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The Space-based multi-band astronomical Variable Objects Monitor (SVOM) is a Chinese -French satellite mission due to be launched in the summer of 2022. It is composed of four instruments: ECLAIRs, for detecting X-ray and gamma-ray transients (4-250 keV); GRM, a gamma-ray spectrometer (15 keV-5 MeV); VT, a visible telescope and the Microchannel X-ray Telescope (MXT). The MXT's main goal is to precisely localize, and spectrally characterize X-ray afterglows of Gamma-Ray Bursts. The MXT is a narrow-field-optimised lobster eye X-ray focusing telescope comprising an array of 25 square Micro Pore Optics (MPOs), with a detectorlimited field of view of ∼1 square degree, working in the energy band 0.2-10 keV. The SVOM qualification model (QM) MXT optic (MOP) was designed and built at the University of Leicester, and is the first complete, lobster eye optic to be X-ray tested. We present results from the PANTER facility (MPE), where a full calibration of the QM MOP was carried out. The response of the optic was studied at seven energies from C-K to Cu-K, and the effective area at multiple off-axis angles at each energy was measured. The focal length of the MOP was confirmed and the PSF was studied on and off-axis. In addition, we present details of the modelling and analysis, which was used to calculate the results from the test campaign. The effective area and PSF are in good agreement with the modelling, indicating that the optic is performing as expected.

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Conical Wolter-I geometry is employed for many x-ray telescopes to lower their cost and fabrication difficulty at the expense of angular resolution. Owing to the conic error, the angular resolution of conical Wolter-I geometry is much worse than that of Wolter-I geometry, especially for the telescopes with large diameter. We optimized the conical Wolter-I geometry to significantly improve the angular resolution. We designed a conical Wolter-I geometry with sectioned secondary mirrors. Based on the normal conical Wolter-I geometry, we divided the secondary mirror into two equal sections along the optical axis. In this case, the collecting area was reduced by 5% because of the interval between the two sections. Meanwhile, the conic error was reduced by about 50%, indicating a great improvement in angular resolution. Regarding our improvement in the thermal slumping technique, it is feasible to fabricate sectioned mirrors, thus improving the angular resolution by 50% at the cost of a 5%-reduction in collecting area. In addition, a hybrid geometry, comprising the sectioned and nonsectioned geometries, is proposed as an alternative for x-ray telescopes with a large amount of nested shells, to obtain both a large collecting area and decent angular resolution.