检索结果-内蒙古大学图书馆

Research on the cascaded fiber F-P cavity fabricated by femtosecond laser with FBG and its sensing characterization

Yi Qi Yi Biao Xue Bao/Chinese Journal of Scientific Instrument 2017年第9期38卷 2193-2199页

作者： Zhang, Wen Meng, Fanyong Song, Yanming Lou, Xiaoping Zhu, Lianqing Beijing Engineering Research Center of Optoelectronic Information and Instruments Beijing Information Science and Technology University Beijing100016 China Key Laboratory of Modern Measurement Control Technology Ministry of Education Beijing100192 China Beijing Key Laboratory of Optoelectronic Test Technology Beijing Information Science and Technology University Beijing100192 China

A cascaded fiber Fabry-Perot (F-P) cavity fabricated by femtosecond laser with fiber Bragg grating (FBG) and its sensing characterization has been proposed and its temperature and strain sensing characterization has been studied. During two hours of stability test, the maximum FBG wavelength shift is 0.009 nm, and the maximum FBG power drift is 0.015 dB;the maximum F-P cavity wavelength shift is 0.018 nm, and the maximum F-P cavity power drift is 0.072 dB. When the strain is varying from 0 μΕ to 450 μΕ then back to 0 μΕ, the FBG wavelength peak is shifting towards right then left with the wavelength shift 0.530 4 nm, and the strain sensitivity is 1.17 pm/μΕ with linearity higher than 0.99;the F-P cavity wavelength shift 0.4911nm, and the strain sensitivity is 1.10 pm/μΕ with linearity higher than 0.90. When the temperature is varying from 50℃ to 200℃ then back to 50℃, the FBG wavelength peak is shifting towards right then left with the wavelength shift 1.418nm, and the temperature sensitivity is 10.09 pm/℃ with linearity higher than 0.95;the F-P cavity wavelength shift 1.578 nm, and the strain sensitivity is 10.53 pm/℃ with linearity higher than 0.98. This paper provides not only effective method to solve the problem of single fiber for double parameter measurement, but also reference value for the measurement of multi parameters coupling and decoupling in complex environment. © 2017, Science Press. All right reserved.

关键词： Fiber Bragg gratings

来源：评论

学校读者我要写书评

暂无评论

1178 J,527 nm near diffraction limited laser based on a complete closed-loop adaptive optics controlled off-axis multi-pass amplification laser system

引用

High Power Laser Science and Engineering 2021年第2期9卷 149-160页

作者： Deen Wang Xin Zhang Wanjun Dai Ying Yang Xuewei Deng Lin Chen Xudong Xie Dongxia Hu Feng Jing Zeping Yang Qiang Yuan Xiaofeng Wei Qihua Zhu Wanguo Zheng Xiaomin Zhang Lei Huang Key Laboratory of Photonic Control Technology(Tsinghua University) Ministry of EducationBeijing 100084China State Key Laboratory of Precision Measurement Technology and Instruments Department of Precision InstrumentTsinghua UniversityBeijing 100084China Research Center of Laser Fusion CAEPMianyang 621900China Institute of Optics and Electronics Chinese Academy of SciencesChengdu 610209China

A 1178 J near diffraction limited 527 nm laser is realized in a complete closed-loop adaptive optics(AO)controlled off-axis multi-pass amplification laser *** from a fiber laser and amplified by the pre-amplifier and the main amplifier,a 1053 nm laser beam with the energy of 1900 J is obtained and converted into a 527 nm laser beam by a KDP crystal with 62%conversion efficiency,1178 J and beam quality of 7.93 times the diffraction limit(DL).By using a complete closed-loop AO configuration,the static and dynamic wavefront distortions of the laser system are measured and *** correction,the diameter of the circle enclosing 80%energy is improved remarkably from 7.93DL to *** focal spot is highly concentrated and the 1178 J,527 nm near diffraction limited laser is achieved.

关键词： kilojoule near diffraction limit 527 nm X-ray

来源：评论

学校读者我要写书评

暂无评论

Guided mode meta-optics: Metasurface-dressed nanophotonic waveguides for arbitrary designer mode couplers and on-chip OAM emitters with configurable topological charge

arXiv

引用

arXiv 2021年

作者： Meng, Yuan He, Tiantian Liu, Zhoutian Hu, Futai Xiao, Qirong Liu, Qiang Gong, Mali State Key Laboratory of Precision Measurement Technology and Instruments Tsinghua University Beijing100084 China Key Laboratory of Photonic Control Technology Ministry of Education Tsinghua University Beijing100084 China

Metasurfaces have achieved fruitful results in tailoring complexing light fields in free space. However, a systematic investigation on applying the concept of meta-optics to completely control waveguide modes is still elusive. Here we present a comprehensive catalog capable of selectively and exclusively excite almost arbitrary high-order waveguide modes of interest, leveraging silicon metasurface-patterned silicon nitride waveguides. By simultaneously engineering the phase-matched gradient of the metasurface and the vectorial spatial modal overlap between the nanoantenna near-field and target waveguide mode for excitation, either single or multiple high-order modes are successfully launched with high purity reaching 98% and broad bandwidth. Moreover, on-chip twisted light generators are also theoretically demonstrated with configurable OAM topological charge from -3 to +2, serving as a comprehensive framework for metasurface-enabled guided mode optics and motivating further applications such as versatile integrated couplers, demultiplexers, and mode-division multiplexing-based communication systems. © 2021, CC BY.

关键词： Guided electromagnetic wave propagation

来源：评论

学校读者我要写书评

暂无评论

One-Shot Three-Dimensional measurement Based on Spectral Interferometry Using a Digital Micromirror Device

One-Shot Three-Dimensional Measurement Based on Spectral Int...

引用

Pacific Rim Conference on Lasers and Electro-Optics (CLEO/Pacific Rim)

作者： Jinxu Zhang Liheng Shi Yingying Gu Donglai Zhang Lu Yin Guanhao Wu Department of Precision Instrument State Key Laboratory of Precision Measurement Technology and Instruments Tsinghua University Beijing China Space Optoelectronic Measurement and Perception Lab. Beijing Institute of Control Engineering Beijing China National Key Laboratory of Space Intelligent Control China Academy of Space Technology Beijing China

We present a one-shot 3D spectral interferometry technique using a digital micromirror device. By encoding the distribution of the spatial light field, this approach enables 3D imaging of step structures within 27 ms.

ISBN: (数字)9798350372076

ISBN: (纸本)9798350372083

关键词： Optical interferometry Three-dimensional displays Imaging Surface emitting lasers measurement by laser beam Encoding Microcavities

来源：评论

学校读者我要写书评

暂无评论

Optical fiber sensor by cascading long period fiber grating with FBG for double parameters measurement

引用

Optoelectronics Letters 2017年第5期13卷 372-375页

作者： Zhang, Wen Lou, Xiao-ping Dong, Ming-li Zhu, Lian-qing Beijing Engineering Research Center of Optoelectronic Information and Instruments Beijing Information Science and Technology University Beijing China Key Laboratory of Modern Measurement Control Technology Ministry of Education Beijing Key Laboratory for Optoelectronics Measurement Technology Beijing Information Science and Technology University Beijing China Beijing Key Laboratory of Optoelectronic Test Technology Beijing Information Science and Technology University Beijing China

An optical fiber sensor for strain and temperature measurement based on long period fiber grating (LPFG) cascaded with fiber Bragg grating (FBG) structure has been proposed and realized both theoretically and experimentally. Theoretical analysis shows that two microstructures with similar sensitivities cannot be used for double parameters measurement. The LPFG is micromachined by the CO2 laser, and the FBG is micromachined by the excimer laser. For the validation and comparison, two FBGs and one LPFG are cascaded with three transmission valleys, namely FBG1 valley at 1 536.3 nm, LPFG valley at 1 551.2 nm, and FBG2 valley at 1 577.3 nm. The temperature and strain characteristics of the proposed sensor are measured at 45—70 °C and 250—500 με, respectively. The sensitivity matrix is determined by analyzing wavelength shifts and parameter response characterization of three different dips. The proposed optical fiber sensor based on LPFG cascaded with FBG structure can be efficiently used for double parameters measurement with promising application prospect and great research reference value.

关键词：

来源：评论

学校读者我要写书评

暂无评论

3.3kw Narrow Linewidth Fbg-Based Mopa Configuration Fiber Laser with Near-Diffraction-Limited Beam Quality

SSRN

引用

SSRN 2022年

作者： Du, Shanshan Fu, Guohao Qi, Tiancheng Li, Chao Huang, Zhihua Li, Dan Yan, Ping Gong, Mali Xiao, Qirong Ministry of Education Key Laboratory of Photonics Control Technology Department of Precision Instruments Tsinghua University Beijing100084 China State Key Laboratory of Precision Measurement Technology and Instruments Department of Precision Instruments Tsinghua University Beijing100084 China Wuhan Guangzhi Technology Co. Ltd. Hubei Wuhan430040 China

This paper demonstrates a narrow-linewidth fiber laser with near-diffraction-limited beam quality and high Raman suppression ratio by utilizing Master Oscillator Power-Amplifier structure based on narrow-bandwidth fiber Bragg gratings. The output power reaches 3.31 kW with a slope efficiency of 85.0%. At the maximum output power, the 3 dB, 10 dB, and 20 dB linewidths are 0.40 nm, 1.20 nm, and 3.09 nm, respectively. The beam quality M2 factor is 1.32 and the Raman suppression ratio reaches 26.3 dB. A pair of narrow-bandwidth fiber gratings were used in the oscillator to compress the linewidth of the seed laser. We used backward-pumping configuration and plume-coiled gain fiber in the amplification stage to suppress the Raman effect and select transverse mode by fiber-bending. Finally, a compact all-fiber laser was obtained with narrow-linewidth, high beam quality, and effective suppression of the Raman effect. To the best of our knowledge, this is the highest output power for a sub-nanometer-linewidth laser using narrow-bandwidth fiber gratings and none-wavelength-locked laser diodes, which achieves near-diffraction-limit beam quality. This provides a solution for high-power narrow-linewidth laser sources with high beam quality. © 2022, The Authors. All rights reserved.

关键词： Diffraction

来源：评论

学校读者我要写书评

暂无评论

Intelligent optoelectronic processor for orbital angular momentum spectrum measurement

arXiv

引用

arXiv 2022年

作者： Wang, Hao Zhan, Ziyu Hu, Futai Meng, Yuan Liu, Zeqi Fu, Xing Liu, Qiang Tsinghua University State Key Laboratory of Precision Measurement of Technology and Instruments Department of Precision Instrument Beijing100084 China Key Laboratory of Photonic Control Technology Ministry of Education Beijing100084 China

Orbital angular momentum (OAM) detection underpins almost all aspects of vortex beams’ advances such as communication and quantum analogy. Conventional schemes are frustrated by low speed, complicated system, limited detection range. Here, we devise an intelligent processor composed of photonic and electronic neurons for OAM spectrum measurement in a fast, accurate and direct manner. Specifically, optical layers extract invisible topological charge information from incoming light and a shallow electronic layer predicts the exact spectrum. The integration of optical-computing promises us a compact single-shot system with high speed and energy efficiency (optical operations / electronic operations ~103), neither necessitating reference wave nor repetitive steps. Importantly, our processor is endowed with salient generalization ability and robustness against diverse structured light and adverse effects (mean squared error ~10−5 ). We further raise a universal model interpretation paradigm to reveal the underlying physical mechanisms in the hybrid processor, as distinct from conventional ‘black-box’ networks. Such interpretation algorithm can improve the detection efficiency up to 25-fold. We also complete the theory of optoelectronic network enabling its efficient training. This work not only contributes to the explorations on OAM physics and applications, and also broadly inspires the advanced links between intelligent computing and physical effects. Copyright © 2022, The Authors. All rights reserved.

关键词： Mean square error

来源：评论

学校读者我要写书评

暂无评论

Divergence-degenerate spatial multiplexing towards higher-dimensional optical communications

Divergence-degenerate spatial multiplexing towards higher-di...

引用

Conference on Lasers and Electro-Optics (CLEO)

作者： Zhensong Wan Yijie Shen Xing Fu Ministry of Education Key Laboratory of Photonic Control Technology (Tsinghua University) Beijing China Department of Precision Instrument State Key Laboratory of Precision Measurement Technology and Instruments Tsinghua University Beijing China

We demonstrate a novel modal basis set with highly consistent propagation dynamics, having a divergence variation by merely 18% among 100 lowest order modes, which provides two orders of magnitude larger channels than... 详细信息

ISBN: (数字)9781957171050

ISBN: (纸本)9781665466660

关键词： Lasers and electrooptics Laser modes Orbits Optical fiber communication Space division multiplexing Electrooptical waveguides

来源：评论

学校读者我要写书评

暂无评论

Combination of high order polarization vortex beams using Hermite–Gauss beams

引用

Optical and Quantum Electronics 2018年第4期50卷 1-11页

作者： Jing-tao Xin Ming-li Dong Xiao-ping Lou Lian-qing Zhu Beijing Engineering Research Center of Optoelectronic Information and Instruments Beijing Information Science and Technology University Beijing China Key Laboratory of Modern Measurement Control Technology Ministry of Education Beijing China Beijing Key Laboratory of Optoelectronic Test Technology Beijing Information Science and Technology University Beijing China

A method to combine arbitrary order polarization vortex beams (PVBs) by Hermite–Gauss mode beams with designed field distributions is proposed. The orders of PVBs are determined by the modes of HG beams which are used in the combination scheme and the intensity distributions are the same as those of Laguerre–Gaussian beams. Simulations and experiments were also demonstrated, which verifies the feasibility of the proposed method.

关键词：

来源：评论

学校读者我要写书评

暂无评论

Traffic Vibration Localizing and Analyzing Using Urban Fiber Network

Traffic Vibration Localizing and Analyzing Using Urban Fiber...

引用

Conference on Lasers and Electro-Optics (CLEO)

作者： Guan Wang Zhongwang Pang Fangmin Wang Yufeng Chen Hongfei Dai Bo Wang Department of Precision Instrument State Key Laboratory of Precision Measurement Technology and Instruments Tsinghua University Beijing China Key Laboratory of Photonic Control Technology (Tsinghua University) Ministry of Education Beijing China

Urban fiber cable is explored as a sensing network to monitor the traffic flow on Beijing Ring Road. Different traffic patterns (including 2022 Winter Olympics) of heavy and light vehicles are observed and analyzed.

ISBN: (纸本)9781957171258

关键词： Cameras Fiber networks Laser interferometry Sensors Vibration

来源：评论

学校读者我要写书评

暂无评论

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案：

请选择收藏分类：

通借通还

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：