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1.
针对线阵相机的特点,论文提出了一种线阵相机标定方法。首先,利用设计的平面靶标与相机多次曝光巧妙地构建了虚拟立体标定靶标,通过分析与数学建模得到靶标上标定特征点空间位置与像点的对应关系;其次,分别使用最小二乘法与迭代求解的方法对多个特征点的线性参数超定方程与镜头的非线性畸变参数进行求解,讨论了标定过程中相机与靶标非严格平行时对标定结果的影响;最后,实验室条件下使用论文设计的靶标与方法对线阵相机标定进行实验验证。理论分析与实验结果表明此线阵相机标定方法简单灵活,标定特征点个数不拘泥于靶标的制作,相机与靶标的位置无需严格平行,标定精度高,且具有较好良好的实用工程应用价值。  相似文献   

2.
提出一种利用共线的标定特征点确定线阵相机内参的方法。所有标定特征点均在线阵相机的视平面内。首先,标定过程中对标定特征点逐一成像,直接得到标定特征点和其对应像点,解决了空间标定点与像点的对应问题;其次,通过数学建模得到线阵相机的成像模型,联立多个位置处的成像模型解算出相机内参;最后,对影响线阵相机标定的因素进行分析及实验验证。理论分析和实验结果表明,文中的线阵相机标定方法简单灵活,无需制作精密的靶标,可获得大量标定点,提高了线阵相机标定的准确性和稳定性,实验得到成像特征点重投影像点位置偏差均方根为0.37 pixel。  相似文献   

3.
为了提高线阵相机畸变标定和校正的实时性和便捷性,研究并提出了一种基于激光线阵的线阵相机在线畸变标定和校正的方法。以一组相对间隔已知的激光线阵作为基准,根据其相对间隔的变化而实现相机的在线标定和校正,而无需已知相机和成像物体的相对位置,也无需其他设备,操作简单。该方法适用于成像过程中物距不变的情况。经实验证明,当激光线阵中激光线数量为41,且物距为0.25 m时,校正后影像点的位置偏差均方根为0.5685 pixel。  相似文献   

4.
针对线阵相机标定的过程中特征点容易丢失的事 实,提出了一种线阵相机标定方 法。首先,利用设计的平面靶标 与相机多次曝光巧妙地构建了虚拟立体标定靶标,通过分析与数学建模得到靶标上标定特征 点空间位置与像点的对应关系; 其次,使用最小均方估计方法对特征像点中心进行亚像素估计,并使用基于最小二乘迭代方 法对多特征点超定方程进行求解, 讨论了标定过程中相机与靶标非平行时对标定结果的影响;最后,使用提出的方法对线 阵相机标定进行实验验证。理论分析 与实验结果表明,本文的线阵相机标定方法简单灵活,标定特征点个数不拘泥于靶标的制 作,相机与靶标的位置无需严格平行,平 均标定精度达0.26pixel,具有较好的实用价值。  相似文献   

5.
刘海庆  杨凌辉  任永杰  邾继贵 《红外与激光工程》2016,45(11):1117002-1117002(6)
提出了一种基于正交柱面成像相机的大尺寸三维坐标测量方法。正交柱面成像相机由一个正交柱面成像光学系统和两个正交放置的线阵CCD组成,它们分别被用来检测被测点的水平角和垂直角。一个相机决定了两个角度,两个相机交汇,即可实现被测点的三维坐标测量。所提出的方法在精密坐标测量特别是动态位置跟踪方面具有突出的优势。一个灵活的内参标定方法被用来标定正交柱面成像相机,内参标定后相机在水平方向和垂直方向角度测量误差的均值分别为1.85和2.16。另外,双相机的外参标定也被介绍,外参标定后系统的坐标测量精度优于0.52 mm。实验结果表明:所提出的三维坐标测量方法有效,具有良好的测量精度。  相似文献   

6.
精密零部件的高精度三维成像是工业制造和检测的关键任务。针对现有的线激光测量系统效率慢、精度低等问题,提出了利用远心成像的线激光三维测量系统,研究了该系统的标定方法。首先,分别采集不同位置的靶标图像和激光线照射下相同位置的靶标图像,通过远心正交成像标定相机内参矩阵系数和外参位姿关系;然后,建立线激光投影平面与标定目标平面之间的几何关系,求解不同目标平面下的激光线方向矢量,进而通过最小二乘法获得光平面方程;最后,在极大似然准则下,利用Levenberg-Marquard非线性优化算法精确地计算标定参数最优解,搭建了测试系统,开发了专用标定程序。实验结果表明:在60 mm×48 mm的视场下,所设计的系统和方法可以实现优于18μm的测量误差,能够快速准确地重建出三维形貌。  相似文献   

7.
为解决现有线结构光大尺度测量标定复杂、精度不高的问题,提出了一种基于多视觉线结构光传感器的大尺度、高精度测量方法。多视觉线结构光传感器含1个激光器和多个等间距并排的相机(一主多从),相互间有1/3左右重叠视场(OFOV),光束覆盖所有相机视宽。传感器标定只需简易的棋盘格靶标,按张氏标定法采集靶标图像、标定传统参数;此外,考虑相机视角的不变性,利用OFOV内标定图像的已知特征角点,经图像配准可预标定相邻相机图像拼接的变换矩阵。变换矩阵的逐步连乘得到任意从相机图像转换到主相机成像平面的透视变换模型(PTM)。该方法通过各相机同步采集大尺度物体的局部光条图像,再利用PTM将所有局部光条快速拼接成完整的光条图像,最终经光条坐标提取、换算得到光条位置的三维坐标。实验结果表明:与已有方法相比,该方法使用简便、精度更高,重构模型平均构造深度与真实模型仅差8.3%。  相似文献   

8.
一种线阵CCD检测系统的调整和标定方法   总被引:2,自引:0,他引:2  
论述了一种线阵CCD扫描检测系统调整和标定方法.建立了检测系统的几何模型;设计了标定靶标;提出了基于靶标图像的视觉系统调整定位方法.采用灰度矩法对边缘点进行了亚像素定位;根据靶标上特征线的实际坐标和图像坐标对系统进行标定,在工方向采用先线性标定再多项式畸变校正的两步法标定横向扫描区域;在y方向采用线性标定法标定扫描行距.实验结果表明,这种调整和标定方法具有较好的效果和较高的标定精度.  相似文献   

9.
针对当前线阵相机几何标靶标定精度不足的问题,提出了一种基于绝对相位标靶的线阵相机标定方法。针对线阵相机成像特点,设计了结合相位与格雷码的绝对相位编码标靶。标定时首先由线阵相机获取标靶图像,计算标靶的绝对相位;然后在空间不同位置处摆放标靶,采用辅助面阵相机获取标靶间的相对位置关系,建立线阵相机图像与空间点的精确对应关系;最后采用两步法标定获取线阵相机内两相机间的坐标变换关系。仿真与实验结果表明:标定的最大重投影误差为0.089 pixel,与现有方法相比降低了79.78%,所提方法具有良好的抗噪、抗离焦性。  相似文献   

10.
基于圆心真实图像坐标计算的高精度相机标定方法   总被引:1,自引:0,他引:1  
在基于圆点阵二维平面靶标的相机标定方法中,直接在拍摄的标靶图像中提取的椭圆中心并非真实的圆心投影像点,该圆心成像投影偏差必然会降低相机参数标定精度。基于此,提出将标靶图像逆向投影至空间虚拟矩阵以获得真实圆心像点的迭代标定算法。首先,使用椭圆中心提取方法进行平面相机标定;其次,由标定参数和拍摄图像进行逆向投影获得虚拟物理标靶图像,在近似圆虚拟图像上完成圆心坐标提取;再次,将虚拟圆心坐标转化为物理坐标值并投影到图像上,将其作为圆心真实像点坐标值来进行相机标定;最后,经多次迭代投影和标定完成高精度相机标定。模拟和实验结果表明,所提方法将相机标定精度提高约一倍,可为三维重建和视觉测量提供高精度的相机参数。  相似文献   

11.
This paper presents a brief overview of the Applied Centura(R)DPS(R)system,configured with silicon etch DPS Ⅱ chamber, with emphasis on discussing tuning capability for CD uniformity control. It also presents the studies of etch process chemistry and film integration impact for an overall successful gate patterning development. Discussions will focus on resolutions to key issues, such as CD uniformity, line-edge roughness, and multilayer film etching integration.  相似文献   

12.
We have fabricated the white organic light-emitting devices (WOLEDs) based on 4,4' -bis(2,2 -diphenyl vinyl)-1,1' - biphenyl (DPVBi) and phosphorescence sensitized 5,6,11,12,-tetraphenylnaphthacene (rubrene). The device structure is ITO/2T-NATA (20 nm)/NPBX (20 nm)/CBP: x%Ir(ppy)3:0.5% rubrene (8 nm)/NPBX (5 nm)/DPVBi (30 nm)/Alq(30 nm)/LiF(0.5 nm)/A1. In the devices, DPVBi acts as a blue light-emitting layer, the rubrene is sensitized by a phosphorescent material, fac tris (2-phenylpyridine) iridium [Ir(ppy)3], acts as a yellow light-emitting layer, and N,N' -bis- (1-naphthyl)- N,N' -diphenyl -1, 1' -biphenyl-4,4' -diamine (NPBX) acts as a hole transporting and exciton blocker layer, respectively. When the concentration of Ir (PPY)3 is 6wt%, the maximum luminance is 24960 cd/m^2 at an applied voltage of 15 V, and the maximum luminous efficiency is 5.17 cd/A at an applied voltage of 8 V.  相似文献   

13.
To meet the need of automatic image features extraction with high precision in visual inspection, a complete approach to automatic identification and sub-pixel center location for similar-ellipse feature is proposed. In the method, the feature area is identified automatically based on the edge attribute, and the sub-pixel center location is accomplished with the leastsquare algorithm. It shows that the method is valid, practical, and has high precision by experiment. Meanwhile this method can meet the need of instrumentation of visual inspection because of easy realization and without man-machine interaction.  相似文献   

14.
本论文提出一种在多天线MIMO信道相关性建模中小角度扩展近似理论算法,并应用于分析MIMO系统性能。分析中分别对三种不同角能量分布情况下的空间相关性研发快速近似计算法,并同时提出双模(Bi-Modal)角能量分布情况下的近似运算。通过分析这些新方法的近似效率,可以得到计算简单、复杂度低、而且符合实际的MIMO相关信道矩阵,对系统级的快速高效计算法的研究和系统级的评估以及误差分析具有重要的意义。  相似文献   

15.
In order to diagnose the laser-produced plasmas, a focusing curved crystal spectrometer has been developed for measuring the X-ray lines radiated from a laser-produced plasmas. The design is based on the fact that the ray emitted from a source located at one focus of an ellipse will converge on the other focus by the reflection of the elliptical surface. The focal length and the eccentricity of the ellipse are 1350 mm and 0.9586, respectively. The spectrometer can be used to measure the X- ray lines in the wavelength range of 0.2-0.37 nm, and a LiF crystal (200) (2d = 0.4027 nm) is used as dispersive element covering Bragg angle from 30° to 67.5°. The spectrometer was tested on Shengnang- Ⅱ which can deliver laser energy of 60-80 J/pulse and the laser wavelength is 0.35 μm. Photographs of spectra including the 1 s2p ^1P1-1s^2 ^1S0 resonance line(w), the 1s2p ^3P2-1s^2 1S0 magnetic quadrupole line(x), the 1s2p ^3P1-1 s^2 ^1S0 intercombination lines(y), the 1 s2p ^3S~1-1 s^2 ^1S0 forbidden line(z) in helium-like Ti Ⅹ Ⅺ and the 1 s2s2p ^2P3/2-1 s622s ^2S1/2 line(q) in lithium-like Ti Ⅹ Ⅹhave been recorded with a X-ray CCD camera. The experimental result shows that the wavelength resolution(λ/△ 2) is above 1000 and the elliptical crystal spectrometer is suitable for X-ray spectroscopy.  相似文献   

16.
High purity organic-tantalum precursors for thin film ALD TaN were synthesized and characterized.Vapor pressure and thermal stability of these precursors were studied.From the vapor pressure analysis,it was found that TBTEMT has a higher vapor pressure than any other published liquid TaN precursor,including TBTDET,TAITMATA,and IPTDET.Thermal stability of the alkyl groups on the precursors was investigated using a 1H NMR technique.The results indicated that the tertbutylimino group is the most stable group on TBTDET and TBTEMT as compared to the dialkylamido groups.Thermal stability of TaN precursors decreased in the following order:TBTDET > PDMAT > TBTEMT.In conclusion,precursor vapor pressure and thermal stability were tuned by making slight variations in the ligand sphere around the metal center.  相似文献   

17.
Integrated circuits (ICs) intended for increasingly sophisticated automotive applications bring unique test demands. Advanced ICs for applications such as highly integrated automatic braking system (ABS) and airbag controllers combine high voltage digital channels, significant VI demands and precise timing capability. Along with continued missioncritical reliability concerns, the trend toward higher voltage operation and increased device integration requires specialized test capabilities able to extend across the wide operating ranges found in automotive applications. Among these capabilities, automotive test requirements increasingly dictate a need for a cost-effective versatile mixed-signal pin electronics with very high data rates reaching up to 50MHz with a voltage swing of-2 V to +28 V.  相似文献   

18.
This paper reviews our recent development of the use of the large-scale pseudopotential method to calculate the electronic structure of semiconductor nanocrystals, such as quantum dots and wires, which often contain tens of thousands of atoms. The calculated size-dependent exciton energies and absorption spectra of quantum dots and wires are in good agreement with experiments. We show that the electronic structure of a nanocrystal can be tuned not only by its size,but also by its shape. Finally,we show that defect properties in quantum dots can be significantly different from those in bulk semiconductors.  相似文献   

19.
An improving utilization and efficiency of critical equipments in semiconductor wafer fabrication facilities are concerned. Semiconductor manufacturing FAB is one of the most complicated and cost sensitive environments. A good dispatching tool will make big difference in equipment utilization and FAB output as a whole. The equipment in this paper is In-Line DUV Scanner. There are many factors impacting utilization and output on this equipment group. In HMP environment one of the issues is changing of reticule in this area and idle counts due to load unbalance between equipments. Here we'll introduce a rule-based RTD system which aiming at decreasing the number of recipe change and idle counts among a group of scanner equipment in a high-mixed-products FAB.  相似文献   

20.
It is of interest to get appropriate information about the dynamic behaviour of rotating machinery parts in service. This paper presents an approach of optical vibration and deviation measurement of such parts. Essential of this method is an image derotator combined with a high speed camera or a laser doppler vibrometer (LDV).  相似文献   

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