# US 2019/0170576 A1 · Fourier transform multi-channel spectral imager > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2019/0170576 A1 - Document ID: US20190170576A1 - Status: Published application - Kind: A1 - Application number: 16/313,721 - Filed: 2017-06-30 - Published: 2019-06-06 - Earliest claimed: 2016-06-30 - Assignees: Office National d'Etudes et de Recherches Aerospatiales; Universite Grenoble Alpes - Applicants: Office National D'Etudes Et De Recherches Aerospatiales; Universite Grenoble Alpes - Inventors: Nicolas GUERINEAU; Etienne LE COARER; Yann FERREC; Florence DE LA BARRIERE - Web page: https://patentgrep.com/patent/US20190170576A1 ## CPC - G01J 3/0208: {using focussing or collimating elements, e.g. lenses or mirrors; performing aberration correction} - G01J 3/0205: {Optical elements not provided otherwise, e.g. optical manifolds, diffusers, windows} - G01J 3/0256: {Compact construction} - G01J 3/0297: {Constructional arrangements for removing other types of optical noise or for performing calibration} - G01J 3/26: using multiple reflection, e.g. Fabry-Perot interferometer, variable interference filters - G01J 3/2803: {using photoelectric array detector} - G01J 3/2823: {Imaging spectrometer} - G01J 3/4531: {Devices without moving parts} - G01J: MEASUREMENT OF INTENSITY, VELOCITY, SPECTRAL CONTENT, POLARISATION, PHASE OR PULSE CHARACTERISTICS OF INFRARED, VISIBLE OR ULTRAVIOLET LIGHT; COLORIMETRY; RADIATION PYROMETRY (light sources F21, H01J, H01K, H05B; investigating properties of materials by optical means G01N) ## Abstract A spectral imager, including: a photodetector including a plurality of photosensitive sites exposed on a photosensitive surface; a collimating lens including an intermediate focal plane; an array of interferometers including two main waves, each including a cavity defined by two faces; an array of microlenses arranged in a plane parallel to the photosensitive surface, each microlens paired with an interferometer to form an optical pair, including an image focal plane coinciding with the photosensitive surface and facing a section of the photosensitive surface. ## Claims ### Claim at position 1 1-15. (canceled) ### Claim 16 A fourier transform multichannel spectral imager, comprising: a photodetector comprising a plurality of photosensitive sites flush with a photosensitive surface of the photodetector; a network of two majority wave interferometers, each comprising a cavity delimited by two faces facing each other and parallel to the photosensitive surface, the two faces of each interferometer being at a different spacing from one interferometer to the next, the interferometers of the interferometers network being arranged in a plane parallel to the photosensitive surface; a network of microlenses formed in a plane parallel to the photosensitive surface; each microlens in the network of microlenses being paired with an interferometer in the network of two majority wave interferometers to form an optical pair, the optical pair comprising a focal image plane coincident with the photosensitive surface, the pair facing a section of the photosensitive surface. ### Claim 17 (depends on 16) A spectral imager according to claim 16, further comprising a signal separation network, each signal separator being paired with an optical pair and configured such that an image formed by each optical pair at the photosensitive surface is limited to a section of the photosensitive surface facing which the optical pair is positioned. ### Claim 18 (depends on 17) A spectral imager according to claim 17, wherein each signal separator comprises first side walls perpendicular to the photosensitive surface, and in contact with the photosensitive surface. ### Claim 19 (depends on 17) A spectral imager according to claim 17, wherein each signal separator comprises second side walls, each of the second side walls optically isolating two adjacent two majority wave interferometers. ### Claim 20 (depends on 16) A spectral imager according to claim 16, comprising a first sub-slide, the first sub-slide comprises a first face and a second face parallel to the first face, the second face being parallel to and facing a first face of a second sub-slide, the second sub-slide comprising a second face on which the network of microlenses is located; and further comprising steps formed on one of the two faces chosen from among the second face of the first sub-slide and the first face of the second sub-slide, the other of the two faces being a plane diopter, the steps formed on one of the two faces form the network of two majority wave interferometers with the plane diopter, each step being formed at a different depth from other steps, and being vertically in line with a microlens along a direction perpendicular to the photosensitive surface. ### Claim 21 (depends on 20) A spectral imager according to claim 20, wherein the second face of the first sub-slide has a reflection factor equal to between 5% and 90%. ### Claim 22 (depends on 20) A spectral imager according to claim 20, wherein the first face of the second sub-slide has a reflection factor equal to between 5% and 90%. ### Claim 23 (depends on 19) A spectral imager according to claim 19, wherein shape of the steps is square or rectangular or hexagonal. ### Claim 24 (depends on 16) A spectral imager according to claim 16, wherein the interferometers in the network of two majority wave interferometers are distributed in a two-dimensional matrix, on a square two-dimensional square matrix. ### Claim 25 (depends on 16) A spectral imager according to claim 16, wherein the photodetector, the network of two majority wave interferometers, and the microlenses network are all located in a cryostatic chamber, and the cryostatic chamber comprises an aperture. ### Claim 26 (depends on 16) A spectral imager according to claim 16, wherein each of the microlenses has a curved surface, the curved surfaces including an anti-reflection deposit, the anti-reflection treatment being a layer of dielectric material. ### Claim 27 (depends on 16) A spectral imager according to claim 16, wherein the interferometers in the network of two majority wave interferometers have an average coefficient of reflection equal to between 12% and 60%. ### Claim 28 (depends on 16) Use of the spectral imager according to claim 16 for detection and/or quantification of gas and/or aerosols. ### Claim 29 (depends on 28) Use according to claim 28, wherein the gases are greenhouse gases; carbon dioxide; water; or methane. ### Claim 30 (depends on 16) A mobile electronic device comprising a spectral imager according to claim 16, the mobile electronic device being a smartphone or a tablet or a drone.