A method is proposed for determining the optical characteristics of glass plates after physicochemical surface treatment by measuring spectra of ellipsometric angles at incidence angles equal to Brewster’s angle. The dispersion dependence of the refractive index could be determined and the surface layer thickness during the plate manufacturing process could be estimated using the coordinates of the ellipsometric-angle spectral minima. Refractive-index spectra calculated by the Brewster formula for KU-1 optical quartz plates in the non-absorbing region were in satisfactory agreement with spectra determined by numerical methods in the DeltaPsi2 software of a UVISEL 2 spectral ellipsometer (Horiba). The relative error of a refractive-index determination of the quartz plates by the proposed method was ≤0.1%.

中文翻译：

---

光谱椭偏测定的布鲁斯特角平行石英板的光学特性

提出了一种通过在与布鲁斯特角相等的入射角下测量椭圆角的光谱来确定经过物理化学表面处理的玻璃板的光学特性的方法。可以使用椭偏角光谱最小值的坐标来确定折射率的色散依赖性，并可以估算板制造过程中的表面层厚度。通过Brewster公式计算的非吸收区KU-1光学石英板的折射率光谱与通过UVISEL 2光谱椭圆仪（Horiba）的DeltaPsi2软件中的数值方法确定的光谱令人满意。所提出的方法测定石英板的折射率的相对误差≤0.1％。