Translator Disclaimer
25 July 2008 Manufacturing and verification of ZnS and Ge prisms for the JWST MIRI imager
Author Affiliations +
The JWST Mid-Infrared Instrument (MIRI) is designed to meet the JWST science requirements for mid-IR capabilities and includes an Imager MIRIM provided by CEA (France). A double-prism assembly (DPA) allows MIRIM to perform low-resolution spectroscopy. The MIRIM DPA shall meet a number of challenging requirements in terms of optical and mechanical constraints, especially severe optical tolerances, limited envelope and very high vibration loads. The University of Cologne (Germany) and the Centre Spatial de Liege (Belgium) are responsible for design, manufacturing, integration, and testing of the prism assembly. A companion paper (Fischer et al. 2008) is presenting the science drivers and mechanical design of the DPA, while this paper is focusing on optical manufacturing and overall verification processes. The first part of this paper describes the manufacturing of Zinc-sulphide and Germanium prisms and techniques to ensure an accurate positioning of the prisms in their holder. (1) The delicate manufacturing of Ge and ZnS materials and (2) the severe specifications on the bearing and optical surfaces flatness and the tolerance on the prism optical angles make this process innovating. The specifications verification is carried out using mechanical and optical measurements; the implemented techniques are described in this paper. The second part concerns the qualification program of the double-prism assembly, including the prisms, the holder and the prisms anti-reflective coatings qualification. Both predictions and actual test results are shown.
© (2008) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
Laurence Rossi, Jean-François Jamoye, Etienne Renotte, Emmanuel Mazy, Jean-Yves Plesseria, Nathalie Ninane, Marc Wielandts, Sebastian Fischer, Christian Straubmeier, Jean-Louis Augueres, Didier Dubreuil, Jérôme Amiaux, Sébastien Poupar, and Samuel Ronayette "Manufacturing and verification of ZnS and Ge prisms for the JWST MIRI imager", Proc. SPIE 7018, Advanced Optical and Mechanical Technologies in Telescopes and Instrumentation, 701823 (25 July 2008); doi: 10.1117/12.789148;


A Visual Grading Method For Zinc Selenide, And New Surface...
Proceedings of SPIE (December 08 1983)
Infrared Window Manufacturing Technology
Proceedings of SPIE (January 18 1984)
Mounting MIRI's double prism
Proceedings of SPIE (June 14 2006)
The JWST MIRI double-prism: design and science drivers
Proceedings of SPIE (July 11 2008)

Back to Top