共查询到17条相似文献,搜索用时 125 毫秒
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针对在球栅阵列(BGA)气泡检测中,由于图像干扰因素的多样性导致焊球存在边缘气泡与背景之间灰度级接近,从而造成焊球气泡分割结果不精确的问题,提出了一种结合全卷积神经网络(FCN)和K均值(K-means)聚类分割的焊球气泡分割方法。首先根据所制作的BGA标签数据集搭建FCN,通过训练该网络得到合适的网络模型,再对待测BGA图像进行预测处理得到图像的粗分割结果;然后对焊球区域映射提取,通过同态滤波法提高气泡区域辨识度,再使用K-means聚类分割对图像进行细分割处理,得到最终分割结果图;最后对原图焊球及气泡区域进行标注识别。将所提出的算法与传统BGA气泡分割算法进行对比,实验结果表明,所提出的算法对复杂BGA焊球的边缘气泡分割精确,图像分割结果与其真实轮廓高度匹配,准确度更高。 相似文献
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点模式匹配是视觉测量中的一种新方法;针对贴片机生产中BGA芯片的图像识别对中问题,系统地介绍了BGA的视觉检测任务,提出了基于点模式匹配的快速定位算法;该算法针对BGA焊球分布特点,对传统点模式匹配算法进行优化,大大减少了运算量;现场实际运行结果表明该算法的速度和精度都能满足实际生产的需要,并具有较强的鲁棒性。 相似文献
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《电子制作.电脑维护与应用》2021,(16)
很多电子产品采用塑封球栅阵列封装(PBGA)器件,由于BGA焊点隐藏在芯片底部,装配后不利于检测,存在很大的质量隐患。本文首先对某产品的BGA虚焊原因进行分析,然后根据受筛产品的特性、温箱使用效率和经济性,最后设计了一种温度循环+振动的综合应力筛选办法。结果表明,综合试验筛选度优于0.98。该方法既节省了筛选时间,又提高了产品可靠性,实际应用也更易操作。能够满足批量生产产品筛选的需要,为综合环境试验的应用提供了技术支撑。 相似文献
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给出一种基于图像信息估计被测浮球及其中心轴孔空间姿态的视觉检测方法.若相机焦距已知,且给定空间球与圆特征的形状参数,则可由单视方法估计该球心与圆特征中心位置及其法向方向.基于该算法,可实现对被测球体中心轴端面法线方向的估计,同时还可估计出被测球体及端面中心的位置,从而实现对目标浮球位置及姿态的非接触测量.数值仿真及实际图像处理结果表明了该算法的有效性. 相似文献
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“翻转芯片焊球点阵排列”是一种表面贴片封装技术,使用翻转芯片与焊球点阵排列相结合的结构。然而,芯片封装的最终质量受制作中每个工艺过程的影响。因此,对于某些工艺流程的实时检测将会在整个工艺流程中起到及其重要的作用。非接触检测技术不但可以检测到芯片中的微观特性,对器件不会造成损坏,而且诸如自动光学检测,自动X射线检测等还能提供良好的工艺控制信息。本文概述了FCBGA芯片封装生产工艺特点以及封装工艺流程,并介绍了运用于其中的光学检测和X射线检测等几种非接触检测技术,着重介绍其中的自动光学检测的基本原理及检测算法,这些方法对于芯片封装工艺中的缺陷检测有重要意义。 相似文献
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针对BGA封装的FPGA焊点故障频发的问题,提出了一种基于FPGA的BGA焊点失效监测模型及实现方法;对FPGA的BGA焊点失效原理进行了分析;基于IPC7095B确定了焊点易失效区域,并依据欧姆定律构建了检测模型;基于Xilinx的FPGA实现了对焊点健康信息的管理,并根据不同的检测标准对检测情况进行了比较 相似文献
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Stereo Light Probe 总被引:1,自引:0,他引:1
In this paper we present a practical, simple and robust method to acquire the spatially‐varying illumination of a real‐world scene. The basic idea of the proposed method is to acquire the radiance distribution of the scene using high‐dynamic range images of two reflective balls. The use of two light probes instead of a single one allows to estimate, not only the direction and intensity of the light sources, but also the actual position in space of the light sources. To robustly achieve this goal we first rectify the two input spherical images, then, using a region‐based stereo matching algorithm, we establish correspondences and compute the position of each light. The radiance distribution so obtained can be used for augmented reality applications, photo‐realistic rendering and accurate reflectance properties estimation. The accuracy and the effectiveness of the method have been tested by measuring the computed light position and rendering synthetic version of a real object in the same scene. The comparison with standard method that uses a simple spherical lighting environment is also shown. 相似文献
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Yokoyama Y. Endo K. Iwasaki T. Fukumoto H. 《Journal of microelectromechanical systems》2009,18(2):316-321
We have developed a molten-solder ejection method by which molten-solder droplets from a 13- (1 pL) to 450- mum (48 nL) diameter could be realized. This method has been developed as a technique to supply small solder balls. The authors have developed a newly designed solder ejection head and confirmed that solder balls with almost no surface oxidation can be formed by using this method. The diameter of the molten-solder droplets using an advanced head is 13 mum, which is much smaller than the 35 mum of a conventional minimum droplet. As the relative positioning accuracy, a standard deviation of 0.81 mum was achieved when the diameter of the solder droplets was 13 mum. Furthermore, by changing the drive waveform of the conventional head, we enlarged the diameter of the solder droplets to 450 mum, which was much larger than 200 mum of a conventional maximum droplet. In this case, the standard deviation of 26 mum as the relative positioning accuracy was also achieved when the diameter of the solder droplets was 450 mum. 相似文献
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Surendar A. Adi Siswanto Waluyo Alijani Maryam Alhaifi K. Salmani Mohammad 《Microsystem Technologies》2019,25(10):4027-4034
Microsystem Technologies - The purpose of this work is to show the effects of drop impact on the creep-fatigue evolution of solder balls in an electronic device. Finite element method analysis was... 相似文献