IC appearance inspection: machine vision surface defect inspection technology and Application

Date：2022-05-31 15:27:31 Views：1222

Product surface defect detection is a kind of machine vision technology, which uses machine vision to simulate the function of human vision, and carries out image acquisition, processing, calculation, and finally actual detection, control and application from specific objects. Today's consumer electronics consumers are looking forward to seeing flawless products out of the box. Products with scratches, bumps and other defects can result in costly returns and may damage the brand reputation and future business.

At present, quality control operations aimed at preventing surface defects largely rely on manual inspectors. During the production process, these manual inspectors must be keenly aware and immediately make judgments on product quality to ensure that defective products will not be delivered to consumers. However, the faster the production line is, the more complex the product is, or the more fuzzy the defects are, the more difficult it is for manual inspectors to meet the production efficiency requirements while providing absolute quality assurance.

With the development of technology, machine vision detection technology has been widely used in all aspects of manufacturing, and the appearance defect detection is no exception. Next, we will introduce the machine vision surface defect detection technology and its application.

Common applications of machine vision inspection technology in appearance defect detection:

In the appearance defect detection of many industries, we can find that machine vision detection technology plays an important role, such as:

1. Appearance defect detection of new energy batteries, such as whether the pole piece has burrs, and whether the pole piece, lamination and packaging package have wrinkle, crush, pinch, scratch, bump and other adverse defects.

2. Defects such as scratches, exposed copper, dirt and poor dyeing on PCB circuit board.

3. Defects on the surface of semiconductor chips, such as scratches, printing tilt, foreign matter pollution, core leakage, bubble holes on the packaging surface, etc.

4. In the field of hardware accessories, inspect whether screws, bearings, springs and other components have appearance defects such as pits, scratches, missing characters, defects, bends, dirt, scratches and so on.

5. Inspect the LCD screen surface for defects, such as defects, flaws and scratches.

6. Inspect the printing materials for defects such as stains and color differences.

7. Stains, scratches, missing edges, cracks, color discrimination, linear heterochromaticity, printing defects, color difference, etc. on food packaging.

8. Character recognition and character defect detection on the surface of electronic equipment.

9. Detection of defects in the papermaking process in the papermaking industry, such as stains, stains and impurities.

Principle of machine vision appearance defect detection

Machine vision detects the appearance defects of products by using the optical principle. When the light shines on the product surface, various defects will be reflected and refracted by the surrounding environment to produce different results. For example, when uniform light is vertically incident on the product surface, if there is no defect on the product surface, the emission direction will not change, and the detected light is uniform. When defects appear on the product surface, the light emitted will change, and the detected image will change accordingly.

Due to the existence of defects, stress concentration and deformation will occur around the defects, so it is easy to observe in the image. If a transparent defect (such as crack, bubble, etc.) is encountered, the light will be refracted at the defect, and the intensity of the light will be greater than the surrounding light, so the light detected on the target surface of the camera will be enhanced accordingly. If light absorbing impurities such as sand particles are encountered, the light at the defect location will become weak.

In a word, by analyzing the intensity and characteristics of the image signal collected by the camera, the corresponding defect information can be obtained. The above is the IC appearance inspection related content compiled by the creative core inspection team. I hope it can help you. Shenzhen Chuangxin Online Testing Technology Co., Ltd. is a well-known professional testing institution for electronic components in China, with 3 standardized laboratories covering an area of more than 1000 square meters. The scope of testing services covers: testing and verification of electronic components, IC authenticity identification, material selection for product design, failure analysis, function testing, factory incoming material inspection, X-ray testing of components and parts, tape braiding and other testing items.