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Experimental research on dual polarized laser optical feedback microscope

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光学精密工程 2005年第5期13卷 613-619页

作者： MAO Wei ZHANG Shu-lian tan yi-dong State Key Laboratory of Precision Measurement Technology and Instruments Department of Precision Instruments Tsinghua University Beijing 100084 China

The principle of laser optical feedback microscope was presented and demonstrated. Three methods to advance the vertical resolution of laser optical feedback microscope were experimentally studied. The first one is to detect the two polarized lights’ intensities separately with a Wollaston prism instead of to detect the whole light’s intensity. The second is that both of the two orthogonally polarized lights of a birefringent dual frequency laser are fed back. The third one is that only one of the orthogonally polarized lights is fed back. The experimental results show that the modes competition between orthogonally polarized lights can be used to improve the vertical resolution of laser optical feedback microscope effectively.

关键词：激光光纤显微镜光学分析

Influence of Feedback Level on Laser Polarization in Polarized Optical Feedback

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Chinese Physics Letters 2013年第8期30卷 62-65页

作者： WU Yun tan yi-dong ZHANG Shu-Lian LI Yan The State Key Laboratory of Precision Measurement Technology and Instruments Department of Precision InstrumentsTsinghua UniversityBeijing 100084

The influence of feedback level(or the amplitude of feedback light)on laser polarization in polarized optical feedback is investigated.A polarizer is placed in the feedback cavity to form the polarized feedback,and an attenuator is placed in the feedback cavity to tune the feedback *** laser intensity and polarization vary dramatically at different transmissivities of the *** to the experimental phenomenon,the range of the attenuator transmissivity is divided into three zones:the flipping zone,monostable zone,and bistable *** the monostable zone,the laser polarization is always perpendicular to the axis of the polarizer in the feedback *** may provide an effective way to choose or control laser polarization.A theoretical model based on the self-consistency of laser oscillation is presented to analyze the experimental results.

关键词： polarization laser polarized

Real-Time Liquid Evaporation Rate Measurement Based on a Microchip Laser Feedback Interferometer

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Chinese Physics Letters 2013年第12期30卷 46-48页

作者： tan yi-dong ZHANG Song REN Zhou ZHANG Yong-Qin ZHANG Shu-Lian State Key Laboratory of Precision Measurement Technology and Instruments Department of Precision InstrumentsTsinghua UniversityBeijing 100084 School of Mechanical Engineering Nantong UniversityNantong 226019

We present a novel scheme to realize the direct real-time measurement of liquid evaporation rate and nanometer order liquid level *** is based on the phase measurement technology of Nd:YAG microchip laser frequency-shifted feedback,which not only has a high resolution and precision but also ultrahigh *** evaporation rates of four different transparent liquids and hot water are *** results indicate the ease and convenience of measuring and present promising application prospects in non-cooperative target measurement.

关键词： measurement Microchip transparent

Phase Tuning Characteristics of a Double-Longitudinal-Mode He-Ne Laser with Optical Feedback

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Chinese Physics Letters 2012年第9期29卷 80-83页

作者： ZENG Zhao-Li ZHANG Shu-Lian tan yi-dong CHEN Wen-Xue LI Yan The State Key Lab of Precision Measurement Technology and Instruments Department of Precision InstrumentsTsinghua UniversityBeijing 100084

The phase tuning characteristics of a double-longitudinal-mode He-Ne laser with optical feedback are *** phase behaviors of the two adjacent longitudinal modes are studied with different laser cavity lengths at the weak feedback level,and it is found that the phase difference of the two modes can be 0 to 180°along with the changing of the length of external *** high-density intensity fringes are obtained with asymmetric feedback cavity at a strong feedback *** particular,the phase difference is also observed between the two high-density fringes of adjacent modes,which have the potential to develop a direction sensitive laser feedback interferometer with high resolution.A simple theoretical analysis is presented,which fits well with the experimental results.

关键词： interferometer tuning cavity

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光回馈Nd:YAG激光器中的多模跳变现象

物理学报 2007年第4期56卷 2124-2130页

作者：谈宜东张书练清华大学精密测试技术及仪器国家重点实验室北京100084

研究了Nd:YAG激光器中光回馈引起的多模跳变现象.光回馈调制了激光器不同纵模的阈值增益,阈值增益最低的纵模获得振荡.在外腔调谐过程中,当振荡模式的阈值增益高于相邻模式的阈值增益时产生模跳变,光强调制曲线出现相应的波动.各跳变纵... 详细信息

研究了Nd:YAG激光器中光回馈引起的多模跳变现象.光回馈调制了激光器不同纵模的阈值增益,阈值增益最低的纵模获得振荡.在外腔调谐过程中,当振荡模式的阈值增益高于相邻模式的阈值增益时产生模跳变,光强调制曲线出现相应的波动.各跳变纵模在增益曲线上的位置不同,导致模跳变点位置不同,相应的光强调制曲线也不同.越靠近中心频率的纵模,其光强信号峰值越大,该纵模持续振荡时间也就越长.当两跳变纵模关于中心频率对称时,其光强信号峰值相等,纵模持续振荡时间也相等.

关键词：自混合干涉模跳变光回馈阈值增益

Induced pluripotent stem cell-related approaches to generate dopaminergic neurons for Parkinson's disease

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Neural Regeneration Research 2025年第11期20卷 3193-3206页

作者： Ling-Xiao yi Hui Ren Woon Genevieve Saw Li Zeng Eng King tan Zhi dong Zhou National Neuroscience Institute Singapore Nanyang Technology University Singapore Department of Neurology Singapore General HospitalSingapore Signature Research Program in Neuroscience and Behavioral Disorders Duke-NUS Medical SchoolSingapore

The progressive loss of dopaminergic neurons in affected patient brains is one of the pathological features of Parkinson's disease,the second most common human neurodegenerative *** the detailed pathogenesis accounting for dopaminergic neuron degeneration in Parkinson's disease is still unclear,the advancement of stem cell approaches has shown promise for Parkinson's disease research and *** induced pluripotent stem cells have been commonly used to generate dopaminergic neurons,which has provided valuable insights to improve our understanding of Parkinson's disease pathogenesis and contributed to anti-Parkinson's disease *** current review discusses the practical approaches and potential applications of induced pluripotent stem cell techniques for generating and differentiating dopaminergic neurons from induced pluripotent stem *** benefits of induced pluripotent stem cell-based research are *** dopaminergic neuron differentiation protocols from induced pluripotent stem cells are *** emerging three-dimension-based brain organoid models compared with conventional two-dimensional cell culture are ***,limitations,challenges,and future directions of induced pluripotent stem cell–based approaches are analyzed and proposed,which will be significant to the future application of induced pluripotent stem cell-related techniques for Parkinson's disease.

关键词： dopaminergic neurons induced pluripotent stem cells Parkinson's disease stem cell approaches

调频微片Nd:YAG激光器光回馈特性的研究

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物理学报 2007年第11期56卷 6408-6412页

作者：谈宜东张书练清华大学精密测试技术与仪器国家重点实验室北京100084

研究了调频微片Nd:YAG激光器的光回馈特性.在没有光回馈的情况下,激光频率每改变一个纵模间隔,激光器输出功率变化一个条纹.有光回馈时,同时改变激光频率和外腔相位,激光器输出功率波动频率正比于内、外腔长度之比.基于三镜腔等效模型... 详细信息

研究了调频微片Nd:YAG激光器的光回馈特性.在没有光回馈的情况下,激光频率每改变一个纵模间隔,激光器输出功率变化一个条纹.有光回馈时,同时改变激光频率和外腔相位,激光器输出功率波动频率正比于内、外腔长度之比.基于三镜腔等效模型的理论分析和实验结果相符合.并且讨论了这一现象在精密测量领域的潜在应用.

关键词：光回馈回馈条纹调频微片Nd:YAG激光器激光频率精密测量

激光回馈引起的微片Nd:YAG激光器频差调制

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物理学报 2014年第10期63卷 167-172页

作者：张松谈宜东张书练清华大学精密测试技术与仪器国家重点实验室北京100084

微片激光器由于自身的内应力会输出频率分裂的正交偏振的两个模式.研究了回馈对微片激光器频差的影响.研究发现:在回馈的作用下微片激光器的频差大小呈现出以初始频差为中心的类正弦的频差调制,周期为λ/2;频差调制曲线的幅度与回馈水... 详细信息

微片激光器由于自身的内应力会输出频率分裂的正交偏振的两个模式.研究了回馈对微片激光器频差的影响.研究发现:在回馈的作用下微片激光器的频差大小呈现出以初始频差为中心的类正弦的频差调制,周期为λ/2;频差调制曲线的幅度与回馈水平成正比,但是当回馈水平过强时会出现偏振态跳变,从而使频差消失;在一定的回馈外腔范围内,频差调制曲线的幅度与初始频差亦成正比.并利用复合腔模型和激光器的自洽理论进行了理论分析和模拟,所得结果与实验结果相符.此调制现象在精密测量领域有潜在应用.

关键词：光回馈微片激光器频差调制频率分裂

Force and impulse multi-sensor based on flexible gate dielectric field effect transistor

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International Journal of Minerals,Metallurgy and Materials 2025年第1期32卷 214-220页

作者： Chao tan Junling Lü Chunchi Zhang dong Liang Lei Yang Zegao Wang College of Materials Science and Engineering Sichuan UniversityChengdu 610065China The 54th Research Institute of China Electronics Technology Group Corporation Shijiazhuang 050081China

Nowadays,force sensors play an important role in industrial production,electronic information,medical health,and many other ***-dimensional material-based filed effect transistor(2D-FET)sensors are competitive with nano-level size,lower power consumption,and accurate ***,few of them has the capability of impulse detection which is a path function,expressing the cumulative effect of the force on the particle over a period of *** we fabricated the flexible polymethyl methacrylate(PMMA)gate dielectric MoS_(2)-FET for force and impulse sensor *** systematically investigated the responses of the sensor to constant force and varying forces,and achieved the conversion factors of the drain current signals(I_(ds))to the detected impulse(I).The applied force was detected and recorded by I_(ds)with a low power consumption of~30 *** sensitivity of the device can reach~8000%and the 4×1 sensor array is able to detect and locate the normal force applied on ***,there was almost no performance loss for the device as left in the air for two months.

关键词： flexible gate dielectric transistor force sensor impulse sensor force sensor array