Assembly, alignment, and testing of the DECam wide field corrector optics

The DES project is a 5 year imaging survey of the southern sky using the 4m Blanco Telescope at the Cerro Tololo International Observatory in Chile. A new wide field camera with a 2.2 degree diameter field of view has been built to undertake this survey. The alignment of the large lenses for this camera poses a significant challenge as they have to be aligned to a tolerance of ±50 micrometers. This paper presents the assembly and alignment process of the full optical system along with the test results. Also included is the predicted imaging performance from the as-built system.

[1]  B. Flaugher The Dark Energy Survey , 2005 .

[2]  T. Abbott,et al.  Preliminary optical design for a 2.2 degree diameter prime focus corrector for the Blanco 4 meter telescope , 2006, SPIE Astronomical Telescopes + Instrumentation.

[3]  A. Stefanik,et al.  Design and status of the optical corrector for the DES survey instrument , 2008, Astronomical Telescopes + Instrumentation.

[4]  K. Honscheid,et al.  The Dark Energy Camera (DECam) , 2008, Astronomical Telescopes + Instrumentation.

[5]  Brenna L. Flaugher The Dark Energy Survey Camera , 2012 .