The optics of Galileo Telescope: alignment and active optics preliminary results

After a deep series of optical tests the Galileo Telescope has finally reached its optimum configuration. A first rough alignment of the three main mirrors has been obtained using alignment telescopes and targets, in order to define the position of the optical axes. The following step has been to take intra-focal and extra-focal pupil images to introduce fine correction on the positioning of the secondary mirror and reduce defocus, spherical and coma. A campaign of Shack Hartmann analysis was then performed. The Antares wavefront sensor was mounted at Nasmyth B arm and several nights were spent in order to test the active optics system performances by introducing known aberrations. The residual aberration from the previous raw alignment was also corrected. Both these tests show that the system is able to work as expected.