  An analytical model of a parabolic screen illuminating a black hole is
proposed. This allows to avoid naturally the appearance of edge effects
associated with photons moving along the plane of the screen. The temperature
distribution along the radius of the screen corresponds to that for a
relativistic disk (Novikov-Thorne disk). It is shown that the structure of the
emerging black hole shadow differs significantly from the case when the photon
source is a remote screen, since in the model considered, the photons subjected
to strong gravitational lensing of the black hole are emitted by the "back
side" of the screen, which would not be visible in the absence of a black hole.
In the thin screen approximation, the shadow of a Schwarzschild black hole has
been constructed in cases when the angle between the axis of symmetry of the
illuminating screen and the direction towards the observer is 5, 30, 60, and 80
degrees. For the Kerr black hole, images are shown for angles of 60 and 80
degrees.
