FRIDA (inFRared Imager and Dissector for the Adaptive optics system of the Gran Telescopio Canarias) has been designed as a cryogenic and diffraction limited instrument that will offer broad and narrow band imaging and integral field spectroscopy (IFS). Both, the imaging mode and IFS observing modes will use the same Teledyne 2Kx2K detector. This instrument will be installed at Nasmyth B station, behind the GTC Adaptive Optics system (GTCAO). FRIDA will provide the IFS mode using a 30 slices Integral Field Unit (IFU). This IFU design is based on the University of Florida FISICA where the mirror block arrays are diamond turned on monolithic metal blocks. The FRIDA IFU is of the slicer type; conformed mainly by 3 mirror blocks with 30 spherical mirrors each. It also has a Schwarzschild relay based on two off axis spherical mirrors and an afocal system of two parabolic off axis mirrors. Including two insertion mirrors the IFU holds 96 metal mirrors. All the mirrors have been manufactured by diamond turning techniques on monolithic blocks of aluminum 6061-T6 coated by a Nickel alloy. Except for the Schwarzschild relay and the insertion mirrors, 92 mirrors were manufactured by Corning in Keene NH, USA. The different blocks and mirrors are mounted on an opto-mechanical support that ensures the image quality and integrity of the complete IFU. In this work advances on the manufacturing of the FRIDA IFU components are described. Furthermore, the mirror blocks individual verification tests and are also described.

Date Published: 28 July 2014
PDF: 8 pages
Proc. SPIE 9151, Advances in Optical and Mechanical Technologies for Telescopes and Instrumentation, 91514N (28 July 2014); doi: 10.1117/12.2057442

Published in SPIE Proceedings Vol. 9151:
Advances in Optical and Mechanical Technologies for Telescopes and Instrumentation
Ramón Navarro; Colin R. Cunningham; Allison A. Barto, Editor(s)