  The aim of our work was to study the spatial structure of inhomogeneities of
interstellar plasma in the directions of five pulsars: B0823+26, B0834+06,
B1237+25, B1929+10, and B2016+28. Observations of these pulsars were made with
RadioAstron space-ground radio interferometer at 324 MHz. We measured the
angular size of the scattering disks to be in range between 0.63 and 3.2 mas.
We determined the position of scattering screens on the line of sight.
Independent estimates of the distances to the screens were made from the
curvature of parabolic arcs revealed in the secondary spectra of four pulsars.
The model of uniform distribution of inhomogeneities on the line of sight is
not suitable. According to the results, we came to the conclusion that
scattering is mainly produced by compact plasma layers and the uniform model of
inhomogeneties distribution on the line of sight in not applicable.
