A New Strategy for Deep Wide‐Field High‐Resolution Optical Imaging

We propose a new strategy for obtaining enhanced resolution (FWHM = 0.12arcsec) deep optical images over a wide field of view. As is well known, thistype of image quality can be obtained in principle simply by fast guiding on asmall (D = 1.5m) telescope at a good site, but only for target objects whichlie within a limited angular distance of a suitably bright guide star. For highaltitude turbulence this 'isokinetic angle' is approximately 1 arcminute. Witha 1 degree field say one would need to track and correct the motions ofthousands of isokinetic patches, yet there are typically too few sufficientlybright guide stars to provide the necessary guiding information. Our proposedsolution to these problems has two novel features. The first is to useorthogonal transfer charge-coupled device (OTCCD) technology to effectivelyimplement a wide field 'rubber focal plane' detector composed of an array ofcells which can be guided independently. The second is to combine measuredmotions of a set of guide stars made with an array of telescopes to provide theextra information needed to fully determine the deflection field. We discussthe performance, feasibility and design constraints on a system which wouldprovide the collecting area equivalent to a single 9m telescope, a 1 degreesquare field and 0.12 arcsec FWHM image quality.