  The local electromagnetic field distribution over the dielectric (SiC)
surface illuminated by mid-IR light of frequency close to the lattice resonance
was directly mapped with an apertureless scattering near-field optical
microscope. Half of the sample surface was covered with a metal layer, in which
some small $(0.2-10 \mu m)$ holes were formed. It was found, that due to the
eliminating of collective surface polarization effects, the amplitude of the
electromagnetic field becomes several times higher over such holes than over
infinitely open surface of the same dielectric.
