经过了近些年的发展，干涉型光纤折射率传感器正渐渐走进我们的眼帘，已经广

After recent years of development, interferometric optical fiber refractive index sensors are gradually entering our eyes, and have been widely used for real-time detection of multiple temperatures to be measured, such as the temperature, concentration, refractive index, and slight deformation and vibration of substances. Compared with other sensors composed of other materials, optical fibers have more prominent advantages, such as low loss, smaller volume, lighter weight, relatively low manufacturing cost, and less interference from electromagnetic interference. In the detection of special environments, everyone focused on the fiber optic sensor. Among them, MZ interferometric sensors have been widely recognized in the field of optical fiber sensing due to their unique structural advantages. <br>In recent years, more and more scholars have studied and reported on fiber optic sensors based on side polishing. Some sensors are filled with metal inside the fiber. Although the sensitivity of this type of sensor is high, the analyte to be detected still needs to be internally filled with a special method. This complex processing method greatly reduces the convenience of the sensor, and ordinary sensors are gradually unable to meet the growing needs, which limits the wide application of sensors. In order to increase the convenience of fiber optic sensors, scholars have begun to optimize the sensor from the perspective of changing the fiber structure parameters. One of the methods is to make the D-groove by polishing the fiber on the side. This is convenient because such sensors can be directly inserted into the analysis The analyte does not need to be filled into the cladding of the optical fiber by other means, which is not only convenient but also has good sensitivity. <br>In this paper, in the research based on MZ interference caused by fiber misalignment fusion, the method of side polishing is used to increase the sensitivity of the sensor, and a sensor with high sensitivity based on MZ misalignment D-type PCF refractive index is designed.

经过了近些年的发展，干涉型光纤折射率传感器正渐渐走进我们的眼帘，已经广泛应用于对物质的温度、浓度、折射率以及微量的形变、振动等多个待测量的实时检测。相对于其他物质构成的各种传感器，光纤具备比较突出的长处，比如损耗教低、体积更小、重量更轻、制作成本相对较低、电磁对其干扰也较小等优点，所以在地震等特殊环境的探测中，大家把目光聚焦在了光纤传感器上。其中M-Z干涉型传感器凭借独特的结构优势，在光纤传感领域得到了广泛的认可。<br>近年来，越来越多的学者对基于侧面抛磨的光纤传感器进行了研究和报道。一些传感器在光纤内部填充了金属。虽然这类传感器的灵敏度很高，但要检测到的分析物仍然需要用特殊的方法进行内部填充。这种复杂的处理方式大大降低了传感器的方便性，普通的传感器逐渐不能满足日益增长的需要，限制了传感器的广泛应用。为了增加光纤传感器的便利性，学者们开始从改变光纤结构参数的角度对传感器进行优化，其中一种方法就是通过侧面抛磨光纤制作D型槽，这样的方便在于这类传感器可以直接插入被分析物进行检测，而被分析物不需要通过其他方式填充到光纤的包层中，不仅方便而且具有不错的灵敏度。<br>本论文在基于光纤错位熔接引起M-Z干涉的研究中，利用侧面抛磨的方法来增大传感器的灵敏度，设计出一种基于M-Z错位D型PCF折射率且具有高灵敏度的传感器。

After the development in recent years, the interferometric fiber-optic refractive index sensor is gradually coming into our eyes. It has been widely used in the real-time detection of temperature, concentration, refractive index, micro deformation, vibration, etc. Compared with various sensors made of other materials, optical fiber has outstanding advantages, such as low loss, smaller volume, lighter weight, relatively low manufacturing cost, and less electromagnetic interference. Therefore, in the detection of special environment such as earthquake, we focus on optical fiber sensor. M-Z interference sensor is widely recognized in the field of optical fiber sensing because of its unique structural advantages.<br>In recent years, more and more scholars have studied and reported the fiber optic sensor based on side polishing. Some sensors are filled with metal inside the fiber. Although the sensitivity of this kind of sensor is very high, the analyte to be detected still needs to be filled with special methods. This complex processing method greatly reduces the convenience of the sensor, and the common sensor gradually can not meet the growing needs, which limits the wide application of the sensor. In order to increase the convenience of optical fiber sensor, scholars began to optimize the sensor from the perspective of changing the structural parameters of optical fiber. One of the methods is to make d-groove by side polishing optical fiber. Such convenience lies in that this kind of sensor can be directly inserted into the analyte for detection, and the analyte does not need to be filled into the cladding of optical fiber by other ways, which is not only convenient And it has good sensitivity.<br>In this paper, based on the research of M-Z interference caused by optical fiber dislocation fusion, the method of side polishing is used to increase the sensitivity of the sensor, and a kind of sensor with high sensitivity based on d-pcf refractive index of M-Z dislocation is designed.<br>