PCB导线上下线宽检测算法研究

Study on Algorithms of PCB Conductor Top and Bottom Line Widths Measurement

针对PCB导线的上下线宽的测量，提出了快速而且精确的边缘提取算法。由于采集的显微图像中有很强噪声，一般常用除噪方法很容易破坏图像的边缘信息。采用P—M模型进行除噪，这种方法最大的优点是能够在除噪的同时保护甚至增强图像的边缘；利用Canny算子对降噪图像提取边缘点；最后进行Hough直线拟合。实验证明该方法不仅有很强的抗噪声能力，能够保持边缘信息和测量的精度，并且满足T程测量的实际要求。

In order to measure the top and bottom conductor line widths, a fast and accurate edge extraction method is proposed. Common methods of image denoisiug often lead to blurred edges, especially for heavy-noise contaminated microscopic images. Firstly, P-M model is used to remove noise. This technique can preserves or even enhance prominent edges when removing noise. Canny operator is used to detect the edge in the denoised image. At last, Hough transform is used to detect lines. Experimental results show that the proposed method has strong antinoise capability. The accuracy of line widths measurement is improved. It can be applied to practical engineering measurement system.