# US 10,120,334 B2 · Self-reference holographic imaging system > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,120,334 B2 - Document ID: US10120334B2 - Status: Granted - Kind: B2 - Application number: 14/439,630 - Filed: 2013-10-28 - Published: 2015-10-15 - Granted: 2018-11-06 - Earliest claimed: 2012-10-30 - Assignees: Centre National De La Recherche Scientifique; Universite Du Maine, Institut Des Molecules Et Materiaux Du Mans (Immm-Umr 6283) - Applicants: Centre National De La Recherche Scientifique; Universite Du Maine, Institut Des Molecules Et Materiaux Du Mans - Inventors: Pascal Picart; Mokrane Malek - Web page: https://patentgrep.com/patent/US10120334B2 ## CPC - G03H 1/0443: {Digital holography, i.e. recording holograms with digital recording means (holobject computation G03H1/0866)} - G03H 1/0011: {for security or authentication (holograms on information-bearing cards B42D25/328; testing papers with holograms G07D7/0032)} - G03H 1/28: superimposed holograms only - G03H 1/265: {Angle multiplexing; Multichannel holograms (G03H1/268 takes precedence)} - G03H 2001/005: {in microscopy, e.g. digital holographic microscope [DHM]} - G03H 2001/0447: {In-line recording arrangement} - G03H 2001/045: {Fourier or lensless Fourier arrangement} - G03H 2001/0458: {Temporal or spatial phase shifting, e.g. parallel phase shifting method} - G03H 2001/266: {Wavelength multiplexing} - G03H 2225/12: 2D SLM - G03H 2225/32: Phase only - G03H 2227/03: Means for moving one component (G03H1/0476, G03H2001/2695 take precedence) - G03H: HOLOGRAPHIC PROCESSES OR APPARATUS (holograms, e.g. point holograms, used as ordinary optical elements G02B5/32; producing stereoscopic or other three-dimensional effects G02B30/00; diffraction-grating systems G02B27/44; systems using moiré fringes G02B27/60; optical logic elements G02F3/00; stereo-photography G03B35/00; photosensitive materials or processes for photographic purposes G03C; {stereo-photographic or similar processes G03C9/00}; apparatus for processing exposed photographic materials G03D; analogue computers performing mathematical operations with the aid of optical elements G06E3/00; authentication by radiation, of concealed information carried by holograms or diffraction gratings G06K19/16; holographic storage G11B7/0065, G11C13/04; {stereoscopic or other three dimensional effects in television systems H04N13/00}) ## Abstract A system for recording a digital hologram of an object comprises: a coherent source intended to illuminate the object and thus produce a wave diffracted by the object; and a digital sensor intended to record the digital hologram of the object. It furthermore comprises a spatial phase modulating assembly able to produce in the plane of the sensor a plurality of duplicates of the wave diffracted by the object, the duplicates being offset from each other but overlapping partially, these duplicates forming on the sensor a digital hologram of the object, this hologram being what is referred to as a self-reference hologram. ## Claims ### Claim 1 A system for recording a digital hologram of an object, comprising: a partially coherent or coherent source intended to illuminate the object and thus produce a wave diffracted by the object; and a digital sensor intended to record the digital hologram of the object, characterized in that it furthermore comprises a spatial phase modulating assembly consisting of: a spatial phase modulator located between the object and the sensor, associated with: a first image-forming device able to form an image A″ of the object at a non-zero distance Δz1 from the spatial phase modulator; and a second image-forming device able to form: an image of the plane of the spatial phase modulator in a plane located at a non-zero distance Δz2 from a plane of the sensor; and an image A′ of the image A″ of the object, in a plane located at a distance Δz′ from the plane of the sensor, the modulating assembly being able to produce in the plane of the sensor a plurality of identical duplicates of the wave diffracted by the object, said identical duplicates being offset from each other but overlapping partially, the identical duplicates forming on the sensor a digital hologram of the object, the hologram being a self-reference hologram. ### Claim 2 (depends on 1) The system for recording a digital hologram as claimed in claim 1, wherein the spatial phase modulator is a periodic grating. ### Claim 3 (depends on 1) The system for recording a digital hologram as claimed in claim 1, wherein the modulating assembly is able to produce 4 duplicates in the plane of the sensor. ### Claim 4 (depends on 1) The system for recording a digital hologram as claimed in claim 1, wherein the source is spatially and/or temporally partially coherent. ### Claim 5 (depends on 1) The system for recording a digital hologram as claimed in claim 1, wherein the partially coherent or coherent source is a multi-wavelength source. ### Claim 6 (depends on 5) The system for recording a digital hologram as claimed in claim 5, wherein the object being intended to be illuminated in a preset direction, it comprises a multi-wavelength source with an illumination direction that is different for each wavelength. ### Claim 7 (depends on 1) The system for recording a digital hologram as claimed in claim 1, wherein the object is intended to be illuminated in transmission or in reflection. ### Claim 8 (depends on 1) The system for recording a digital hologram as claimed in claim 1, further comprising means for modifying the direction of illumination of the object and thus is able to record, for various illumination directions, one hologram per illumination direction. ### Claim 9 (depends on 1) The system for recording a digital hologram as claimed in claim 1, further comprising means for engendering a rotation of the object about a given axis, thus making it possible to record, for various angles of rotation, one hologram per angle of rotation. ### Claim 10 (depends on 1) The system for recording a digital hologram as claimed in claim 1, wherein the sensor is a CCD or CMOS camera. ### Claim 11 (depends on 1) The system for recording a digital hologram as claimed in claim 1, wherein the first image-forming device comprises a cube beam splitter. ### Claim 12 (depends on 11) The system for recording a digital hologram as claimed in claim 11, wherein the first image-forming device furthermore comprises a lens and/or a microscope objective. ### Claim 13 (depends on 11) The system for recording a digital hologram as claimed in claim 11 wherein the second image-forming device comprises the same cube beam splitter.