%0 Journal Article %A LI Fei %A FENG Kaiyong %A YUAN Weiqi %T Research on LED Defect Detection Method of Flexible Printed Circuit Board %D 2020 %R 10.3778/j.issn.1002-8331.1812-0127 %J Computer Engineering and Applications %P 227-233 %V 56 %N 5 %X

In order to solve the problem of leakage and stickiness in the production of flexible printed circuit board LED, a set of on-line inspection method of LED stickiness quality based on machine vision is proposed. A large plot of 8,192×70,000 pixels is firstly pre-treated, and the rectangular sieve of zone is used to retrieve the rectangular sieve of zone unless the pads area by using the stencil and traversing the idea to get the pad profile of a single pixel as the positioning template. As asynchronous scale of template matching positioning LED bonding pad area, wick region roundness is calculated by region projection, according to roundness patch of different contrast adaptive parameter Canny edge detection for getting wick edge, the wick edge is fitted to obtain wick coordinates. Lastly, LED defect is judged by wick coordinates, and LED stick deviation is judged by calculating pad coordinates deviation and lamp core coordinates. Field test results show that accuracy of LED leakage detection is 100%, accuracy of stick slant LED detection is 97.3%, and average detection time is 1,583?ms, which proves that the proposed detection method has practical value.

%U http://cea.ceaj.org/EN/10.3778/j.issn.1002-8331.1812-0127