Classifications

• • G—PHYSICS
  • G01—MEASURING; TESTING
  • G01J—MEASUREMENT OF INTENSITY, VELOCITY, SPECTRAL CONTENT, POLARISATION, PHASE OR PULSE CHARACTERISTICS OF INFRARED, VISIBLE OR ULTRAVIOLET LIGHT; COLORIMETRY; RADIATION PYROMETRY
  • G01J1/00—Photometry, e.g. photographic exposure meter
  • G01J1/02—Details
  • G01J1/04—Optical or mechanical part supplementary adjustable parts
  • G01J1/0407—Optical elements not provided otherwise, e.g. manifolds, windows, holograms, gratings
  • G01J1/0411—Optical elements not provided otherwise, e.g. manifolds, windows, holograms, gratings using focussing or collimating elements, i.e. lenses or mirrors; Aberration correction
• • G—PHYSICS
  • G01—MEASURING; TESTING
  • G01J—MEASUREMENT OF INTENSITY, VELOCITY, SPECTRAL CONTENT, POLARISATION, PHASE OR PULSE CHARACTERISTICS OF INFRARED, VISIBLE OR ULTRAVIOLET LIGHT; COLORIMETRY; RADIATION PYROMETRY
  • G01J1/00—Photometry, e.g. photographic exposure meter
  • G01J1/02—Details
  • G01J1/04—Optical or mechanical part supplementary adjustable parts
  • G01J1/0407—Optical elements not provided otherwise, e.g. manifolds, windows, holograms, gratings
  • G01J1/0437—Optical elements not provided otherwise, e.g. manifolds, windows, holograms, gratings using masks, aperture plates, spatial light modulators, spatial filters, e.g. reflective filters
• • G—PHYSICS
  • G01—MEASURING; TESTING
  • G01J—MEASUREMENT OF INTENSITY, VELOCITY, SPECTRAL CONTENT, POLARISATION, PHASE OR PULSE CHARACTERISTICS OF INFRARED, VISIBLE OR ULTRAVIOLET LIGHT; COLORIMETRY; RADIATION PYROMETRY
  • G01J1/00—Photometry, e.g. photographic exposure meter
  • G01J1/02—Details
  • G01J1/04—Optical or mechanical part supplementary adjustable parts
  • G01J1/0488—Optical or mechanical part supplementary adjustable parts with spectral filtering
• • G—PHYSICS
  • G01—MEASURING; TESTING
  • G01J—MEASUREMENT OF INTENSITY, VELOCITY, SPECTRAL CONTENT, POLARISATION, PHASE OR PULSE CHARACTERISTICS OF INFRARED, VISIBLE OR ULTRAVIOLET LIGHT; COLORIMETRY; RADIATION PYROMETRY
  • G01J1/00—Photometry, e.g. photographic exposure meter
  • G01J1/02—Details
  • G01J1/04—Optical or mechanical part supplementary adjustable parts
  • G01J1/06—Restricting the angle of incident light
• • G—PHYSICS
  • G01—MEASURING; TESTING
  • G01J—MEASUREMENT OF INTENSITY, VELOCITY, SPECTRAL CONTENT, POLARISATION, PHASE OR PULSE CHARACTERISTICS OF INFRARED, VISIBLE OR ULTRAVIOLET LIGHT; COLORIMETRY; RADIATION PYROMETRY
  • G01J1/00—Photometry, e.g. photographic exposure meter
  • G01J1/42—Photometry, e.g. photographic exposure meter using electric radiation detectors
  • G01J1/4228—Photometry, e.g. photographic exposure meter using electric radiation detectors arrangements with two or more detectors, e.g. for sensitivity compensation
• • G—PHYSICS
  • G02—OPTICS
  • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
  • G02B3/00—Simple or compound lenses
  • G02B3/0006—Arrays
  • G02B3/0037—Arrays characterized by the distribution or form of lenses
  • G02B3/0062—Stacked lens arrays, i.e. refractive surfaces arranged in at least two planes, without structurally separate optical elements in-between
  • G02B3/0068—Stacked lens arrays, i.e. refractive surfaces arranged in at least two planes, without structurally separate optical elements in-between arranged in a single integral body or plate, e.g. laminates or hybrid structures with other optical elements
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
  • H01L27/00—Devices consisting of a plurality of semiconductor or other solid-state components formed in or on a common substrate
  • H01L27/14—Devices consisting of a plurality of semiconductor or other solid-state components formed in or on a common substrate including semiconductor components sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation and specially adapted either for the conversion of the energy of such radiation into electrical energy or for the control of electrical energy by such radiation
  • H01L27/144—Devices controlled by radiation
  • H01L27/146—Imager structures
  • H01L27/14601—Structural or functional details thereof
  • H01L27/1462—Coatings
  • H01L27/14623—Optical shielding
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
  • H01L27/00—Devices consisting of a plurality of semiconductor or other solid-state components formed in or on a common substrate
  • H01L27/14—Devices consisting of a plurality of semiconductor or other solid-state components formed in or on a common substrate including semiconductor components sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation and specially adapted either for the conversion of the energy of such radiation into electrical energy or for the control of electrical energy by such radiation
  • H01L27/144—Devices controlled by radiation
  • H01L27/146—Imager structures
  • H01L27/14601—Structural or functional details thereof
  • H01L27/14625—Optical elements or arrangements associated with the device
  • H01L27/14627—Microlenses
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
  • H01L27/00—Devices consisting of a plurality of semiconductor or other solid-state components formed in or on a common substrate
  • H01L27/14—Devices consisting of a plurality of semiconductor or other solid-state components formed in or on a common substrate including semiconductor components sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation and specially adapted either for the conversion of the energy of such radiation into electrical energy or for the control of electrical energy by such radiation
  • H01L27/144—Devices controlled by radiation
  • H01L27/146—Imager structures
  • H01L27/14601—Structural or functional details thereof
  • H01L27/14625—Optical elements or arrangements associated with the device
  • H01L27/14629—Reflectors
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
  • H01L27/00—Devices consisting of a plurality of semiconductor or other solid-state components formed in or on a common substrate
  • H01L27/14—Devices consisting of a plurality of semiconductor or other solid-state components formed in or on a common substrate including semiconductor components sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation and specially adapted either for the conversion of the energy of such radiation into electrical energy or for the control of electrical energy by such radiation
  • H01L27/144—Devices controlled by radiation
  • H01L27/146—Imager structures
  • H01L27/14643—Photodiode arrays; MOS imagers
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
  • H01L27/00—Devices consisting of a plurality of semiconductor or other solid-state components formed in or on a common substrate
  • H01L27/14—Devices consisting of a plurality of semiconductor or other solid-state components formed in or on a common substrate including semiconductor components sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation and specially adapted either for the conversion of the energy of such radiation into electrical energy or for the control of electrical energy by such radiation
  • H01L27/144—Devices controlled by radiation
  • H01L27/146—Imager structures
  • H01L27/14678—Contact-type imagers

Definitions

• the present description relates generally to an image acquisition device.
• An image acquisition device generally comprises an image sensor and an optical system.
• the optical system can be an angular filter, or a set of lenses, interposed between the sensitive part of the sensor and the object to be imaged.
• the image sensor generally comprises an array of photodetectors capable of generating a signal proportional to the intensity of light received.
• An angular filter is a device making it possible to filter incident radiation as a function of the incidence of this radiation and thus block the rays whose incidence is greater than a desired angle, called maximum incidence, which makes it possible to forming a clear image of the object to be imaged on the sensitive part of the image sensor.
• One embodiment overcomes all or part of the drawbacks of known image acquisition devices.
• One embodiment provides for a device comprising a stack comprising, in order, at least: an image sensor in MOS technology suitable for detecting radiation; a first array of lenses; a structure composed at least of a first matrix of openings delimited by walls opaque to said radiation; and a second lens array.
• the number of lenses of the second array is greater than the number of lenses of the first array.
• the number of lenses of the second array is two to ten times greater than the number of lenses of the first array, preferably twice as much.
• the device comprises an adhesive layer between said structure and the first array of lenses.
• the device comprises a refractive index matching layer between said structure and the first array of lenses.
• each opening of the first matrix is associated with a single lens of the second array; and the optical axis of each lens of the second array is aligned with the center of an opening of the first array.
• the structure comprises, under the first array of openings, a second array of openings, delimited by walls opaque to said radiation.
• the number of openings of the first die is identical to the number of openings of the second die.
• the center of each opening in the first die is aligned with the center of an opening in the second die.
• the lenses of the second array and the lenses of the first array are plan-convex.
• the plane faces of the lenses of the first array and of the second array are on the sensor side.
• the openings are filled with a material at least partially transparent to said radiation.
• the lenses of the first network have a diameter greater than the diameter of the lenses of the second network.
• the structure comprises a third array of plano-convex lenses, the plane faces of the lenses of the second array of lenses and of the third array of lenses facing each other.
• the third lens array is located between the first array of apertures and the first array of lenses or between the first array of apertures and the second array of lenses.
• the optical axis of each lens of the second array is aligned with the optical axis of a lens of the third array.
• the image focal planes of the lenses of the second array are merged with the object focal planes of the lenses of the third array.
• the number of lenses of the third network is greater than the number of lenses of the second network. According to one embodiment, the lenses of the second network have a diameter greater than that of the lenses of the third network.
• FIG. 1 is a partial and schematic block diagram of an example of an image acquisition system
• FIG. 2 represents, in a partial and schematic sectional view, an example of an image acquisition device
• FIG. 3 represents, in a partial and diagrammatic sectional view, an embodiment of the image acquisition device illustrated in FIG. 2;
• FIG. 4 represents, in a partial and schematic sectional view, another embodiment of the image acquisition device illustrated in FIG. 2;
• FIG. 5 represents, in a partial and diagrammatic sectional view, yet another embodiment of the image acquisition device illustrated in FIG. 2;
• FIG. 6 represents, in a partial and diagrammatic sectional view, yet another embodiment of the image acquisition device illustrated in FIG. 2;
• FIG. 7 represents, in a partial and diagrammatic sectional view, yet another embodiment of the image acquisition device illustrated in FIG. 2;
• FIG. 8 represents, in a partial and schematic sectional view, yet another embodiment of the image acquisition device illustrated in FIG. 2. Description of the embodiments
• a layer or a film is said to be opaque to a radiation when the transmittance of radiation through the layer or film is less than 10%.
• a layer or a film is said to be transparent to radiation when the transmittance of the radiation through the layer or the film is greater than 10%, preferably greater than 50%.
• all the elements of the optical system which are opaque to radiation have a transmittance which is less than half, preferably less than a fifth, more preferably less than a tenth, of the highest transmittance. lower of the elements of the optical system transparent to said radiation.
• the electromagnetic radiation passing through the optical system in operation is called “useful radiation”.
• optical element of micrometric size is called an optical element formed on one face of a support, the maximum dimension of which, measured parallel to said face, is greater than 1 ⁇ m and less than 1. mm.
• each optical element of micrometric size corresponds to a lens of micrometric size, or microlens, composed of two dioptres.
• these embodiments can also be implemented with other types of optical elements of micrometric size, each optical element of micrometric size being able to correspond, for example, to a Fresnel lens of micrometric size, to a lens with a gradient index of micrometric size or to a diffraction grating of micrometric size.
• visible light is called electromagnetic radiation whose wavelength is between 400 nm and 700 nm and infrared radiation is called electromagnetic radiation whose wavelength is between 700 nm and 1 mm.
• infrared radiation a distinction is made in particular between near infrared radiation, the wavelength of which is between 700 nm and 1.7 ⁇ m.
• the refractive index of a material corresponds to the refractive index of the material for the range of wavelengths of the radiation picked up by the image sensor. Unless otherwise indicated, the refractive index is considered to be substantially constant over the wavelength range of the useful radiation, for example equal to the average of the refractive index over the wavelength range of the radiation picked up by the image sensor.
• FIG. 1 is a partial and schematic block diagram of an example of an image acquisition system.
• the image acquisition system illustrated in Figure 1, comprises: an image acquisition device 1 (DEVICE); and a processing unit 13 (PU).
• DEVICE image acquisition device 1
• PU processing unit 13
• the processing unit 13 preferably comprises means for processing the signals supplied by the device 1, not shown in FIG. 1.
• the processing unit 13 comprises, for example, a microprocessor.
• FIG. 2 is a partial and schematic sectional view of an example of an image acquisition device 1.
• FIG. 2 represents the image acquisition device 1, and a source 25 emitting radiation 27.
• the image acquisition device 1, illustrated in Figure 2 comprises from bottom to top: an image sensor 17 (SENSOR) in complementary metal oxide semiconductor technology (CMOS, Complementary Metal Oxide Semiconductor) which can be coupled to inorganic (crystalline silicon) or organic photodetectors or photodiodes suitable for detecting radiation 27; a first lens array 19 (LENS1); a matrix structure 21 (LAYER (S)); a second lens array 23 (LENS2); and an object 24.
• CMOS complementary metal oxide semiconductor technology
• CMOS complementary metal oxide semiconductor technology
• CMOS Complementary Metal Oxide Semiconductor
• the structure 21 and the second lens array 23 preferably form an optical filter 2 or angular filter.
• the image sensor 17 and the first array of lenses 19 preferably form a CMOS imager 3.
• the radiation 27 is, for example, in the visible range and / or in the infrared range. It may be radiation of a single wavelength or radiation of several wavelengths (or range of wavelengths).
• the light source 25 is illustrated in Figure 2, above the object 24. It may however, as a variant, be located between the object 24 and the filter 2. In the case of an application to the determination of fingerprints, the object 24 corresponds to the finger of a user.
• FIG. 3 represents, in a partial and schematic sectional view, an embodiment of the image acquisition device illustrated in FIG. 2.
• FIG. 3 represents an image acquisition device 101 in which the matrix structure 21 is composed of a layer 211 comprising a first matrix of openings 41 delimiting walls 39 opaque to said radiation.
• the image acquisition device 101 illustrated in Figure 3, comprises from bottom to top:
• the CMOS imager 3 composed of: the image sensor 17 (not detailed in the figures) preferably consisting of a substrate, read circuits, conductive tracks and photodiodes, a first passivation layer 29 (insulating) on and in contact with the image sensor 17, of a second layer 31 playing the role of a color filter covering the full plate the first layer 29, and of the first plane-convex lens array 19, whose flat faces are on the sensor side 17, covered by a third passivation layer 33;
• the angular filter 2 consisting of: of the structure 21 comprising the layer 211 of openings 41 and whose walls 39 are on and in contact with the fifth layer 37, of a substrate 43 covering the structure 21, and of the second plane-convex lens array 23, of which the flat faces are on the sensor side, covered by a sixth layer 45.
• the first array of lenses 19 makes it possible, for example, to focus the rays incident to the lenses 19 on the photodetectors present in the image sensor 17.
• the lens array 19 within the imager 3 forms a matrix of pixels in which a pixel corresponds, for example, substantially to the square in which is inscribed the circle corresponding to the surface of a lens 19.
• Each pixel thus comprises a lens 19 substantially centered on the pixel.
• all the lenses 19 have substantially the same diameter.
• the diameter of the lenses 19 is preferably substantially the same as the length of the sides of the pixels.
• the pixels of the CMOS imager 3 are substantially square.
• the length of the sides of the pixels is preferably between 0.7 ⁇ m and 50 ⁇ m, and is more preferably of the order of 30 ⁇ m.
• the imager 3 is substantially square.
• the length of the sides of the imager 3 is preferably between 5 mm and 50 mm, and is more preferably of the order of 10 mm.
• Layer 31 is preferably made of a material absorbing wavelengths between approximately 400 nm and 600 nm (cyan), preferably between 470 nm and 600 nm (green).
• Layer 29 may be of an inorganic material, for example of silicon oxide (S1O2), of silicon nitride. (SiN), or in a combination of these two materials (for example a multilayer stack).
• SiO2 silicon oxide
• SiN silicon nitride.
• the insulating layer 29 can be made of fluoropolymer, in particular the fluoropolymer known under the trade name "Cytop” from the company Bellex, of polyvinylpyrrolidone (PVP), of polymethyl methacrylate (PMMA), of polystyrene (PS) , parylene, polyimide (PI), acrylonitrile butadiene styrene (ABS), poly (ethylene terephthalate) (polyethylene terephthalate - PET), poly (ethylene naphthalate) (Polyethylene naphthalate - PEN), polymers cyclic olefin (Cyclo Olefin Polymer - COP), polydimethylsiloxane (PDMS), a photolithography resin, epoxy resin, acrylate resin or a mixture of at least two of these compounds.
• PVP polyvinylpyrrolidone
• PMMA polymethyl methacrylate
• PS polystyrene
• ABS polyimi
• the layer 29 can be made of an inorganic dielectric, in particular of silicon nitride, of silicon oxide or of aluminum oxide (Al2O3).
• Layer 33 is preferably a passivation layer which follows the shape of the microlenses 19 and which makes it possible to isolate and planarize the surface of the imager 3.
• Layer 33 can be made of an inorganic material, for example. in silicon oxide (S1O2) or in silicon nitride (SiN), or in a combination of these two materials (for example a multilayer stack).
• the optical filter 2 by the association of the second lens array 23 and the layer 211, is adapted to filter the incident radiation as a function of its angle of incidence by relative to the optical axes of the lenses 23 of the second array.
• the angular filter 2 is adapted so that the photodetectors of the image sensor 17 receive only the rays whose respective incidences, with respect to the optical axes of the lenses 23, are less than a maximum angle of incidence of less than 45 °, preferably less than 20 °, more preferably less than 5 ° , even more preferably less than 3 °.
• the optical filter 2 is adapted to block the rays of the incident radiation, the respective incidences of which with respect to the optical axes of the lenses 23 of the filter 2 are greater than the maximum angle of incidence.
• each opening 41 of the layer 211 is associated with a single lens 23 of the second array and each lens 23 is associated with a single opening 41.
• the lenses 23 are preferably contiguous .
• the optical axes of the lenses 23 are preferably aligned with the centers of the openings 41.
• the diameter of the lenses 23 of the second array is preferably greater than the maximum section (measured perpendicular to the optical axes of the lenses 23) of the openings 41 .
• the walls 39 are, for example, opaque to radiation
• the walls 39 are preferably opaque for wavelengths between 400 nm and 600 nm (cyan and green), used for imaging (biometry and fingerprint imaging).
• the height of the walls 39 is called "h".
• the openings 41 are arranged in rows and in columns.
• the openings 41 can have substantially the same dimensions.
• the diameter of the openings 41 (measured at the base of the openings, that is to say at the interface with the substrate 43) is called "wl".
• the diameter of each lens 23 is preferably greater than the diameter w1 of the opening 41 with which the lens 23 is associated.
• the openings 41 are arranged regularly according to the rows and according to the columns. Called “p" the repetition interval of the openings 41, that is to say the distance in top view between the centers of two successive openings 41 of a row or of a column.
• the openings 41 are shown with a trapezoidal cross section.
• the openings 41 can be square, triangular, rectangular, in the shape of a funnel.
• the width (or diameter) of the openings 41, at the level of the upper face of the layer 211 is greater than the width (or diameter) of the openings 41, at the level of the lower face of the layer 211. .
• the openings 41 can be circular, oval or polygonal, for example triangular, square, rectangular or trapezoidal.
• the openings 41, viewed from above, are preferably circular.
• the resolution of the optical filter 2, in section (XZ or YZ plane), is preferably greater than the resolution of the image sensor 17, preferably two to ten times greater. In other words, there are, in section (XZ or YZ plane), two to ten times more openings 41 than lenses 19 of the first array. Thus, a lens 19 is associated with at least four openings 41 (two openings in the YZ plane and two openings in the XZ plane).
• An advantage is that the difference between the resolution of the imager 3 and that of the angular filter 2 makes it possible to decrease the constraints in alignment of the filter 2 on the imager 3.
• the lenses 23 have substantially the same diameter.
• the diameter of the lenses 19 of the first array is thus greater than the diameter of the lenses 23 of the second array.
• the width wl is, in practice and preferably, less than the diameter of the lenses 23 so that the layer 39 has sufficient grip on the substrate 43.
• the width wl is preferably between 0.5 ⁇ m and 25 ⁇ m , for example equal to about 10 ⁇ m.
• the pitch p can be between 1 ⁇ m and 25 ⁇ m, preferably between 12 ⁇ m and 20 ⁇ m.
• the height h is, for example, between 1 ⁇ m and 1 mm, preferably, between 12 ⁇ m and 15 ⁇ m.
• the microlenses 23 and the substrate 43 are preferably made of transparent or partially transparent materials, that is to say transparent in a part of the spectrum considered for the target area, by example, imaging, over the range of wavelengths corresponding to the wavelengths used during exposure.
• the substrate 43 can be made of a transparent polymer which does not absorb at least the wavelengths considered, here in the visible and infrared range.
• This polymer can in particular be poly (ethylene terephthalate) PET, poly (methyl methacrylate) PMMA, cyclic olefin polymer (COP), polyimide (PI) or polycarbonate (PC).
• the substrate 43 is preferably made of PET.
• the thickness of the substrate 43 can, for example, vary from 1 to 100 ⁇ m, preferably between 10 and 50 ⁇ m.
• the substrate 43 can correspond to a color filter, to a polarizer, to a half-wave plate or to a quarter-wave plate.
• the microlenses 23 and 19 are made of materials whose refractive index is between 1.4 and 1.7, and is preferably of the order of 1.6 .
• the microlenses 23 and 19 can be made of silica, PMMA, a positive photosensitive resin, PET, poly (ethylene naphthalate) (PEN), COP, polydimethylsiloxane (PDMS) / silicone, epoxy resin or in acrylate resin.
• the microlenses 23 and 19 can be formed by creeping blocks of a photosensitive resin.
• the microlenses 19 and 23 can furthermore be formed by molding on a layer of PET, PEN, COP, PDMS / silicone, epoxy resin or acrylate resin.
• the microlenses 19 and 23 can finally be produced by nanoprinting (nanoprint).
• each microlens is replaced by another type of optical element of micrometric size, in particular a Fresnel lens of micrometric size, a lens with a gradient of index of micrometric size or a size diffraction grating. micrometric.
• the microlenses are converging lenses each having a focal length f of between 1 ⁇ m and 100 ⁇ m, preferably between 1 ⁇ m and 50 ⁇ m.
• all the microlenses 19 are substantially identical and all the microlenses 23 are substantially identical.
• the layer 45 is a filling layer which conforms to the shape of the microlenses 23.
• the layer 45 can be obtained from an optically transparent adhesive (Optically Clear Adhesive - OCA), in particular an adhesive.
• optically transparent liquid Liquid Optically Clear Adhesive - LOCA
• the layer 45 is made of a material having a low refractive index, lower than that of the material of the microlenses 23.
• the difference between the refractive index of the material of the lenses 23 and the index of refraction of the material of the layer 45 is preferably between 0.5 and 0.1.
• the difference between the refractive index of the material of the lenses 23 and the refractive index of the material of the layer 45 is more preferably of the order of 0.15.
• Layer 45 may be of a filler material which is a transparent non-adhesive material.
• the layer 45 corresponds to a film which is applied against the array of microlenses 23, for example an OCA film.
• the contact zone between the layer 45 and the microlenses 23 can be reduced, for example limited to the tops of the microlenses 23.
• the openings 41 are filled with air or with a filling material at least partially transparent to the radiation detected by the photodetectors, for example PDMS, an epoxy or acrylate resin or a resin known as the trade name SU8.
• the openings 41 may be filled with a material which is partially absorbing, that is to say absorbing in a part of the spectrum considered for the target area, for example imaging, in order to chromatically filter the filtered rays. angularly by the filter 2.
• the filling material of the openings 41 is opaque to radiation in the near infrared.
• the angular filter 2 preferably has a thickness of the order of 50 mpi.
• the angular filter 2 and the imager 3 are, for example, assembled by an adhesive layer 37.
• Layer 37 is, for example, made of a material chosen from an acrylate glue, an epoxy glue or an OCA.
• Layer 37 is preferably made of an acrylate glue.
• Layer 35 is a refractive index matching layer, that is to say that it makes it possible to reduce the losses of light rays by reflection at the interface between the angular filter (the filling material of the openings 41) and the passivation layer 33.
• Layer 35 is preferably made of a material whose refractive index is situated between the refractive index of layer 33 and the refractive index of the material for filling the openings 41.
• the layer 35 is deposited on the front face of the imager 3 (the upper face in the orientation of FIG. 3) by printing, by transfer of a film (lamination) or by evaporation, at the end of manufacture of the imager 3.
• the layer 37 is deposited on the rear face of the angular filter 2 (the lower face in the orientation of FIG. 3) by printing or by transfer of a film (lamination).
• the layer 37 is deposited on the front face of the layer 35 of the imager 3.
• the assembly of the filter 2 and the imager 3 is, for example, carried out after the deposition of the layer 37 by rolling the filter 2 on the surface of the imager 3 (more particularly on the surface of the layer 35).
• a step of annealing, crosslinking under ultraviolet light or putting under pressure in an autoclave follows the assembly in order to optimize the mechanical adhesion properties.
• the device 101 comprises an additional layer, for example, between the filter 2 and the imager 3.
• This layer corresponds to an infrared filter making it possible to filter the radiation whose lengths waveforms are greater than 600 nm.
• the transmittance of this infrared filter is preferably less than 0.1% (Optical density of 3 or OD3 (Optical Density)).
• the process for forming at least some layers may correspond to a so-called additive process, for example by direct printing of the material making up the layers at the desired locations, in particular in the form of sol-gel, for example by inkjet printing, heliography, screen printing, flexography, spray coating or drop-casting.
• the process for forming at least some layers may correspond to a so-called subtractive process, in which the material making up the layers is deposited on the entire structure and in which the unused portions are then removed, for example by photolithography or laser ablation.
• the deposition on the entire structure can be carried out for example by liquid, by cathodic sputtering or by evaporation. They may in particular be processes of the spin coating, spray coating, heliography, die coating, blade coating, flexography or screen printing type.
• the layers are metallic, the metal is, for example, deposited by evaporation or by cathodic sputtering on the entire support and the metal layers are delimited by etching
• the layers can be produced by printing techniques.
• the materials of these layers described above can be deposited in liquid form, for example in the form of conductive and semiconductor inks using inkjet printers.
• the term “materials in liquid form” is understood here also to mean gel materials which can be deposited by printing techniques.
• Annealing steps are optionally provided between the depositions of the different layers, but the annealing temperatures may not exceed 150 ° C., and the deposition and any annealing may be carried out at atmospheric pressure.
• FIG. 4 represents, in a partial and schematic sectional view, another embodiment of the image acquisition device illustrated in FIG. 2.
• Figure 4 shows an image acquisition device 102 similar to the image acquisition device 101 illustrated in Figure 3 with the difference that the array of second lenses comprises lenses 23 'smaller than the lenses 23 ( Figure 3).
• the number of lenses 23 'in the device 102 is preferably greater than the number of openings 41 (in the XY plane).
• the number of lenses 23 ′ is four times greater than the number of openings 41.
• the lenses 23 ′ have, according to the embodiment illustrated in FIG. 4, a diameter smaller than the diameter w1 of the openings 41. . [0100]
• An advantage of the embodiment illustrated in FIG. 4 is that it does not require alignment of the second array of lenses 23 'on the array of openings 41.
• FIG. 5 represents, in a partial and schematic sectional view, yet another embodiment of the example of the image acquisition device illustrated in FIG. 2.
• FIG. 5 represents an image acquisition device 103 similar to the image acquisition device 101 illustrated in FIG. 3 with the difference that the matrix structure 21 comprises a third array of lenses 47.
• the third array of plano-convex lenses 47 serves for the collimation of the light transmitted by the array of apertures 41 coupled to the second array of lenses 23.
• the plane faces of the lenses 47 face the plane faces of the lenses 23.
• the third network is located between layer 211 and imager 3.
• the number of lenses 47 of the third array is equal to the number of lenses 23 of the second array.
• the lenses 47 of the third array and the lenses 23 of the second array are aligned by their optical axes.
• the number of lenses 47 of the third array is greater than the number of lenses 23 of the second array.
• the lenses 47 are contiguous or not contiguous.
• the rays emerge from the lenses 23 and from the layer 211 at an angle with respect to the respective direction of the rays incident to the lenses 23.
• the angle is specific to a lens 23 and depends on the diameter of the latter and the distance. focal length of this same lens 23.
• the rays meet the lenses 47 of the third network.
• the rays are thus deflected, at the output of the lenses 47, by an angle b with respect to the respective directions of the rays incident to the lenses 47.
• the angle b is specific to a lens 47 and depends on the diameter of the latter and the distance focal length of this same lens 47.
• a total angle of divergence corresponds to the deviations generated successively by the lenses 23 and by the lenses 47.
• the lenses 47 of the third array are chosen so that the total angle of divergence is, for example, less than or equal to approximately 5 °.
• FIG. 5 illustrates an ideal configuration in which the image focal planes of the lenses 23 of the second array coincide with the object focal planes of the lenses 47 of the third array.
• the rays shown, arriving parallel to the optical axis, are focused at the image focal point of the lens 23 or object focal point of the lens 47.
• the rays which emerge from the lens 47 thus propagate parallel to the optical axis of the latter. .
• the total divergence angle is, in this case, zero.
• the third lens array 47 is, in Figure 5, located under and in contact with a seventh layer 40.
• the seventh layer 40 resulting from the filling of the openings 41, covers the rear faces of the walls 39.
• the third lens array 47 is located on and in contact with the rear face of the walls 39.
• the openings 41 are, then, filled with air or with a filling material.
• the lenses 47 and the lenses 23 are of the same composition or of different compositions. According to the embodiment of FIG. 5, the rear face of the lenses 47 is covered by an eighth filling layer 49. Layer 49 and layer 45 can be of the same composition or of different compositions. Layer 49 preferably has a refractive index lower than the refractive index of the lens material 47.
• FIG. 6 represents, in a partial and diagrammatic sectional view, yet another embodiment of the example of the image acquisition device illustrated in FIG. 2.
• FIG. 6 represents an image acquisition device 104 similar to the image acquisition device 103 illustrated in FIG. 5 with the difference that it comprises lenses 47 'smaller than the lenses. 47 (figure 5).
• the number of lenses 47 'in the device 104 is preferably greater than the number of openings 41.
• the number of lenses 47' is four times greater than the number of openings 41. (in the XY plane).
• An advantage of the embodiment illustrated in FIG. 6 is that it does not require alignment of the third array of lenses 47 'on the array of openings 41.
• FIG. 7 represents, in a partial and diagrammatic sectional view, yet another embodiment of the example of the acquisition device illustrated in FIG. 2.
• FIG. 7 represents an image acquisition device 105 similar to the image acquisition device 103 illustrated in FIG. 5 with the difference that the third array of lenses 47 "is located between the second lens array 23 and the layer 211 of openings 41.
• the device 105 comprises a filling layer 51 covering the rear face of the lenses 47.
• the layer 51 is similar to the layer 49 of the device 103 illustrated in FIG. 5 except that it rests on the upper face of layer 211.
• FIG. 8 represents, in a partial and schematic sectional view, yet another embodiment of the example of the acquisition device illustrated in FIG. 2.
• FIG. 8 represents an image acquisition device 106 similar to the image acquisition device 101 illustrated in FIG. 3 with the difference that the matrix structure 21 comprises a ninth layer 213 consisting of a second matrix of openings 53 delimiting walls 55 opaque to radiation 27 (FIG. 2).
• the layer 213 is located under and in contact with the seventh layer 40 resulting from the filling of the openings 41 with the filling material.
• the seventh layer 40 covers the rear faces of the walls 39.
• the layer 213 is located on and in contact with the rear face of the walls 39.
• the openings 41 are, then, filled with air or with a filling material.
• the openings 53 have, for example, substantially the same shape as the openings 41 with the difference that the dimensions of the openings 41 and 53 may be different.
• the walls 55 have, for example, substantially the same shape and the same composition as the walls 39 with the difference that the dimensions of the walls 39 and 55 may be different.
• the layer 213 comprises a number of openings 53 substantially identical to the number of openings 41 present in the matrix of the layer 211.
• the number of openings 41 is identical to the number of openings 53.
• Each opening 41 is preferably aligned with an opening 53, for example the center of each opening 41 is aligned with the center of an opening 53.
• the openings 53 and the openings 41 have the same dimensions, that is to say that the openings 53 have a diameter "w2" (measured at the base of the openings, ie. that is to say at the interface with the layer 40) substantially identical to the diameter wl of the openings 41.
• the diameters wl and w2 are identical.
• the walls 55 have, for example, a height h2 substantially identical to the height h of the walls 39.
• the heights h and h2 are identical.
• the diameters w1 and w2 are different.
• the diameter w2 is preferably smaller than the diameter w1.
• the heights h and h2 are different.
• the openings 53 are filled with air or, preferably, with a filling material of composition similar to the filling material of the openings 41. Even more preferably, the filling material fills the gaps. Openings 53 and form a layer 57 on the rear face of the walls 55.

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• Spectroscopy & Molecular Physics (AREA)
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• Condensed Matter Physics & Semiconductors (AREA)
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• Solid State Image Pick-Up Elements (AREA)
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• 2020
  • 2020-02-18 FR FR2001613A patent/FR3107363A1/fr active Pending
• 2021
  • 2021-02-09 EP EP21703282.0A patent/EP4107558A1/de not_active Withdrawn
  • 2021-02-09 US US17/798,859 patent/US20230154957A1/en not_active Abandoned
  • 2021-02-09 CN CN202180015154.6A patent/CN115136034A/zh active Pending
  • 2021-02-09 WO PCT/EP2021/053011 patent/WO2021165089A1/fr unknown
  • 2021-02-09 JP JP2022549745A patent/JP2023513953A/ja active Pending
  • 2021-02-09 KR KR1020227030043A patent/KR20220140763A/ko unknown
  • 2021-02-18 TW TW110105434A patent/TW202138849A/zh unknown
  • 2021-02-18 CN CN202120377890.3U patent/CN215118902U/zh active Active

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