MICADO, a Multi-AO Imaging Camera for Deep Observations, is a first light imager for the European Large Telescope (ELT). It is being designed and built by a consortium of partners from 6 different countries across Europe and led by the Max Planck Institute for Extraterrestrial Physics (MPE) in Garching. The European Southern Observatory (ESO) is responsible for delivering the near infrared detector subsystem to the instrument. This subsystem includes nine Hawaii-4RG-15 (H4RG-15) near infrared detectors (2.5μm cut-off) mounted in a compact 3x3 mosaic at the heart of the instrument. They will operate at a nominal temperature of 82K using an array of cryogenic preamplifiers located at the back of the focal plane plate, close to the detectors. This paper presents an overview of this detector subsystem, including the measured performance of two of the H4RG-15 science detectors already characterised in a custom-built test facility at ESO. Special readout modes have been developed for the instrument and for AO corrections to one of the ELT mirrors and these are described. The design of the focal plane, its thermal analysis and the focal plane flatness measurement system being setup at ESO is also presented. This paper also provides a brief description of the new detector controllers (NGCII) being developed at ESO for all the ELT and future VLT (Very Large Telescope) science detector systems and presents the specific controller configuration which must be implemented for the MICADO detectors.
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