Method for detecting circuit board based on three-dimensional characteristics

Abstract

The invention discloses a method for detecting a circuit board based on three-dimensional characteristics. The method comprises the following steps: acquiring three-dimensional coordinate data on each position of the detected circuit board; extracting each three-dimensional characteristic value according to the three-dimensional coordinate data on each position; judging if each three-dimensional characteristic value meets a standard value; and when the three-dimensional characteristic value does not meet the standard value, confirming the position corresponding to the three-dimensional characteristic value as a defect position. According to the scheme, the three-dimensional coordinate data on each point of the circuit board is collected, treated, compared and analyzed, so that the detecting result is acquired and the defects of all the circuit boards can be detected; the method is not influenced by the environments of oxidation, smudge, and the like; the false detecting rate or false reporting rate caused by the environmental influence is effectively reduced; besides, the sunken defect and the blind hole which cannot be detected by a traditional automatic optical detector can be detected.

Description

technical field [0001] The invention relates to the technical field of optical detection, in particular to a circuit board detection method based on three-dimensional features. Background technique [0002] Printed circuit board (PCB, PrintedCircuitBoard) is the substrate for assembling electronic parts and the key electrical interconnection of electronic products. It is called "the mother of electronic system products". The inspection of printed circuit boards is realized by automatic optical inspection instrument (AOI). [0003] In the process of automatic optical inspection instrument testing printed circuit boards, the existing inspection method is to first obtain the plane image of the product, then compare the plane image with the standard image, and then judge the defect of the inspected product according to the comparison result . Specifically, from the perspective of detecting the features used, existing methods are based on "grayscale features of planar images". ...

AI Technical Summary

Problems solved by technology

This kind of defect will lead to a decrease in intensity or even a change in impedance, which needs to be detected, but the existing detection method based on the gray feature of the image through the AOI instrument cannot detect this kind of defect

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