Print Email Facebook Twitter Development of silicon immersed grating for METIS on E-ELT Title Development of silicon immersed grating for METIS on E-ELT Author van Amerongen, A.H. Agocs, T. van Brug, H. Nieuwland, G. Venema, L. Hoogeveen, R.W.M. Publication year 2012 Abstract We have developed the technology to manufacture an immersed grating in silicon for the Mid-infrared E-ELT Imager and Spectrograph, METIS. We show that we can meet the required diffraction-limited performance at a resolution of 100000 for the L and M spectral bands. Compared to a conventional grating, the immersed grating drastically reduces the beam diameter and thereby the size of the spectrometer optics. As diffraction takes place inside the high-index medium, the optical path difference and angular dispersion are boosted proportionally, thereby allowing a smaller grating area and a smaller spectrometer size. The METIS immersed grating is produced on a 150 mm industry standard for wafers and replaces a classical 400 mm echelle. Our approach provides both a feasible path for the production of a grating with high efficiency and low stray light and improves the feasibility of the surrounding spectrometer optics. In this contribution we describe and compare the classical-grating solution for the spectrometer with our novel immersed-grating based design. Furthermore, we discuss the production route for the immersed grating that is based on our long-standing experience for space-based immersed gratings. We use standard techniques from the semiconductor industry to define grating grooves with nanometer accuracy and sub-nanometer roughness. We then use optical manufacturing techniques to combine the wafer and a prism into the final immersed grating. Results of development of the critical technology steps will be discussed. Subject E-ELTEtchingGratingImmersedImmersionMETISSiliconSpectrometerPhysics & ElectronicsOPT - Optics To reference this document use: http://resolver.tudelft.nl/uuid:49392bdf-cc58-48b3-8102-66cb8fd8c09e DOI https://doi.org/10.1117/12.925612 TNO identifier 954328 Publisher SPIE ISBN 9780819491510 ISSN 0277-786X Source Proceedings of SPIE - The International Society for Optical Engineering, Modern Technologies in Space- and Ground-Based Telescopes and Instrumentation II, 1 July 2012 through 6 July 2012 Document type conference paper Files To receive the publication files, please send an e-mail request to TNO Library.