International Commission on Illumination refers to the third-degree color space, based on the mathematical color module of human visual sensitivity to light, its three-dimensional space L*=brightness, a*=space-red-green axis, b*=space Blue-yellow shaft. CIEL*a*b* is a three-degree color space based on human color sense. It is the most widely used color space of CIE. L*a*b* color space is based on that one color cannot be green and red at the same time, nor can it be The theory of blue and yellow, the results may be a single shade can be used to describe the red / green and yellow / blue attributes. The CIEL*a*b* space represents the color associated with the reference white point, which is the specific meaning of white light, and is usually based on the white light that a device can produce. The CIE color space constitutes an independent color base for devices used for color management.