A compact, stable, low cost and high sensitivity fiber salinity sensor based on single mode fiber-single mode fiber-no-core fiber-single mode fiber-single mode fiber (SSNSS) structure is proposed and demonstrated. It is proved by experiments and simulations that the sensor has high sensitivity to external refractive index (RI) changes, so as to achieve the purpose of gauging the seawater salinity. When the RI of surrounding media in sensing area changes, the absolute value of sensitivity for the refractive index measurement can be above 16,000 nm/refractive index unit (RIU) that is higher than other fiber salinity sensors as we known. In the experimental study, a fiber salinity sensor with the sensitivity of up to -3.42 nm/‰ was achieved when the salinity varied between 0‰ and 40.001‰, and the sensor showed a good linear response.

提出并证明了一种基于单模光纤单模光纤无芯光纤单模光纤单模光纤（SSNSS）结构的紧凑，稳定，低成本，高灵敏度的光纤盐度传感器。通过实验和仿真证明，该传感器对外部折射率变化具有很高的灵敏度，从而达到了测量海水盐度的目的。当传感区域中周围介质的RI发生变化时，用于折射率测量的灵敏度的绝对值可能会高于16,000 nm /折射率单位（RIU），高于我们所知的其他纤维盐度传感器。在实验研究中，当盐度在0‰至40.001‰之间变化时，可获得灵敏度高达-3.42 nm /‰的纤维盐度传感器，并且该传感器具有良好的线性响应。