ERIS adaptive optics system design

摘要

The Enhanced Resolution Imager and Spectrograph (ERIS) is the next-generation instrument planned for the Very LargeTelescope (VLT) and the Adaptive Optics facility (AOF). It is an AO assisted instrument that will make use of theDeformable Secondary Mirror and the new Laser Guide Star Facility (4LGSF), and it is planned for the Cassegrain focusof the telescope UT4. The project is currently in its Phase A awaiting for approval to continue to the next phases.The Adaptive Optics system of ERIS will include two wavefront sensors (WFS) to maximize the coverage of theproposed sciences cases. The first is a high order 40x40 Pyramid WFS (PWFS) for on axis Natural Guide Star (NGS)observations. The second is a high order 40x40 Shack-Hartmann WFS for single Laser Guide Stars (LGS) observations.The PWFS, with appropriate sub-aperture binning, will serve also as low order NGS WFS in support to the LGS modewith a field of view patrolling capability of 2 arcmin diameter. Both WFSs will be equipped with the very low read-outnoise CCD220 based camera developed for the AOF. The real-time reconstruction and control is provided by a SPARTA real-time platform adapted to support both WFS modes. In this paper we will present the ERIS AO system in all its main aspects: opto-mechanical design, real-time computer design, control and calibrations strategy. Particular emphasis will be given to the system performance obtained via dedicated numerical simulations.© (2012) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.