The science case for METIS dictates the following key requirements for the instrument design:
- Diffraction-limited imaging in L, M and N bands with a field of view of approximately 18 x 18".The imager also includes coronagraphy in L and N bands; a low resolution slit spectrograph (R < 5000); and N-band polarimetry
- An IFU-fed high-resolution spectrograph in L and M bands with a field of view of 0.4 x 1.5" and spectral resolving power of ~100,000.
The instrument consists of two separate units, one for the imager and another for the spectrograph, and is entirely encased in a cryostat to maintain the stable low temperatures required for good performance at mid-infrared wavelengths. To achieve diffraction limited performance, METIS will use adaptive optics correction to compensate for atmospheric turbulence. The instrument will be able to observe with both natural and laser guide stars.
See the image gallery for views of the instrument.