共查询到19条相似文献,搜索用时 171 毫秒
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提出一种基于法布里—珀罗(Fabry Perot,F P)干涉的光纤倾角传感器,该传感器由单模光纤和毛细管组成。首先,分析光纤干涉原理和倾角传感原理;然后,制作封装光纤倾角传感器;最后,完成光纤F P传感器倾斜实验,通过对采集得到的数据分析得到传感器倾角的响应特性,并进行温度实验探究温度对传感器波长漂移的影响。实验结果表明:在0°~10°测量范围内,测量角度和反射波长呈线性关系,倾角灵敏度为02031nm/°,线性度为099707;在45~49℃温度范围内,温度灵敏度为4777nm/℃,线性度为099934。该传感器具有结构简单、成本低、灵敏度高等特点,具有广阔的应用前景。 相似文献
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利用光栅效应和保偏光纤的双折射效应相消原理, 设 计并制备了一种折射率不敏感温度 传感器。传感器由写在熊猫保偏光纤(PMF)上的倾角为45°的长周期光纤光栅(LPFG)对构 成。实验结果表明,当满足特定条件时随着环境折射率的变化,谐振波长零漂移;随 着环境温度的升高,谐振波长向长波方向漂移,温度灵敏度高达37p m/℃,高于报道的 螺旋型折射率调制级联光栅对(温度灵敏度为30pm/℃),三倍于Br agg光栅的温度灵 敏度(10pm/℃)。这种结构具有的折射率不敏感性,特别适用于生 产过程中液体的温度测量,而不必考虑折射率和温度的交叉敏感性。 相似文献
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Y型双声路声表面波质量传感器及其测量系统 总被引:7,自引:1,他引:7
报道了一种在128°Y切割X传播方向的LiNbO3基片上设计并研制新型的延迟线型声表面波质量传感器及测量系统。由于环境温度对声表面波质量传感器性能影响较大,因此采用新型的Y型双声路结构克服环境温度对传感器性能的影响。阐述了Y型双声路质量传感器器件的结构及设计、测试电路的原理,对实验结果作了分析讨论。测试结果表明:器件相对温度系数仅为11Hz/°C左右,器件的质量沉积效应灵敏度为3.62GHz·cm2/g,并且具有良好的线性度。 相似文献
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为了最大限度地提高无线射频识别(RFID)标签的操作距离,提出了一种集成于RFID标签芯片的超低功耗高精度CMOS温度传感器。传统的温度传感器主要采用带隙电路和ADC,而此类设计会消耗大量能量导致传感器功耗较高。提出传感器电路由新型数字环形振荡器,分频器,多路复用器和10位的数字计数器组成,温度转换成数字输出是在一个采样周期期间通获得过计数振荡器的时钟边缘数量得以实现。并且为了将温度灵敏度和动态范围最大化,使用的电源电压为0.3 v。振荡器的频率可以通过电容器组和堆叠晶体管进行数字修正。由于运用了阈值电压的温度依赖关系和MOS晶体管的载流子迁移率,因此与传统温度传感器相比,提出传感器的实现更加简单。通过0.18μm CMOS测试芯片获得的测量数据表明,提出的温度传感器分辨率为0.4°C/LSB,10位数字输出,校准后的可测量温度范围从-20°C到 95°C。采样频率为10Hz时,提出的传感器的功耗仅为92nW。 相似文献
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设计了一种由两个萨格纳克干涉仪(SI)级联组成的光纤温度传感器,并用实验证明了传感器在游标效应下的温度灵敏度放大特性。该传感器由两段不同长度的熊猫保偏光纤构成两个SI,然后两个SI旋转一个角度级联在一起组成一个温度传感装置,其中SI1用着温度传感,SI2用着参考。由于两个SI具有相近的自由光谱范围,级联时它们干涉谱叠加形成一个自由光谱范围很大的低频包络线。利用包络线漂移来考察温度变化,能够获得放大的灵敏度。实验结果显示级联后传感器的温度灵敏度为11.03 nm/℃,而单个SI1单独测量温度的灵敏度为-1.01 nm/℃。因此利用游标效应后,灵敏度增加了10.9倍,而且实验测量结果与理论计算结果基本吻合。 相似文献
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《Electron Devices, IEEE Transactions on》1987,34(12):2456-2462
A new silicon-based monolithic pressure-flow sensor has been developed. Its operation is based on the piezoresistive effect for pressure sensing and heat transfer for flow sensing. The sensor chip has a thermal isolation structure that is made of an oxidized porous silicon membrane. This structure thermally isolates the heating element located on the membrane from the rim of the chip. The sensor, in which the chip was mounted on a wall of an acrylate plastic pipe, was designed for biomedical applications. Measurements were made at pressures of 0-300 mmHg, water flow rates of 0-7 1/min, and fluid temperatures of 25-45°C. The temperature difference between the heating element and the fluid temperature sensing element was kept at 5°C. The sensor showed a pressure sensitivity of 1.32 µV/mmHg for 1-mA current supplied, a nonlinearity of 0.5 %F.S. for pressure sensing, an accuracy of ±10 %F.S. for flow sensing, and 90-percent response time of below 100 ms for flow sensing. The sensor was applied to the simultaneous measurements of pressure and flow rate in pulsedflow experimental systems. 相似文献
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Performance enhancement of PEMC liquid level sensor subjected to environmental temperature variation
A. A. Kashi M. Zamani M. Shamshirsaz M. Maroufi 《Analog Integrated Circuits and Signal Processing》2014,80(3):541-550
In this paper, the performance of a resonant Piezoelectric-excited Millimeter-sized Cantilever (PEMC) used as liquid level sensor has been studied. The sensitivity of this sensor affected by environmental temperature variation is investigated via theoretical and Finite Element Models (FEM). In order to validate this FEM, first, simulation results are compared with the theoretical and experimental ones for a sensor operating at constant room temperature. The simulation results are in a good agreement with experimental ones. Then, proposed theoretical model and FEM are used to study the dynamic behavior of the device when the environmental temperature is changed. The results indicate that although natural frequencies of sensor change due to temperature variation, the resultant shift remains almost the same regardless of specific immersion depths. Also, it can be concluded that temperature variation of about 50 °C affects the liquid level measurement accuracy up to 29 μm which is significant compared to a minimum detectable liquid level change of about 8 μm by this sensor reported previously in literature. 相似文献
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A differential temperature sensor for on-chip signal and DC power monitoring is presented for built-in testing and calibration applications. The amplifiers in the sensor are designed with class AB output stages to extend the dynamic range of the temperature/power measurements. Two high-gain amplification stages are used to achieve high sensitivity to temperature differences at points close to devices under test. Designed in 0.18 μm CMOS technology, the sensor has a simulated sensitivity that is tunable up to 210 mV/°C with a corresponding dynamic range of 13 °C. The sensor consumes 2.23 mW from a 1.8 V supply. A low-power version of the sensor was designed that consumes 1.125 mW from a 1.8 V supply, which has a peak sensitivity of 185.7 mV/°C over a 8 °C dynamic range. 相似文献
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《Electron Devices, IEEE Transactions on》1977,24(7):805-807
Uniform homogeneous alignment of nematic liquid crystals with low (<5°) tilt angles has been achieved by combining evaporated SiO layers at two angles of incidence. The first evaporation is performed at an incidence angle of 5°. The substrate is then rotated 90° about its normal and the second evaporation is performed at an incidence angle of 30°. The alignment tilt angle depends on the thickness of the second layer relative to that of the first. Low tilt angles are confirmed by observation of interference-type conoscopic figures. 相似文献