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针对现有球面光学元件表面疵病检测技术研究较少的情况,根据疵病对光的散射特性,提出了一种基于机器视觉技术检测球面光学元件表面疵病的方法。实验分析了光照角度、光强大小和球面光学元件曲率半径对疵病散射光成像质量的影响。并对口径为Φ14mm,曲率半径为13mm的球面光学元件表面进行了检测,实验表明,该技术对元件样品上10μm以下的表面疵病可进行有效的检测。 相似文献
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精密表面缺陷的数字化检测系统研究 总被引:3,自引:0,他引:3
精密表面疵病的自动检测长期以来一直是期待解决的问题。依据显微散射光成像系统对元件表面上的划痕、麻点、气泡等疵病形成暗背景下的亮疵病图像,提出了一个完整的数字化标准的精密表面疵病检测评估体系。首先利用比值匹配原理对xy两方向平移得到的子孔径扫描图像进行拼接。引入数学形态学实现疵病识别。运用膨胀、腐蚀、细化等算法,对二值化图像进行噪声消除,图像分割和特征提取。项目的研究成果已能分辨微米量级的疵病,为建立国内外疵病的数字化标准评价系统提供有力的理论及实验依据。 相似文献
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大口径光学元件超精密加工技术是多种学科新技术成果的综合应用,促进了民用和国防等尖端技术领域的发展,在国家大光学工程的推动下,我国的超精密加工技术取得显著的成果。围绕大口径光学元件“高精度磨削+确定性抛光”超精密加工体系,介绍该领域研究进展及厦门大学微纳米加工与检测联合实验室取得的相关研究成果,主要针对光学元件磨削和抛光两个加工流程,详细分析磨削装备技术、磨削工艺技术、精密检测技术、可控气囊抛光技术、加工环境监控技术和中频误差评价技术等关键技术的研究应用情况。这些技术研究从超精密加工的需求出发,借鉴国内外的研究经验和成果,通过对装备、工艺、检测等各方面整合,形成具有自主知识产权的大口径光学元件磨抛超精密加工体系,从而实现大口径光学元件高精度、低缺陷加工。 相似文献
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针对树脂镜片表面疵病自动化检测的需求,开展了基于机器视觉的树脂镜片表面疵病边缘检测研究.设计一种改进的快速Hough圆检测方法获取镜片图像的感兴趣区域,采用混合滤波消除脉冲噪声和高斯噪声,提出一种基于局部窗口阈值的改进Canny边缘检测算法,选取局部最佳分割阈值,对窗口内的疵病实现精确分割.实验结果表明,该边缘检测算法能够较好地检测疵病边缘细节. 相似文献
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为了对疵病检测仪的精度进行预测并对设计方案的合理性进行验证,基于多体系统理论对疵病检测仪机械运动机构进行了精度建模。用低序体阵列和拓扑结构描述了疵病检测仪的结构特点,提出了疵病检测仪的精度模型,针对光学系统的要求进行了误差分离。基于该精度模型,以典型光学元件为例提出了误差补偿的计算流程,对疵病检测仪的精度进行预测。预测结果表明,光学探头的成像点与待测点沿光学探头光轴方向误差最大值为3.0μm,满足光学探头景深20μm的检测要求,同时光学探头成像点与光学元件待测点垂直于光轴方向误差及光学探头光轴与光学元件待测点处表面法向的夹角均在设计指标内。 相似文献
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基于图像拼接与处理来实现非球面光学元件的初步检测,CCD摄像头首先将采集到的视频信号数据经DM642芯片转换成YuV格式,接着将Y信号(灰度信号)经JTAG口运用RTDX(Real—TimeDateExchange)技术传输到主机端,主机端利用matlab处理接收到的图像灰度数据,采用harris角点算法提取f}{图像角点,运用归一互相关法对角点进行匹配并拼接图像,最后运用sobel算法和canny算法对拼接后的图像进行轮廓提取处理,能有效观测到大尺寸光学元件表面裂纹、划痕等缺陷分布,可以验证这是一种有效的非球面光学元件进行精密加工前的检测方法。 相似文献
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细长孔内壁疵病检测是采用光学、机械、计算机等技术实现深孔内表面疵病的自动观察与检测.该测试系统由光扫描光学成像分系统、CCD摄像分系统、计算机控制及图像处理分系统等组成.被测面的反射像通过内窥镜成像在面阵CCD的光敏面上,CCD输出的视频信号经图像采集卡输入计算机,经图像拼接及图像处理,最终完成疵病的检测与尺寸测量,测量精度可达到0.2 mm.本文重点介绍了细长孔内壁疵病检测的原理、二维光扫描成像技术、图像拼接和图像处理技术,并对总体的检测精度进行了分析.该项检测技术不仅可计算出细长孔内壁疵病的面积大小、方位,还可检测出镀铬层脱落面的大小、方位,内壁裂纹的长度、方位等. 相似文献
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The influence of microobject vibrations on the parameters of the microobject's video image is theoretically and experimentally studied. The spatial coherence of illuminating light, parameters of the optical scheme and television system, and roughness of the object's surface are taken into account. The possibility of video inspection of microobject vibrations on the base of blurred microobject's image, when the amplitudes of vibrations are comparable with the size of the microobject, is considered. It is demonstrated that changes in the spatial coherence may cause changes in the sensitivity and precision of measurements. Theory and experimental results are presented. 相似文献
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Ming Chang Bo-Cheng Chen Jacque Lynn Gabayno Ming-Fu Chen 《International Journal of Optomechatronics》2016,10(2):63-72
An optical inspection platform combining parallel image processing with high resolution opto-mechanical module was developed for defect inspection of touch panel glass. Dark field images were acquired using a 12288-pixel line CCD camera with 3.5 µm per pixel resolution and 12 kHz line rate. Key features of the glass surface were analyzed by parallel image processing on combined CPU and GPU platforms. Defect inspection of touch panel glass, which provided 386 megapixel image data per sample, was completed in roughly 5 seconds. High detection rate of surface scratches on the touch panel glass was realized with minimum defects size of about 10 µm after inspection. The implementation of a custom illumination source significantly improved the scattering efficiency on the surface, therefore enhancing the contrast in the acquired images and overall performance of the inspection system. 相似文献
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Results of experimental investigation into the detection of internal, surface, and subsurface flaws by ultrasonic vibration pulses that are excited and received via different types of EMATs are reported. The sensitivity of the EMA instruments developed is shown to be close to the sensitivity of modern contact flaw detectors. An EMAT and a flaw detector that take advantage of the EMA flaw-detection method for the inspection of surface and near-surface zones of metal products are developed. 相似文献
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Ruifang Ye Chia-Sheng Pan Cheng An Chiang Jacque Lynn Gabayno 《International Journal of Optomechatronics》2018,12(1):1-10
A high-resolution automated optical inspection (AOI) system based on parallel computing is developed to achieve fast inspection and classification of surface defects. To perform fast inspection, the AOI apparatus is connected to a central computer which executes image processing instructions in a graphical processing unit. Defect classification is simultaneously implemented with Hu’s moment invariants and back propagation neural (BPN) approach. Experiments on touch panel glass show that using 100 training samples and 1000?cycle iterations in BPN, the accurate classification of surface defects for a 350?×?350 pixels image can be completed in less than 0.1 ms. Moreover, the inspection of a 43?mm?×?229?mm sample that yields an 800 megapixel raw data can be completed remarkably fast in less than 3?s. Thus, the AOI system is capable of performing fast, reliable, and fully integrated inspection and classification equipment for in-line measurements. 相似文献
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V. A. Novikov A. V. Kushner A. V. Shilov 《Russian Journal of Nondestructive Testing》2010,46(7):507-513
The results of experimental studies on the magnetographic flaw inspection of ferromagnetic articles during the magnetization of a test object with a movable permanent magnet (MPM technique) through a magnetic carrier placed on a test surface are reported. The conditions of the inspection were determined. 相似文献
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V. A. Novikov A. V. Kushner A. V. Shilov 《Russian Journal of Nondestructive Testing》2010,46(7):514-519
The results of experimental studies on the magnetographic flaw inspection of ferromagnetic articles during the magnetization
of a test object with a movable permanent magnet (MPM technique) through a magnetic carrier placed on a test surface are reported.
The conditions of the inspection were determined. 相似文献
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李跃辉 《现代制造技术与装备》2011,(3)
主要阐述了超声波探伤的检测原理、操作方法,以及检测过程中需要注意的问题,给出了人工探伤存在的工作效率低、劳动强度高和检测精度低的问题。提出了压力容器焊缝超声波探伤过程中的自动辅助探伤机构的设计,用以代替人工操作,提高工作效率,提高检测精度。 相似文献