New miniaturised spectrometer developed

Spatial heterodyne interferometers are an enabling technology to build highly miniaturised optical instruments to observe faint emissions in the atmosphere. These static Fourier-Transform spectrometers can reach high resolutions over a narrow spectral band in a compact, yet robust and light sensitive design – making them well suited to the space environment.

The small size means they are well-matched to use on small  and nano satellites for remote sensing of trace gases in the atmosphere.

A recently closed TDE activity  with OHB in Germany built a thoroughly verified instrument suitable for measuring the oxygen atmospheric emission.  The activity matured the Spatial Heterodyne Spectrometer design, manufacturing, alignment and verification processes to enable future small series production of these types of instrument, with fast development cycles.

The activity successfully concluded with the development flight model breadboard of the satellite instrument, with characteristics necessary to measure the Oxygen A-band emission. The instrument is capable of measuring temperatures in the middle atmosphere for gravity wave characterisation.

The spectrometer’s design specifications are based on mission parameters that can be analysed with an extensive tool suite tailored for optical systems. Close interaction between both the design and manufacturing disciplines meant that the design is optimised to align manufacturing and assembly. The activity utilised the ultra-high precision manufacturing capabilities at MEOPTA in the Czech Republic, to facilitate a controlled and reproducible alignment of the instrument, making batch production feasible. The spectrometer could then be characterised at OHB using state of the art, highly precise, metrology setups for spectral, radiometric and geometric calibration, to correct instrument artefacts.

The activity also improved European industry knowhow to develop, build and characterise these instruments for a variety of future applications. The next steps target the development of a flight model, increasing the TRL of all the subsystems and, specifically, improving an oxygen A-band remote sensing instrument for use on an ESA  small satellite platform.

T116-506MM closed at the end of 2020. All documentation is available on the TEC-DMS.