Freeform Wide Field-of-View Spaceborne Imaging Telescope: From Design to Demonstrator.

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Wide field-of-view imaging optics offer a huge potential for space-based Earth observation enabling the capture of global data. Reflective imaging telescopes are often favored, as they do not show chromatic aberrations and are less susceptible to radiation darkening than their refractive counterparts. However, the main drawback of reflective telescopes is that they are limited with respect to field-of-view while featuring large dimensions. We propose the use of freeform optics to maximize the field of view while maintaining diffraction-limited image quality and minimizing system dimensions. In this paper, we present a novel freeform wide field-of-view reflective telescope, starting from the optical design, and continuing to tolerancing analysis and manufacture, towards a proof-of-concept demonstrator. The novel telescope features a full field-of-view of 120° while showing an exceptional spatial resolution of 2.6 km and fitting within 1 CubeSat unit. To the best of our knowledge, this is the widest field-of-view that has ever been realized for a space-based telescope, nearly reaching Earth observation from limb to limb from an altitude of about 700 km. We hope this design paves the way for future space missions enabling improved Earth observation and leading to enhanced monitoring of climate and climate change.
Original languageEnglish
Article number8233
Pages (from-to)1-4
Number of pages4
Issue number21
Publication statusPublished - 27 Oct 2022

Bibliographical note

Funding Information:
The work of L. Schifano was funded by the Solar-Terrestrial Center of Excellence (STCE). The work was supported by Interreg (Fotonica Pilootlijnen, NWE758); Flanders Make; Methusalem and Hercules Foundations and the OZR of the Vrije Universiteit Brussel (VUB).

Publisher Copyright:
© 2022 by the authors.

Copyright 2022 Elsevier B.V., All rights reserved.


  • Earth observationclimate monitoringdemonstratorfreeform opticsreflective opticsspace instrumentationtelescopewide field-of-view

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