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本征不对称光纤法布里-珀罗干涉仪的理论模型 总被引:9,自引:1,他引:8
应用光学和数学理论导出本征不对称光纤法布里-珀罗干涉仪中反射光与透射光的数学模型及低反射率法布里-珀罗干涉腔长度的变化与干涉光光强的数学模型,半指出当r11=t1t1r2=r,且t1t1=1-r1^2≈2。则法布里-珀罗腔反射光间的干涉近似为两束等幅光的干涉;文章还给出了光电转换器输出与法布里-珠罗干涉腔长度变化的数学模型。这些模型为不对称光纤法布里-珀罗干涉仪的使用提供理论依据。 相似文献
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提出了一种新的白光非本征法布里-珀罗干涉(EFPI)光纤传感系统的干涉谱处理方法,在白光法布里-珀罗干涉光纤传感系统中,一个中心波长为850nm的发光二极管(LED)作为宽谱光源,HR2000高分辨力微型光谱仪用来测量返回的干涉光谱。通过跟踪干涉光谱中的特定谱峰点,法布里-珀罗干涉传感器的腔长值可以被解调出来。应用反向传播神经网络,解决了单峰测量方式的级次模糊问题。反向传播神经网络能够分辨出干涉谱中不同谱峰的干涉级次,因而可以进行多个谱峰的连续跟踪。从而实现了高精密度、大动态范围的测量。进行了基于这种干涉谱处理方法的白光法布里-珀罗干涉传感系统的应变测量实验。利用该传感系统实现了精密度达0.1με,500με范围的应变测量。 相似文献
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介绍光纤应变传感器中光纤端面反射镜的制作方法,镀膜光纤的连接技术和构成不对称光纤法布里-珀罗干涉腔的方法。应用低反射率不对称光纤法布里- 珀罗干涉腔与光纤连接构成的光纤应变传感器,以提高分辨率;重点导出此干涉腔反射光与应变的数学模型,论述其工作原理和测量方法,通过实验证明文中所述应变传感原理和测量方法是正确的,其分辨率优于0-0068με。 相似文献
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基于掺铒光纤的微型光纤法布里-珀罗干涉传感器 总被引:1,自引:1,他引:0
提出了一种化学腐蚀掺铒光纤制作微型光纤法布里-珀罗干涉传感器的方法。通过对掺铒光纤进行化学腐蚀,形成凹槽,再与单模光纤直接熔接制作而成。实验制作的微型法布里-珀罗干涉传感器干涉条纹光滑,对比度达到15dB。对该微型光纤法布里珀罗干涉腔进行了应变和温度传感实验。实验结果表明,在0-600με£内,波谷移动随应变改变的灵敏度达到1.7pm/με,线性度为0.9998,从73~23℃,波谷移动随温度改变的灵敏度3.9pm/℃,线性度为0.9982。该方法制作的微型光纤法布里-珀罗传感器具有操作简单,一次成型,制作成本低的优点。 相似文献
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提出并实验验证了一种基于匹配光纤光栅法布里-珀罗干涉仪的应变传感器解调方法,该方法综合了光纤法布里-珀罗干涉技术和匹配光纤光栅滤波法的优点.通过半导体制冷片和压电陶瓷组成的闭环负反馈控制系统,精确调节匹配光栅法布里-珀罗干涉仪的温度和应变,有效解决了光栅法布里-珀罗干涉仪的失配问题,从而保证系统静态工作点处于最佳匹配位置,同时能够避免探头因环境温度波动导致的测量误差.实验结果表明,该系统能够响应50~800 Hz的输入信号,应变最小分辨力至少为0.4 nε/Hz1/2,解调灵敏度高,且不受环境温度波动的影响,因而在动态应变或振动测量中具有较高的实用性. 相似文献
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基于匹配光纤光栅法布里-珀罗干涉仪的应变解调方法 总被引:2,自引:1,他引:1
提出并实验验证了一种基于匹配光纤光栅法布里-珀罗干涉仪的应变传感器解调方法,该方法综合了光纤法布里-珀罗干涉技术和匹配光纤光栅滤波法的优点.通过半导体制冷片和压电陶瓷组成的闭环负反馈控制系统,精确调节匹配光栅法布里-珀罗干涉仪的温度和应变,有效解决了光栅法布里-珀罗干涉仪的失配问题,从而保证系统静态工作点处于最佳匹配位置,同时能够避免探头因环境温度波动导致的测量误差.实验结果表明,该系统能够响应50~800Hz的输入信号,应变最小分辨力至少为0.4nε/Hz1/2,解调灵敏度高,且不受环境温度波动的影响,因而在动态应变或振动测量中具有较高的实用性. 相似文献
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提出利用n≈k的金属膜层材料设计窄带反膜的一种新方法-用超薄金属膜与不对称法布里-珀罗干涉滤光组合设计法,给出了可光光区窄带高反膜的膜系结构,定量地分析了膜系的反射率,反射峰值,反射半波带宽光谱反射特性,实验证实了理论设计和分析,同时,也提供了设计非可见光波段的窄带高反滤光片的方法。 相似文献
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对干涉式光纤传感器来说,光源的谱宽直接影响着传感器的工作特性。从法布里—珀罗干涉式光纤传感器出发,推导其灵敏度的理论表达式,并用MathCAD软件进行了数学分析。讨论了光源谱宽对传感器灵敏度的影响。介绍了具有温度反馈功能的法布里—珀罗光纤干涉实验系统,给出了用该实验系统拍摄的谐振曲线照片。从该系统进行的两个重要的实验(不同干涉腔长的灵敏度对比实验和不同干涉长度的光源实验)表明,法布里—珀罗干涉式光纤传感器的灵敏度与光源谱宽的理论表达式是正确的,理沦公式与实验结论能很好地吻合。最后指出了该方法可以用于分析其他类型的干涉式光纤传感器的灵敏度问题,为光源的选择提供了参考。 相似文献
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提出利用n≈k的金属膜层材料设计窄带高反膜的一种新方法用超薄金属膜与不对称法布里-珀罗干涉滤光片组合设计法。给出了可见光区的窄带高反膜的膜系结构;定量地分析了膜系的反射率、反射峰值、反射半波带宽等光谱反射特性。实验证实了理论设计和分析。同时,也提供了设计非可见光波段的窄带高反滤光片的方法 相似文献
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Separation of liquid mixtures in a thermal gradient, known as the Ludwig-Soret effect or thermal diffusion, is governed by a nonlinear, partial differential equation. It is shown here that the nonlinear differential equation for a binary mixture can be reduced to a Hamiltonian system of equations and that a solution can be obtained for the linear problem. The calculation gives a closed form expression for the space and time dependence of the concentration profile of the mixture, valid at short times. 相似文献
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为了构造高维非线性发展方程的无穷序列类孤子新解, 研究了二阶常系数齐次线性常微分方程, 获得了新结论. 步骤一, 给出一种函数变换把二阶常系数齐次线性常微分方程的求解问题转化为一元二次方 程和Riccati方程的求解问题. 在此基础上, 利用Riccati方程解的非线性叠加公式, 获得了二阶常系数齐次线性常微分方程的无穷序列新解. 步骤二, 利用以上得到的结论与符号计算系统Mathematica, 构造了(2+1)维广义Calogero-Bogoyavlenskii-Schiff (GCBS)方程的无穷序列类孤子新解.
关键词:
常微分方程
非线性叠加公式
高维非线性发展方程
无穷序列类孤子新解 相似文献
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Homogeneous balance method for solving nonlinear partial differential equation(s) is extended to solving initial-value problem and getting new solution(s) from a known solution of the equation(s) under consideration. The approximate equations for long water waves are chosen to illustrate the method, infinitely many simple-solitary-wave solutions and infinitely many rational function solutions, especially the closed form of the solution for initial-value problem, are obtained by using the extended homogeneous balance method given here. 相似文献
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A new expansion method of first order nonlinear ordinary differential equation with at most a sixth-degree nonlinear term and its application to mBBM model
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Based on a first order nonlinear ordinary differential equation with at most a sixth-degree nonlinear term which is extended from a type of elliptic equation, and by converting it into a new expansion form, this paper proposes a new algebraic method to construct exact solutions for nonlinear evolution equations. Being concise and straightforward, the method is applied to modified Benjamin-Bona-Mahony (mBBM) model, and some new exact solutions to the system are obtained. The algorithm is of important significance in exploring exact solutions for other nonlinear evolution equations. 相似文献
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An exact invariant is derived for n‐degree‐of‐freedom non‐relativistic Hamiltonian systems with general time‐dependent potentials. To work out the invariant, an infinitesimalcanonical transformation is performed in the framework of the extended phase‐space. We apply this approach to derive the invariant for a specific class of Hamiltonian systems. For the considered class of Hamiltonian systems, the invariant is obtained equivalently performing in the extended phase‐space a finitecanonical transformation of the initially time‐dependent Hamiltonian to a time‐independent one. It is furthermore shown that the invariant can be expressed as an integral of an energy balance equation. The invariant itself contains a time‐dependent auxiliary function ξ (t) that represents a solution of a linear third‐order differential equation, referred to as the auxiliary equation. The coefficients of the auxiliary equation depend in general on the explicitly known configuration space trajectory defined by the system's time evolution. This complexity of the auxiliary equation reflects the generally involved phase‐space symmetry associated with the conserved quantity of a time‐dependent non‐linear Hamiltonian system. Our results are applied to three examples of time‐dependent damped and undamped oscillators. The known invariants for time‐dependent and time‐independent harmonic oscillators are shown to follow directly from our generalized formulation. 相似文献
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Using functional derivative technique in quantum field theory, the algebraic dynamics approach for solution of ordinary differential
evolution equations was generalized to treat partial differential evolution equations. The partial differential evolution
equations were lifted to the corresponding functional partial differential equations in functional space by introducing the
time translation operator. The functional partial differential evolution equations were solved by algebraic dynamics. The
algebraic dynamics solutions are analytical in Taylor series in terms of both initial functions and time. Based on the exact
analytical solutions, a new numerical algorithm—algebraic dynamics algorithm was proposed for partial differential evolution
equations. The difficulty of and the way out for the algorithm were discussed. The application of the approach to and computer
numerical experiments on the nonlinear Burgers equation and meteorological advection equation indicate that the algebraic
dynamics approach and algebraic dynamics algorithm are effective to the solution of nonlinear partial differential evolution
equations both analytically and numerically.
Supported by the National Natural Science Foundation of China (Grant Nos. 10375039, 10775100 and 90503008), the Doctoral Program
Foundation of the Ministry of Education of China, and the Center of Nuclear Physics of HIRFL of China 相似文献
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A. R. Gharaati N. Riazi and F. Mohebbi 《International Journal of Theoretical Physics》2006,45(1):53-63
We apply a linear perturbation analysis to investigate the relationship between soliton oscillations and the integrability of nonlinear PDEs in bi-dimensional spacetime. For this purpose, we consider a localized solution of the nonlinear differential equation, and study small amplitude fluctuations around it. The linearized equation is a Schrödinger-like, eigenvalue problem. By considering several nonlinear PDEs, which are known to have soliton and solitary wave solutions, we find that in systems which are integrable, this eigenvalue equation has one and only one bound state with zero frequency. Non-integrable equations—in contrast—show extra bound states. The time evolution of the oscillations are also calculated, using a numerical program to integrate the time-dependent equation. The behavior of the modes are studied, using the Fourier transform of the evolving solutions. 相似文献