Characterizing the reflectance near the Brewster angle: a   Pade-approximant approach
  We characterize the reflectance peak near the Brewster angle for both an interface between two dielectric media and a single slab. To approach this problem analytically, we approximate the reflectance by a first-order diagonal Pad\'e. In this way, we calculate the width and the skewness of the peak and we show that, although they present a well-resolved maximum, they are otherwise not so markedly dependent on the refractive index. 
Teresa Yonte and Luis L. Sanchez-Soto