【摘要】 为了提高光纤Bragg光栅(FBG)的温度灵敏度,设计了一种双金属FBG温度增敏装置。增敏装置利用不同金属热胀系数的差异和巧妙的增敏结构,大幅度提高了FBG的温度灵敏度。从理论分析了增敏结构的增敏原理,并给出了波长温度响应关系式。使用此增敏装置制作了一种高灵敏度的FBG温度传感器。为了保证FBG长期固定的稳定性,在制作传感器时使用了低熔点玻璃焊接工艺。实验中,测得增敏FBG温度传感器的温度灵敏度系数达到345.9 pm/℃,是裸FBG的35倍,线性度为0.999 89。对增敏前和增敏后的FBG反射谱进行了对比,结果表明,增敏装置对FBG反射光的功率和反射谱的形状影响很小。对增敏FBG温度传感器的稳定性进行了测试,并用裸FBG作为参考,测试结果显示,增敏装置对FBG的稳定性没有造成影响。更多还原

【Abstract】 In order to enhance the temperature sensitivity of fiber Bragg grating(FBG),a bi-metal FBG temperature sensitivity enhancing device is designed.Based on the difference between the thermal characteristics of two different metals and a smart sensitivity enhancing structure,the device can enhance the temperature sensitivity of FBG obviously.The characteristics of the device are analyzed theoretically and the wavelength to temperature response is calculated.Highly temperature-sensitive FBG sensors are produced by fixing FBG on the temperature sensitivity enhancing device.To make the fixed point stable in a long period,the FBG is fixed by using low melted glass technology.The highly temperature-sensitive FBG sensor is tested and the result indicates that the temperature sensitivity is increased to 345.9 pm/℃,as 35 times of that of bare FBG,and the linear degree is 0.999 89.The temperature sensitivity enhancing device has little impact on the power of reflected light wave and the shape of reflected spectrum of the highly temperature-sensitive FBG sensor,compared with the unpackaged FBG.A stability test is carried on and the result indicates that the stability of the highly sensitive FBG sensor is nearly the same as that of the bare FBG in a long period.更多还原