  Combination of Fresnel Zone Plates (FZP) can make excellent telescopes for
imaging in X-rays. We present the results of our experiments with such
telescopes with an X-ray source kept at a distance of 45 feet. We compare the
patterns obtained from experiments with those obtained by our Monte-Carlo
simulations. In simulations, we allow the sources to be at finite distances
(diverging beam) as well as at infinite distances (parallel beam) and show that
the resolution is worsened when the source is nearby. We also present simulated
results for the observation of the galactic center and show that the sources
may be reconstructed with accuracy. We compare the performance of such a
telescope with other X-ray imaging devices used in space-astronomy. The Zone
Plate based instrument has been sent for the first time in a recently launched
KORONAS-FOTON satellite.
