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研究用于飞行器等动态基座航向角校准的大范围、中高精度航向角度测量系统.系统采用2个面阵电荷耦合装置(CCD)检测反射光斑的相对位置,实时测定动态基座航向角,为避免基座晃动的影响,提出了角锥棱镜反射测量方法并设计了整套光路,所需元件少,结构简单,光路调谐简便,适合空中作业.根据预估参数搭建了实验系统,对面阵CCD传感器的检测信号进行阈值分割处理后,采用重心亚像素检测方法,定位精度达到0.4像元大小,航向角度测量不受基座晃动影响,测量精度优于1',测量范围满足±10°,为应用于外场实验打下了基础. 相似文献
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Atsushi Minato Nobuo Sugimoto Zvi Bleier George C. Hunter James Paul 《Optical Review》1995,2(4):319-322
A 50-cm diameter hollow cube-corner retroreflector for a space application was tested with a 60-cm interferometer. To separate the effect of sag due to gravity, the interferograms were taken at six rotational positions, with the retroreflector mounted horizontally. The zero-gravity dihedral angles and the effect of sag were estimated from the interferograms. 相似文献
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LIN Xu-Ling ZHANG Jian-Bing LUO Feng BEI Hua LU Shan-Liang YU Tie-Min DAI Zhi-Min 《中国物理C(英文版)》2009,33(10)
Based on the femtosecond accelerator device which was built at the Shanghai Institute of Applied Physics (SINAP), recently a modified far infrared Michelson interferometer has been developed to measure the length of electron bunches via the optical autocorrelation method.Compared with our former normal Michelson interferometer, we use a hollow retroreflector instead of a flat mirror as the reflective mirror.The experimental setup and results of the bunch length measurement will be described in this paper. 相似文献
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基于激光动态散斑的时频信号,建立了一套适用于角反射器阵列的微动参数反演算法。首先利用物理光学方法推导了角反射器及角反射器阵列激光散斑的实时强度公式,然后基于短时傅里叶变换研究了散斑功率谱形成机制及其数字特征,最后提出了频谱相关法及时频-相幅变换算法,并采用该方法提取了动态散斑时频谱线周期及振幅分布,反演了三种典型运动状态下目标的自旋周期及旋转轴指向。结果表明:基于几个周期的散斑强度序列,所提反演算法可以得到高精度的旋转周期及视线角,但对旋转轴方位角的反演精度相对较差,需要更多的观测数据才能得到满意的结果。 相似文献
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Atmospheric turbulence affects the transmission of laser pulses through the atmosphere. The effects mean that the peak power of the laser pulses is not stable. For laser pulses reflected by a cooperative target, the peak power instability is greater because of the double-pass propagation of the laser pulses through the same atmosphere. The atmospheric turbulence can be monitored by detecting the peak power instability of echo laser pulses. This paper presents a method for monitoring atmospheric turbulence based on a cooperative target. Comparative experiments are carried out based on using a diffuse whiteboard and a corner-cube retroreflector (CCR) as the cooperative target. The distance between the two terminals of the experimental system is 1550 m. The size of the diffuse whiteboard is 60×60 cm2. The bottom surface of the CCR is a circle with a diameter of 1 in. and the three mirrors of the CCR are coated with silver. Experiment results show that the peak power instability of echo laser pulses retroreflected by the CCR is 28.3%. This is much larger than that diffuse reflected by the whiteboard (11.2%). This indicates that the method based on the CCR has higher atmospheric sensitivity. In addition, the peak power of the echo laser pulses retroreflected by the CCR is also much larger. Therefore, the system based on the CCR is more suitable for monitoring of atmospheric turbulence. 相似文献
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An absolute methodology has been developed for quantification of misalignment of an ultrasonic transducer using a corner-cube retroreflector. The amplitude based and the time of flight (TOF) based C-scans of the reflector are obtained for various misalignments of the transducer. At zero degree orientation of the transducer, the vertical positions of the maximum amplitude and the minimum TOF in the C-scan coincide. At any other orientation of the transducer with the horizontal plane, there is a vertical shift in the position of the maximum amplitude with respect to the minimum TOF. The position of the minimum (TOF) remains the same irrespective of the orientation of the transducer and hence is used as a reference for any misalignment of the transducer. With the measurement of the vertical shift and the horizontal distance between the transducer and the vertex of the reflector, the misalignment of the transducer is quantified. Based on the methodology developed in the present study, retroreflectors are placed in the Indian 500 MWe Prototype Fast Breeder Reactor for assessment of the orientation of the ultrasonic transducer prior to the under-sodium ultrasonic scanning for detection of any protrusion of the subassemblies. 相似文献
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Based on the femtosecond accelerator device which was built at the Shanghai Institute of Applied Physics (SINAP), recently a modified far infrared Michelson interferometer has been developed to measure the length of electron bunches via the optical autocorrelation method. Compared with our former normal Michelson interferometer, we use a hollow retroreflector instead of a flat mirror as the reflective mirror. The experimental setup and results of the bunch length measurement will be described in this paper. 相似文献
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角锥棱镜的远场衍射特性 总被引:10,自引:0,他引:10
角锥棱镜具有空间反射特性,广泛用作激光测距的合作目标,不同的使用情况有不同的精度要求,对用于远距离测距的角锥棱镜其远场衍射特性将直接影响测距效果。通过对角锥棱镜角度误差和面形误差的分析,建立了具有角度误差和面形误差的角锥棱镜的出射波面的波差分布,并按照光波的衍射原理计算具有误差的角锥棱镜的远场衍射图。通过衍射图可以看出出射光束的发散程度随着角度误差的增加而增加,直至完全分离成六束光束。同时,面形误差的增加将导致衍射图的急剧恶化,使出射光束的质量明显降低。角锥棱镜的衍射特性对角锥棱镜的设计和评价具有指导意义。 相似文献
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