4. Raster-dot spectro-imagers

These spectro-imagers have a field of view extending in both directions: some can therefore take an instantaneous measurement of the spectro-image, while others require a scan, which is then carried out without modifying the field of view.

Instruments operating in this mode can be grouped into three families. The first is that of instruments which juxtapose images of the scene at the wavelengths of interest (paragraph 4.1 ). The second are those that use a dispersive element to spatially spread the spectra across the detection plane (paragraphs