How vision inspection technology is used in PCB board inspection
Source:
Date:2022-03-10

There is a saying: no PCB, no electronics. PCB circuit board is known as the "mother of electronic products". It is a bridge that carries electronic components and connects circuits. It is widely used in various electronic information products. The quality of the PCB directly affects the performance of the product. Therefore, in the production process, the inspection of the PCB circuit board is very important.


The PCB board is an important precision component of electronic products, and its quality has a direct impact on the performance of the product. In other words, the PCB circuit board industry is an industry that wins by quality. Appearance inspection is a very important part of PCB inspection work, and has high requirements for accuracy, efficiency, speed, etc.


About the application of machine vision technology in PCB circuit board inspection

First of all, PCB defect detection consists of two parts: solder joint defect detection and component detection. The traditional detection method adopts manual detection method, which is easy to miss detection, slow detection speed, long detection time and high cost, and has gradually been unable to meet production needs. Therefore, it is of great practical significance to design an efficient and accurate machine vision PCB inspection system equipped with industrial cameras to replace human eyes.

Machine vision detection technology is based on image processing algorithms and is realized through digital image processing and pattern recognition. Compared with traditional manual detection technology, it improves the efficiency and accuracy of defect detection.


Application of machine vision inspection in PCB circuit board inspection

Machine vision inspection is to use CCD or CMOS industrial cameras to capture inspection images and convert them into digital signals, and then process the image digital signals through computer software and hardware technology to obtain the required feature values of various target images, and thereby realize parts. Various functions such as identification or defect detection.


1. PCB identification and classification detection:

Identify the number of the board by visually inspecting the shape, size, and inner hole of the PCB, and matching the black and white feature map of the product loaded into the system.

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2. PCB drilling code detection:

Drill marks are decoded according to encoding rules.

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3. Appearance inspection of PCB pads:

In the PCB production process, there will be a phenomenon that the pads are covered with oil after the development line. Timely detection and detection of problems at this station can reduce a series of subsequent processes and save costs.

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4. Character reading detection:

Detect whether the character code of the PCB board conforms to the standard, whether it is clear and not missing, whether the lines are smooth without bumps, and whether there are defects such as line overlap, ghosting, pitting, deformation, color difference, deviation, misprinting, etc.

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5. Circuit board appearance inspection:

Machine vision inspection technology can realize integrity inspection including PCB, BGA, pin and patch inspection, as well as solder joints, missing components, and wrong orientation. For example: whether there are stains, sundries, pits, and tin slag residues on the surface of the PCB board; whether the surface characters and symbols are clear; whether the tin on the pads is uniform, etc.

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Compared with traditional inspection methods, machine vision inspection has unparalleled technical advantages, such as high precision, fast speed, high efficiency, non-contact measurement, etc., which is widely used in PCB inspection. Haotianchen Technology has been deeply involved in the field of machine vision inspection for many years, providing one-stop machine vision inspection solutions for customers in industries such as circuit boards, new energy batteries, semiconductors, precision hardware, food, textiles and clothing.