Near InfraRed Spectrograph (NIRSpec) - grating wheel, camera housing and focal plane assembly view
This view of JWST's Near InfraRed Spectrograph (NIRSpec) shows the grating wheel, camera housing and focal plane assembly.
The grating wheel is the black carousel with yellow squares around the edge. It holds six different gratings, one flat mirror and one double-pass prism. The gratings and the mirror are made from gold-coated Zerodur, a glass ceramic with a low coefficient of thermal expansion. The prism is made from fluorite (CaF2).
The camera housing can be seen to the left of the shot, as a large grey box. The camera, made of 3 mirrors, focuses the light beam onto the focal plane assembly (FPA) - the yellow circular plate with the goldish cable coming out of it. The FPA contains two state-of-the-art sensor chips to detect light. The FPA is provided by NASA's Goddard Space Flight Center.
NIRSpec is developed by ESA with EADS Astrium Germany GmbH as the prime contractor.