Abstract A reflective seawater salinity and temperature sensor based on surface plasmon resonance (SPR) effect with multimode single-mode (MS) fiber structure has been proposed and demonstrated. Firstly, the sensing mechanism of the optical fiber SPR sensor was analyzed. Next, the influence of the type of metal, the thickness of the metal film, and the length of sensing area upon the SPR spectrum were simulated and compared. Based on these measurements, a reflective and highly-sensitive refractive index sensor was fabricated and experimentally demonstrated. Finally, a dual-parameter SPR sensor for the simultaneous measurement of seawater salinity and temperature was proposed by coating polydimethylsiloxane (PDMS) on half of the sensor as a temperature sensitive material, whose sensitivities were demonstrated to be 0.31 nm/‰ and -2.02 nm/°C, respectively. The proposed sensor not only resolves the cross-sensitivity problem between salinity and temperature, but also provides a simple structure with low cost and high sensitivity.

中文翻译：

---

采用光纤表面等离子体共振 (SPR) 的盐度和温度传感器的理论和实验表征

摘要 提出并论证了一种基于表面等离子体共振（SPR）效应的反射式海水盐度和温度传感器，具有多模单模（MS）光纤结构。首先分析了光纤SPR传感器的传感机理。接下来，模拟和比较了金属类型、金属膜厚度和传感区长度对SPR光谱的影响。基于这些测量，制造并实验证明了反射性和高灵敏度的折射率传感器。最后，通过在传感器的一半上涂覆聚二甲基硅氧烷（PDMS）作为温度敏感材料，提出了一种用于同时测量海水盐度和温度的双参数 SPR 传感器，其灵敏度分别为 0.31 nm/‰ 和 -2.02 nm /°C, 分别。所提出的传感器不仅解决了盐度和温度之间的交叉敏感问题，而且提供了一种低成本和高灵敏度的简单结构。