  We report a ground X-ray calibration of two X-ray telescope prototypes at the
PANTER X-ray Test Facility, of the Max-Planck-Institute for Extraterrestrial
Physics, in Neuried, Germany. The X-ray telescope prototypes were developed by
the Institute of Precision Optical Engineering (IPOE) of Tongji University, in
a conical Wolter-I configuration, using thermal glass slumping technology.
Prototype #1 with 3 layers and Prototype #2 with 21 layers were tested to
assess the prototypes' on-axis imaging performance. The measurement of
Prototype #1 indicates a Half Power Diameter (HPD) of 82" at 1.49 keV. As for
Prototype #2, we performed more comprehensive measurements of on-axis angular
resolution and effective area at several energies ranging from 0.5-10 keV. The
HPD and effective area are 111" and 39 cm^2 at 1.49 keV, respectively, at which
energy the on-axis performance of the prototypes is our greatest concern.
