HARMONI at ELT: pre-optics optical design at FDR

Cagigas, M. A.; García-Lorenzo, B.; Alonso, A.
Bibliographical reference

Society of Photo-Optical Instrumentation Engineers (SPIE) Conference Series

Advertised on:
6
2024
Number of authors
3
IAC number of authors
3
Citations
0
Refereed citations
0
Description
HARMONI is the first light visible and near-IR integral field spectrograph for the Extremely Large Telescope. It covers a large spectral range from 470nm to 2450nm with resolving powers from 3300 to 18000 and spatial sampling from 60mas to 4mas. It can operate in two Adaptive Optics modes (including a High Contrast capability) - or with Non Adaptive Optics. The project is preparing for Final Design Reviews. In this paper, we present the optical design of the Pre-Optics for Final Design Reviews, 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 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.