Contactless actuators and pyramid wavefront sensor, the SPLATT concept for space active optics: an overview of the project and the last laboratory results

التفاصيل البيبلوغرافية
العنوان: Contactless actuators and pyramid wavefront sensor, the SPLATT concept for space active optics: an overview of the project and the last laboratory results
المؤلفون: Briguglio, Runa, Xompero, Marco, Scalera, Marcello, Riva, Marco, Del Vecchio, Ciro, Carbonaro, Luca, Arcidiacono, Carmelo, Agapito, Guido, Pinna, Enrico, Terreri, Alessandro, Pedichini, Fernando, Muradore, Riccardo, Tintori, Matteo, Biasi, Daniele Gallieni Roberto, Patauner, Christian, Marchi, Alessandro Zuccaro
سنة النشر: 2023
المجموعة: Astrophysics
مصطلحات موضوعية: Astrophysics - Instrumentation and Methods for Astrophysics
الوصف: In the last few years the concept of an active space telescope has been greatly developed, to meet demanding requirements with a substantial reduction of tolerances, risks and costs. This is the frame of the LATT project (an ESA TRP) and its follow-up SPLATT (an INAF funded R&D project). Within the SPLATT activities, we outline a novel approach and investigate, both via simulations and in the optical laboratory, two main elements: an active segmented primary with contactless actuators and a pyramid wavefront sensor (PWFS) to drive the correction chain. The key point is the synergy between them: the sensitivity of the PWFS and the intrinsic stability of a contactless-actuated mirror segment. Voice-coil, contactless actuators are in facts a natural decoupling layer between the payload and the optical surface and can suppress the high frequency vibration as we verified in the lab. We subjected a 40 cm diameter prototype with 19 actuators to an externally injected vibration spectrum; we then measured optically the reduction of vibrations when the optical surface is floating controlled by the actuators, thus validating the concept at the first stage of the design. The PWFS, which is largely adopted on ground-based telescope, is a pupil-conjugated sensor and offers a user-selectable sampling and capture range, in order to match different use cases; it is also more sensitive than Shack-Hartmann sensor especially at the low-mid spatial scales. We run a set of numerical simulations with the PWFS measuring the misalignment and phase steps of a JWST-like primary mirrors: we investigated the PWFS sensitivity in the sub-nanometer regime in presence of photon and detector noise, and with guide star magnitudes in the range 8 to 14. In the paper we discuss the outcomes of the project and present a possible roadmap for further developments.
Comment: 10 pages, 11 figures. Proceeding of the International Conference on Space Optics ICSO2022, 14th edition, held in Dubrovnik (Croatia) in 3-7 october 2022
نوع الوثيقة: Working Paper
DOI: 10.1117/12.2690310
الوصول الحر: http://arxiv.org/abs/2302.00335Test
رقم الانضمام: edsarx.2302.00335
قاعدة البيانات: arXiv