DESI Focal Plane

Instrumentation R&D

Guiding, Focusing & Alignment Cameras for DESI


Guiding, Focusing & Alignment Cameras for DESI

The instrumental contribution to DESI of the Barcelona-Madrid Regional Participation Group, made up of researchers from IFAE, ICE-CSIC, IEEC, CIEMAT and IFT-UAM, has consisted of the design, construction and installation of the complete Guiding, Focusing and Alignment system (GFA).

A picture of the first GFA production camera completed at IFAE, without its filter cover. Credit: IFAE

This system is made up of 10 cameras, each of them installed in one of the focal plane petals of the instrument which, as its name indicates, are in charge of focusing, guiding and aligning the telescope so that the robotic positioners can collect the light from the galaxies under optimum conditions.

DESI Focal Plane
A view of DESI’s fully installed focal plane, which features 5,000 automated robotic positioners, each carrying a fiber-optic cable to gather galaxies’ light. Credit: DESI Collaboration

This contribution has been led by IFAE, where the construction of the cameras has been carried out, with the collaboration of ICE, IEEC, CIEMAT and IFT. In addition, ICE and IEEC have led the production of the software to be able to point the whole instrument properly.

Goup Picture
Members of the Barcelona-Madrid Regional Participation Group that developed DESIs GFAs Credit: IFAE