利用偏振光技术计算海水密度的深入研究

Further Study on Calculating the Density of Seawater with Polarized Light Technology

在可见光波段范围内,利用折射率可以建立偏振度与海水密度之间的函数关系,但是计算的海水密度误差较大。为了更加精确的计算海水密度,以色散理论为基础,确定计算海水密度最优波段。实验中以大连湾与月芽湾海水为研究对象,利用USB2000光谱仪测量海水偏振光谱并计算出偏振度,用反向迭代法找出与实际密度对应的偏振度误差较小的波段,即计算海水密度的最优波段。结果表明,不同密度的海水在不同入射角度计算密度的最优波段不同,在(650±2)～(670±2)nm范围内具有较高的精度。在最优波段范围内计算的精度高,使得偏振信息计算海水密度在遥感技术中的实际应用更进一步。

The function relation between polarization and the density of seawater at the range of visible waveband can be established by index of refraction,but there is a great calculation error.In order to calculate the density of seawater more accurately,the best waveband of calculating the density of seawater was determined based on dispersion theory.Seawater from Dalian Bay and Yueya Bay was used as study objects,and USB2000 spectrometer was used to measure the polarized spectrum of seawater,and then its polarization was calculated.Iterative inversion was used to find out the waveband which has the smallest polarization errors that match along with the actual density,which means the optimal waveband of calculating the density of seawater.The results show that seawater with different densitis has different optimal wavebands to calculate the densities at different incident angles.That is to say,the calculation of density has a higher accuracy at the range of（650±2）^（670±2）nm waveband.A further step of using polarization information to calculate the density of seawater in the practical application of remote sensing technology is showed.