System and method for visual inspection on burrs and stain defects of radio frequency identification (RFID) antennae

Abstract

The invention discloses a method for visual inspection on burrs and stain defects of radio frequency identification (RFID) antennae. The method comprises the following steps of: calibrating a camera device, and then shooting images of each RFID antenna to be inspected through the cooperation of the camera device and a strip-type or backlight source; acquiring the shot images of the antennae, and matching the acquired shot images with images of an antenna template to obtain pre-alignment information; taking off corresponding burrs and stain inspection areas from the images of the antennae according to regions of interest (ROI) on the images of the antenna template and the pre-alignment information; respectively carrying out binary processing on the inspection areas taken off from the images and the ROI, and then carrying out image subtraction; and carrying out blob analysis on residual images subjected to the image subtraction, and determining results of the burrs and the stain defects. The invention also discloses a system for carrying out the corresponding visual inspection. Through the method and the system, the inspection process of the burr / stain quality of the RFID antennae can be carried out efficiently and accurately, and the positions of the defects can be accurately positioned, so that the method and the system are particularly suitable for industrial processing and manufacturing processes of the RFID antennae.

Description

technical field [0001] The invention belongs to the field of RFID manufacturing, and more specifically relates to a visual inspection system and method for RFID antenna burr and stain defects. Background technique [0002] Video recognition, also known as RFID technology, also known as electronic tags, is a communication technology that identifies specific targets and reads and writes relevant data through radio signals. Its basic components include tags, readers and antennas. The tags are composed of coupling elements and chips. Each tag corresponds to a unique electronic code and is attached to the object to mark the target object; the reader is used to read and write or write tags information, while the antenna is used to transmit radio frequency signals between the tag and the reader. Because RFID technology does not need to establish mechanical or optical contact between the identification system and a specific target, and has the advantages of high-speed identificatio...

AI Technical Summary

Problems solved by technology

[0004] At present, high-precision antenna pattern detection equipment is blank at home and abroad. Most of the existing technologies are manually (human eyes directly observe the printing of the antenna substrate) or semi-manual (human eyes observe the printing of the antenna substrate through the camera screen). ) to perform instruction detection, which is not only inefficient and costly, but also difficult to guarantee the accuracy and consistency of the detection conclusions, and greatly limits the development of the RFID antenna tag production industry

In recent years, as the requirements for detection automation have become higher and higher, there has also been a detection scheme for antenna quality that directly detects antenna performance and gives a detection conclusion, that is, directly uses a card reader to measure whether the antenna is qualified. Obviously, this method Not suitable for non-chip antennas

In addition, there are automatic detection schemes that use impedance automatic matching technology for testing, such as the detection scheme mentioned in the article "RFID Tag Antenna Test Rack Design" in the fourth issue of Volume 24 of Weibo Journal in August 2008. These detection schemes Testing based on the electrical performance of the antenna can only detect whether the antenna is qualified, which is suitable for streamlined testing and production, but it cannot clearly point out the problems existing in the manufacturing process

In particular, for appearance defects such as burrs and stains, there is a lack of effective detection methods in the prior art, and it is difficult to accurately know the specific location of the defect

Images