为了提高光学折射法海水盐度检测精度,综合分析现有检测方法,认为其海水盐度检测精度低的主要原因是其检测光路为平行平板模型。由此,提出了棱镜模型多次折射法检测方案。利用棱镜模型而不是平行平板模型,提高了光线的偏折角;通过设置多个棱镜模块,进一步扩大偏折角,从而大大提高系统的分辨力。设计了光路并进行仿真分析,研制了样机并进行了海上实验。结果表明,盐度检测的分辨力达0.0012‰,重复性不大于±0.016‰。由海上与ALEC温盐传感器比测实验表明,与ALEC传感器一致性好,稳定性好,比测误差在±0.1‰以内。 In order to improve the detection accuracy of seawater salinity by optical refraction method, the existing detection methods are comprehensively analyzed. The main reason that the detection accuracy of seawater salinity is low is that the detection light path is a parallel plate model. Thus, the Prism model multi-refraction method is proposed. The use of a prism model instead of a parallel plate model increases the deflection angle of the light; by providing a plurality of prism modules, the deflection angle is further enlarged, thereby greatly improving the resolution of the system. The optical path was designed and simulated. The prototype was developed and the experiment at sea was conducted. The results show that the resolution of salinity detection is 0.0012 ‰ and the repeatability is no more than ± 0.016 ‰. By the sea and ALEC temperature and salt sensor ratio test shows that ALEC sensor consistency, good stability, the ratio error within ± 0.1 ‰.