基于荧光强度比值法, 设计了一种使用两种荧光染料的光纤温度传感器.实验中, 罗丹明B和罗丹明110分别为对温度敏感和对温度不敏感的荧光传感物质, 利用聚合物光纤来传导激发光及接收荧光.由于两种染料的荧光谱峰相距60 nm, 因此容易将二者对应的荧光谱分开.通过确定能代表两种染料的最优荧光光谱范围, 获得具有良好线性度的温度-荧光强度标定曲线.实验研究了不同浓度的荧光染料对标定曲线的影响, 当染料浓度为0.3 g/L时, 可获得0.28℃的最小均方误差及0.0128/℃的灵敏度.此外, 该传感器还具备一定的抗光源扰动和抗荧光染料漂白的能力.

An optical fiber temperature sensor using two fluorescent dyes based on Fluorescence Intensity Ratiometric (FIR) method was proposed. In experiment, Rhodamine B and Rhodamine 110, which were temperature-sensitive and temperature-insensitive respectively, acted as the sensing materials. Polymer optical fibers were utilized to transmit excitation light and collect emitted fluorescence. The two dyes- fluorescence spectra could be separated conveniently since their respective emission peaks were 60 nm apart. The optimal spectral intervals of RH110 and RHB for FIR were identified. By calculating the fluorescence intensity ratio of the two dyes, the calibration curves of intensities ratios vs temperature were obtained with good linearity. The effects of different concentrations of fluorophore on the calibration curves were also studied. When the concentrations of dyes were 0.3 g/L, a minimum rms temperature error of 0.28℃ and a sensitivity of 0.0128/℃ were achieved. Moreover, the influences of illumination source-s fluctuations and dyes- photo-bleaching can be eliminated to some degree.