  Magnetic domain walls in thin films can be well analyzed using polarized
neutron reflectometry. Well defined streaks in the off-specular spin-flip
scattering maps are explained by neutron refraction at perpendicular N\'{e}el
walls. The position of the streaks depends only on the magnetic induction
within the domains, whereas the intensity of the off-specular magnetic
scattering depends on the spin-flip probability at the domain walls and on the
average size of the magnetic domains. This effect is fundamentally different
and has to be clearly distinguished from diffuse scattering originating from
the size distribution of magnetic domains. Polarized neutron reflectivity
experiments were carried out using a $^3$He gas spin-filter with a analyzing
power as high as 96% and a neutron transmission of approx 35%. Furthermore, the
off-specular magnetic scattering was enhanced by using neutron resonance and
neutron standing wave techniques.
