Precision Colorimeter Numbers and the Meaning of Letters

The Colorimeter is mainly used in textile and apparel, plastic, paint ink, printing and other industries, among which the color difference in the automotive industry should be the most extensive. So what do the values ​​and letters of the precision Colorimeter mean? The following article briefly introduces this.

1. The meaning of the value of the Colorimeter

The color difference meter is mainly based on the Lab principle of the CIE color space to measure the color difference △E and △Lab value of the displayed sample and the sample of the detected object.

The following are the meanings of the four sets of color difference data: △E, △L, △a, △b:

ΔL----Indicates the deviation value of black and white; positive numbers represent partial whiteness, and negative numbers represent partial blackness.

Δa----represents the deviation of red and green; positive numbers represent reddish, negative numbers represent greenish.

Δb----represents the amount of yellow-blue deviation; positive numbers represent yellowish, negative numbers represent blueish.

ΔE----represents the comprehensive deviation value of color difference. It is numerically equal to the square sum of the above three variables and then the square root.

2. The meaning of the letters of the Colorimeter

(1) Brief introduction of CIE (International Commission on Illumination) Lab color space

L: (brightness) axis represents black and white, 0 is black and 100 is hundreds

a: (Red-Green) The positive value of the axis is red, the negative value is green, and 0 is neutral.

B: (yellow blue) axis positive value is yellow, negative value is blue, 0 is neutral.

(2) The CIE LCH color model uses the same color space as L*a*b*, but it uses L to represent the lightness value; C to represent the saturation value and H to represent the hue angle worth the cylindrical coordinates (only a few industries use it) .

(3) The meanings of other letters detected by the Colorimeter:

R: red

G: Green

B: blue

The three-stimulus value of the CIE 1931 standard chromaticity system is represented by XYZ. Y means chromaticity and brightness, also known as the brightness factor, and XZ only means that the chromaticity has nothing to do with brightness.