# US 8,570,628 B2 · Three-dimensional color display apparatuses and methods > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 8,570,628 B2 - Document ID: US8570628B2 - Status: Granted - Kind: B2 - Application number: 12/461,845 - Filed: 2009-08-26 - Published: 2010-03-11 - Granted: 2013-10-29 - Earliest claimed: 2008-09-08 - Assignees: Samsung Electronics Co., Ltd. - Applicants: Ji-deog Kim - Inventors: Ji-deog Kim - Web page: https://patentgrep.com/patent/US8570628B2 ## CPC - G02B 5/1866: {Transmission gratings characterised by their structure, e.g. step profile, contours of substrate or grooves, pitch variations, materials (G02B5/1809, G02B5/1828, G02B5/1833, G02B5/1838 and G02B5/1847 take precedence)} - G02B 5/32: Holograms used as optical elements - G02B 26/106: {having diffraction gratings as scanning elements, e.g. holographic scanners (holographic optical elements G02B5/32, holography G03H)} - G02B 30/00: Optical systems or apparatus for producing three-dimensional [3D] effects, e.g. stereoscopic images (in microscopes G02B21/22) - G03H 1/0248: {Volume holograms} - G03H 1/04: Processes or apparatus for producing holograms (G03H1/26 takes precedence) - G03H 1/22: Processes or apparatus for obtaining an optical image from holograms (G03H1/26 - G03H1/34 take precedence) - G03H 1/28: superimposed holograms only - G03H 1/2249: {Holobject properties} - G03H 2001/0439: {for recording Holographic Optical Element [HOE]} - G03H 2001/2271: {RGB holobject} - G03H 2001/2292: {Using scanning means} - G03H 2001/2297: {using frame sequential, e.g. for reducing speckle noise} - G03H 2210/30: 3D object - G03H 2210/45: Representation of the decomposed object - G02B: OPTICAL ELEMENTS, SYSTEMS OR APPARATUS - 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 three-dimensional (3D) color display apparatus may include: light sources emitting different color beams; a volume diffractive element, in which a hologram is recorded using one of the color beams that is emitted from one of the light sources as a reference beam and a signal beam, displaying color images by diffracting the color beams emitted from the light sources; and a scanning unit scanning the color beams diffracted by the volume diffractive element. A 3D color image display method may include: recording holograms in a volume diffractive element using a first color beam as a reference and signal beam; irradiating the first color beam and another color beam onto the volume diffractive element as a reproducing reference beam; forming beam spots by diffracting the first color beam and the another color beam using the volume diffractive element; and scanning the color beams diffracted by the volume diffractive element. ## Claims ### Claim 1 A three-dimensional (3D) color display apparatus, comprising: a plurality of light sources configured to emit different color beams; a volume diffractive element, in which a hologram is recorded using one of the color beams that is emitted from one of the plurality of light sources as a reference beam and a signal beam, configured to display color images by diffracting the color beams emitted from the plurality of light sources; and a scanning unit configured to scan the color beams to be diffracted or being diffracted by the volume diffractive element; wherein each of the plurality of light sources comprises light emission points having an array structure, and wherein a light beam from the plurality of light sources is directly modulated in a propagating direction of the light beam by controlling turning on or turning off of the light emission points. ### Claim 2 (depends on 1) The 3D color display apparatus of claim 1, wherein the volume diffractive element has a polygonal cross-section having a shape of a hexagon or a shape having a greater number of corners than a hexagon. ### Claim 3 (depends on 1) The 3D color display apparatus of claim 1, wherein the volume diffractive element has a polygonal cross-section having an even number of corners. ### Claim 4 (depends on 1) The 3D color display apparatus of claim 1, wherein the color beams emitted from the plurality of light sources are incident to the volume diffractive element so as to satisfy Bragg matching conditions. ### Claim 5 (depends on 1) The 3D color display apparatus of claim 1, wherein the scanning unit comprises a double-axial rotating mirror disposed between the plurality of light sources and the volume diffractive element. ### Claim 6 (depends on 1) The 3D color display apparatus of claim 1, wherein the scanning unit comprises a driver for rotating the volume diffractive element. ### Claim 7 (depends on 1) The 3D color display apparatus of claim 1, wherein a beam from the volume diffractive element is scanned using a phase conjugated hologram method. ### Claim 8 (depends on 1) The 3D color display apparatus of claim 1, further comprising: a beam expander expanding cross-sections of the different color beams emitted from the plurality of light sources. ### Claim 9 (depends on 1) The 3D color display apparatus of claim 1, wherein the reference beam and the signal beam are incident to surfaces of the volume diffractive element, and wherein the surfaces are neighboring surfaces. ### Claim 10 (depends on 1) The 3D color display apparatus of claim 1, further comprising: a Fourier lens or an f-θ lens focusing the color beams diffracted by the volume diffractive element. ### Claim 11 (depends on 1) The 3D color display apparatus of claim 1, wherein the volume diffractive element is formed of a photorefractive crystal, a photorefractive polymer, or an optical polymer. ### Claim 12 (depends on 1) The 3D color display apparatus of claim 1, wherein the plurality of light sources form an array structure. ### Claim 13 A three-dimensional (3D) color image display method, comprising: recording a hologram in a volume diffractive element using a first color beam from a first light source as a reference beam and a signal beam; irradiating the first color beam and another color beam that is different from the first color beam onto the volume diffractive element as a reproducing reference beam, wherein the another color beam is emitted by a second light source; forming beam spots by diffracting the first color beam and the another color beam using the volume diffractive element; and scanning the color beams to be diffracted or being diffracted by the volume diffractive element; wherein both the first light source and the second light source comprise light emission points having an array structure, and wherein the first color beam and the another color beam are directly modulated in a propagating direction of the first color beam and the another color beam by controlling turning on or turning off of the light emission points. ### Claim 14 (depends on 13) The 3D color image display method of claim 13, wherein the volume diffractive element has a polygonal cross-section having a shape of a hexagon or a shape having a greater number of corners than a hexagon. ### Claim 15 (depends on 13) The 3D color image display method of claim 13, wherein the volume diffractive element has a polygonal cross-section having an even number of corners. ### Claim 16 (depends on 13) The 3D color image display method of claim 13, wherein the first color beam and the another color beam are incident to the volume diffractive element so as to satisfy Bragg matching conditions. ### Claim 17 (depends on 13) The 3D color image display method of claim 13, wherein scanning the color beams comprises: rotating the volume diffractive element. ### Claim 18 (depends on 13) The 3D color image display method of claim 13, wherein a beam from the volume diffractive element is scanned using a phase conjugated hologram method. ### Claim 19 (depends on 13) The 3D color image display method of claim 13, wherein the reference beam and the signal beam are incident to surfaces of the volume diffractive element, and wherein the surfaces are neighboring surfaces. ### Claim 20 (depends on 13) The 3D color image display method of claim 13, wherein scanning the color beams comprises: changing an angle formed by the reference beam and the signal beam.