论文部分内容阅读
美国先进控制公司经四年研究和工程努力制成了印刷电路板光学检测系统,能自动检测8×10″多层印刷电路板各层的腐蚀电路,检测时间不到一分钟。该系统可用于检测线宽、线间隔、线断开、断路,过量铜、空隙和接地板。测试时,将特殊形状的探测器阵列在整个印刷电路板上扫描,看来这种方法较主掩模和付里叶变换平面等比较系统更为可取。这种系统的关键是探测器阵列(图1),它有三个特征用来测印刷电路板:(1)所有线头在路中。若不在,就断开并表示误差;(2)所有线有最小宽度和间隔。比它们小的是误差;(3)最小铜区要比标准线大得多,但比基板小,它表征断开基片或铜斑点误差。特征1和2足以处理95％印刷电路板误差。阵列中38个探测器应排成使最小电路线宽等于中心环的半径,而最小线间隔等于内、
Advanced Control Company of the United States, after four years of research and engineering efforts, has produced a printed circuit board optical inspection system that automatically detects the corrosion circuit on all layers of an 8x10 "multilayer printed circuit board in less than a minute. Detect line widths, line spacing, line breaks, circuit breaks, excess copper, voids, and ground planes. When testing, a specially shaped detector array is scanned across the entire printed circuit board. More importantly, a system such as a Fourier transform plane etc. The key to this system is the detector array (Figure 1), which has three features for measuring the printed circuit board: (1) all the leads are on the way, and if not, (2) All lines have the smallest width and spacing, and errors smaller than these; (3) The smallest copper area is much larger than the standard line but smaller than the substrate, and it characterizes breaking of the substrate or copper Spot error. Features 1 and 2 are sufficient to handle 95% of the PCB error. The 38 detectors in the array should be arranged so that the minimum circuit linewidth equals the radius of the center ring with the minimum line spacing equal to the inner,