Optical imaging for Goaly3 Multi-mirror telescope system

In order to better investigate the imaging characteristics of the sparse aperture optical system, a Goaly3 multi-mirror telescope (MMT) is designed and its prototype is manufactured. The telescope adopts the Cassegrain structure. Its primary mirror is composed of three sub-mirrors with the same diameters of 80 mm. The optical imaging of the telescope is conducted in the experiment. It is shown that the experimental results are consistent with the theoretical analysis. The practical cutoff frequency of the telescope is 70.7 lp/mm with the corresponding diffraction limit being 74 lp/mm. The quality and contrast of the imaging results are improved greatly through image restoration.