# US 2014/0192285 A1 · Illumination unit and display unit > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2014/0192285 A1 - Document ID: US20140192285A1 - Status: Published application - Kind: A1 - Application number: 14/234,341 - Filed: 2012-07-20 - Published: 2014-07-10 - Earliest claimed: 2011-07-29 - Assignees: Sony Corporation - Inventors: Shogo Shinkai; Akira Ebisui; Kentaro Okuyama; Harumi Sato - Web page: https://patentgrep.com/patent/US20140192285A1 ## CPC - G02B 30/25: using polarisation techniques - F21V 7/005: {with an elongated shape to cooperate with linear light sources} - F21V 7/043: {with cylindrical surface} - F21V 7/09: with a combination of different curvatures - G02F 1/0105: {Illuminating devices} - H04N 13/302: for viewing without the aid of special glasses, i.e. using autostereoscopic displays - H04N 13/31: using parallax barriers - G02B 6/0053: {Prismatic sheet or layer; Brightness enhancement element, sheet or layer} - G02B 6/0055: {Reflecting element, sheet or layer} - G02B 6/0058: {varying in density, size, shape or depth along the light guide} - G02F 1/1334: based on polymer dispersed liquid crystals, e.g. microencapsulated liquid crystals - G02F 1/133615: {Edge-illuminating devices, i.e. illuminating from the side} - G02F 2201/52: RGB geometrical arrangements - G02B: OPTICAL ELEMENTS, SYSTEMS OR APPARATUS - F21V: FUNCTIONAL FEATURES OR DETAILS OF LIGHTING DEVICES OR SYSTEMS THEREOF; STRUCTURAL COMBINATIONS OF LIGHTING DEVICES WITH OTHER ARTICLES, NOT OTHERWISE PROVIDED FOR - G02F: OPTICAL DEVICES OR ARRANGEMENTS FOR THE CONTROL OF LIGHT BY MODIFICATION OF THE OPTICAL PROPERTIES OF THE MEDIA OF THE ELEMENTS INVOLVED THEREIN; NON-LINEAR OPTICS; FREQUENCY-CHANGING OF LIGHT; OPTICAL LOGIC ELEMENTS; OPTICAL ANALOGUE/DIGITAL CONVERTERS - H04N: PICTORIAL COMMUNICATION, e.g. TELEVISION ## Abstract There are provided an illumination unit capable of reducing formation of a double image in three-dimensional display and a display unit including the same. An illumination optical system configured to generate linear illumination light formed by two-dimensionally arranging a plurality of linear illumination light beams or a plurality of point-like illumination light beams, and a reflective plate configured to reflect the linear illumination light are included. The reflective plate reflects the linear illumination light to or close to a plane passing through a part that generates the linear illumination light and being perpendicular to a plane including the reflective plate. ## Claims ### Claim 1 An illumination unit comprising: an illumination optical system configured to generate linear illumination light formed by two-dimensionally arranging a plurality of linear illumination light beams or a plurality of point-like illumination light beams; and a reflective plate configured to reflect the linear illumination light, wherein the reflective plate reflects the linear illumination light to or close to a plane passing through a part that generates the linear illumination light and being perpendicular to a plane including the reflective plate. ### Claim 2 (depends on 1) The illumination unit according to claim 1, wherein the reflective plate generates reflected light focused on a focal point located on or near a line segment passing through the part that generates the linear illumination light and being parallel to a normal to the plane including the reflective plate, when a light component parallel to a plane perpendicular to the part that generates the linear illumination light of the linear illumination light is considered. ### Claim 3 (depends on 2) The illumination unit according to claim 2, wherein the reflective plate has, directly below the part that generates the linear illumination light, a surface shape where the reflected light is focused. ### Claim 4 (depends on 2) The illumination unit according to claim 2, wherein the reflective plate has a surface shape allowing the reflected light to be focused on a focal point at a position satisfying a following expression: H1/nr−W1≦H2≦1/nr+W1 where H1 is a distance between a first plane including a plurality of apexes formed on a top surface of the reflective plate and the part that generates the linear illumination light, H2 is a distance between the first plane and the position of the focal point, nr is a relative refractive index (n1/n2), n1 is a refractive index of a region between the first plane and the part that generates the linear illumination light, n2 is a refractive index of a region between the first plane and a reflective surface of the reflective plate, and W1 is a width of the part that generates the linear illumination light. ### Claim 5 (depends on 2) The illumination unit according to claim 2, wherein the reflective plate has a surface shape allowing the reflected light to be focused on a focal point located at a position satisfying a following expression: H2=H 1/nr where H1 is a distance between a first plane including a plurality of apexes formed on a top surface of the reflective plate and the part that generates the linear illumination light, H2 is a distance between the first plane and the position of the focal point, nr is a relative refractive index (n1/n2), n1 is a refractive index of a region between the first plane and the part that generates the linear illumination light, and n2 is a refractive index of a region between the first plane and a reflective surface of the reflective plate. ### Claim 6 (depends on 2) The illumination unit according to claim 2, wherein the reflective plate has, as a reflective surface, a part of an inner surface of a cylinder at a position facing the part that generates the linear illumination light. ### Claim 7 (depends on 2) The illumination unit according to claim 2, wherein a pitch of a cubic shape in the reflective surface is equal to a pitch of the part that generates the linear illumination light. ### Claim 8 (depends on 6) The illumination unit according to claim 6, wherein a radius r of a part corresponding to the part of the inner surface of the cylinder in the reflective surface satisfies a following expression: r=(H22+(P1/2)2)1/2 where H2 is a distance between a first plane including a plurality of apexes formed on a top surface of the reflective plate and the position of the focal point, and P1 is a pitch of the part that generates the linear illumination light. ### Claim 9 (depends on 2) The illumination unit according to claim 2, wherein the reflective plate has a surface shape where the reflected light is focused on a focal point located at a position satisfying a following expression (1), and has, as a reflective surface, a part of an inner surface of a cylinder at a position facing the part that generates the linear illumination light, a pitch of a cubic shape in the reflective surface is equal to a pitch of the part that generates the linear illumination light, and a radius r of a part corresponding to the part of the inner surface of the cylinder satisfies a following expression (2): H2=H1/nr (1) r=(H22+(P1/2)2)1/2 (2) where H1 is a distance between a first plane including a plurality of apexes formed on a top surface of the reflective plate and the part that generates the linear illumination light, H2 is a distance between the first plane and the position of the focal point, nr is a relative refractive index (n1/n2), n1 is a refractive index of a region between the first plane and the position of the focal point, n2 is a refractive index of a region between the first plane and the reflective surface of the reflective plate, P1 is a pitch of the part that generates the linear illumination light. ### Claim 10 (depends on 1) The illumination unit according to claim 1, wherein the reflective plate has a regular convex-concave shape with a pitch that is twice or less as large as a width of the part that generates the linear illumination light. ### Claim 11 (depends on 10) The illumination unit according to claim 10, wherein the reflective plate has a regular convex-concave shape with a pitch that is ½ times or less as large as the part that generates the linear illumination light. ### Claim 12 (depends on 10) The illumination unit according to claim 10, wherein the reflective plate has a convex-concave shape in which a plurality of depressions are close-packed, each of the depressions having an inner surface configured of three flat surfaces combined with one another at a predetermined angle. ### Claim 13 (depends on 12) The illumination unit according to claim 12, wherein the depressions are arranged to allow an extending direction of one or two side sections of a hole of each of the depressions and an extending direction of the part that generates the linear illumination light to be orthogonal to each other. ### Claim 14 (depends on 12) The illumination unit according to claim 12, wherein the predetermined angle is an angle within a range of 90°±3.8°. ### Claim 15 (depends on 10) The illumination unit according to claim 10, wherein the reflective plate has a convex-concave shape in which a plurality of strip-like depressions are arranged, each of the strip-like depressions having an inner surface configured of two flat surfaces combined with each other at a predetermined angle. ### Claim 16 (depends on 15) The illumination unit according to claim 15, wherein the predetermined angle is an angle within a range of 90°±3°. ### Claim 17 (depends on 15) The illumination unit according to claim 15, wherein the predetermined angle is an angle within a range where light emitted from a first part generating the linear illumination light is reflected to a second part generating the linear illumination light and being adjacent to the first part. ### Claim 18 (depends on 1) The illumination unit according to claim 1, wherein a reflective surface of the reflective plate is a convex-concave surface, and the reflective plate includes a resin layer that is embedded in the convex-concave surface. ### Claim 19 (depends on 1) The illumination unit according to claim 1, wherein a reflective surface of the reflective plate is a convex-concave surface, and a surface of the convex-concave surface is a mirror surface. ### Claim 20 (depends on 1) The illumination unit according to claim 1, wherein the illumination optical system includes a light guide plate, a reflective surface of the reflective plate is a convex-concave surface, and the reflective plate includes an adhesive layer on an apex of the convex-concave surface, the adhesive layer allowing the apex of the convex-concave surface and the light guide plate to be bonded together. ### Claim 21 (depends on 1) The illumination unit according to claim 1, wherein the illumination optical system includes a light guide plate, and the reflective plate includes an adhesive layer allowing the reflective plate and a part or a whole of an outer edge of the light guide plate to be bonded together. ### Claim 22 (depends on 1) The illumination unit according to claim 1, wherein the illumination optical system includes a first transparent substrate and a second transparent substrate arranged to face each other with the part that generates the linear illumination light in between, an electrode disposed on a surface of at least one of the first transparent substrate and the second transparent substrate, a light source configured to emit light to an end surface of the first transparent substrate, a light modulation layer disposed in a gap between the first transparent substrate and the second transparent substrate, and configured to exhibit a scattering property or transparency with respect to light from the light source, depending on magnitude of an electric field, and a driving section configured to drive the electrode, the light modulation layer exhibits the tranparency with respect to the light from the light source when the electric field is relatively small, and exhibits the scattering property with respect to light from the light source when the electric field is relatively large, and the driving section generates a plurality of first regions exhibiting the scattering property in the light modulation layer by driving the electrode, and then allowing the first regions to emit the linear illumination light. ### Claim 23 (depends on 22) The illumination unit according to claim 22, wherein the driving section generates the first regions in the entire light modulation layer by driving the electrode, and then allows the entire light modulation layer to emit planar illumination light. ### Claim 24 A display unit comprising: a display panel including a plurality of pixels, the pixels being driven based on an image signal; and an illumination unit configured to illuminate the display panel, the illumination unit including an illumination optical system configured to generate linear illumination light formed by two-dimensionally arranging a plurality of linear illumination light beams or a plurality of point-like illumination light beams; and a reflective plate configured to reflect the linear illumination light, wherein the reflective plate reflects the linear illumination light to or close to a plane passing through a part that generates the linear illumination light and being perpendicular to a plane including the reflective plate. ### Claim 25 (depends on 24) The display unit according to claim 24, wherein the illumination unit includes a first transparent substrate and a second transparent substrate arranged to face each other with the part that generates the linear illumination light in between, an electrode disposed on a surface of at least one of the first transparent substrate and the second transparent substrate, a light source configured to emit light to an end surface of the first transparent substrate, a light modulation layer disposed in a gap between the first transparent substrate and the second transparent substrate, and configured to exhibit a scattering property or transparency with respect to light from the light source, depending on magnitude of an electric field, and a driving section configured to drive the electrode, based on an image signal, the light modulation layer exhibits the transparency with respect to the light from the light source when the electric field is relatively small, and exhibits the scattering property with respect to light from the light source when the electric field is relatively large, and the driving section generates a plurality of scattering regions exhibiting the scattering property in the light modulation layer by driving the electrode in a three-dimensional display mode, and then allowing the scattering regions to emit the linear illumination light. ### Claim 26 (depends on 25) The display unit according to claim 25, further comprising a pair of polarizing plates facing each other with the display panel in between, wherein the light modulation layer includes a first region and a second region, the first region having optical anisotropy and relatively high responsivity with respect to an electric field, the second region having optical anisotropy and relatively low responsivity with respect to an electric field, the first region and the second region each mainly have an optical-axis component in a direction parallel to a transmission axis of one polarizing plate located closer to the illumination unit of the pair of polarizing plates, when the light modulation layer exhibits the transparency, and the second region mainly has an optical-axis component in a direction parallel to the transmission axis of the polarizing plate located closer to the illumination unit of the pair of polarizing plate, and the first region has an optical axis in a direction intersecting with or orthogonal to an optical axis of the second region and intersecting with or orthogonal to the first transparent substrate, when the light modulation layer exhibits the scattering property.