# US 2019/0379868 A1 · Information Display Device and Information Display Method > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2019/0379868 A1 - Document ID: US20190379868A1 - Status: Published application - Kind: A1 - Application number: 16/551,250 - Filed: 2019-08-26 - Published: 2019-12-12 - Earliest claimed: 2017-02-28 - Assignees: Huawei Technologies Co., Ltd. - Applicants: Huawei Technologies Co., Ltd. - Inventors: Tao Lin; Pengcheng Zhou; Yan Li - Web page: https://patentgrep.com/patent/US20190379868A1 ## CPC - H04N 9/3173: {wherein the projection device is specially adapted for enhanced portability} - G02B 6/02085: {characterised by the grating profile, e.g. chirped, apodised, tilted, helical} - G02B 27/0103: {comprising holographic elements} - G02B 27/0172: {characterised by optical features} - G03H 1/12: Spatial modulation, e.g. ghost imaging - H04N 9/3102: {using two-dimensional electronic spatial light modulators (micromechanical modulators as such G02B26/0833; liquid crystal modulators as such G02F1/13)} - G02B 6/124: Geodesic lenses or integrated gratings - G02B 2027/012: {comprising devices for attenuating parasitic image effects} - G02B 2027/0127: {comprising devices increasing the depth of field} - G02B 2027/0134: {of stereoscopic type} - G02B 2027/0174: {holographic} - H04N: PICTORIAL COMMUNICATION, e.g. TELEVISION - 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 An information display device includes a spatial light modulator, configured to emit a holographic three-dimensional light field to a first grating, where the holographic three-dimensional light field corresponds to at least two focal planes, the first grating, configured to deflect the holographic three-dimensional light field emitted by the spatial light modulator, so that the holographic three-dimensional light field is propagated along a first direction and transmitted into an optical waveguide, the optical waveguide, configured to receive the holographic three-dimensional light field transmitted from the first grating, and propagate the holographic three-dimensional light field in the optical waveguide, and a second grating, configured to deflect the holographic three-dimensional light field that is propagated in the optical waveguide. ## Claims ### Claim 1 An information display device, comprising: a first grating; an optical waveguide; a spatial light modulator configured to emit a holographic three-dimensional light field toward the first grating, wherein the holographic three-dimensional light field corresponds to at least two focal planes, and wherein the first grating is configured to deflect the holographic three-dimensional light field into the optical waveguide, wherein the optical waveguide is configured to propagate the transmitted holographic three-dimensional light field; a second grating comprising a separation hole and configured to deflect three-dimensional object light into the holographic three-dimensional light field that is propagated by the optical waveguide, wherein the optical waveguide is configured to emit out the three-dimensional object light, wherein the first grating is further configured to focus, at the separation hole, zero-order light in the holographic three-dimensional light field that comes from the spatial light modulator, and wherein the separation hole is configured to absorb the zero-order light after focusing the zero-order light in the holographic three-dimensional light field. ### Claim 2 (depends on 1) The information display device according to claim 1, wherein the second grating is further configured to magnify the holographic three-dimensional image for display when the holographic three-dimensional image is located within a 1× focal length of the second grating. ### Claim 3 (depends on 1) The information display device according to claim 1, wherein the first grating is disposed between the spatial light modulator and the optical waveguide, and wherein the first grating is configured to deflect the holographic three-dimensional light field when the holographic three-dimensional light field penetrates the first grating. ### Claim 4 (depends on 1) The information display device according to claim 1, wherein the optical waveguide is disposed between the first grating and the spatial light modulator, and wherein the first grating is configured to reflect the holographic three-dimensional light field. ### Claim 5 (depends on 1) The information display device according to claim 1, wherein the second grating is disposed between the spatial light modulator and the optical waveguide, wherein and wherein the second grating is configured to deflect the holographic three-dimensional light field when the holographic three-dimensional light field penetrates the second grating. ### Claim 6 (depends on 1) The information display device according to claim 1, wherein the optical waveguide is disposed between the spatial light modulator and the second grating, and wherein the second grating is configured to reflect the holographic three-dimensional light field. ### Claim 7 An information display method, comprising: emitting a holographic three-dimensional light field to a first grating using a spatial light modulator, wherein the holographic three-dimensional light field corresponds to at least two focal planes; deflecting, using the first grating, the holographic three-dimensional light field into an optical waveguide; propagating, using the optical waveguide, the holographic three-dimensional light field; and deflecting, using a second grating, three-dimensional object light into the holographic three-dimensional light field that is propagated by the optical waveguide; emitting, by the optical waveguide, out the three-dimensional object light focusing, at a separation hole of the second grating, using the first grating, zero-order light in the holographic three-dimensional light field from the spatial light modulator; and absorbing the zero-order light using the separation hole or propagating, using the separation hole, the zero-order light in the optical waveguide in a total reflection manner after focusing the zero-order light in the holographic three-dimensional light field. ### Claim 8 (depends on 7) The method according to claim 7, wherein the holographic three-dimensional image is located within a 1× focal length of the second grating, further comprising magnifying, by the second grating, the holographic three-dimensional image for display. ### Claim 9 (depends on 7) The method according to claim 7, wherein the first grating is disposed between the spatial light modulator and the optical waveguide, and wherein the method further comprises: enabling, by the first grating, the holographic three-dimensional light field to penetrate the first grating; and deflecting the holographic three-dimensional light field. ### Claim 10 (depends on 7) The method according to claim 7, wherein the optical waveguide is disposed between the first grating and the spatial light modulator, and wherein the method further comprises reflecting, using the first grating, the holographic three-dimensional light field emitted by the spatial light modulator. ### Claim 11 (depends on 7) The method according to claim 7, wherein the second grating is disposed between the spatial light modulator and the optical waveguide, and wherein the method further comprises: enabling, by the second grating, the holographic three-dimensional light field to penetrate the second grating; and deflecting the holographic three-dimensional light field. ### Claim 12 (depends on 7) The method according to claim 7, wherein the optical waveguide is disposed between the spatial light modulator and the second grating, and wherein the method further comprises reflecting, using the second grating, the holographic three-dimensional light field. ### Claim 13 An information display device, comprising: a first grating; an optical waveguide; a spatial light modulator configured to emit a holographic three-dimensional light field towards the first grating, wherein the holographic three-dimensional light field corresponds to at least two focal planes, and wherein the first grating is configured to deflect the holographic three-dimensional light field into the optical waveguide, wherein the optical waveguide is configured to propagate the transmitted holographic three-dimensional light field; a second grating comprising a separation hole and configured to deflect three-dimensional object light into the holographic three-dimensional light field that is propagated by the optical waveguide, wherein the optical waveguide is configured to emit out the three-dimensional object light, wherein the first grating is further configured to focus, at the separation hole, zero-order light in the holographic three-dimensional light field that comes from the spatial light modulator, and wherein the separation hole is configured to propagate the zero-order light in the optical waveguide in a total reflection manner after focusing the zero-order light in the holographic three-dimensional light field. ### Claim 14 (depends on 13) The information display device according to claim 13, wherein the second grating is further configured to magnify the holographic three-dimensional image for display when the holographic three-dimensional image is located within a 1× focal length of the second grating. ### Claim 15 (depends on 13) The information display device according to claim 13, wherein the first grating is disposed between the spatial light modulator and the optical waveguide, and wherein the first grating is configured to deflect the holographic three-dimensional light field when the holographic three-dimensional light field penetrates the first grating. ### Claim 16 (depends on 13) The information display device according to claim 13, wherein the optical waveguide is disposed between the first grating and the spatial light modulator, and wherein the first grating is configured to reflect the holographic three-dimensional light field. ### Claim 17 (depends on 13) The information display device according to claim 13, wherein the second grating is disposed between the spatial light modulator and the optical waveguide, and wherein the second grating is configured to deflect the holographic three-dimensional light field when the holographic three-dimensional light field penetrates the second grating. ### Claim 18 (depends on 13) The information display device according to claim 13, wherein the optical waveguide is disposed between the spatial light modulator and the second grating, and wherein the second grating is configured to reflect the holographic three-dimensional light field. ### Claim 19 (depends on 13) The information display device according to claim 13, wherein the second grating is disposed between the spatial light modulator and the optical waveguide. ### Claim 20 (depends on 13) The information display device according to claim 13, wherein the optical waveguide is disposed between the spatial light modulator and the second grating.