Proceedings Article | 26 October 2007
Proc. SPIE. 6744, Sensors, Systems, and Next-Generation Satellites XI
KEYWORDS: Optical components, Optical design, Beam splitters, Sensors, Calibration, Spectroscopy, Coating, Infrared spectroscopy, Infrared radiation, Mars
The Mars Infrared MApper (MIMA) is a FT-IR miniaturised spectrometer which is being developed for ESA ExoMars
Pasteur mission. MIMA will be mounted on the rover mast and so it must be compact and light-weight. The scientific
goals and its thermo-mechanical design are presented in two companion papers [1] and [2]. In this work the optical
design will be reviewed and the results of the tests performed on some optical components will be presented. The design
has faced challenging constraints mainly linked to the requirement of keeping the performances good enough to fulfil the
scientific objectives of the mission, while, at the same time, it was imperative to keep the overall size and weigh within
the allocated resources. In addition the instrument must be able to operate in the very harsh environment of the Martian
surface and to withstand, without permanent damage, even harsher conditions as well as the severe dynamic loads
expected at landing on Mars. The chosen solution is a single channel double pendulum interferometer, covering the
spectral range between 2 and 25 micron, crucial for the scientific interpretation of the recorded spectra, with a resolution
variable between 10 and 5 cm-1. Since the spectral range is too wide to be covered by a single detector, it has been
decided to use two different detectors, mounted side by side, in a customised case. Such innovative solution has
obviously pros and cons and the optical design has been driven by the need to reduce the inconveniences, while
maintaining the advantages.
