Optomechanical Design of a Compact Imaging Spectrometer for a Microsatellite STSAT3

Abstract

A compact imaging spectrometer (COMIS) is currently under development for use in the STSAT3 microsatellite. COMS images the Earth's surface and atmosphere with ground sampling distances of similar to 30 in in the 1.8 similar to 62 spectral bands (4.0 similar to 1.05 mu m) for the nadir looking at an altitude of 700 kin. CONES has an imaging telescope and an imaging spectrometer box into which three electronics PCBs are embedded. These are designed into a single assembly with dimensions of 35(L) X 20(W) x 12(H) cm(3) and a, mass of 4.3 kg. Optomechanical design efforts are focused on manufacturing ease, alignment, assembly, testing and improved robustness, in space environments. Finite element analysis demonstrates that COMIS will survive in launch and space environments and perform the system modulation transfer function (MTF) in excess of 0.29 at the Nyquist frequency of the CCD detector (38.5 lines-per-mm).