基于S3C6410和WinCE6.0的嵌入式立体摄像系统

针对目前立体对图像同步采集问题,提出一种基于S3C6410处理器和WinCE6.0系统的实时同步采集方案.首先,完成立体摄像模块硬件设计;其次,开发相应的OV3640摄像头驱动程序并定制WinCE6.0操作系统;最后,开发基于DirectShow技术的立体摄像系统应用程序.应用程序利用摄像数据流反馈实现左右格式立体对图像的同步采集,关联左右两路摄像数据流,基于视差约束实现双摄像采集帧同步.系统利用ARM 11处理器的数据处理能力和WinCE系统的可裁剪,提高了嵌入式立体摄像系统的可靠性与便携性.     

单镜头真3D立体摄像技术*

【】针对集成成像技术记录立体图像显示深度小,图像摄取技术要求高等缺点,提出一种单镜头真3D立体摄像系统,并从系统结构、原理、核心元件参数设计、显示效果几方面对系统进行分析。研究表明,单镜头真3D立体摄像系统能记录与呈现更深的三维场景,并可在一定范围内进行焦距调整,其结构简单,有利于真3D立体图像技术推广,具有较高的研究与应用价值。     

激光平面扫描3D测量系统快速标定技术

建立了激光平面扫描3D测量数学模型，提出了一种全新的3D测量系统参数的快速标定方法，设计了由2个完全垂直的平面组成的立体标定靶标，使用1个靶标可同时标定测量系统的摄像机参数和光平面方程参数。采用该方法对激光平面扫描测量系统进行了参数标定，用标定后的系统对标准平面进行了测量，空间测量精度优于0．1mm。     

便携式组合测量系统坐标统一的标定方法

针对便携式结构光测量系统和光学三 坐标测量系统的测量坐标系的全局统一问题,提出了一种基于手眼标定模型的标定方法 。利用 在全局坐标系下固定的平面标靶以及与便携式结构光测量系统具有刚性约束关系的 主动光立体标 靶作为中介坐标系,分别估计便携式结构光测量系统与平面标靶的位姿参数以及光学三 坐标测量系统 与主动光立体标靶之间的位姿参数,然后基于手眼标定模型标定出主动光立体标靶与便携式 结构光测量系 统之间的刚性位姿关系,进而完成便携式结构光测量系统和光学三坐标测量系统的坐标统一 。实验结果表 明,本文方法标定结果相对误差标准差约为0.151mm,标定精度合理 有效,可以实现便携式组合测量系统坐标统一的快速标定。     

基于图像的模拟相机标定方法的研究

从光学测量角度出发,结合计算机主动视觉中的相机标定方法及数字图像处理技术,提出了一种CCD摄像系统畸变校正方法.该法通过使用经纬仪,不需相机做任何运动就能实现全过程的标定.该方法在摄像机模型中全面考虑了镜头的径向畸变,利用图像中心附近点畸变量较小的性质,用中心附近点和全场视点对摄像机内部参数和像差修正参数进行标定,最后由最小二乘法得到摄像系统畸变模型的畸变系数,解决了CCD摄像系统的畸变校正问题.与传统的相机标定不同,畸变校正中仅标定数字图像中像素间距和相机焦距.该法运用了亚像素细分算法,提高了测试系统的精度,是一种简单、有效、实用的标定法.     

基于Matlab的计算机视觉测量中摄像机标定方法研究

本文以视觉测量系统中的摄像机标定为研究对象,以物体在摄像机上所成的像与物体实际的形状之间具有一定的函数关系为基础,以获得该函数参数为目的用Matlab进行摄像机标定。该方法利用了Matlab的工具箱及VC＋＋6.0编译软件,设计标定方法及软件程序,方便准确的完成了单摄像头标定和双摄像头的立体标定,得出摄像机的内部参数和外部参数,简化了标定求解过程,提高了标定速率,并具有良好的移植性,适合于其他视觉测量系统。     

高逼真度3D实时成像与显示系统

3D显示技术应用于航空或医学等领域时,对其真实感和观看舒适度要求很高.介绍了一套双视点3D实时成像与显示系统,并对系统的关键技术和算法实现进行阐述,包括硬件系统的设计、双视点图像的标定、畸变矫正、实时监测与校正、3D效果调整等主要模块.该系统可对3D场景进行高逼真还原,并降低观看者的视觉疲劳感,对运行在动态环境中的应用场景有较好的参考价值.     

利用立体视觉的线结构光参数标定

准确标定系统参数是利用线结构光进行高精度测量的前提,文中提出了一种基于双目立体视觉的线结构光参数标定算法,以期达到在工业现场进行高精度、强鲁棒性标定的目的。算法首先采用Tsai两步法标定摄像机内参数和双目相机坐标系间的刚体变换,然后利用立体视觉极线约束条件匹配双目激光条纹点,并将其重构到三维空间以进行光平面标定。相对于...     

基于单摄像头双目成像系统在计算机视觉中的应用研究

利用单个摄像头和一平面镜的舍体实现了双目成像系统的三维视觉功能,并理论证明了平面镜相对于摄像头按一定条件放置时,利用合体可以得到适于三维立体视觉的图像。在已知舍体内外部参数的情况下,由舍体所得图像进行点的三维立体恢复的理论推导。对合体的标定、内外部参数的确定也进行了理论推导。最终证明,由合体进行三维立体恢复,其实质相当于双目成像。通过实验对合体和一双目成像系统分别进行了标定,利用标定的结果进行了对点的三维立体恢复。结果表明两者精度相当。     

二摄像机式立体摄像系统几个参数的分析

本文分析二摄像机式立体摄像系统几个参数，这些参数是①深度分辨力，②立体摄像区域，③显示畸变量。并且分析了这些参数之间的相互关系。     

Development of the readout system for waveguide multilayer optical card

Waveguide multilayer optical card （WMOC） is a novel storage device of three-dimensional optical information. An advanced readout system fitting for the WMOC is introduced in this paper. The hardware mainly consists of the light source for reading, WMOC, motorized stages addressing unit, microscope imaging unit, CCD detecting unit and PC controlling ＆ processing unit. The movement of the precision motorized stage is controlled by the computer through Visual Basic （VB） language in software. A control panel is also designed to get the layer address and the page address through which the position of the motorized stages can be changed. The WMOC readout system is easy to manage and the readout result is directly displayed on computer monitor.     

Nanoimprint Lithography -A Next Generation High Volume Lithography Technique

IntroductionNanoimprint Lithography is a well-acknowl-edged low cost, high resolution, large area pattern-ing process. It includes the most promising methods,high-pressure hot embossing lithography (HEL) [2],UV-cured imprinting (UV-NIL) [3] and micro contactprinting (m-CP, MCP) [4]. Curing of the imprintedstructures is either done by subsequent UV-lightexposure in the case of UV-NIL or by cooling downbelow the glass transition temperature of the ther-moplastic material in case of HEL…     

Collinear phase-matching study of terahertz-wave generation via difference frequency mixed in GaAs and Inp

The collinearly phase-matching condition of terahertz-wave generation via difference frequency mixed in GaAs and InP is theoretically studied. In collinear phase-matching, the optimum phase-matching wave hands of these two crystals are calculated. The optimum phase-matching wave bands in GaAs and lnP are 0.95-1.38μm and 0.7-0.96μm respectively. The influence of the wavelength choice of the pump wave on the coherent length in THz-wave tuning is also discussed. The influence of the temperature alteration on the phase-matching and the temperature tuning properties in GaAs crystal are calculated and analyzed. It can serve for the following experiments as a theoretical evidence and a reference as well.     

Effects of the alloy compositions on the phonon-polaritons in ternary mixed crystals

Composition dependence of bulk and surface phonon-polaritons in ternary mixed crystals are studied in the framework of the modified random-element-isodisplacement model and the Bom-Huang approximation. The numerical results for Several Ⅱ - Ⅵ and Ⅲ- Ⅴ compound systems are performed, and the polariton frequencies as functions of the compositions for ternary mixed crystals AlxGa1-xAs, GaPxAS1-x, ZnSxSe1-x, GaAsxSb1-x, GaxIn1-xP, and ZnxCd1-xS as examples are given and discussed. The results show that the dependence of the energies of two branches of bulk phonon-polaritons which have phonon-like characteristics, and surface phonon-polaritons on the compositions of ternary mixed crystals are nonlinear and different from those of the corresponding binary systems.     

Influence of PVK ： NPB hole transporting layer on the characteristics of organic light-emitting devices

A doping system consisting of NPB and PVK is employed as a composite hole transporting layer （CHTL）. By adjusting the component ratio of the doping system, a series of devices with different concentration proportion of PVK ： NPB are constracted. The result shows that doping concentration of NPB enhances the competence of hole transporting ability, and modifies the recombination region of charge as well as affects the surface morphology of doped film. Optimum device with a maximum brightness of 7852 cd/m^2 and a power efficiency of 1.75 lm/W has been obtained by choosing a concentration proportion of PVK ： NPB at 1：3.     

New insert layer structure OLEDs

An insert layer structure organic electroluminescent device（OLED） based on a new luminescent material （Zn（salen）） is fabricated. The configuration of the device is ITO/CuPc/NPD/Zn（salen）/Liq/LiF/A1/CuPc/NPD/Zn（salen）/Liq/LiF/A1. Effective insert electrode layers comprising LiF（1nm）/Al（5 nm） are used as a single semitransparent mirror, and bilayer cathode LiF（1 nm）/A1（100 nm） is used as a reflecting mirror. The two mirrors form a Fabry-Perot microcavity and two emissive units. The maximum brightness and luminous efficiency reach 674 cd/m^2 and 2.652 cd/A, respectively, which are 2.1 and 3.7 times higher than the conventional device, respectively. The superior brightness and luminous efficiency over conventional single-unit devices are attributed to microcavity effect.     

Analysis of error performance on Turbo coded FDPIM

Due to variable symbol length of digital pulse interval modulation（DPIM）, it is difficult to analyze the error performances of Turbo coded DPIM. To solve this problem, a fixed-length digital pulse interval modulation（FDPIM） method is provided. The FDPIM modulation structure is introduced. The packet error rates of uncoded FDPIM are analyzed and compared with that of DPIM. Bit error rates of Turbo coded FDPIM are simulated based on three kinds of analytical models under weak turbulence channel. The results show that packet error rate of uncoded FDPIM is inferior to that of uncoded DPIM. However, FDPIM is easy to be implemented and easy to be combined, with Turbo code for soft-decision because of its fixed length. Besides, the introduction of Turbo code in this modulation can decrease the average power about 10 dBm, which means that it can improve the error performance of the system effectively.     

A method for calculating the center position of collimated light

It is a key problem to accurately calculate beam spots＇ center of measuring the warp by using a collimated laser. A new method, named double geometrical center method （DGCM）, is put forward for the first time. In this method, a plane wave perpendicularly irradiates an aperture stop, and a charge couple device （CCD） is employed to receive the diffraction-beam spots, then the geometrical centers of the fast and the second diffraction-beam spots are calculated respectively, and their mean value is regarded as the center of datum beam. In face of such adverse instances as laser intension distributing defectively, part of the image being saturated, this method can still work well. What＇s more, this method can detect whether an unacceptable error exits in the courses of image receiving, processing and calculating. The experimental results indicate the precision of this method is high.     

Preparation and Characterization of TaN ALD Precursors

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.     

Curved crystal spectrometer for the measurement of X-ray lines from laser-produced plasmas

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.