standard and is also defined in JIS Z 8729.
In the L*a*b* color space, brightness (lightness) is represented by L* and chroma (saturation) and hue are represented by a* (green-red) and B*(blue-yellow). Positive values on the a* axis represent red, while negative values represent green. Positive values on the b* axis represent yellow, while negative values represent blue. Thus, b* axis values are often used to describe the yellowness of a resin. There is also a “Yellow Index” which is used to quantify yellowness.