光纤传感器在爆炸性危险场所的应用

为了探索光纤传感器在爆炸性危险场所的应用,弥补传统传感器在极端工作环境中的不足,针对国内外光纤传感器的发展现状,从非电气传感原理入手,结合光的点燃机理,阐述了其在防爆领域内应用的优势.通过对比电气传感器,从标准的角度说明了光纤传感器在爆炸性危险区域使用的可能性.介绍了国际标准IEC 60079-28中对光辐射设备的分类和考核依据,表述了光纤传感器在防爆领域应用前景巨大的观点.     

防爆LED灯具固有安全型光辐射试验方法探讨

目前,防爆LED灯具已越来越多地应用于爆炸性危险场所,但国内尚未出台针对光辐射引燃作用的标准规范。从揭示光辐射引燃作用的角度,论述了对防爆LED灯具光辐射的引燃机理、保护方式分类、光辐射安全限值以及合格判定;从光波角度,分析了防爆LED灯具连续波辐射与脉冲辐射两种发光方式光源评估方法的不同;通过色彩的叠加方式,分析了不同种类LED发光原理和光辐射特点;从满足固有安全型光辐射角度,探讨了优化LED驱动电路设计、应用固有安全特性LED和使用熔丝保护这3种方法,并对防爆LED灯具的光辐射设计要点进行了论述。总结了对光辐射试验结果造成影响的不同LED发光原理、灯具样品的选择、测试温度和测量距离的要求,探讨了不同温度下测试LED发光效率的新要求,阐述了验证不同LED发光原理的新方式,提出了实现本质安全光辐射设计的新方法,即熔丝保护法。     

工业用热辐射型光纤高温传感器的研究

在分析热辐射测温和光辐射与传输理论的基础上,采用“接触-非接触式”测温原理,研制成功了工业用热辐射型光纤高温传感器。它通过现场校准和工艺控制温度的方法,避开了确定辐射系数的难题。实验结果表明:该传感器可应用于指导批量生产,大大降低生产成本。     

基于光纤技术的叶尖定时传感器的设计

叶片振动测量对航空发动机、电站涡轮机及各种压气机的强度设计和研究及安全监测非常重要。光纤传感器的出现 ,克服了传统传感器的缺陷 ,为实时精确测量高速旋转叶片振动提供了可靠的保证。描述了基于光纤传感技术的叶尖定时传感器的设计及其性能。     

光纤传感器及其在物业管理中应用

随着科技的发展,物业管理更趋于网络化、智能化,而传感器则是所有信息的来源,因此传感器在物业管理中发挥者越来越大的作用.由于光纤技术的不断发展,传输距离不断加大,价格下降,加上在技术性能上又有独到的优点,光纤传感器将在物业管理中越来越多地得到应用.本文介绍了光纤传感器及其在住宅物业安全管理中的应用的设计思想,并提出组成光纤传感器网络,利用神经网络技术对信号进行实时处理,达到实时监控的目的.     

医用光纤传感器的应用

<正> 医用光纤传感器是一种用于病人连续监控生物功能的医疗仪器,在诊断和外科治疗中越来越起着重要作用。 美国华盛顿国际生物医学公司研制出一种应用光纤传感器和二极管激光器光源的血化验盒,还正在研制光纤多功能的化验包,它是应用光纤传感器测量电解质、药物量及代谢,使医生能按照病人的代谢情况进行供药,进行有效的药物治疗。美国TSI公司基于光纤传感器的输血监控诊断仪器,光纤传感器系统测量由循环红细胞所散射出的激光束多普勒位移(780nm),测量出血流速度。光纤传感器在心血管参量的实时测量中也     

黑体腔光纤高温传感器的原理与应用

光纤传感技术是近年来测量领域的热点之一。由于测量环境的恶劣和限制,使得在某些工业环境中,光纤传感技术的抗电磁干扰、耐腐蚀、防燃防爆等优势得以发挥,得到广泛的应用。本文研究了光纤温度传感的原理,并介绍了一种新型的光纤高温传感器。     

一种本安型有水信号传感器设计

为了在恶劣的舱底环境下安全、可靠地检出船舶进水情况,设计了一种本安型有水信号传感器。根据船舶应用的特点和传感器的工作环境,确定传感器类型和防爆形式,并设计传感器外形。根据传感器的物理特性和工作特性,计算传感器参数,并进行本质性能评定。试验验证表明:设计参数与实测值基本一致,可满足船舶蓄电池舱防爆等级的要求。该传感器已经广泛应用于各型船舶,并取得了良好的效果。     

基于光纤技术的叶定时传感器的设计

叶片振动测量对航空发动机、电站涡轮机及各种压气机的强度设计和研究及安全监测非常重要，光纤传感器的出现，克服了传统感器的缺陷，为实时精确测量高速旋转叶片振动提供了可靠的保证，描述了工于光纤传感技术的叶尖定时传感器的设计及其性能。     

光纤表面等离体激元共振传感器中光传播特性的理论分析

光纤表面等离体激元共振传感器是一种易于小型化的SPR传感器,常用于开发便携式传感检测设备,也可用于远距离实时在线检测.在本研究中,采用特制光纤作为导光介质来制作一种新的光纤SPR传感器.由于光纤中光传播相当复杂.仅凭过往经验来设计传感器将不能保证其检测精度.因此,针对本研究中光纤的特点,建立了光纤中光传播模型,并结合菲涅耳公式推导出该类光纤SPR传感器中光总反射系数与光波长的关系,最终绘制出理论SPR曲线并计算出共振波长.研究结果为该类光纤SPR传感器的设计及光谱分析提供了重要理论依据.     

光纤通信中的MOEMS光开关

光开关是一种重要的全光通信器件。MOEMS光开关阵列因其串扰小、插入损耗小、消光比高、对波长和偏振不敏感、且稳定性好、造价低等突出优点得到了国内外的广泛研究。本文介绍了MOEMS光开关的国内外研究进展。并对我国MOEMS光开关的研究提出建议。     

光纤通信系统中的光检测器件

论文介绍运用在光纤通信系统中的光检测器件的结构、工作原理及性能,并对PIN和APD两种光检测器件进行了比较。     

光学频率梳及光钟的实现

本文主要介绍了基于锁模飞秒脉冲激光器的光学频率梳的基本原理及应用，并阐述了飞秒脉冲激光器的锁模原理及实现锁模的方法。对光钟的基本原理和实现光钟的条件及相关技术做了详细的论述，并描述了光钟的各个组成部分和系统实现的原理。     

Optical Snow

Classical methods for measuring image motion by computer have concentrated on the cases of optical flow in which the motion field is continuous, or layered motion in which the motion field is piecewise continuous. Here we introduce a third natural category which we call optical snow. Optical snow arises in many natural situations such as camera motion in a highly cluttered 3-D scene, or a passive observer watching a snowfall. Optical snow yields dense motion parallax with depth discontinuities occurring near all image points. As such, constraints on smoothness or even smoothness in layers do not apply. In the Fourier domain, optical snow yields a one-parameter family of planes which we call a bowtie. We present a method for measuring the parameters of the direction and range of speeds of the motion for the special case of parallel optical snow. We demonstrate the effectiveness of the method for both synthetic and real image sequences.Supplementary material to this paper is available in electronic form at http://dx.doi.org/10.1023/A:1024440524579     

Optical clustering

This paper presents a definition of ‘optical clusters’ which is derived from the concept of optical resolution. The clustering problem (induced by this definition) is transformed such that the application of well known Computational Geometry methods yields efficient solutions. One result (which can be extended to different classes of objects and metrices) is the following: Given a setS ofN disjoint line segments inE ².

1. The optical clusters with respect to a given separation parameterr∈R can be computed in timeO(Nlog² N).
2. Given an interval [a, b] for the numberm(S, r) of optical clusters which we want to compute, then timeO(N log² N)[O(Nlog² N+CN)] suffices to compute the interval [R(b),R(a)]={r∈R/m(S,r)∈[a,b]} [allC optical clusterings withR(b)≦ r≦R(a)].

     

Parallel Optical Packet Address Detection Using Planar Optical Interconnections

We propose a novel planar optical interconnection scheme for 100 Gb/s optical packet address detection, which consists of wave guide grating couplers and a diffractive microlens integrated on a glass substrate 3-dimensionally. Length and duty cycle of the grating couplers have been determined on the bases of ray-optic propagation-mode analysis in a slab waveguide and of rigorous coupled-wave diffraction analysis for out-coupled radiation-modes. The 3-dimensionally integrated planar optics makes it possible to connect each address bit-signal of the TE₀-waveguide mode to the detector with a power uniformity of 6.4% and a total coupling efficiency of 72.3%.     

Thermal and Optical Characterization of Silicon-Based Tunable Optical Thin-Film Filters

In this paper, we report on the successful fabrication and comprehensive optical and electrothermal characterization of a silicon-based tunable optical filter. Of particular interest here are the static and transient electrothermal characteristics of the filter membrane. The filter is configured as a Fabry-Perot resonator with dielectric Bragg reflectors and is fabricated as a stress-compensated multilayer of dielectric thin-films. Tunability is achieved by changing the refractive index of the solid-state cavity material through thermal modulation, accomplished by Joule heating in metal thin-film resistors. The filter layers are configured as a membrane to provide good thermal isolation and its electrothermal behavior was characterized in steady-state and dynamically. A maximum stable temperature difference of 450 K and a heating efficiency of 13.4 K mW^-1 were measured with a thermal time constant for the filter hotplate of 3 ms. The filter's spectral width is 0.28 nm at a wavelength of 1550 nm and through thermal modulation it was possible to shift the filter peak over more than 29 nm.     

Coherent Optical Computing

Optical computing has a great many applications in data processing, owing in part to the high speed and parallelism inherent in optical devices.     

光缆制造业配纤管理系统的设计与实施

配纤是光缆生产中一个十分重要的环节。本文以光缆制造业管理信息系统为背景, 着重介绍了其中的配纤管理及其相关模块的设计与实现,同时概要介绍了本企业管 理信息系统。