Multispectral imaging device incorporating a quantic multi-well structure that incorporates a matrix of elementary detection pixels operating on inter-sub-band transitions, by absorption of radiation at a wavelength λ lying within a set of wavelengths to which said structure is sensitive, with the elementary detection pixel matrix being designed to be illuminated by the said radiation, with each elementary detection pixel incorporating a separate said structure incorporating a matrix of individual detection pixels incorporating a separate stud (CSMPQ) composed of a stack of semiconducting layers produced on the surface of a substrate and constituting the quantic multi-well structure, with the matrix being organized into subsets of four elementary detection pixels (Eij), with each of the said subsets incorporating: - a first elementary detection pixel (Pλ1) incorporating a first diffraction grating (Rλ1) positioned on the surface of the stud of the first pixel, with the first grating being sensitive to a unique first subset of wavelengths centered on a first wavelength (λ1); - a second elementary detection pixel (Pλ2) incorporating a second diffraction grating (Rλ2) positioned on the surface of the stud of the second pixel, with the second grating being sensitive to a unique second subset of wavelengths centered on a second wavelength (λ2); - a third elementary detection pixel (Pλ3) positioned on the surface of the stud of the third pixel, with the third grating being sensitive to a unique third subset of wavelengths centered on a third wavelength (λ3); with the first, second and third wavelengths being different wavelengths; characterized in that each of the said subsets incorporates: - a fourth individual detection pixel (PΔλ) not incorporating a wavelength-selective diffraction grating positioned on the stud of the fourth pixel; characterized in that the first, second and third subsets of wavelengths belong to the set of wavelengths to which the said structure is sensitive; and in that the device incorporates a system for processing signals recovered at the elementary detection pixels, with the signal processing system incorporating a system of summing signals from, respectively, the first, second and third elementary detection pixels and a system for subtraction of the signal emitted by the fourth elementary detection pixel. - a first elementary detection pixel (Pλ1) incorporating a first diffraction grating (Rλ1) positioned on the surface of the stud of the first pixel, with the first grating being sensitive to a unique first subset of wavelengths centered on a first wavelength (λ1); - a second elementary detection pixel (Pλ2) incorporating a second diffraction grating (Rλ2) positioned on the surface of the stud of the second pixel, with the second grating being sensitive to a unique second subset of wavelengths centered on a second wavelength (λ2); - a third elementary detection pixel (Pλ3) positioned on the surface of the stud of the third pixel, with the third grating being sensitive to a unique third subset of wavelengths centered on a third wavelength (λ3); - a fourth individual detection pixel (PΔλ) not incorporating a wavelength-selective diffraction grating positioned on the stud of the fourth pixel;