| Summary: | 碩士 === 大同大學 === 通訊工程研究所 === 94 === Wavelet transform is the new theory that has been developed in these years, and wavelet transform applied to frequency and time domain characteristics. Due to wavelet transformation has multi-resolution analytical characteristic, which can use wavelet transform to analyze defects of structural texture possible.
The FPCB board is constructed from three structural textures: vertical, horizontal or oblique in degrees of 45 or 135 diagonal. In the method, the inspection is mainly divided into two parts. First part mainly aims at defects inspection of the horizontal and vertical circuit lines. The part makes wavelet transform in accordance with the original image, and reconstructions of the defect parts existing. The other part will spread the original image to become the new rhombus, and use the DWT transform to detect the defects. So to detect the original images, that can’t turn the images.
In the images input scheme, we integrate CCD camera, robot arm and related hardware to catch the images of FPCB. There are two parts of image reprocessing, one to solve the ripper effect by slow down the CCD camera scanning speed; the other is to solve the scanning table with the impurity by smoothing the image.
This thesis aims mainly at the defects inspection of the oblique circuit lines on FPCB to lower the operation cost and procession time, and improve the efficiency accuracy and realization possibility of the hardware to reach the goal of automatic defects inspection.
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