The MetOp-SG programme is a joint Programme of EUMETSAT and ESA. ESA develops the prototype MetOp-SG
satellites (including associated instruments) and procures, on behalf of EUMETSAT, the recurrent satellites (and
associated instruments). Two parallel, competitive phase A/B1 studies for MetOp Second Generation (MetOp-SG) have
been concluded in May 2013. The implementation phases (B2/C/D/E) are planned to start the first quarter of 2014.
ESA is responsible for instrument design of six missions, namely Microwave Sounding Mission (MWS), Scatterometer
mission (SCA), Radio Occultation mission (RO), Microwave Imaging mission (MWI), Ice Cloud Imager (ICI) and
Multi-viewing, Multi-channel, Multi-polarisation imaging mission (3MI).
The paper will present the main performances of the 3MI instrument and will highlight the performance improvements
with respect to its heritage derived by the POLDER instrument, such as number of spectral channels and spectral range
coverage, swath and ground spatial resolution. The engineering of some key performance requirements (multi-viewing,
polarisation sensitivity, straylight etc.) will also be discussed. The results of the feasibility studies will be presented
together with the programmatics for the instrument development.
Several pre-development activities have been initiated to retire highest risks and to demonstrate the ultimate
performances of the 3MI optics. The scope, objectives and current status of those activities will be presented. Key
technologies involved in the 3MI instrument design and implementation are considered to be: the optical design featuring
aspheric optics, the implementation of broadband Anti Reflection coatings featuring low polarisation and low de-phasing
properties, the development and qualification of polarisers with acceptable performances as well as spectral filters with
good uniformities over a large clear aperture.