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Chinese Optics Letters 2019年第4期17卷 66-70页

作者： Aichen Ge Bowen Liu Wei Chen Haochen Tian Youjian Song Lu Chai Mingiie Hu Ultrafast Laser Laboratory School of Precision Instrument and Optoelectronics Engineering Key Laboratory of Optoelectronic Information Technology (Ministry of Education) Tianjin University

We demonstrate a coherent synthesis system based on femtosecond Yb-doped fiber laser technology. The output pulse of the amplification system is divided into two replicas and seeded into photonic crystal fibers of two parallel branches for nonlinear pulse compression. Because of the different nonlinear dynamics in the photonic crystal fibers, the compressed pulses show different spectra, which can be spliced to form a broad coherent spectrum. The integrated timing jitter between the pulses of two branches is less than one tenth of an optical *** coherently synthesizing pulses from these two branches, 8 fs few-cycle pulses are produced.

关键词： demonstrate a coherent femtosecond Yb-doped coherently synthesizing

Anti-Stokes Frequency Shift and Evolution in Polarization-Maintaining Photonic Crystal Fiber with Two-Zero Dispersion Wavelengths

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Chinese Physics Letters 2009年第8期26卷 132-135页

作者：王河林冷雨欣徐至展祁义红胡明列王清月 State Key Laboratory of High Field Laser Physics Shanghai Institute of Optics and Fine Mechanics Chinese Academy of Sciences Shanghai 201800 Ultrafast laser Laboratory Key Laboratory of Optoelectronic Information and Technical Science College of Precision Instrument and Optoelectronic Engineering Tianjin University Tianjin 300072

Using the tunable pump pulses with about lOO fs pulse duration and 1064 nm central wavelength; the polarization-, wavelength- and power-dependent anti-Stokes lines are generated and modulated simultaneously in a polarization-maintaining photonie crystal fiber （PM-PCF） with two zero-dispersion wavelengths. By accurately controlling the polarization directions, the wavelength and the power of the pump pulse in the fiber anomalous region close to the second zero-dispersion wavelength of the PM-PCF, the output anti-Stokes pulse spectra can be tuned between 563 nm and 603 nm, which is in good agreement with the theoretical simulation. The color conversion of the mode image from yellow to orange is also observed with the different polarization pump pulses. These results can be attributed to the combined interaction between the fiber birefringence （including linear- and nonlinear- birefringence） and dispersion, and are attributed to phase-matching parametric four-wave mixing.

关键词： STOKES equations DOPPLER effect OPTICAL polarization CRYSTAL whiskers DISPERSION WAVELENGTHS OPTICAL pumping MODULATION (Electronics) SPECTRUM analysis

Design of a control system with high stability for a streak camera using isolated ADC

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Nuclear Science and Techniques 2018年第2期29卷 57-67页

作者： Yu-Man Fang Xiang-Yan Xu Jin-Shou Tian Cheng-Quan Pei Key Laboratory of Ultra-Fast Photoelectric Diagnostics Technology Xi’an Institute of Optics and Precision MechanicsXi’an 710119ShaanxiChina University of Chinese Academy of Sciences Beijing 100049China Xi'an Jiaotong University Xi’an 710049ShaanxiChina

The streak camera is an ultra-fast diagnostic instrument with high sensitivity, and a high temporal and spatial resolution. It is primarily employed in various scientific research, such as inertial confinement fusion(ICF),synchrotron light sources, and electron–positron *** automatic control system for an X-ray streak camera is presented in this paper. The output terminal of an analogto-digital converter was isolated from its input terminal, to reduce interference from high-voltage electrodes. Compared with traditional methods, this scheme also improved the internal electromagnetic interface immunity. Therefore,the system stability was enhanced. With this optimized control system, some characterizations of the streak camera were measured. Static and dynamic spatial resolutions of 25 and 20 lp/mm(CTF = 20%), respectively, were obtained. In addition, a dynamic range of 552:1 and a temporal resolution of 7.3 ps were achieved. The results confirmed that these characterizations are sufficient for the specifications derived from the diagnostic requirements of ICF.

关键词： ICF Distributed control Streak camera Isolated ADC X-ray detector

Characterizing the oil and water distribution in low permeability core by reconstruction of terahertz images

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Science China(Physics,mechanics & Astronomy) 2016年第6期59卷 89-90页

作者： Ri Ma Bao Xin Yang Miao Cheng Jing Feng Ying Zhi Zhang Hong Lei Zhan Kun Zhao Mao Rong Wang Jian Quan Yao Beijing Key Laboratory of Optical Detection Technology for Oil and Gas China University of Petroleum Beijing 102249 China Qingxin Oil Field Development Company Limited Anda 151400 China College of precision instrument and Opto-electronics Engineering Tianjin University Tianjin 300072 China

Dear Editors,Exploitation of low permeability oilfield has become an interest of the world due to the decline of conventional oil *** has been observed to be able to enhance oil recovery in tight sandstone reservoir.

关键词：成像特征低渗透太赫兹岩心表征水

All-sky Guide Star Catalog for CSST

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Research in Astronomy and Astrophysics 2024年第4期24卷 35-59页

作者： Hui-Mei Feng Zi-Huang Cao Man I Lam Ran Li Hao Tian Da-Yi Yin Yuan-Yu Yang Xin Zhang Dong-Wei Fan Yi-Qiao Dong Xin-Feng Li Wei Wang Long Li Hugh RAJones Yi-Han Tao Jia-Lu Nie Pei-Pei Wang Mao-Yuan Liu He-jun Yang Chao Liu Key Laboratory of Cosmic Rays(Tibet University) Ministry of EducationLhasa 850000China Institute for Frontiers in Astronomy and Astrophysics Beijing Normal UniversityBeijing 102206China National Astronomical Observatories Chinese Academy of SciencesBeijing 100101China University of ChineseAcademy of Sciences Beijing 100049China Shanghai Institute of Technical Physics Chinese Academy of SciencesShanghai200083China Technology and Engineering Center for Space Utilization.Chinese Academy of Sciences Beijing 100094China Changchun Institute of Optics Fine Mechanics and PhysicsChinese Academy of SciencesChangchun 130033China Centre for Astrophysics University of HertfordshireHatfieldUK Beijing University of Technology Beijing 100124China

The China Space Station Telescope(CSST)is a two-meter space telescope with multiple back-end *** Fine Guidance Sensor(FGS)is an essential subsystem of the CSST precision Image Stability System to ensure the required absolute pointing accuracy and line-of-sight *** this study,we construct the Main Guide Star Catalog for *** accomplish this,we utilize the information about the FGS and object information from the Gaia Data Release *** provide an FGS instrument magnitude and exclude variables,binaries,and high proper motion stars from the catalog to ensure uniform FGS guidance ***,we generate a HEALPix index,which provides a hierarchical tessellation of the celestial sphere,and employ the Voronoi algorithm to achieve a homogeneous distribution of stars across the *** distribution ensures adequate coverage and sampling of the *** performance of the CSST guide star catalog was assessed by simulating the field of view of the FGS according to the CSST mock survey strategy *** analysis of the results indicates that this catalog provides adequate coverage and *** catalog's performance meets the FGS requirements,ensuring the functioning of the FGS and its guidance capabilities.

关键词： catalogs astrometry instrumentation:detectors

First observation of tropospheric nitrogen dioxide from the Environmental Trace Gases Monitoring instrument onboard the GaoFen-5 satellite

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Light(Science & Applications) 2020年第1期9卷 1389-1397页

作者： Chengxin Zhang Cheng Liu Ka Lok Chan Qihou Hu Haoran Liu Bo Li Chengzhi Xing Wei Tan Haijin Zhou Fuqi Si Jianguo Liu School of Earth and Space Sciences University of Science and Technology of ChinaHefei 230026China Department of precision Machinery and precision instrumentation University of Science and Technology of ChinaHefei 230026China Key Laboratory of Environmental Optics and Technology Anhui Institute of Optics and Fine MechanicsChinese Academy of SciencesHefei 230031China Center for Excellence in Regional Atmospheric Environment Institute of Urban EnvironmentChinese Academy of SciencesXiamen 361021China Key Laboratory of precision Scientific instrumentation of Anhui Higher Education Institutes University of Science and Technology of ChinaHefei 230026China Remote Sensing Technology Institute(IMF) German Aerospace Center(DLR)OberpfaffenhofenGermany

The Environmental Trace Gases Monitoring instrument(EMI)is the first Chinese satellite-borne UV–Vis spectrometer aiming to measure the distribution of atmospheric trace gases on a global *** EMI instrument onboard the GaoFen-5 satellite was launched on 9 May *** this paper,we present the tropospheric nitrogen dioxide(NO2)vertical column density(VCD)retrieval algorithm dedicated to EMI *** report the first successful retrieval of tropospheric NO_(2) VCD from the EMI *** retrieval improved the original EMI NO_(2) prototype algorithm by modifying the settings of the spectral fit and air mass factor calculations to account for the on-orbit instrumental performance *** retrieved EMI NO_(2) VCDs generally show good spatiotemporal agreement with the satellite-borne Ozone Monitoring instrument and TROPOspheric Monitoring instrument(correlation coefficient R of ~0.9,bias<50%).A comparison with ground-based MAX-DOAS(Multi-Axis Differential Optical Absorption Spectroscopy)observations also shows good correlation with an R of *** results indicate that the EMI NO_(2) retrieval algorithm derives reliable and precise results,and this algorithm can feasibly produce stable operational products that can contribute to global air pollution monitoring.

关键词： measurement dioxide satellite

Matching Investigation between instrument precision and Aiming Method

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Semiconductor Photonics and Technology 2002年第3期8卷 190-192页

作者： WANG Jin jiang, JIN Guang yong, JIN Su kun, YANG Zhi wen (Graduates dept., Changchun Institutes of Optics and Fine mechanics, Changchun 130022, CHN) Graduates dept. Changchun Institutes of Optics and Fin Mechanics Changchun 130022

In the course of using precise visual instrument, aiming precision is an important parameter to analyze the measurement error. Usually, instrument calibrated error is set down as measurement error. In the paper, the precision theory of TC2003 theodolite is analyzed and some aiming experiments is done for different width line. Then, the relations between the width of line and aiming precision are shown by different aiming methods of two superposition solid lines and one line clipped by double lines. Finally, an effective method to improve aiming precision is proposed which adopts the aiming method of one line clipped by double lines.

关键词： Aiming precision Matching Theodoite

A review of anomalous refractive and reflective metasurfaces

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Nanotechnology and precision Engineering 2022年第2期5卷 54-64页

作者： Siqi Liu Zhenyu Ma Jian Pei Qingbin Jiao Lin Yang Wei Zhang Hui Li Yuhang Li Yubo Zou Xin Tan Fine instrument and Equipment R&D Center Changchun Institute of OpticsFine Mechanics and PhysicsChinese Academy of SciencesJilin 130033China University of Chinese Academy of Sciences Beijing 100049China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China

Abnormal refraction and reflection refers to the phenomenon in which light does not follow its traditional laws of propagation and instead is subject to refraction and reflection at abnormal angles that satisfy a generalization of Snell’s *** can realize this phenomenon through appropriate selection of materials and structural design,and they have a wide range of potential applications in the military,communications,scientific,and biomedical *** paper summarizes the current state of research on abnormal refractive and reflective metasurfaces and their application *** discusses types of abnormal refractive and reflective metasurfaces based on their tuning modes(active and passive),their applications in different wavelength bands,and their future *** technical obstacles that arise with existing metasurface technology are summarized,and prospects for future development and applications of abnormal refractive and reflective metasurfaces are discussed.

关键词： Anomalous refraction and reflection Generalized Snell’s law Metasurface material Metalens

First Chinese ultraviolet-visible hyperspectral satellite instrument implicating global air quality during the COVID-19 pandemic in early 2020

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Light(Science & Applications) 2022年第2期11卷 242-253页

作者： Cheng Liu Qihou Hu Chengxin Zhang Congzi Xia Hao Yin Wenjing Su Xiaohan Wang Yizhou Xu Zhiguo Zhang Department of precision Machinery and precision instrumentation University of Science and Technology of China230026 HefeiChina Key Laboratory of Environmental Optics and Technology Anhui Institute of Optics and Fine MechanicsHefei Institutes of Physical ScienceChinese Academy of Sciences230031 HefeiChina Center for Excellence in Regional Atmospheric Environment Institute of Urban EnvironmentChinese Academy of Sciences361021 XiamenChina Key Laboratory of precision Scientific instrumentation of Anhui Higher Education Institutes University of Science and Technology of China230026 HefeiChina School of Earth and Space Sciences University of Science and Technology of China230026 HefeiChina Department of Environmental Science and Engineering University of Science and Technology of China230026 HefeiChina

In response to the COVID-19 pandemic,governments worldwide imposed lockdown measures in early 2020,resulting in notable reductions in air pollutant *** changes in air quality during the pandemic have been investigated in numerous studies via satellite ***,no relevant research has been gathered using Chinese satellite instruments,because the poor spectral quality makes it extremely difficult to retrieve data from the spectra of the Environmental Trace Gases Monitoring instrument(EMI),the first Chinese satellite-based ultraviolet–visible spectrometer monitoring air ***,through a series of remote sensing algorithm optimizations from spectral calibration to retrieval,we successfully retrieved global gaseous pollutants,such as nitrogen dioxide(NO2),sulfur dioxide(SO2),and formaldehyde(HCHO),from EMI during the *** abrupt drop in NO2 successfully captured the time for each city when effective measures were implemented to prevent the spread of the pandemic,for example,in January 2020 in Chinese cities,February in Seoul,and March in Tokyo and various cities across Europe and ***,significant decreases in HCHO in Wuhan,Shanghai,Guangzhou,and Seoul indicated that the majority of volatile organic compounds(VOCs)emissions were ***,the lack of evident reduction in Beijing and New Delhi suggested dominant natural sources of *** comparing the relative variation of NO2 to gross domestic product(GDP),we found that the COVID-19 pandemic had more influence on the secondary industry in China,while on the primary and tertiary industries in Korea and the countries across Europe and America.

关键词： ultraviolet visible dioxide

EXTRACTING MODAL PARAMETERS FROM STRUCTURES UNDERGOING AMBIENT EXCITATION

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Journal of Shanghai Jiaotong university(Science) 2001年第2期6卷 117-122页

作者：华宏星陈之炎傅志方李中付宋汉文 Shanghai Jiaotong Univ. dept. of mechanics Eng. Science Fudan Univ.

On Line Parameter Identification Technique (OLPIT) was presented according to ambient excitation characteristics and the response cross-correlation function that is a sum of decaying sinusoids of the same form as the impulse response function of the original system. OLPIT is a new method of identification modal parameters from response of structures under ambient excitation. OLPIT is different from NExT (natural excitation technique) based on ITD method in four aspects: ① The algorithm is improved by the singular-value decomposition (SVD). ② Multi-value of b r in the Ibrahim Time Domain (ITD) is avoided. ③ OLPIT is used in both SIMO (single input, multi-output) and MIMO (multi input, multi-output). ④ The precision of modal parameter identificatioin is improved. The simulation studies demonstrate that the method is effective in identifying complex modes even with close frequencies and is robust to measurement noise.

关键词： ambient excitation modal analysis parameter identification random vibration