研制了一种基于单模光纤与多模光纤级联结构的马赫-曾德尔干涉型压力传感器, 它通过将一段单模光纤夹熔在两段多模光纤之间制成.利用纤芯的不匹配所激发的单模光纤中纤芯模和包层模之间的干涉, 使外界压力的变化直接作用于单模光纤内部光场, 获得较高灵敏度.当传感器总长度为39 mm时, 可获得较为理想的传输谱线.压力传感实验表明: 随着压力的增大, 传输光谱向长波方向漂移, 在2~16N的压力范围内, 传感器的压力灵敏度为554.830 pm/N, 线性度为0.984, 具有结构简单、易于制造、成本较低、灵敏度高等优点, 可用于不同领域的压力传感.

A novel Mach-Zehnder interferometer pressure sensor was proposed by cascading single mode fiber with multimode fiber. It was fabricated by just splicing a single mode fiber with two short section of multimode fibers. The core-cladding modes interference of the single mode fiber was obtained due to the core mismatch, which made the change of outside pressure more directly acted on the light field inside of the single mode fiber, so a high pressure sensitivity can be achieved. In order to obtain a well-defined interference pattern, the length of the sensor was defined as 39 mm after many experiments. The experimental results show that with the increasing of the pressure, the transmission spectrum of the sensor appears red shift phenomenon obviously, the pressure sensitivity of the sensor is 554.830 pm/N and the linearity is 0.984 in the range of 2~16N pressure changes. The sensor has advantages such as simple structure, easy manufacturing, low cost, high sensitivity and so on, it can be well applied to pressure sensing field.