光电探测器组件光纤耦合移位特性分析

摘要

The responsibility decrease of photo-detector will cause abnormal output of fiber optical gyroscope, whose main reason is fiber coupling dislocation. To solve this problem, the relations of fiber coupling efficiency coefficient variation with fiber coupling distance and fiber deflection angle are derived by calculating the digital integration of the incident Gaussian beam on the cross section of the photo- detector chip. The calculations are conformed to the real device specification. Based on the calculation results, the causes of coupling dislocation are analyzed in terms of fiber dislocation, photo-detector chip dislocation and shell deformation. Meanwhile, effective measures are proposed to prevent the photo-detector coupling dislocation. Moreover, experiment results verify that the coupling weld defects will cause the responsibility decrease of photo-detector, while the responsibility keeps stable for the devices packaged with coupling alignment measures.%光电探测器组件响应度下降会造成光纤陀螺输出异常，响应度下降的主要原因为光纤耦合移位，分析光纤耦合移位的原因并采取有效措施可提高探测器组件的使用可靠性。通过对探测器尾纤出射高斯光斑在探测器管芯端面数学积分，计算出光纤耦合效率系数与光纤耦合间距及光纤偏转角度的关系，计算结果与实际封装探测器组件指标一致。根据计算结果，从光纤移位、探测器管芯移位和管壳形变三个方面分析了耦合移位的影响因素，提出避免探测器使用中发生耦合移位的措施，并通过试验验证了耦合焊接缺陷会造成探测器试验后响应度下降，采取耦合对准控制措施后封装的探测器试验后响应度保持稳定。