NIRSpec Integral Field Unit
The NIRSpec Integral Field Unit (IFU) flight model on its transport plate. The IFU is roughly the size of a shoe box and weighs less than 1 kg.
The IFU allows for spatially resolved imaging spectroscopy of extended sources. It has a field of view of 3 arcsec × 3 arcsec that will be split into 900 spectra, each corresponding to a tiny spatial element 0.1 arcsec × 0.1 arcsec in size. The IFU uses an image slicer to cut the image in 30 slices that each give rise to 30 contiguous spectra on the detector.