The working principle and use method of Weifu color difference meter

For the color management field of printing and dyeing, paint, textile and other industries, color difference is unavoidable. In order to minimize the color difference in the production process, we need to use a professional color difference meter to detect color matching. This article takes the Weifu color difference meter as an example to introduce its use method and color difference calculation formula.

A Colorimeter generally refers to a portable Colorimeter, also known as a Colorimeter. This is a typical photoelectric integral object color measuring instrument, which is widely used in the quality management of color products in the industrial field. Of course, what is mentioned here is a simple color difference meter. However, with the continuous development of the color detection industry, more and more sophisticated Spectrophotometer s are used by more and more companies. With professional color matching software, your color management work is more convenient.

The color difference meter uses the standard light source inside the instrument to illuminate the measured object, and detects the tristimulus value and chromaticity coordinates of the object through transmission or reflection. When two close colors need to be measured, the two to be compared can be calculated according to different color difference formulas. Color chromatic aberration. Different instruments are generally equipped with a dedicated violation system, which can perform output operations such as signal acquisition, data processing, and test result display and printing for the tested color sample.

However, due to the different measurement principles and color difference calculation formulas used by different color difference meter products, the final color difference results will also be different.

The principle of color difference meter

The user's operating habits will be considered in the design of the current Colorimeter, and various portable Colorimeters are favored by the majority of users. Usually the color difference meter is composed of illumination light source, photoDetector, signal amplification, data processing unit, result display and printing. Silicon photoelectric devices are commonly used in photoDetectors, and each has three correction filter sheets to match its spectral response with the CIE spectral tristimulus value curve.

This type of instrument can be used to measure the tristimulus value and chromaticity coordinates of reflective or transmissive color samples under the illumination of a certain CIE standard light source. If it is necessary to measure the fluorescence-related properties of fluorescent objects, CIE standard illuminant D65 with ultraviolet radiation is required as the lighting source, so as to truly reflect the color characteristics of fluorescent objects.

The accuracy of the color difference meter is related to the degree to which its spectral characteristics meet the Luther condition. Usually, in the spectral correction of the color difference meter safety Detector, it is impossible to fully meet the Luther condition, and it can only be approximated as much as possible. In addition, the measurement accuracy of the Colorimeter is closely related to the stability of the light source and light Detector of the sea area instrument. We need to pay attention to these when choosing a Colorimeter!

How to use the Colorimeter

1. Take off the lens protection cover and check whether there is any dirt and scratches on the Detector.

2. Connect the power supply and turn on the power switch of the Colorimeter. (The desktop color difference meter needs to be connected to the computer)

3. Click "Calibrate", and follow the system prompts to calibrate with the standard blackboard and standard whiteboard in turn. Press the (calibration) key, then press the (color space selection) key to make it in the Y, X, Y system, point the probe to the center of the white calibration plate, press the (measurement) key, and wait for the light to appear three times, confirm the display Whether the data is consistent with the data in the box (generally refers to the data corresponding to the D65 light source). 

4. Use the matching quartz measuring cup to load an appropriate amount of sample standard, press "test standard sample", and measure the sample standard sample according to the system prompts.

5. Color difference is a commonly used color index in quality management. When measuring color difference, the correct method is to use the target color plate as a standard to adjust the standard of the instrument. The input standard value should be the tristimulus value of the target color plate, which can be the decalibrated data or the value measured by the instrument. It should be noted that color differences are only meaningful when comparing two samples of similar color. In addition, the color difference units of different color difference formulas are different.

6. After the experiment is completed, turn off the Colorimeter, computer host, display screen and voltage regulator in turn, and return the instrument to its original position.