An investigation of the properties ofa LiNbO3 photoelastic waveguide via the acceleration-induced effect is presented. A novel three-component hybrid-integrated optical accelerometer based on a Mach-Zehnder interferometer with a LiNbO3 photoelastic waveguide has been designed, which is capable of detecting seismic acceleration in high-accuracy seismic exploration. The Mach-Zehnder interferometer was successfully fabricated and a lighting test used to check its quality. The frequency response characteristic of the accelerometer was measured2 The accelerometer with a resonant frequency of 3549 Hz was demonstrated to show good linear frequency responding characteristics in the range of 100-3000 Hz. The accelerometer also shows good stability and consistency. Experimental results indicate that the outputs of the on- and cross-axis are 147 and 21.3 mV, respectively.
A novel three-component hybrid-integrated optical accelerometer based on LiNbO3 photoelastic waveguide is presented. The photoelasitcity of LiNbO3 due to three-dimensional stress states is obtained analytically. We analyze the level of sensitivity to cross-axis accelerations which is a very important parameter for three-component accelerometer. Theoretically, the designed three-component hybrid-integrated optical accelerometer has a transverse sensitivity ratio （TSR） of zero. The sensor has a high natural frequency of 3.5 kHz and a linear broad working freauency.
In order to realize a high accuracy seismic exploration in the high electro-magnetic field and to improve oil producibility and recovery efficiency,a three-component photoelastic waveguide accelerometer is designed. Based on the photoelastic effect,the Mach-Zehnder integrated optical interferometer is designed to measure the three-orthogonal components of acceleration and the combined three-component simple harmonic vibrator is designed to reduce the cross-talk among the acceleration components. According to the variation of LiNbO3 waveguide phase under the action of the applied acceleration,the cross-axise sensitivity and transverse sensitivity ratio(TSR) were analysed. The results reveal that the accelerometer has wide band and good linearity. It can satisfy the sensor requirements of high accuracy seismic exploration. The main design parameters of the geophone system are:phase sensitivity:1.86×10-4 Rad·m-1·s-2,natural frequency:3 500 Hz,and the transverse sensitivity ratio:0.11%.
为了实现强电磁场环境下的三维地震高精度勘探,提出了一种新型的三分量光波导加速度传感器。对三分量光波导加速度传感器的双M-Z光波导干涉仪进行了研究和优化设计。用有效折射率法(E IM)分析了T i∶L iN bO3波导的单模传输并设计了单模波导。双M-Z光波导干涉仪的Y分支设计采用反正弦S型弯曲,并用有限差分光束传播法(FD-BPM)对干涉仪中光传输进行了理论分析和模拟计算,实验与理论分析吻合。对成功制作的双M-Z干涉芯片进行了测试。实验结果表明,干涉芯片性能良好。
