# US 9,753,432 B2 · Optical head for hologram optical apparatus and method of operating the same > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 9,753,432 B2 - Document ID: US9753432B2 - Status: Granted - Kind: B2 - Application number: 14/079,983 - Filed: 2013-11-14 - Published: 2014-05-15 - Granted: 2017-09-05 - Earliest claimed: 2012-11-14 - Assignees: Samsung Electronics Co., Ltd. - Applicants: Samsung Electronics Co., Ltd. - Inventors: Kyoung-seok Pyun; Chil-sung Choi; Alexander Morozov; Jung-kwuen An; Sun-il Kim; Ivan Bovsunovskiy; Andrew Putilin - Web page: https://patentgrep.com/patent/US9753432B2 ## CPC - G03H 1/0402: {Recording geometries or arrangements (G03H1/0443, G03H1/0476, G03H1/16 take precedence)} - G03H 1/0476: {Holographic printer (G03H1/268 takes precedence)} - G03H 1/16: using Fourier transform ({G03H1/10}, G03H1/12, G03H1/14 take precedence; analogue computers G06G, e.g. G06G7/19) - G03H 2001/048: {Parallel printer, i.e. a fringe pattern is reproduced} - G03H 2210/22: 2D SLM object wherein the object beam is formed of the light modulated by the SLM - G03H 2222/18: RGB trichrome light - G03H 2222/34: Multiple light sources - G03H 2223/16: Optical waveguide, e.g. optical fibre, rod - 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 optical head for a hologram optical apparatus and a method of operating the same are provided. The optical head for the hologram optical apparatus includes a reference light unit for guiding reference light, a signal light unit for guiding signal light, and a light source unit for providing 1 the reference light and the signal light to the reference light unit and the signal light unit, wherein the reference light unit and the signal light unit are stacked. The signal light unit includes: a plurality of optical waveguides stacked sequentially; composite hologram optical elements and lighting hologram optical elements disposed on the plurality of optical waveguides; an optical modulator for modulating light output from the plurality of the optical waveguides; and a lens for condensing light output from the optical modulator onto a recording layer. ## Claims ### Claim 1 An optical head for a hologram optical apparatus, the optical head comprising: a reference light unit which generates a reference light for hologram recording; a signal light unit which generates a signal light for hologram recording; and a light source unit which provides light to the reference light unit and the signal light unit, wherein the reference light unit and the signal light unit are vertically stacked; and wherein the signal light unit comprises: a single optical waveguide onto which the signal light from the light source unit is incident; a composite hologram optical element and a lighting hologram optical element, each comprising a three layer hologram corresponding to red, green, and blue light, disposed on the single optical waveguide; a single optical modulator which modulates light output from the single optical waveguide; and a lens which condenses light emitted from the single optical modulator onto the hologram recording layer. ### Claim 2 (depends on 1) The optical head for a hologram optical apparatus according to claim 1, wherein the lens comprises a holographic Fourier lens. ### Claim 3 (depends on 1) The optical head for a hologram optical apparatus according to claim 1, wherein the reference light generating unit comprises: an optical waveguide; an upper composite hologram optical element disposed on a top surface of the optical waveguide; and a lower composite hologram optical element disposed on a bottom surface of the optical waveguide. ### Claim 4 (depends on 3) The optical head for a hologram optical apparatus according to claim 3, wherein the upper and lower composite hologram optical elements, each comprise a three layer hologram. ### Claim 5 (depends on 1) The optical head for a hologram optical apparatus according to claim 1, wherein the light source unit comprises: a first light source, a second light source, and a third light source; a reflection unit which reflects light emitted from the first light source, the second light source, and the third light source; and a mirror which reflects light from the reflection unit to the signal light unit. ### Claim 6 (depends on 5) The optical head for a hologram optical apparatus according to claim 5, wherein the first light source comprises a first laser which emits light of a first color, the second light source comprises a second laser which emits light of a second color, different from the first color, and the third light source comprises a third laser which emits light of a third color, different from the first color and the second color. ### Claim 7 (depends on 6) The optical head for a hologram optical apparatus according to claim 6, wherein the first laser is one of a continuous wave (CW) laser and a quasi CW laser, the second laser is one of a CW laser and a quasi-CW laser, and the third laser is one of a CW laser and a quasi-CW laser. ### Claim 8 (depends on 5) The optical head for a hologram optical apparatus according to claim 5, wherein the reflection unit comprises a mirror and a beam splitter. ### Claim 9 An optical head for a hologram optical apparatus, the optical head comprising: a reference light unit which generates a reference light for hologram recording; a signal light unit which generates a signal light for hologram recording; and a light source unit which provides light to the reference light unit and the signal light unit, wherein the reference light unit and the signal light unit are vertically stacked, and wherein the signal light unit comprises: a plurality of optical waveguides stacked vertically; a composite hologram optical element and a lighting hologram optical element, each comprising a single layer hologram, disposed on each of the plurality of optical waveguides; an optical modulator which modulates light output from the plurality of optical waveguides; and a lens which condenses light emitted from the optical modulator onto the hologram recording layer. ### Claim 10 (depends on 9) The optical head for a hologram optical apparatus according to claim 9, wherein the plurality of optical waveguides comprises an optical waveguide for red light, an optical waveguide for green light, and an optical waveguide for blue light, wherein the optical waveguide for red light, the optical waveguide for green light, and the optical waveguide for blue light are vertically stacked. ### Claim 11 (depends on 9) The optical head for a hologram optical apparatus according to claim 9, wherein the composite hologram optical element and the lighting hologram optical element are both disposed on one of a top surface and a bottom surface of each of the plurality of optical waveguides. ### Claim 12 (depends on 9) The optical head for a hologram optical apparatus according to claim 9, wherein the lens comprises a Fourier lens. ### Claim 13 (depends on 9) The optical head for a hologram optical apparatus according to claim 9, wherein the composite hologram optical elements do not overlap each other in a vertical direction. ### Claim 14 (depends on 13) The optical head for a hologram optical apparatus according to claim 13, wherein the light source unit comprises a first light source, a second light source, and a third light source, wherein each of the first light source, the second light source, and the third light source directs light to the composite hologram optical element disposed on one of the plurality of optical waveguides. ### Claim 15 (depends on 9) The optical head for a hologram optical apparatus according to claim 9, wherein thicknesses of the composite hologram optical elements are the same. ### Claim 16 (depends on 9) The optical head for a hologram optical apparatus according to claim 9, wherein thicknesses of the lighting hologram optical elements are the same. ### Claim 17 (depends on 9) The optical head for a hologram optical apparatus according to claim 9, wherein thicknesses of the composite hologram optical element and the lighting hologram optical element disposed on each of the optical waveguides are the same. ### Claim 18 (depends on 9) The optical head for a hologram optical apparatus according to claim 9, wherein refractive index modulations of the composite hologram optical elements are the same. ### Claim 19 A method of operating an optical head of a hologram optical apparatus, the method comprising: a light source unit generating reference light and signal light; a reference light unit directing the reference light from the light source unit to a hologram recording layer; a signal light unit directing the signal light from the light source unit to the hologram recording layer; wherein the reference light generating unit and the signal light generating unit are vertically stacked; wherein the signal light generating unit comprises an optical waveguide, a composite hologram optical element disposed on the optical waveguide, and a lighting hologram optical element disposed on the optical waveguide; and wherein the method further comprises adjusting at least one of a thickness and a refractive index modulation of the composite hologram optical element. ### Claim 20 (depends on 19) The method according to claim 19, wherein the optical waveguide comprises a plurality of optical waveguides which are vertically stacked; and wherein a composite hologram optical element and a lighting hologram optical element, each comprising a single layer hologram, are disposed on each of the optical waveguides. ### Claim 21 (depends on 20) The method according to claim 20, wherein the composite hologram optical elements do not overlap each other. ### Claim 22 (depends on 21) The method according to claim 21, wherein the light source unit generating the reference light and the scanning light comprises the light source unit illuminating each of the composite hologram optical elements at certain time intervals. ### Claim 23 (depends on 19) The method according to claim 19, wherein the composite hologram optical element and the lighting hologram optical element each comprise a three layer hologram.