| Energy is the basis of the safety of national economy and even of the country itself. The safety of petroleum supplies is important in the safety of national energy. To solve our country energy crisis, it is urgent to prospect new oil fields or other energy. As the easily discoverable energy has been exploited, the prospecting will become more and more difficult, and we need to improve the prospecting technology urgently. Seismic geophone, which work first in the seismic prospecting, decide the quality of the collected seismic data. The research work of the dissertation is the main research item of the project "The theoretical and experimental research on photo-electronic integrated acceleration seismic geophone technology" , supported by National Natural Science Foundation of China. A novel MOEMS acceleration seismic geophone has been developed. Combining MEMS technology with Integrated optical technology, it is of the advantages such as potential high sensitivity, wide bandwidth, high degree of accuracy and environmental ruggedness, and suitable for mass production. It is also possible to overcome optical alignment ,long-term stable and handing of fiber in package process when optical fiber sensor is minimized and go into mass production. The research work of the dissertation mainly includes four aspects as follows: 1. Kinds of optical modulation sensors, especially lightwave phase modulation sensors are studied. Sensor principle of waveguide sensor based on light phase modulation is researched. The phase change, generated by stress-strain effect and temperature-strain effect, is analyzed. Starting with the crystal optics theory, the phase change, generated by photoelastic effect, is derived. The methods for lightwave phase demodulation are discussed. 2. Analysis of the static and dynamic behavior of Si-based MOEMS acceleration seismic geophone are given and the optimization structure design of the harmonic oscillator is obtained. Starting with small-deflection theory and bending stress theory of beam, the beams' length change of the harmonic oscillator is derived, and beams' stress-strain is also obtained using general Hooke's law. And the phase sensitivity is discussed. The mathematical model of the MOEMS acceleration seismic geophone is established, and amplitude, phase frequency response characteristics and damping effect are studied. On the basis of above analysis, optimization structure design of the harmonic oscillator is obtained. The simulation of behavior of sensor is performed by the FEM software ANSYS. Measuring range and cross-axis sensitivity are discussed. The work condition of the small-deflection theory is verified. 3. Mach-Zehnder waveguide interferometer of Si-based MOEMS acceleration seismic geophone is researched and its optimization structure design is accomplished. Starting with waveguide ray theory, the condition for single-mode waveguide is derived, and design of single-mode strip waveguide is accomplished with effective index method. The working principle and loss characteristics of Y-branching waveguide are studied, and waveguide turning mirror with a 90°directional change is employed and designed. The Helmholtz equation, the intrinsic equation of waveguide, is derived. BPM (beam propagation method), one of its' numerical solution, is studied and employed to simulate the lightwave propagation in Y-branching waveguide. The polarizer , which adapts structure of metal cladding/dielectric buffer layer, is studied, and TE mode polarizer is designed. 4.Lots of theoretical and experimental research on process craft of waveguide interferometer and harmonic oscillator have been done. A feasible process flow is made and valuable technological parameter are obtained. And Mach-Zehnder waveguide interference chip is fabricated successfully and the optical measurement is executed. A harmonic oscillator is also processed.
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