Ambient alignment verification of JWST-MIRI

We report on the alignment verification activities using optical visible techniques, and performed at ambient temperature before and after environmental and qualification tests, on the Mid InfraRed Instrument (MIRI), one of the scientific instruments on-board the James Webb Space Telescope (JWST). More specifically, the method developed to measure some of the instrument key parameters, such as pupil shear and focus offset, is explained in details. We describe the chosen approach, the associated common hardware, the initial set-up and alignment, then discuss the measurements themselves and finally the data analysis, before concluding on the successful application of such approach to the optical characterization of the MIRI flight model.