The LATT way towards large active primaries for space telescopes

Year: 2016

Authors: Briguglio R., Arcidiacono C., Xompero M., Lisi F., Riccardi A., Biasi R., Patauner C., Gallieni D., Lazzarini P., Tintori M., D’Amato F., Pucci M., Duò F., Vettore C., Zuccaro Marchi A.

Autors Affiliation: INAF Osservatorio Astrosico, Arcetri L. Enrico Fermi 5, Firenze, 50125, Italy; Microgate, Via Stradivari 4, Bolzano, 39100, Italy; ADS-International, via Roma 87, Valmadrera (LC), 23868, Italy; CNR-INO, L.go E. Fermi 6, Firenze, 50125, Italy; OHB CGS, Compagnia Generale per Lo Spazio, Italy; ESA, ESTEC, Keplerlaan 1, Noordwijk, NL-2200 AG, Netherlands

Abstract: The Large Aperture Telescope Technology (LATT) goes beyond the current paradigm of future space telescopes, based on a deformable mirror in the pupil relay. Through the LATT project we demonstrated the concept of a low-weight active primary mirror, whose working principle and control strategy benefit from two decades of advances in adaptive optics for ground-based telescopes. We developed a forty centimeter spherical mirror prototype, with an areal density lower than 17 kg/m2, controlled through contactless voice coil actuators with co-located capacitive position sensors. The prototype was subjected to thermo-vacuum, vibration and optical tests, to push its technical readiness toward level 5. In this paper we present the background and the outcomes of the LATT activities under ESA contract (TRP programme), exploring the concept of a lightweight active primary mirror for space telescopes. Active primaries will open the way to very large segmented apertures, actively shaped, which can be lightweight, deployable and accurately phased once in flight.

Conference title: SPIE Astronomical Telescopes + Instrumentation
Place:

KeyWords: Active optics; Deformable mirrors; Low-weight primary mirrors; Space telescopes; Wavefront correctors; Capacitive sensors; Deformation; Laser pulses; Millimeter waves; Mirrors; Space telescopes; Vision aids, Active Optics; Control strategies; Deformable mirrors; Ground-based telescopes; Large aperture telescopes; Primary mirrors; Voice coil actuators; Wavefront corrector, Adaptive optics