Method and device for correcting spatial response for imaging fourier transform spectrometers

A method for correcting spatial response for an imaging Fourier transform spectrometer having at least one mode of operation called interferometric mode consisting in acquiring interferograms, the interferometric mode having a first spatial resolution corresponding to the dimension of one macropixel, one macropixel being made up of several pixels of an array of a detector placed in an image plane, and a mode of operation called image mode consisting in acquiring images, the image mode having a second spatial resolution corresponding to the dimension of one superpixel, one superpixel being made up of at least one pixel of the array of the detector, said method comprising at least the following steps:

• a prior step of calculation of equalization parameters (âi, {circumflex over (b)}i), for all the superpixels i comprising a gain and an offset, from data acquired on calibration scenes,
• a step of determination of equalization coefficients at a so-called pseudo superpixel level determining the gains and offsets at macropixel level ({circumflex over (α)}k, {circumflex over (β)}k), from an image acquired in image mode, and gains and offsets determined in the prior step,
• a step of equalization at pseudo superpixel level, applying the equalization coefficients ({circumflex over (α)}k, {circumflex over (β)}k) to a macropixel (k) from an acquisition (Ik) in the interferogram mode of the imaging spectrometer in order to restore an equalized interferogram (Ieq—k).