HARMONI at ELT: cooled environment for focal plane relay optics and guide star sensors; design ahead of FDR

Tom Louth; David Montgomery; Stuart Watt; William Cochrane; Fraser Clarke; Kjetil Dohlen; William Humphreys

doi:10.1117/12.2627706

29 August 2022 HARMONI at ELT: cooled environment for focal plane relay optics and guide star sensors; design ahead of FDR

Tom Louth, David Montgomery, Stuart Watt, William Cochrane, Fraser Clarke, Kjetil Dohlen, William Humphreys

Author Affiliations +

Proceedings Volume 12184, Ground-based and Airborne Instrumentation for Astronomy IX; 121842N (2022) https://doi.org/10.1117/12.2627706
Event: SPIE Astronomical Telescopes + Instrumentation, 2022, Montréal, Québec, Canada

Conference Poster

Abstract

The Natural Guide Star Sensors (NGSS) system of HARMONI provides wavefront and image stabilisation sensing for each of the observing modes of the instrument. The Focal Plane Relay System (FPRS) relays and redirects the telescope beam from the ELT Prefocal Station (PFS) to the NGSS and spectrograph. To limit thermal background and to ensure the required stability, the sensors and optics are contained in a dry gas environment stabilized at -15 degrees Celsius. Achieving this cooled, dry environment requires an insulated enclosure, cooling system and dry air flushing system. These measures present certain novel challenges; the design solutions are described here.

Citation Download Citation

Tom Louth, David Montgomery, Stuart Watt, William Cochrane, Fraser Clarke, Kjetil Dohlen, and William Humphreys "HARMONI at ELT: cooled environment for focal plane relay optics and guide star sensors; design ahead of FDR", Proc. SPIE 12184, Ground-based and Airborne Instrumentation for Astronomy IX, 121842N (29 August 2022); https://doi.org/10.1117/12.2627706

ACCESS THE FULL ARTICLE

INSTITUTIONAL
Select your institution to access the SPIE Digital Library.

SELECT YOUR INSTITUTION

PERSONAL
Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.

PERSONAL SIGN IN

No SPIE Account? Create one

PURCHASE THIS CONTENT

SUBSCRIBE TO DIGITAL LIBRARY

50 downloads per 1-year subscription

Members: $195

Non-members: $335 ADD TO CART

25 downloads per 1 - year subscription

Members: $145

Non-members: $250 ADD TO CART

PURCHASE SINGLE ARTICLE

Includes PDF, HTML & Video, when available