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物理 2002年第1期31卷 17-21页

作者：顾玉宗干福熹中国科学院上海光学精密机械研究所

被动光学限幅器是利用介质的非线性光学性质实现对光的强度进行控制的器件 ,它在科研、军事和民用方面都具有广泛的应用 .文章讨论了被动光学限幅器的反饱和吸收、双光子吸收、自由载流子吸收、非线性折射、光致散射和光折变机制 ,每种... 详细信息

被动光学限幅器是利用介质的非线性光学性质实现对光的强度进行控制的器件 ,它在科研、军事和民用方面都具有广泛的应用 .文章讨论了被动光学限幅器的反饱和吸收、双光子吸收、自由载流子吸收、非线性折射、光致散射和光折变机制 ,每种机制在光限幅器应用中的有效性及局限性 ;介绍了国内外研究状况及自己的工作 ;指出了今后被动光学限幅器研究的发展方向 .

关键词：被动光学限幅器非线性吸收非线性折射光致散射光折变非线性光学强度

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顾及最优分配和最佳掩码的点云部件分割

光学精密工程 2024年第12期32卷 1941-1953页

作者：陈西江孙曦赵不钒安庆韩贤权武昌理工学院人工智能学院湖北武汉430223 武汉理工大学安全科学与应急管理学院湖北武汉430070 东华理工大学自然资源部环鄱阳湖区域矿山环境监测与治理重点实验室江西南昌330013 长江水利委员会长江科学院湖北武汉430019

为了增强网络的泛化能力,提升部件分割的精度,本文提出了一种顾及最优分配和最佳掩码的点云部件分割方法。首先,根据推土机距离定义两个点云之间的最优分配;然后利用最远点采样对点云分组,计算每个分组中点的显著性,再利用球查询确定点... 详细信息

为了增强网络的泛化能力,提升部件分割的精度,本文提出了一种顾及最优分配和最佳掩码的点云部件分割方法。首先,根据推土机距离定义两个点云之间的最优分配;然后利用最远点采样对点云分组,计算每个分组中点的显著性,再利用球查询确定点云的最佳掩码,以保留原始点云的语义信息;最后,将一点云中显著性高的点的邻域替换掉另一点云中显著性低的点的邻域,从而实现点云之间的混合增强。本文在ShapeNet数据集上进行验证,使用本方法进行增强数据再输送到PointNet,PointNet++以及DGCNN模型中,其mIoU从83.7%,85.1%,85.1%分别增加到了85.1%,86.3%以及86.0%,有效提升了部件分割的效果。

关键词：数据增强点云部件分割显著性

维普期刊数据库博看期刊

Double-theodolite measurement systemusedinthei mage calibration of space photographic instrument

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Optoelectronics Letters 2005年第3期 59-62页

作者： LI Yan~(1,2**), QIAO Yan-feng~1, SU Wan-xin~1, and LIU Ze-xun~11.Changchun institute of optics,Fine mechanics and Physics,chinese academy of sciences,Changchun 130033,Chi-na2.Graduate School of chinese academy of sciences, Beijing 100039,china

The purpose of characterizing the image of space photographic instrument is to gain the space included angles from three coordinate axes in the three-dimensional coordinate of the image and the directionality of the three axes of coordinate in the frame of axes of the instrument. The two reference frames will keep in the same direction finally by adjusting according to space angles. This problem was solved by a new high-precision measurement system composed of a double-theodolite and a set of communication system. In the survey system, two TDA5005 total stations from Leica Company will be selected as the double-theodolite and the interdependence of both coordinate systems can be achieved by moving the stations only at one time. Therefore, this measurement system provides a highly efficient and high-precision surveying method to the image calibration of the space photographic instrument. According to the experiment, its measuring accuracy can reach arc-second level.

关键词： Double-theodolite measurement systemusedinthei mage calibration of space photographic instrument

High-Resolution ＆ High-Speed Rotary Fourier Transform Spectrometer

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High-Resolution ＆ High-Speed Rotary Fourier Transform Spect...

Study on snowmelt runoff simulation in the Kaidu River basin

2nd International Symposium on Advanced Optical Manufacturing and Testing Technologies

作者： Yang xiaoxu Zhou Sizhong Lu Qunbo xiangli Bin Zhou Renkui xi’an institute of optics and precision mechanics CAS xi’an 710068

＜正＞Rotary Fourier Transform Spectrometer （RFTS） contains a rotary refractor, which produces continuous variational optical path difference （OPD）. This specialty makes RFTS suitable to high speed spectrum measuring. Maximal OPD can increase so easily through increasing maximal sampling angle from which the system can get high resolution reconstructed spectrum also. Depending on rotating refractor to produce OPD brings some important advantages such as good immunity to outside influences, light weight, small size, etc. The basic theory of this new kind of spectrogram measuring instrument is introduced. OPD is the most important aspect to be considered in studying or designing a Fourier Transform spectrometer（FTS） system. OPD formulas of RFTS are deduced. RFTS has nonlinearity of OPD, which brings interferogram periodicity drifting and reconstructed spectrum noise. The index of OPD nonlinearity is defined and important aspects of nonlinearity are analyzed, including relationships with the refractor’s refractive index and the rotating angle. Replacing OPD in Fourier Transform with nonlinear OPD of RFTS can buck the error of nonlinear OPD in reconstructed spectrum, and computer simulation shows the method effective

关键词： rotary Fourier Transform spectrometer optical path difference nonlinearity

来源： cnki会议评论

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Science china Earth sciences 2007年第S1期 26-35页

作者： ZHANG YiChi1, LI BaoLin1, BAO AnMing2, ZHOU ChengHu1, CHEN xi2 & ZHANG XueRen3 1 institute of Geographic sciences and Natural Resources Research, chinese academy of sciences, Beijing 100101, china 2 xinjiang institute of Ecology and Geography, chinese academy of sciences,ürümqi 830011, china 3 xinjiang Tarim River Basin Management Bureau, Korla 841000, china

Alpine snowmelt is an important generation mode for runoff in the source region of the Tarim River basin, which covers four subbasins characterized by large area, sparse gauge stations, mixed runoff supplied by snowmelt and rainfall, and remarkably spatially heterogeneous precipitation. Taking the Kaidu River basin as a research area, this study analyzes the influence of these characteristics on the variables and parameters of the Snow Runoff Model and discusses the corresponding determination strategy to improve the accuracy of snowmelt simulation and forecast. The results show that: (i) The temperature controls the overall tendency of simulated runoff and is dominant to simulation accuracy, as the measured daily mean temperature cannot represent the average level of the same elevation in the basin and that directly inputting it to model leads to inaccurate simulations. Based on the analysis of remote sensing snow maps and simulation results, it is reasonable to approximate the mean temperature with 0.5 time daily maximum temperature. (ii) For the conflict between the limited gauge sta-tion and remarkably spatial heterogeneity of rainfall, it is not realistic to compute rainfall for each elevation zone. After the measured rainfall is multiplied by a proper coefficient and adjusted with runoff coefficient for rainfall, the measured rainfall data can satisfy the model demands. (iii) Adjusting time lag according to the variation of snowmelt and rainfall position can improve the simulation precision of the flood peak process. (iv) Along with temperature, the rainfall increases but cannot be completely monitored by limited gauge stations, which results in precision deterioration.

关键词： snowmelt runoff model (SRM) Kaidu River basin runoff simulation runoff coefficient for rainfall time lag

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近场光存储及其研究进展

物理学进展 2002年第2期22卷 188-197页

作者：魏劲松张约品阮昊干福熹中国科学院上海光学精密机械研究所上海201800

本文从近场光学的超分辨原理出发详细介绍和分析了孔径探针型近场光存储技术、SIL透镜近场光存储技术和近场超分辨结构光盘存储技术等的基本原理。

关键词： SIL透镜 Supr-RENS 光存储近场光学光盘存储信息存储超分辨原理

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激光自混合干涉仪的实验研究

中国激光 2001年第1期28卷 29-32页

作者：马军山王向朝方祖捷强锡富中国科学院上海光机所上海201800 哈尔滨工业大学哈尔滨150001

分析了激光自混合干涉仪位移测量误差及特点 ,提出了干涉仪的设计原则。对激光自混合干涉仪的系统稳定性与测量分辨力进行了实验研究 ,给出了改善系统稳定性与测量分辨力的有效方法。

关键词：自混合干涉仪半导体激光器位移测量误差

CD-R光盘盘基槽深和槽宽均匀性测试方法研究

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中国激光 2001年第11期28卷 994-998页

作者：徐文东干福熹施宏仁何红林强中国科学院上海光机所上海201800

介绍了一种利用衍射方法测试CD R光盘盘基槽深和槽宽均匀性的方法。CD R光盘盘基槽深和槽宽均匀性的测试对于CD R光盘的制造非常重要 ,它可反映出母盘涂胶、刻录、显影、金属化、电铸及盘基复制的质量。尽管它不能精确测试沟槽的形状 ,... 详细信息

介绍了一种利用衍射方法测试CD R光盘盘基槽深和槽宽均匀性的方法。CD R光盘盘基槽深和槽宽均匀性的测试对于CD R光盘的制造非常重要 ,它可反映出母盘涂胶、刻录、显影、金属化、电铸及盘基复制的质量。尽管它不能精确测试沟槽的形状 ,但在测试均匀性时却显得简单、可靠、灵敏、快速和无损。

关键词： CD-R光盘盘基光栅衍射槽深槽宽测试

150ns长脉宽XeCl准分子激光器的研究

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中国激光 1997年第4期24卷 297-301页

作者：谷怀民赵震声匡梅奚居雄胡雪金中国科学院安徽光机所

通过采用多级Ｌ－Ｃ峰化回路、增大输出镜反射率、改变ＨＣｌ浓度的方法，使ＸｅＣｌ准分子激光的脉冲宽度达到１５０ｎｓ以上（最大脉宽达１７５ｎｓ），单脉冲能量大于１２０ｍＪ。同时对紫外准分子激光的光纤耦合系统进行了研究，直... 详细信息

通过采用多级Ｌ－Ｃ峰化回路、增大输出镜反射率、改变ＨＣｌ浓度的方法，使ＸｅＣｌ准分子激光的脉冲宽度达到１５０ｎｓ以上（最大脉宽达１７５ｎｓ），单脉冲能量大于１２０ｍＪ。同时对紫外准分子激光的光纤耦合系统进行了研究，直径为０．４，０．６，０．８，１．５ｍｍ的紫外石英光纤的耦合输出能量分别为１０，２９，３９。

关键词：长脉宽光纤耦合准分子激光器