  Light scattering by Josephson vortices is theoretically predicted. An
experimental set-up for the observation of the effect is proposed. The magnetic
field should be parallel to the CuO_2 layers and the crystal surface. The
falling light should be at grazing angles, and the Bragg scattering must be
almost backscattering. The distance between the columns of the Josephson
vortices must be slightly smaller than the light-wavelength. The surface should
be very clean and flat in order light scattering by surface terraces and
surface roughness to give the relatively small background.
