X射线CCD标定及模拟

 在北京同步辐射光源4B7B实验站上,采用透射光栅配X射线电荷耦合元件(CCD)的方法对单色光进行了检验,在优化高次谐波抑制方法后,开展了X射线CCD的灵敏度标定实验研究;在标定数据处理过程中,提出了等效曝光时间的概念,修正了快门开合造成的曝光时间误差。标定实验获得了100~1 500 eV能区CCD的灵敏度,补充了300~600 eV能区CCD灵敏度标定数据,验证了简化模型的正确性。     

大视场星敏感器标定技术研究

大视场星敏感器光学系统,由于畸变量较大,在轨标定过程中,直接采用最小二乘最优估计(LMS)或扩展卡尔曼滤波方法(EKF)无法精确求解其标定参数。在深入分析星敏感器测量误差因素的基础上,对考虑畸变和不考虑畸变两种情况的在轨标定结果进行了仿真对比;指出了标定焦距之前需先标定光学畸变的必要性,并介绍了4种可用于在轨校正光学畸变的方法;提出先标定主点偏差,再标定光学畸变参数,最后标定焦距的标定方法。仿真结果表明,可以采用像面旋转法求取主点偏差,利用高阶多项式方法求取光学畸变参数,畸变校正后,采用LMS和EKF标定算法估计焦距,标定精度达到了3.1μm和2.2μm。对100幅模拟星图处理后,星间角距统计偏差约为传统在轨标定方法的1/10～1/8。     

光纤光谱仪绝对光谱辐射定标新技术

在700 nm～900 nm波段范围内,用1 000℃黑体标定光纤光谱仪(200 nm～1 100 nm),获得其在该波段范围内的绝对光谱响应函数.通过测量光纤光谱仪对不同色温下卤钨灯的光谱响应,将700 nm～900 nm波段的响应函数推延至400 nm～700 nm波段范围,最终得到400 nm～900 nm波段内的绝对光谱响应函数.光纤光谱仪对不同色温下卤钨灯的5次测量结果表明:在550 nm～900 nm范围内,所获得的绝对光谱响应合成不确定度小于3.53%.     

激光斜入射光阴极对束流质量的影响及其优化

 针对美国布鲁克海文国家实验室（BNL）型的光阴极微波电子枪,模拟了不同分布状态的驱动激光脉冲斜入射光阴极对束流质量的影响,给出了改变注入相位和补偿线圈磁场强度对发射度的优化结果。结果表明：光斑椭圆化将会导致发射度的大幅增长,优化效果不理想;波前不同步导致的发射度增长对于纵向高斯分布的脉冲可以得到理想的优化。对于斜入射引起的光斑椭圆化和波前不同步问题给出了光学校正方法及部分测量结果。此外,模拟结果显示,对于横向均匀分布的激光脉冲,适当椭圆度的光斑比圆形光斑更有利于提高电子束质量。     

Calibration of a multiple axes 3-D laser scanning system consisting of robot, portable laser scanner and turntable

A multiple axes 3-D laser scanning system consisting of a portable 3-D laser scanner, a industrial robot and a turntable is demonstrated. By using a criterion sphere, a robot tool center point (TCP) calibration approach is proposed to calibrate the relation between the laser 3-D scanner and the robot end-effector. In this approach, two different translational motions of robot are first made to determine the rotation part, and then at least three different rotational motions are made to determine the translation part. Meanwhile, by using the criterion sphere, a turntable approach is proposed to calibrate the pose of the turntable relative to the robot. In this approach, several rotational angles of turntable and two different heights of the sphere are made to determine the rotational axis of turntable. Experiment is performed on a portable laser scanner mounted on an industrial robot ABB IRB4400 with a turntable. The experiment results show that the two proposed calibration algorithms are stable and flexible. The application of 3-D measurement is also given to demonstrate the effectiveness and stability of the multiple axes 3-D laser scanning system.     

土壤重金属铬元素的激光诱导击穿光谱定量分析研究

利用Nd ∶YAG脉冲激光器(波长:1064 nm)作为光源,在实验室自然大气环境下诱导产生土壤激光等离子体,通过等离子体原子发射光谱法定量分析了国家标准土壤样品中元素Cr的含量.实验上研究了在最佳实验条件下土壤中Cr的LIBS分析谱线,测定了Cr元素的定标曲线.实验结果表明,Cr元素浓度在(60—400)×10^-6范围内,元素含量与光谱线强度之间有较好的线性关系;元素Cr浓度分析测量的相对标准偏差(RSD)为7.89%,定量分析结果与标准值的相对偏差为5.3%,Cr元素的检测限为1 关键词： 土壤污染 定量分析 激光诱导击穿光谱 定标曲线     

Tokamak Experiment and Tokamak Engineering——Development of the Plasma Diagnostics on HL-2A Tokamak

The main mission the HL-2A tokamak is of the experiments on to explore the divertor physics and to investigate the plasma confinement, transport and instabilities with high power auxiliary heating and advanced fuelling, it is necessary to develop more new diagnostics and increase the spatial and temporal resolutions of the measurements for exist system. Up to now, about 30 diagnostic systems have been moved from HL-1M to HL-2A tokamak. Other 10 diagnostic systems are being designed and installed on the device. In developed in last 2 years, will be presented.     

Implementation and experimental study on fast object modeling based on multiple structured stripes

In this paper, a practical structured light-based system for fast object modeling and reconstruction is reported. The system consists of an off-the-shelf digital projector, a video camera and a turntable. The system calibration is implemented accurately and automatically by taking a single image of an illuminated calibration template. The multiple color light stripes emitted by the projector adopt only three colors and the color can be modified easily according to the surface texture of the object. This makes the system widely applicable in many situations, and the assumption about color neutrality, which is a limitation to other similar systems, can be largely relaxed. The registration and merging algorithm is greatly simplified by employing a turntable. The validity and high accuracy of the method are demonstrated by extensive real experiments.     

大视场多CCD拼接相机标定方法研究

介绍了一种多CCD拼接弹道相机的标定方法和步骤,以及标定系统的原理及组成。对相机的光学畸变和大视场拼接物像几何投影关系进行了分析,建立了相机数学模型,并采用最小二乘多元回归分析方法,通过测量相机的内方位元素计算畸变系数,确定了最佳条件下相机数学模型中的各个参数。实验表明利用该方法标定出相机精度方位角测角误差小于10″,高低角测角误差小于15″。     

弹道相机图像分析系统与普通扫描仪精确标定

研制该系统的目的是对弹道干板进行数字化、高精度、高自动化的判读,代替传统上低效率的人工判读方法。该系统使用普通平板扫描仪将弹道相机拍摄到的干板图像进行数字化并对扫描图像进行高精度的标定和修正,再利用数字图像处理技术对于板图像进行分析判读。着重叙述了用分布于待测图像四周的标准正交网络对包括待测图像在内的全场进行标定和修正的方法及实验结果。经过本方法标定和修正后,扫描图像几何标准偏差在2～3μm以内。该判读系统及所用到的扫描仪标定方法,实现了弹道干板的数字化、自动化的高精度判读,使普通扫描仪可用于精度要求极高的工程测量。