一种高方向灵敏度光纤F-P超声传感系统设计研究

针对光纤F-P超声传感器工作点易偏离问题，设计了基于双波长稳定技术的低细度光纤F-P传感系统，建立了双波长光纤F-P传感系统的DE算法数学模型，优化设计了一高正交精度光纤F-P传感系统，建立基于该传感器的激光超声检测系统，实验研究了该传感器探测超声信号的有效性和方向灵敏度。结果表明，该传感器可以有效检测试样中激发出的超声表面波信号。激发源与传感器轴向夹角为0°时，表面波幅值最大。随着激发源与传感器轴向夹角增大，表面波幅值降低。激发源与传感器轴线垂直时，幅值下降达80%，说明该传感器有很强的方向性。

Design and Research of An Optical Fiber F-P Ultrasound Sensor With High Directivity Sensitivity

Optical fiber F-P ultrasound sensor deviates from working point easily in practical applications. The sys-tem of low fineness optical fiber F-P sensor is designed based on the technique of dual wavelength stabilization. A dual wavelength optical fiber F-P sensing system mathematical model of DE algorithm is set up. The sensing system with higher quadrature precision is optimized and designed. Laser ultrasound detection system is established based on the sensor. Experimental research on the effectiveness of the sensor to detect ultrasonic signal sensitivity and di-rection is processed. The results show this sensor can detect ultrasound surface wave signals availably. The ampli-tude of surface wave is the biggest when the angle between laser source and sensor’s axial direction is zero degree. And the amplitude of surface wave decreases along with increasing the angle between laser source and sensor’s axial direction. The amplitude descends 80% when the angle between laser source and sensor’s axial direction is ninety degree. These demonstrate that the sensor has sensitive directivity.