Fibre optic sensor for physiological parameters

A fibre optic sensor structure is proposed for recovering the most relevant physiological parameters aiming at identifying the different sleep phases. The device comprises a multimode loss fibre optic sensor built into a watch casing. The sensor structure generates micro-deformations and allows a sensor to be made which is sensitive enough to detect the composite signal from the patient's wrist     

Fibre optic interferometer using integrated optics

A fibre optic Mach-Zehnder interferometer has been constructed using channel waveguides in LiNbO3 as splitters and combiners and integrating the phase-tracking component on the LiNbO3 device. The results are discussed and improvements are suggested.     

Fibre optic modulators using active multimode waveguide overlays

The evanescent field coupling between a singlemode optical fibre, side polished close to the core and a high index, multimode, planar waveguide overlay has been investigated as a means of realising inline modulators without interruption of the fibre. Oils of known refractive index and thin layers of polished lithium niobate have been used in the role of the overlay and an electro-optic inline intensity modulator based on the latter has been realised and tested. The results demonstrate the technical feasibility of fabricating rugged, low loss solid state devices offering performances which are realistic in terms of applications.<>     

基于双金属膜片结构的海底地震勘探光纤加速度传感器研究

针对全光海底地震检波器技术的特殊应用需求,设计了一种基于双金属矩形膜片的缠绕式光纤加速度传感器。利用弹性力学理论对光纤加速度传感器的加速度灵敏度和一阶共振频率的特性进行了分析,制作了光纤加速度传感器样品并对其性能进行了测试。结果表明,本文加速度传感器的灵敏度为45dB re∶0dB=1rad/g,一阶共振频率在820Hz左右,与理论分析值很好吻合。在10～400Hz工作带宽中,交叉去敏度约为30dB。测试系统中,使用的相位生成载波(PGC)解调算法的最小相位检测精度为10-5 rad/Hz1/2,因此理论能探测的最小加速度信号为56ng/Hz1/2。由于采用全金属结构,本文类型光纤加速度传感器能够更好地满足海底永久布放检波器的特殊要求。     

Fibre optic analogue transmission experiment for high-definition television signals using semiconductor laser diodes

The transmission characteristics of 30 MHz analogue colour t.v. signals are investigated using a semiconductor laser diode at the 1.3 ?m wavelength. Transmission over 17 km with 40.3 dB unweighted s.n.r. is confirmed, and transmission over 30 km is feasible using a 1.3 ?m laser diode and low-loss single-mode fibres.     

Fibre optic device for simultaneous laser power transmission and temperature measuring of irradiated object

A fibre optic device is described on the base of polycrystalline KRS-5 fibre for CO2-laser power transmission to the irradiated object and for simultaneous measurement of its temperature by its IR radiation.     

High-sensitivity fibre-optic accelerometer

A sensitive accelerometer is described, in which single-mode optical fibre is used to detect acceleration induced dimensional changes in a compliant cylinder. The device sensitivity and overall frequency response can be tailored through a suitable choice of the compliant material employed. Sensitivities better than 1000 rad/g (10 m/s2) are exhibited using rubber as the compliant material.     

机械式科氏加速度演示仪

针对科氏加速度教学展示难、理解难这一现象,介绍一种直观展示科氏力并证明科氏力影响因素的演示仪。运用行星机构实现多种模式的切换,空间传动机构实现矢量夹角的调节。引入无线摄像头对现象进行直观展示。科氏力作用于指针使其发生偏转,指针上的画笔记录指针轨迹进行定量分析。实践结果表明：该装置现象明显,通过对实验结果进行分析,得出指针偏角与转速和矢量夹角的关系,准确的揭示了科氏力与影响因素之间的关系。     

A novel optical accelerometer

A novel accelerometer based on a PIN photo-detector and a micro-machined cantilever-beam-supported optical shutter with seismic mass has been designed, fabricated, and tested. Anisotropic wet etching of 〈110〉 orientation silicon in KOH is used to fabricate an optical shutter consisting of evenly spaced vertically etched slots. The shutter, which also constitutes the seismic mass of the accelerometer, is suspended by two cantilever beams. The special structure of the device and the high aspect ratio of the cantilever beams (7.5) permit freedom of the movement for the proof mass (the shutter) on the ±X axis only. The actual size of the device is 3×4 mm and its amplified output varies linearly from -3.6 V to +3.6 V for accelerations from -84 g to +84 g. The measured resonant frequency of the device is 3.2 KHz. A dual diode structure is chosen for the photo-detector to compensate for temperature drift and the amplified output voltage changes by less than 40 mV for a temperature variation from 25°C to 50°C     

A batch-fabricated silicon accelerometer

An extremely small batch-fabricatable accelerometer has been developed using silicon IC technology. The device, 3 mm long and weighing 0.02 g, is a simple cantilevered beam and mass structure sealed into a silicon and glass package. The fabrication of the accelerometer is described, and the theory behind its operation developed. Experimental results on sensitivity, frequency response, and linearity are presented and found to agree with theory. The accelerometer is capable of measuring accelerations from 0.001 to 50 g over a 100-Hz bandwidth, while readily implemented geometry changes allow these performance characteristics to be varied over a wide range to meet the needs of differing applications.     

Integrated silicon microbeam PI-FET accelerometer

Integrated accelerometers showing excellent linearity have been designed and fabricated using silicon planar technology, zinc-oxide sputtering, and anisotropic etching. Small cantilevered beam structures overcoated with piezoelectric ZnO films act as force transducers, and the electrical signal is directly coupled to the gate of a depletion-mode, p-channel MOS transistor. The accelerometers have a nearly flat response from very low frequencies until beam resonances become significant (above 40 kHz). The near-dc response results from completely isolating the piezoelectric film from electrical leakage paths. Measured performance has matched very well with theory. Theoretical analysis has been used to derive useful design tradeoffs.     

引信用高g加速度计研究

高g加速度计具有高过载、高响应速度、高环境压力以及体积小和价格低等特点。我们开发的新型电容式加速度计,具有10万g的量程,能够实现高g环境下的加速度测量,满足了用户的要求。基于有限元模拟和经验数值结合的办法,在大量程和灵敏度之间综合考虑,确定了高g的设计思路,并采用硅溶片工艺制备了满足设计要求的MEMS加速度计。     

锥形光纤与楔形光纤的耦合

用实验方法测量了楔形光纤与锥形光纤的耦合效率,作出耦合效率随楔形光纤的半楔角及锥形光纤半圆锥角的变化曲线。从实验结果可以看出,楔形与锥形光纤的耦合效率随半楔角增加而增大。当半楔角由15.0°增大到30.3°,半楔角由44.9°增大到55.2°时,耦合效率曲线呈较快的上升趋势;当半楔角由30.3°增大到44.9°时,耦合效率曲线上升趋势变缓。当锥形光纤半圆锥角增加时,耦合效率也随着增大;并且随着楔形与锥形光纤的间距的减小而增大,在间距由0.10mm减小到0.03mm时,耦合效率曲线呈较快的上升趋势;在间距由0.03mm减小到0.01mm时,耦合效率曲线呈下降趋势。     

光纤Bragg光栅及其在光纤通信中的应用

本文对光纤光栅的光学特性和制造技术进行了介绍，并对其在制作高性能光纤器件方面的几种典型应用进行了评述     

pDCH聚合物纤维在传感器中的应用

介绍了pDCH聚合物纤维的结构、制作方法、力学性能,综述了该纤维与环氧树脂复合成复合材料的应力转移效果等问题的研究现状,提出并论述了它同时作为增强纤维材料和传感材料使用的可行性。     

吹光纤布线系统

本文介绍了新型光纤布线系统－吹光纤布线系统。该系统通过吹入空气来安装光纤，它由微管和微管组，吹光纤，附件和安装设备组成。具有设计简单，安装方便等特点，便于网络升级换代，更有效地满足用户需求。     

光纤浊度仪

光纤浊度仪是测量水中杂质含量及其变化的一种仪器,该仪器具有测速快和准确性高的特点。本文介绍了仪器的原理结构及主要参数。     

光纤传感器

本文扼要介绍了光纤传感器的基本原理。着重描述了具有实用价值的几种光纤传感器的结构及其性能。最后对光纤传感器的发展提出了一些粗浅的看法。