# US 10,310,171 B2 · Planar illumination apparatus > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,310,171 B2 - Document ID: US10310171B2 - Status: Granted - Kind: B2 - Application number: 15/893,881 - Filed: 2018-02-12 - Published: 2018-08-23 - Granted: 2019-06-04 - Earliest claimed: 2017-02-22 - Assignees: MINEBEA MITSUMI Inc. - Applicants: MINEBEA MITSUMI Inc. - Inventors: Toru Kunimochi - Web page: https://patentgrep.com/patent/US10310171B2 ## CPC - G02B 6/0088: {of the light guide or other optical sheets in the package} - G02F 1/133308: {Support structures for LCD panels, e.g. frames or bezels} - G02F 1/133524: {Light-guides, e.g. fibre-optic bundles, louvered or jalousie light-guides} - G02F 1/133608: {including particular frames or supporting means} - G02F 1/133615: {Edge-illuminating devices, i.e. illuminating from the side} - G02F 1/133314: {Back frames} - G02F 1/133317: {Intermediate frames, e.g. between backlight housing and front frame} - G02F 1/13332: {Front frames} - G02F 1/133562: {on the viewer side} - G02B: OPTICAL ELEMENTS, SYSTEMS OR APPARATUS - 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 ## Abstract A planar illumination apparatus according to an embodiment includes: a frame including a bottom surface that is curved as viewed in a cross section, and a side wall that is provided in a standing manner so as to surround a circumference of the bottom surface; a light guide plate that is housed in the frame, that is curved along the bottom surface as viewed in the cross section, and that includes an emission surface for emitting light; and a plurality of optical sheets that are arranged along the emission surface of the light guide plate and that overlap with one another in a plan view. An end portion of at least one of the plurality of optical sheets is fixed to an upper end surface of the side wall of the frame via a fixing member. ## Claims ### Claim 1 A planar illumination apparatus comprising: a frame including a bottom surface that is curved as viewed in a cross section, and a side wall that is provided in a standing manner so as to surround a circumference of the bottom surface; a light guide plate that is housed in the frame, that is curved along the bottom surface as viewed in the cross section, and that includes an emission surface for emitting light; and a plurality of optical sheets that are arranged along the emission surface of the light guide plate and that overlap with one another as viewed in a plan view, wherein an end portion of at least one of the plurality of optical sheets is fixed to an upper end surface of the side wall of the frame via a fixing member, wherein the one of the optical sheets is an optical sheet located farthest from the emission surface, and wherein end portions of the optical sheets other than the optical sheet located farthest are arranged in a notch portion provided on an inner peripheral side of the side wall. ### Claim 2 (depends on 1) The planar illumination apparatus according to claim 1, wherein the one of the optical sheets is an optical sheet located farthest from the emission surface, the optical sheets other than the optical sheet located farthest include convex portions that extend in a horizontal direction with respect to the optical sheets, at different positions on end portions, and the convex portions are fixed, via fixing members, to upper surfaces of notch portions that are provided at positions corresponding to the convex portions on an upper end surface side of the side wall. ### Claim 3 (depends on 1) The planar illumination apparatus according to claim 1, further comprising: a light shielding sheet that defines an effective region of the emission surface, wherein the light shielding sheet is arranged so as to cover at least the end portion fixed to the frame. ### Claim 4 (depends on 1) The planar illumination apparatus according to claim 1, wherein the fixing member is at least one of a double-sided tape and an adhesive agent. ### Claim 5 A planar illumination apparatus comprising: a frame including a bottom surface that is curved as viewed in a cross section, and a side wall that is provided in a standing manner so as to surround a circumference of the bottom surface; a light guide plate that is housed in the frame, that is curved along the bottom surface as viewed in the cross section, and that includes an emission surface for emitting light; and a plurality of optical sheets that are arranged along the emission surface of the light guide plate and that overlap with one another as viewed in a plan view, wherein an end portion of at least one of the plurality of optical sheets is fixed to an upper end surface of the side wall of the frame via a fixing member, wherein the frame is configured such that a thickness between an upper end surface and a lower end surface of the side wall is thinner than a thickness of the light guide plate, and the one of the optical sheets is an optical sheet located closest to the emission surface. ### Claim 6 (depends on 5) The planar illumination apparatus according to claim 5, wherein end portions of the optical sheets other than the optical sheet located closest are fixed to the frame by fixing members via an end portion of the optical sheet located closest. ### Claim 7 (depends on 6) The planar illumination apparatus according to claim 6, wherein the fixing members are arranged at positions that do not overlap with one another as viewed in a plan view. ### Claim 8 (depends on 5) The planar illumination apparatus according to claim 5, wherein the optical sheets other than the optical sheet located closest have convex portions that extend in a horizontal direction with respect to the optical sheets, at different positions on end portions, and the convex portions are fixed to the optical sheet located closest by fixing members. ### Claim 9 (depends on 5) The planar illumination apparatus according to claim 5, further comprising: a light shielding sheet that defines an effective region of the emission surface, wherein the light shielding sheet is arranged so as to cover at least the end portion fixed to the frame. ### Claim 10 (depends on 5) The planar illumination apparatus according to claim 5, wherein the fixing member is at least one of a double-sided tape and an adhesive agent. ### Claim 11 A planar illumination apparatus comprising: a frame including a bottom surface that is curved as viewed in a cross section, and a side wall that is provided in a standing manner so as to surround a circumference of the bottom surface; a light guide plate that is housed in the frame, that is curved along the bottom surface as viewed in the cross section, and that includes an emission surface for emitting light; and a plurality of optical sheets that are arranged along the emission surface of the light guide plate and that overlap with one another as viewed in a plan view, wherein an end portion of at least one of the plurality of optical sheets is fixed to an upper end surface of the side wall of the frame via a fixing member, wherein the frame includes a tapered surface that is inclined in a direction in which the upper end surface of the side wall is separated from the emission surface of the light guide plate, the one of the optical sheets is an optical sheet located closest to the emission surface, and an end portion of the optical sheet is fixed to the tapered surface. ### Claim 12 (depends on 11) The planar illumination apparatus according to claim 11, wherein end portions of the optical sheets other than the optical sheet located closest are fixed to the frame by fixing members via the end portion of the optical sheet located closest. ### Claim 13 (depends on 11) The planar illumination apparatus according to claim 11, further comprising: a light shielding sheet that defines an effective region of the emission surface, wherein the light shielding sheet is arranged so as to cover at least the end portion fixed to the frame. ### Claim 14 (depends on 11) The planar illumination apparatus according to claim 11, wherein the fixing member is at least one of a double-sided tape and an adhesive agent. ### Claim 15 A planar illumination apparatus comprising: a frame including a bottom surface that is curved as viewed in a cross section, and a side wall that is provided in a standing manner so as to surround a circumference of the bottom surface; a light guide plate that is housed in the frame, that is curved along the bottom surface as viewed in the cross section, and that includes an emission surface for emitting light; a plurality of optical sheets that are arranged along the emission surface of the light guide plate and that overlap with one another as viewed in a plan view, wherein an end portion of at least one of the plurality of optical sheets is fixed to an upper end surface of the side wall of the frame via a fixing member; and a light shielding sheet that defines an effective region of the emission surface, wherein the light shielding sheet is arranged so as to cover at least the end portion fixed to the frame, and wherein end portions of the optical sheets other than the optical sheet located farthest are arranged in a notch portion provided on an inner peripheral side of the side wall. ### Claim 16 (depends on 15) The planar illumination apparatus according to claim 15, wherein the fixing member is at least one of a double-sided tape and an adhesive agent.