How to control product color difference in production with colorimeter

The colorimeter is a color deviation testing instrument, which can automatically compare the color difference (color difference value) between the sample and the tested object（ Δ E）。 That is, to make a filter that simulates the spectral sensitivity equivalent to the color sensitivity of the human eye, and use it to measure the light of the sample plate. The key is to design the spectral sensitivity characteristics of this sensor, and can measure and display the excellent difference through computer software under a certain light source.

According to the Lab and Lch principles of CIE color space, it can measure and display the color difference △ E and △ Lab values between the sample and the tested sample, distinguish the subtle differences between colors, and achieve the degree of color coincidence.

Colorimeter, also known as chromatic aberration, is a serious defect of lens imaging. Color difference is simply the difference between colors, which occurs when polychromatic light is the light source, and monochromatic light does not produce color difference. The wavelength range of visible light is about 400 to 700 nm. Different wavelengths of light have different colors. The refractive index is also different when passing through the lens. Color difference generally includes position color difference and magnification color difference. The position chromatic aberration causes the image to have color spots or halos when observed at any position, which makes the image blurred. The chromatic aberration of magnification makes the image have color edges. One of the main functions of the optical system is achromatic.

Causes of color difference:
1. Light of various wavelengths will be dispersed in different degrees. White light is dispersed into various wavelengths of light in the ultraviolet, visible and infrared wavebands. When passing through the lens, the image formed has color edges, which is called chromatic aberration. The difference between actual imaging and ideal imaging of optical system is collectively called aberration. Chromatic aberration is one of the aberrations, which is caused by the difference of the transmissivity of the transmission material with different wavelengths, so it can only be seen for polychromatic light.

2. Color perception difference of quantitative representation. It is represented by the difference of the three color attributes of lightness, hue and chroma. The lightness difference represents the difference in depth, the hue difference represents the difference in hue (i.e., red or blue), and the chromaticity difference represents the difference in brightness. The evaluation of color difference is very important in industry and commerce. It is mainly used for color matching in production and color quality control of products. The modern color difference evaluation is based on the standard color difference formula recommended by the International Illumination Association (CIE), and is measured and calculated by color difference meter and computer, and expressed by accurate numbers. Commonly used such as CIE 1976L * a * b * and CIE 1976L * u * v * color difference formula.

3. For products with the same color, there is color inconsistency between batches, and the phenomenon of several color differences between products with the same color is called color difference. It can refer to the color difference between different parts of the same product, the color difference between the same batch of processed products, and the color difference between different batches of products originally dyed with the same color.

In the industry, the product color is required to be consistent. As a result of the above reasons, there will be deviation in the color of the product, which will reduce the quality of the product, and in serious cases, it will lead to the failure of acceptance and delivery. At this time, we need to use colorimeters such as colorimeters to control the color difference of the product color.

1、 Control the quality of our products
To ensure the color consistency of each batch of products, we should first establish a product color standard as the factory standard. A certain amount of samples can be taken from different batches of the same product (hereinafter referred to as product A) for measurement. After measurement, select the products with relatively large color difference from them, and use the products with relatively close color difference as the calibration samples of product A. Measure the color value of the calibration sample in turn with a color difference meter and calculate the average value (the instrument can automatically calculate the average value). Take the average value as the color factory standard of product A and store it in the color difference meter. The storage sample number can be set to 001 for easy memory. If there are multiple products, the factory standard can be measured in sequence according to the above method, and stored as 002, 003, etc.

In the future production process, to check whether the color of product A is qualified, you can call out the standard sample value (data 001) of product A from the color difference meter storage, and then locate it as the standard value. Take samples from each batch of A products for measurement, and the measured color difference value is the result of comparison with the factory standard. Product color difference value（ Δ E) Now most manufacturers control the color difference within 0.5 or 1（ Δ E) If it is within 0.5 or 1, it is considered that there is no color difference, which is unqualified product. If it is more than 0.5 or more than 1, it is considered that there is color difference, which is unqualified product. For other products, the corresponding product factory standard is called out in this way, and the measurement and analysis are carried out after setting it as the standard value.

2、 Production according to standard sample
Many companies order and produce according to the samples provided by the ordering company. They can measure the samples provided by the other party with a colorimeter, store the measurement results in the instrument, and remember the stored sample number as a standard sample. During application, the value of this standard sample shall be called out and set as the measurement standard value, and then the products produced shall be measured in turn, and the product color difference value shall be inspected according to the steps of “Method 1” to evaluate whether the product color is qualified.

Introduction to the development trend of colorimeter:
1. Intelligence: With the rapid development of microelectronics technology, the colorimeter will use microprocessors and sensors with faster operation speed, more complete functions and higher integration, and the colorimeter will be more intelligent and humanized.

2. Precision and high speed: The use of microprocessors and sensors with faster operation speed, more complete functions and higher integration enables the colorimeter to combine more complex algorithms. In addition, due to the development of manufacturing technology, more accurate applications will be realized, integrating the ball and sensor, and the color difference will become more and more accurate and fast.

3. Multi-color space conversion: The high-speed microprocessor allows multiple operations of color difference, so the color difference meter can realize the mutual conversion of cierg, CIEXYZ, CIELAB, cielch and Hunter losses, giving users more choice of test parameters.

4. The PC extends the function of the colorimeter: it provides a serial port connected to the PC computer, which can communicate and transmit data between the colorimeter and the PC. It realizes the function expansion of the chromatic aberration instrument through the chromatic aberration instrument software of PC.

5. Measurement stability: With the development of semiconductor technology, coating technology and efficient algorithms, the measurement data of colorimeter will become more and more stable, and it will be closer to spectrophotometer in color measurement.

Portable Colorimeter/Chroma Meter is an innovation color measuring tool with powerful configuration to make color measurement easier and more professional; It support Bluetooth to connect with Android and ISO devices, Portable Colorimeter/Chroma Meter will take you into a new world of color management. It can be widely used to measure color value, color difference value and find similar color from color cards for printing industry, paint industry, textile industry, etc.

Lisun Instruments Limited was found by LISUN GROUP in 2003. LISUN quality system has been strictly certified by ISO9001:2015. As a CIE Membership, LISUN products are designed based on CIE, IEC and other international or national standards. All products passed CE certificate and authenticated by the third party lab.

Our main products are Goniophotometer, Integrating Sphere, Spectroradiometer, Surge Generator, ESD Simulator Guns, EMI Receiver, EMC Test Equipment, Electrical Safety Tester, Environmental Chamber, Temperature Chamber, Climate Chamber, Thermal Chamber, Salt Spray Test, Dust Test Chamber, Waterproof Test, RoHS Test (EDXRF), Glow Wire Test and Needle Flame Test.

Please feel free to contact us if you need any support.
Tech Dep: Service@Lisungroup.com, Cell/WhatsApp:+8615317907381
Sales Dep: Sales@Lisungroup.com, Cell/WhatsApp:+8618117273997

Tags：CD-320PRO