Integration and first results of the CAMCAO NIR camera

Author(s)
António Amorim, Jorge Lima, João Alves, José Rebordão, José Pinhão, Luis Gurriana, Alexandre Cabral, Enrico Marchetti, Johann Kolb, Sebastian Tordo, Gert Finger, Jean-Louis Lizon, Filipe Duarte Santos, Rui Ferreira Marques, Rui Alves, Rui Barros
Abstract

This paper presents the integration and first results for the CAMCAO NIR camera. The camera was built for the ESO Multi-conjugate Adaptive optics Demonstrator, where it is presently operating, to evaluate the feasibility of this Adaptive Optics technique. On a second phase it will work directly at the Nasmyth focus of the VLT. CAMCAO is a high resolution, wide field of view NIR camera, that is using the 2k×2k HgCdTe HAWAII- 2 infrared detector from Rockwell Scientific, controlled by the ESO IRACE system. The camera operates in the near infrared region between 1.0 μm and 2.5 μm wavelength using an eight position filter wheel with J, H, K', K-continuum and Brγ filters. Both the integration experience and the results obtained in the mechanical, vacuum, cryogenics and optical tests are presented, including all relevant parameters in the ESO specifications. The requirement of mechanical stiffness together with light weight was achieved yielding a total weight of less than 90 Kg. The camera fulfills both cryogenic and vacuum stability requirements. The temperature within the detector is maintained at 80K by an accurate control loop, ensuring mK stability, after cooling down the detector at a rate kept below 0.5 K/min. The optical performance tests were made using a Fizeau interferometer both for the individual optical components and complete setup. The infrared optical validation measurements were performed by re-imaging a point source in the camera focal plane and measuring the PSF with the detector. The computed Strehl ratio reached 95% in the central region of the FoV, with values larger than 90% in a area covering 88% of the focal plane.

Organisation(s)
Department of Astrophysics
External organisation(s)
European Southern Observatory (Germany), Universidade de Lisboa, National Institute of Engineering, Technology and Innovation (INETI), Universidade de Coimbra
Journal
Proceedings of SPIE
Volume
6269
Pages
57
ISSN
0277-786X
DOI
https://doi.org/10.1117/12.671746
Publication date
06-2006
Peer reviewed
Yes
Austrian Fields of Science 2012
103004 Astrophysics
Portal url
https://ucris.univie.ac.at/portal/en/publications/integration-and-first-results-of-the-camcao-nir-camera(a9433550-6fe4-42bf-b903-ddcff3a9704a).html