提出了一种高精度测量液体折射率的新方法一“干涉逼近法”.这种方法可以在测量过程中监视被测液体温度不均匀性给测量带来的误差.由于受温度测量的限制,其测量液体折射率的不确定度在1×10~(-6)到4×10~(-5)(2σ)之间,具体值取决于液体折射率的温度系数.

A new interferometric technique for measuring liquid refractive index (RI) with high accuracy has been developed, which is directly traceable to the wavelength of He-Ne laser. The accuracy of this method is improved by increasing the optical path of step. The experiment revealed that the temperature distribution nonuniformity in the liquid limits the practical uncertainty of liquid RI measurement from 1×10-6 to 4×10-5 (2σ) depending on its temperature coefficient although much finer resolution can be easily achieved with this method.