The HARMONI/ELT spectrographs

HARMONI is an Integral Field Spectrograph (IFS) for ESO’s ELT. It has been selected as the first light spec- trograph and will provide the workhorse spectroscopic capabilities for the ELT for many years. HARMONI is currently at the PDR-level and the current design for the HARMONI IFS consists of a number of spaxel scales sampling down to the diffraction limit of the telescope. It uses a field splitter and image slicer to divide the field into 4 sub-units, each providing an input slit to one of four nearly identical spectrographs. All spectrographs will operate at near infrared wavelengths (0.81-2.45 micrometers), sampling different parts of the spectrum with a range of spectral resolving powers (3300, 7000, 18000). In addition, two of the four spectrographs will have a Visible capability (0.5-0.83 micrometers) operating with seeing-limited observations. This proceeding presents an overview of the opto-mechanical design and specifications of the spectrograph units for HARMONI.