采用射频溅射方法制备了贵金属银薄膜样品.通过椭圆偏振光谱方法在1.5～4.5eV光子能量区测量获得了复介电函数和复折射率.针对3个不同波长的复折射率常数，对于光从大气入射到金属银边界，以及从金属银入射到大气边界的情况进行了具体模拟计算和分析，发现即使在平行金属膜条件下，光在大气一侧的出射角也不等于初始入射角，并且与波长、光学常数和入射角等有关的等效折射率常数和折射角均为正值，在整个光谱区不改变符号，与实验观察的结果不相符合.实例计算所揭示的这些涉及到光在金属中的传输特性仍有待于更多的实验和理论研究.

The noble metal Ag film sample was prepared by the RF (radio frequency) sputtering method. The complex dielectric function and the complex refractive index of the thick Ag film sample were measured by the spectroscopic ellipsometric method in the 1.5 - 4.5 eV photon energy region. The light refractions at the Ag/air interface for a plane film structure were analytically calculated at three different wavelengths. From the calculation, it was found that the refraction angle at the air side is not equal to the initial incidence angle, which is against the experimental observations. The pseudo refractive index and the real refractive angle related to the wavelength, optical constant and incidence angle are always positive in the whole spectrum range. The results given in this work show that more experimental and theoretical studies will be required to understand the properties of light propagation at the metal interface in the future.