The ELT/METIS Annular Groove Phase Masks

High-contrast imaging instruments employ coronagraphs to study stellar environments by reducing the glare of stars. The Annular Groove Phase Mask (AGPM), a vector vortex coronagraph, is a valuable tool for achieving high-contrast performance at small angular separations. The METIS project, integrating multiple AGPMs for various LMN spectrum wavelengths, is currently in its Manufacture, Assembly, Integration, and Test (MAIT) phase. The performance of the METIS AGPMs is evaluated on two test benches: VODCA at the University of Liège for L- and M-band AGPMs and a cryogenic testbed at CEA Paris-Saclay for N-band AGPMs. The present study covers manufacturing, testing, centering processes, and coronagraphic performance results for all METIS AGPMs.