  Existence and uniqueness of the scattering solutions is proved for a class of
bounded rough obstacles which is much larger than the class of Lipschitz
obstacles. Integral equations method is not used. The approach is based on the
representation theorem for selfadjoint operators via closed symmetric quadratic
forms and on the limiting absorption principles. For the Dirichlet boundary
condition no assumptions on the smoothness of the boundary are needed, for the
Neumann boundary condition and the Robin boundary condition some assumptions on
the smoothness of the boundary are needed.
