In the lame plating industry, how to calculate the color difference value with Colorimeter

Every industry has a set of industry color difference value requirements, especially in the spraying industry, customers have higher requirements for color difference values, and they require that the color color difference value of spraying needs to be within a certain range, which is a lot of people The color difference value △E is very important. So how much range is the value of △E considered standard?

Here we take the color spectrometer as an example to explain it in detail. The main components of the Colorimeter are: light source, integrating sphere, grating, photoelectric Detector and color measurement software. If there are two sets of data measured, which are the L, A, and B values ​​of the sample and the standard, and △ represents the change, then the color difference The calculation formula of △E is:
△E=[(△L)2+(△a)2+(△b)2]1/2 
△L=L sample-L standard (brightness difference) 
△a=a sample- a standard (red/green difference) 
△b=b sample-b standard (yellow/blue difference)
We just know the color difference calculation formula is not enough, we must also figure out the meaning of it, in order to better grasp the color difference value The standard range of △E.
Usually, we use △E to indicate the size of the total color difference, the smaller the value, the smaller the color difference, △L indicates the degree of black and white, △a indicates the difference between red and green, and △b indicates the difference between yellow and blue.
△L+ means whiter, △L- means blacker
△a+ means redder, △a- means greener
△b+ means yellower, △b- means bluer
each customer has different standard range for △E, The requirements for △E in different industries are also different, but in general it can be divided into the following stages: 
0 - 0.25△E
The range of △E value is in the above range, which means very small or none; satisfactory matching 
0.25 - 0.5△E 
The range of △E value is in the upper range, representing tiny; acceptable matching 
0.5 -1.0△E 
The range of △E value is in the upper range, representing small to medium; in some individual industrial applications, 
1.0 - 2.0△E  The range of △E value is in the upper range, representing medium; 2.0 - 4.0△E 
is acceptable in specific industry applications 

The range of △E value is in the upper range, which means there is a gap; in very few industry-specific applications, it is acceptable to accept 
more than 4.0△E. 
The range of △E value is in the upper range, which means it is very large; basically unacceptable 

    In the spraying industry, the manufacturer must know which range the customer's requirements for the product are within. After the value measured by the Colorimeter is submitted to him for confirmation, the product will not be rejected because it does not meet the requirements.