People involved at OAB: Diolaiti, Lombini
MAD is the acronym of Multi-Conjugate Adaptive Optics Demonstrator.
It is an adaptive optics prototype to be installed on a VLT Unit Telescope,
designed and built in the framework of a collaboration among ESO, two
INAF Observatories (Arcetri and Padova) and the Faculdade de Ciencias de
Universidade de Lisboa (Portugal). The main purpose of this prototype
is the demonstration of the multi-conjugate adaptive optics technique,
which has been proposed to overcome the anisoplanatic effects typical of
the single-conjugate adaptive optics. This goal is realized by means of
several deformable mirrors (two in the case of MAD), conjugated to different
altitudes and driven by a control system which collects the information on
the atmospheric turbulence using several reference stars, in order to
reconstruct a kind of three-dimensional mapping of the turbulence.
Two different wavefront sensing techniques are implemented in MAD, namely
star-oriented and layer-oriented. A very interesting feature of the
latter approach is the possibility to combine optically the light of even
very faint stars, thus improving the sky coverage with natural guide stars
only. The 2
field of view corrected by MAD is imaged onto a
cryogenic infrared camera.
The INAF partners are in charge of the design and construction of the layer-oriented wavefront sensor. In particular, concerning the people involved at OAB, Emiliano Diolaiti has worked mainly on the optical design, on the procurement of the optical components and on the system performance analysis; Matteo Lombini on the laboratory integration and on the study of the science cases, with particular emphasis on deep field surveys of extra-galactic objects.