采用0.004AgNO3-0.996NaNO3混合熔融盐,用离子交换技术在德国B270光学玻璃上制备了费米折射率分布渐变波导,理论分析了费米折射率分布渐变波导的包层吸收模谱特性,导波损耗测试实验验证了解析结果。在此基础上,提出了一种用于液体包层吸收损耗测试的双样品盒串连的波导回路,测试结果证实表征溶液包层吸收特征的折射率虚部与溶液浓度之间具有十分显著的线性关系,测试灵敏度与波导的模式和波导参量有关,尤其与波导层厚度有非常敏感的关联性。利用这个关系传感测试了13种不同浓度的耐晒果绿染料水溶液样品的浓度,结果显示测试值与实际配制浓度值的均方差小于0.07%。 The Fermi refractive index distribution gradient waveguide was prepared on German B270 optical glass by using 0.004AgNO3-0.996NaNO3 mixed molten salt. The clad mode absorption characteristics of Fermi refractive index distribution tapered waveguide were analyzed theoretically. Loss test experiments verify the analytical results. On the basis of this, a dual-sample waveguide circuit is proposed for the absorption loss test of liquid cladding. The test results confirm that there is a significant difference between the imaginary part of the refractive index and the solution concentration that characterizes the absorption characteristics of the solution cladding Linearity and test sensitivity are related to waveguide modes and waveguide parameters, especially the waveguide layer thickness. The concentrations of 13 different concentrations of fast-growing green-dye aqueous solutions were tested using this relationship-sensing method. The results showed that the mean square deviation of the measured and actual values ​​was less than 0.07%.