This instrument will provide full images of the Earth every 10 minutes in 16 spectral channels between 0.44 and 13.3 μm. The ground resolution is ranging from 0.5 km to 2 km. The FCI is composed of a telescope developed by Kayser-Threde, which includes a Scan mirror for the full Earth coverage, and a calibration mechanism with an embedded black body dedicated to accurate in-flight IR radiometric calibration. The image produced by the telescope is split into several spectral groups by a spectral separation assembly (SSA) thanks to dichroïc beamsplitters. The output beams are collimated to ease the instrument integration before reaching the cryostat. Inside, the cold optics (CO-I) focalize the optical beams onto the IR detectors. The cold optics and IR detectors are accurately positioned inside a common cold plate to improve registration between spectral channels. Spectral filters are integrated on top of the detectors in order to achieve the required spectral selection. This article describes the FCI optical design and performances. We will focus on the image quality needs, the high line-of-sight stability required, the spectral transmittance performance, and the stray-light rejection. The FCI currently under development will exhibit a significant improvement of performances with respect to MSG. |
CITATIONS
Cited by 1 scholarly publication.
Mirrors
Space telescopes
Telescopes
Sensors
Near infrared
Sun
Calibration