共查询到20条相似文献,搜索用时 187 毫秒
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基于二次内反射的光可变衰减器的研究 总被引:1,自引:1,他引:0
利用双面金属包覆波导激发的高阶导模提出一种快速响应的聚合物电光可变光衰减器(VOA).与传统的聚合物波导VOA相比,文中设计的可变光衰减器的显著特点是同一入射光束在波导中能够实现二次衰减全反射.理论与实验表明,该VOA器件具有动态范围大、驱动电压低、响应时间极快、插入损耗小、器件稳定性好以及制备工艺简单等诸多特点. 相似文献
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金属膜衬底上亚波长介质光栅结构的特性及传感应用 总被引:3,自引:0,他引:3
提出亚波长介质光栅-金属膜-石英玻璃衬底结构,根据等效介质理论该结构可等效为由金属-光栅-包覆层构成的单面金属包覆波导,在入射波长和入射角满足一定条件时,发生导模共振(GMR)从而产生光波全吸收现象。根据严格耦合波分析(RCWA)理论进行数值分析发现,等效波导中的TM1 GMR峰尖锐,并且对光栅包覆层的折射率变化非常敏感,角度灵敏度为127.87°/RIU(RIU为折射率单位),波长灵敏度为409.35 nm/RIU,在很大的折射率范围内线性度良好。与全介质GMR传感器和光栅型表面等离子体共振(SPR)传感器相比,该结构通过GMR实现较高灵敏度的同时,其较窄的共振峰使得检测精度更高。 相似文献
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基于单侧几何形变结构的全光纤Michelson干涉高温传感器 总被引:1,自引:1,他引:0
利用CO2激光脉冲对标准单模光纤(SMF)单向形成较小的几何形变,把部分基模能量耦合到光纤包层,制作了一种新型的在线型Michelson干涉传感器。理论分析了这种几何微扰激发的包层模特性,并利用芯模-包层模较大的热光系数差,把这种传感器应用于高温测量。实验结果表明,这种干涉传感器的温度灵敏度为0.093 7nm/℃,并且在800℃温度范围内具有良好的线性和重复性。这种制作简单、结构稳定、体积小和灵敏度高的全光纤在线型Michelson温度传感器将具有较大的潜在应用价值。 相似文献
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基于古斯汉欣效应的皮米级位移传感器的实验研究 总被引:1,自引:0,他引:1
本文利用光束在对称双面金属包覆波导表面反射时古斯一汉欣(Goos—Hanchen)位移具有极大的增强效应,提出一种灵敏度的极高的新型位移传感器。与传统的光强传感器相比,这种传感器消除了光源的能量波动对灵敏度的影响,从而能够观测更加微小的位移变化。在实验上实现了8pm微小位移传感。研究表明,该器件测量实时性强、精确度较高... 相似文献
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Lin Chen Zhuangqi Cao Qishun Shen Xiaoxu Deng Fang Ou Yaojun Feng 《Lightwave Technology, Journal of》2007,25(2):539-543
The ultrahigh order modes of a symmetrical metal-cladding optical waveguide, which exhibit strong wavelength dispersion characteristics, are used to track small wavelength changes of the light output of laser diodes. In the case of free-space coupling, the wavelength shift is transformed into an intensity variation of the light reflected on a surface of the waveguide. The sensitivity considering the divergence of the incident light and the thickness of the upper cladding is analyzed. A wavelength resolution of 0.5 pm at a center wavelength of 859.8 nm is demonstrated experimentally 相似文献
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Sofyan A. Taya Eman J. El-Farram Taher M. El-Agez 《AEUE-International Journal of Electronics and Communications》2012,66(3):204-210
The present paper deals with three-layer planar waveguide optical sensor. Different from the conventional slab waveguide sensors in which the effective refractive index of the propagating mode is taken to be the probe for detection changes in the analyte refractive index, we adopt Goos-Hänchen (GH) shift as the sensing probe for the proposed sensor. We show that the GH shift is strongly dependent on the refractive index of the cladding, thus it is a good candidate for detection changes in the analyte refractive index. We present and study the sensitivity of the GH shift at the cladding-film and substrate-film interfaces. It is found that GH shift has a high sensitivity and can be used for versatile optical slab waveguide sensors. 相似文献
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Optical voltage sensor based on electrooptic crystal multiplier 总被引:3,自引:0,他引:3
A novel optical voltage sensor based on the electrooptic crystal multiplier is proposed and experimentally investigated. Different from the conventional bulk-type optical voltage sensor, the optical sensing unit is simply composed of an electrooptic crystal and two polarizers and does not need quarter wave-plate. By using different modulation approaches, both ac and dc voltages can be measured with controllable sensitivity and measurement range. The effective value of ac voltage can also be measured with nonmodulation approach. The dc voltage from 0.1 to 120 V and 50 Hz ac voltage from 0.05 to 100 V have been measured with good linearity. The potential applications of the proposed voltage sensor include the low voltage measurement in the field of electromagnetic compatibility and the high voltage measurement in electric power industry. 相似文献
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Kageyama K. Murayama H. Uzawa K. Ohsawa I. Kanai M. Akematsu Y. Nagata K. Ogawa T. 《Lightwave Technology, Journal of》2006,24(4):1768-1775
New principle and a geometrical arrangement of an optical fiber for a vibration/acoustic measurement are proposed in the present paper. The sensor is based on a new finding that a frequency of light wave transmitted through a bent optical fiber is shifted by vibration at the bent region. The phenomenon can be explained as Doppler's effect in flexible and expandable light waveguide. Several configurations of the sensor have been designed, and very high sensitivity is achieved in the extremely wide frequency range. Principle, sensor configuration and theoretical sensitivity, measurement system, and some experimental consideration are described in the present paper. The sensor sensitivity was examined experimentally in the low and middle frequency range, and the detectability was confirmed experimentally in the frequency range of acoustic emission signals. 相似文献
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近年来,高精度的位移测量精度要求越来越高,为响应这一需求,本文依据待测位移量可由反射光强变化得出的原理设计了一种基于塑料光纤的位移传感器.本文所涉及的光纤位移传感器以静态拉伸式杨氏模量测量实验中钢丝长度的微小变化为待测量进行设计.在整个传感器系统制作完成后,结果显示,在0~3mm的位移范围内,测量输出与实际位移成线性关系且线性度为0.6%,在较大位移区间内实现了具有良好线性度的测量,同时,根据实验结果测得灵敏度为2.13mV/μm,保证了测量的精准度.这种设计方法的使用扩大了塑料光纤的应用领域,同时,优化了传感器的精准度和线性化精度等性能指标. 相似文献
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为了精密控制激光光束的平行移动,利用双面金属包覆波导结构在导波共振激发时对古斯-汉欣(Goos-Hänchen)位移的增强效应,采用光学非线性晶体材料作为波导的导波层,通过在波导中两层金属膜间加入控制电压,改变波导参量,实现反射光侧向位移的电调谐,得到了720μm范围内的光束平移电控,控制精度可达25nm。结果表明,实验结果和理论模拟吻合较好。预计本工作对光学微加工领域应用具有积极而广泛的意义。 相似文献
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为了寻找到性能更好、灵敏度更高的光波导传感器,在传统反谐振反射光波导结构的基础之上,提出了一种新型反谐振反射光波导传感器,对其反射率和传输损耗进行了模拟,并计算了它的灵敏度.结果表明,与传统表面均匀传感型反谐振反射光波导传感器相比,新型传感器直接将待测的样品作为波导层并且采用了周期结构的反共振层,使大部分光束集中在样品中传播,从而降低了传输损耗,提高了传感器的灵敏度,为波导传感器的制作提供了一定的数值参考. 相似文献
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Jin Hwa Ryu Woo‐Jin Lee Bong Kuk Lee Lee‐Mi Do Kang Bok Lee Namkyoung Um Kyu‐Ha Baek 《ETRI Journal》2014,36(5):841-846
This study proposes a novel optical sensor structure based on a refractometer combining a bend waveguide with an air trench. The optical sensor is a splitter structure with a reference channel and a sensing channel. The reference channel has a straight waveguide. The sensing channel consists of a U‐bend waveguide connecting four C‐bends, and a trench structure to partially expose the core layer. The U‐bend waveguide consists of one C‐bend with the maximum optical loss and three C‐bends with minimum losses. A trench provides a quantitative measurement environment and is aligned with the sidewall of the C‐bend having the maximum loss. The intensity of the output power depends on the change in the refractive index of the measured material. The insertion loss of the proposed optical sensor changes from 3.7 dB to 59.1 dB when the refractive index changes from 1.3852 to 1.4452. 相似文献