The MICADO first light imager for the ELT: he detector positioning system of MICADO

The Detector Positioning System (DPS) is a cryogenic mechanism operating at 82 K installed in the cryostat of the Multi- AO Imaging Camera for Deep Observations (MICADO) at the Extremely Large Telescope (ELT). The DPS mechanism will be exclusively utilized during the alignment and test phase. Upon completing the test phase, it will be mechanically locked at the best pre-determined focus so that it cannot be moved during the observation period. The DPS has been conceptualized as a fixed and reproducible interface to the Main Bench Structure in the MICADO cryostat and as an adjustable unit containing the Detector Array mounted on the DPS frame installed on a linear guide on the base plate. A cryogenic linear actuator further acts as the linear guide during the alignment phase to bring the focal plane array into focus.