海水盐度和温度实时检测的新型光纤传感器研究

Novel Optical Fiber Sensor for Simultaneous Undersea Temperature and Salinity Measurement

提出了一种新颖的用于海水温度和盐度同时实时探测的光纤传感器系统。分别利用半导体材料吸收光谱的临界极限值随温度变化发生移动而导致出射光强改变的特性和待测液体盐度变化引起传输光折射角改变导致接收端光线偏移的性质 ,通过反射式的结构设计和线阵排列的接收光纤将信号传输至海面以上 ,并由CCD实现对光强峰值信号及其偏移量的采集。传感器由一直角棱镜、本征GaAs单晶体薄片、装有参考液和待测液的水槽、接收光纤阵列等部分组成。

A new optical fiber sensor developed for simultaneously measuring the seawater temperature and salinity is described. The sensor respectively exploits the displacement of the optical absorption edge in semiconductors under the influence of temperature variation as a result of temperature induced energy shifting of conduction band extrema, and the beam deviation caused by the optical refraction at the receiving end face due to the salinity of seawater. The measured optical signals are reflected and transmitted through a sequentially linear arranged fibers array, and then the light intensity peak value and its deviant are detected by a charge coupled device (CCD). The sensor probe is composed of an intrinsically pure GaAs single crystal,a right angle prism, a partitioned water cell, the emitting fiber with an attached self focused lens and the linear arranged receiving fibers array. Theoretical analysis and simulations verify the feasibility of the proposed system.