The human eye can see millions of colors. However, it won’t always distinguish colors from one another accurately. You may perceive two slightly different colors as the same or see differences in objects of identical color depending on your viewing angle and lighting. This creates challenges when communicating about color.
To reproduce an exact desired color every time, manufacturers and designers need ways to quantify a color’s properties and determine the numerical difference between shades. CIELAB or CIE L*a*b* is a device-independent, 3D color space that enables accurate measurement and comparison of all perceivable colors using three color values. In this color space, numerical differences between values roughly correspond to the amount of change humans see between colors.
What Is L*a*b*?
The International Commission on Illumination (CIE) developed the L*a*b* color model in 1976 with the intent of creating a standard for color communication. When creating the CIELAB color space, the CIE drew inspiration from the CIE 1931 XYZ color space, as well as the Munsell color system. All of these models use three data points to define and plot a color.
CIE developed CIELAB to simplify color communication regardless of the device used. The color space is copyright- and license-free, which means you can use it freely and integrate it into any device or system. As a result, organizations in many industries use CIELAB to control color and define color tolerance standards.
What Does CIE L*a*b* Stand for?
The CIE in CIELAB is the abbreviation for the International Commission on Illumination’s French name, Commission Internationale de l´Eclairage. The letters L*, a* and b* represent each of the three values the CIELAB color space uses to measure objective color and calculate color differences. L* represents lightness from black to white on a scale of zero to 100, while a* and b* represent chromaticity with no specific numeric limits. Negative a* corresponds with green, positive a* corresponds with red, negative b* corresponds with blue and positive b* corresponds with yellow.