Abstract: The invention relates to a multispectral imaging device comprising a multiple-quantum-well structure operating on inter-sub-band transitions by absorbing radiation at a wavelength ? lying within a set of wavelengths to which said structure is sensitive, said structure comprising a matrix of individual detection pixels, characterized in that the matrix is organized in subsets (Eij) of four individual detection pixels, a first individual detection pixel (P?1) comprising a first diffraction grating (R?1) sensitive to a first subset of wavelengths, a second individual detection pixel (P?2) comprising a second diffraction grating (R?2) sensitive to a second subset of wavelengths, a third individual detection pixel (P?3) comprising a third diffraction grating (R?3) sensitive to a third subset of wavelengths and a fourth individual detection pixel (P??) not comprising a wavelength-selective diffraction grating, the first, second and third subsets of wavelengths belonging to the set of wavelengths to which said struc

Abstract: The invention relates to a detector comprising a multiple quantum well structure operating on interband or intersubband transitions by absorption of radiation having a wavelength ? having a polarization comprising a component perpendicular to the plane of the multiple quantum well structure, and comprising optical coupling means for coupling said radiation, wherein the coupling means comprise a set of first diffractive lamellar features that are distributed along at least a first direction and a set of second diffractive lamellar features that are distributed along at least a second direction, said first and second directions being mutually perpendicular and lying in a plane parallel to the plane of the multiple quantum well structure.

Abstract: The invention relates to a multispectral imaging device comprising a multiple-quantum-well structure operating on inter-sub-band transitions by absorbing radiation at a wavelength ? lying within a set of wavelengths to which said structure is sensitive, said structure comprising a matrix of individual detection pixels, characterized in that the matrix is organized in subsets (Eij) of four individual detection pixels, a first individual detection pixel (P?1) comprising a first diffraction grating (R?1) sensitive to a first subset of wavelengths, a second individual detection pixel (P?2) comprising a second diffraction grating (R?2) sensitive to a second subset of wavelengths, a third individual detection pixel (P?3) comprising a third diffraction grating (R?3) sensitive to a third subset of wavelengths and a fourth individual detection pixel (P??) not comprising a wavelength-selective diffraction grating, the first, second and third subsets of wavelengths belonging to the set of wavelengths to which said struc

Abstract: The invention relates to a polarimetric imaging device comprising a multiple-quantum-well structure operating on inter-sub-band transitions by absorbing radiation at a wavelength ?, said structure comprising a matrix of individual detection pixels, characterized in that the matrix is organized in subsets of four individual pixels, a first pixel comprising a first diffraction grating (RP1) sensitive to a first polarization, a second polarimetric pixel comprising a second diffraction grating (RP2) sensitive to a second polarization orthogonal to the first polarization, a third polarimetric pixel comprising a third diffraction grating (RP3) sensitive to a third polarization oriented at an angle between the first and second polarizations and a fourth pixel not comprising a polarization-selective diffraction rating (R2D).

Abstract: The invention relates to an optical coupling structure intended to couple electromagnetic radiation to the surface of a photodetector, wherein a coupling surface paved along mutually perpendicular first and second directions by a set of N series (M1i, M2i, . . . . Mni) of first features, second features, . . . nth features, the features being identical within any one series, the features being distributed along the first and second directions, the distance between the centers of two adjacent features or the inter-reticular distances between two adjacent features being variable. The subject of the invention is also a detector or a laser source comprising said coupling structure.

Abstract: The invention relates to a detector comprising a multiple quantum well structure operating on interband or intersubband transitions by absorption of radiation having a wavelength ? having a polarization comprising a component perpendicular to the plane of the multiple quantum well structure, and comprising optical coupling means for coupling said radiation, wherein the coupling means comprise a set of first diffractive lamellar features that are distributed along at least a first direction and a set of second diffractive lamellar features that are distributed along at least a second direction, said first and second directions being mutually perpendicular and lying in a plane parallel to the plane of the multiple quantum well structure.

Abstract: The invention relates to an optical coupling structure intended to couple electromagnetic radiation to the surface of a photodetector, wherein a coupling surface paved along mutually perpendicular first and second directions by a set of N series (M1i, M2i, . . . Mni) of first features, second features, . . . nth features, the features being identical within any one series, the features being distributed along the first and second directions, the distance between the centers of two adjacent features or the inter-reticular distances between two adjacent features being variable. The subject of the invention is also a detector or a laser source comprising said coupling structure.

Abstract: This optical polarimetric detector comprises: a first active detector element having a photoconductor (1) with which a first diffraction grating (3) is associated allowing incident light from a first specific polarization direction to be coupled in the first detector element and allowing the latter to detect the light having this first polarization direction; a second active detector element having a photoconductor (1′) with which a second diffraction grating (3′) is associated allowing incident light from a second polarization direction to be coupled in the second detector element and allowing the latter to detect the light having this second polarization direction. Furthermore, a detector (2) is provided making it possible to eliminate the background noise detected by previous detectors.

Abstract: A bi-functional optical detector including a first active photoconduction detection element configured to detect light within first and second wavelength ranges, a first diffraction grating associated with the first detection element and configured to couple the light within the first wavelength range so that the first active photoconducting detection element detects the light in the first wavelength range, a second active photoconduction detection element configured to detect light within the first and second wavelength ranges, and a second diffraction grating associated with the second detection element and configured to couple the light within the second wavelength range so that the second active photoconduction detection element detects the light in the second wavelength range.

Abstract: This optical polarimetric detector comprises:

Abstract: The basic idea is as follows: operational simulations of subtractive focal planes, based on the French patent No. 2 756 666, have shown that the optimal subtraction rate should not be total in order to preserve the dynamic range of the system. In this case, the low-frequency fluctuations of the temperature of the focal plane of the bias voltages will be amplified and will give rise to a fluctuation of the mean gray level of the signal at output of the multiplexer. This variation can be corrected simply by: the making of several columns of subtractive pixels without diffraction grating, for which the integrated signal is directly the residual level of the thermal current; the integration of a comparator circuit at input of the electronic card to subtract the signal generated in the reference pixels from the signals integrated into the active pixels.

Abstract: The basic idea is as follows: operational simulations of subtractive focal planes, based on the French patent No. 2 756 666, have shown that the optimal subtraction rate should not be total in order to preserve the dynamic range of the system. In this case, the low-frequency fluctuations of the temperature of the focal plane of the bias voltages will be amplified and will give rise to a fluctuation of the mean gray level of the signal at output of the multiplexer.

Abstract: This bi-functional optical detector comprises:

Abstract: The disclosure relates to a bispectral electromagnetic wave detector including at least one first and one second overlaid plane active detector elements separated by a common layer, said first and second detector elements being sensitive to the different wavelengths; a first means of connection connected in common to said first and second detector elements, a second means of connection connected to said first detector element, and a third means of connection connected to said second detector element; means for applying successively a control voltage to each means of connection; and means connected to said first means of connection to detect a photoconduction current each time a control voltage is applied. The invention is used in applications requiring detection of electromagnetic waves in two bands of different wavelengths.

Abstract: An electromagnetic wave detector having a first detector element including an active photoconducting material capable of detecting a band of wavelength and a second detector element including an active photoconducting material capable of detecting the same band of wavelength. A common layer is positioned between the first and second detector elements. A first and second connectors are configured to connect to the first and second detector elements, respectively. A third connector is configured to connect in common to the first and second detector elements. The detector further includes contact mechanisms configured to apply control voltages where the voltage applied to the third connector has a value between the values applied to the first and second connectors. A reading circuit connected to the third connector reads a photoconduction current difference between the first and the second detector elements.