  We show that an initially unpolarized electron flow acquires spin
polarization after passing through a lateral barrier in two-dimensional (2D)
system with spin-orbit interaction (SOI) even if the current is directed
normally to the barrier. The generated spin current depends on the distance
from the barrier. It oscillates with the distance in the vicinity of the
barrier and asymptotically reaches a constant value. The most efficient
generation of the spin current (with polarization above 50%) occurs, when the
Fermi energy is near the potential barrier maximum. Since the spin current in
SOI medium is not unambiguously defined we propose to pass this current from
the SOI region into a contacting region without SOI and show, that the spin
polarization loss under such transmission can be negligible.
