Bibcode
Cagigas, M. A.; Hernandez, E.; Rasilla, J. L.; Mediavilla, E.; García-Lorenzo, B.; Herreros, J. M.; Gigante, J. V.; Rodriguez, L. F.; Bryson, I.; Schnedtler, M.; Clarke, F.; Tecza, M.; Thatte, N.
Bibliographical reference
Proceedings of the SPIE, Volume 10702, id. 107029H 13 pp. (2018).
Advertised on:
7
2018
Citations
0
Refereed citations
0
Description
HARMONI is a visible and near-infrared (0.5 to 2.45 μm) integral
field spectrograph, providing the E-ELT's core spectroscopic capability,
over a range of resolving powers from R (λ/Δλ)
3500 to 18000. The instrument provides simultaneous spectra of
˜32000 spaxels arranged in a sqrt(2):1 aspect ratio contiguous
field. The pre-optics take light entering the science cryostat (from the
telescope or calibration system), reformatting and conditioning to be
suitable for input for the rest of the instrument. This involves many
functions, mainly relaying the light from the telescope focal plane to
the integral field unit (IFU) focal plane via a set of interchangeable
scale changing optics. The pre-optics also provides components including
a focal plane mask wheel, cold pupil masks, spectral order sorting
filters, a fast shutter, and a pupil imaging capability to check
telescope/instrument pupil alignment. In this paper, we present the
optical design of the HARMONI pre-optics at Preliminary Design Review
and, in particular, we detail the differences with the previous design
and the difficulties salved to the Preliminary Design Review.