Title :
The optics of Galileo Telescope: alignment and active optics preliminary results
Author :
Adriano, Ghedina ; Fabio, Bortoletto ; Enrico, Marchetti ; Daniele, Gardiol ; Roberto, Ragazzoni ; Claudio, Pernechele
Author_Institution :
Centro Galileo Galilei, Santa Cruz de La Palma, Spain
Abstract :
After a 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 next 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 performance 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
Keywords :
aberrations; adaptive optics; astronomical telescopes; mirrors; physical instrumentation control; position control; wavefront sensors; Antares wavefront sensor; Galileo Telescope; Nasmyth B arm; Shack Hartmann analysis; aberrations; active optics; alignment; coma; defocus; extra-focal pupil images; fine correction; intra-focal pupil images; optical axes; optimum configuration; secondary mirror; Actuators; Image sensors; Mechanical variables measurement; Mirrors; Optical interferometry; Optical sensors; Performance analysis; Performance evaluation; System testing; Telescopes;
Conference_Titel :
Instrumentation and Measurement Technology Conference, 1999. IMTC/99. Proceedings of the 16th IEEE
Conference_Location :
Venice
Print_ISBN :
0-7803-5276-9
DOI :
10.1109/IMTC.1999.777050