Starting from a scattering model the transmission coefficient of elect
rons for oblique angle of incidence is derived. The decrease of the tr
ansmitted fraction is described by the backscattering of electrons and
the energy loss caused by the decreasing mean free path. The angular-
and energy-distribution of electrons is replaced by the most probable
angle and mean energy. A comparison with other models and measurement
s valid for normal incidence is performed. The altered transmission ch
aracteristics by tilting the sample are verified by comparison with re
sults from Monte Carlo simulations and results from Neubert and Rogasc
hewski, which are based on measurements. An analytical expression for
the transmission law is obtained.