# US 10,768,430 B2 · Display device and head-mounted display > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,768,430 B2 - Document ID: US10768430B2 - Status: Granted - Kind: B2 - Application number: 16/368,157 - Filed: 2019-03-28 - Published: 2019-10-03 - Granted: 2020-09-08 - Earliest claimed: 2018-03-29 - Assignees: Sharp Kabushiki Kaisha - Applicants: Sharp Kabushiki Kaisha - Inventors: Yuuichi Kanbayashi; Naru Usukura; Hiromi Katoh - Web page: https://patentgrep.com/patent/US10768430B2 ## CPC - G02B 27/0172: {characterised by optical features} - G02B 3/08: with discontinuous faces, e.g. Fresnel lens {(diffractive Fresnel lenses G02B5/1876)} - G02B 5/0205: {characterised by the diffusing properties} - G02B 5/045: {Prism arrays} - G02B 5/3025: {Polarisers, i.e. arrangements capable of producing a definite output polarisation state from an unpolarised input state (G02B5/3008, G02B5/3016 take precedence)} - G02B 19/0014: {at least one surface having optical power} - G02B 2027/0123: {comprising devices increasing the field of view} - G02B: OPTICAL ELEMENTS, SYSTEMS OR APPARATUS ## Abstract A display device includes a display panel having a display surface and a lighting device that supplies light to the display panel. The lighting device includes a light source, and an optical member having at least a light exit surface through which the light emitted by the light source exits toward the display surface of the display panel. The optical member includes a light refraction portion that imparts an anisotropic refraction effect to at least light rays exiting through an edge section of the light exit surface to be oriented toward a center side of the display surface. The display device further includes a low refraction index layer interposed between the display panel and the optical member, and the low refraction index layer has a refraction index lower than at least a refraction index of the optical member. ## Claims ### Claim 1 A display device comprising: a display panel having a display surface that displays an image; and a lighting device that supplies light to the display panel, wherein the lighting device includes a light source, and an optical member having at least a light exit surface through which the light emitted by the light source exits toward the display surface of the display panel, the optical member includes a light refraction portion that imparts an anisotropic refraction effect to at least light rays exiting through an edge section of the light exit surface to be oriented toward a center side of the display surface, the display device further comprises a low refraction index layer interposed between the display panel and the optical member, the low refraction index layer having a refraction index lower than at least a refraction index of the optical member, the light refraction portion is formed by a Fresnel lens arranged on a light incident surface of the optical member, and the Fresnel lens has a curvature relatively larger at an outer peripheral end side of the light exit surface than at a central side of the light exit surface. ### Claim 2 (depends on 1) The display device according to claim 1, further comprising a light guide plate including a light incident end surface that is a part of an outer peripheral end surface of the light guide plate and through which the light emitted by the light source enters, and a light exit plate surface that is one of a pair of plate surfaces of the light guide plate and through which the light exits, the light guide plate being arranged to be overlapped with the optical member and arranged at a side opposite to a side of the display panel, wherein the optical member includes a light incident surface facing the light exit plate surface of the light guide plate, and the light refraction portion is arranged on the light incident surface, the light refraction portion includes prisms each of which extends along an orthogonal direction orthogonal to a normal direction of the light incident end surface and has an apex part and a pair of inclined surfaces interposing the apex part, the prisms being aligned along the normal direction, and the prisms include at least an apex part eccentric prism arranged at an end side of the light incident surface in the normal direction, the apex part eccentric prism having the apex part eccentric to be close to an end of the light incident surface in the normal direction. ### Claim 3 (depends on 1) The display device according to claim 1, further comprising: a light guide plate including the light incident end surface and a light exit plate surface, the light incident surface being at least a part of an outer peripheral end surface of the light guide plate and through which the light emitted by the light source enters, and the light exit plate surface being one of a pair of plate surfaces of the light guide plate and through which the light exits, the light guide plate being arranged to be overlapped with the optical member, and an anisotropic light condensing member interposed between the light guide plate and the optical member, wherein the anisotropic light condensing member includes an anisotropic light condensing layer that imparts an anisotropic light condensing effect to light such that a light condensing degree in the normal direction of the light incident end surface is made larger and a light condensing degree in an orthogonal direction orthogonal to the normal direction is made smaller. ### Claim 4 (depends on 3) The display device according to claim 3, further comprising a diffusion member interposed between the display panel and the low refraction index layer to diffuse the light exiting through the light exit surface of the optical member, wherein the diffusion member includes an anisotropic diffusion layer that imparts an anisotropic diffusion effect to the light such that a light diffusion degree in the normal direction is made smaller and a light diffusion degree in the orthogonal direction is made larger. ### Claim 5 (depends on 1) The display device according to claim 1, further comprising a diffusion member interposed between the display panel and the low refraction index layer to diffuse the light emitted from the light exit surface of the optical member. ### Claim 6 (depends on 5) The display device according to claim 5, wherein the diffusion member includes at least a diffusion layer that diffuses light and a polarizing reflection layer that polarizes and reflects light. ### Claim 7 (depends on 1) The display device according to claim 1, further comprising a support member that supports at least the display panel from a side of the optical member. ### Claim 8 (depends on 1) The display device according to claim 1, wherein the low refraction index layer is a resin layer formed of a synthetic resin material. ### Claim 9 A display device comprising: a display panel having a display surface that displays an image; a lighting device that supplies light to the display panel; and a light guide plate; wherein the lighting device includes a light source, and an optical member having at least a light exit surface through which the light emitted by the light source exits toward the display surface of the display panel, the optical member includes a light refraction portion that imparts an anisotropic refraction effect to at least light rays exiting through an edge section of the light exit surface to be oriented toward a center side of the display surface, the display device further comprises a low refraction index layer interposed between the display panel and the optical member, the low refraction index layer having a refraction index lower than at least a refraction index of the optical member, the light guide plate includes a light incident end surface that is a part of an outer peripheral end surface of the light guide plate and through which the light emitted by the light source enters, and a light exit plate surface that is one of a pair of plate surfaces of the light guide plate and through which the light exits, the light guide plate being arranged to be overlapped with the optical member and arranged at a side opposite to a side of the display panel, wherein the optical member includes a light incident surface facing the light exit plate surface of the light guide plate, and the light refraction portion is arranged on the light incident surface, the light refraction portion includes prisms each of which extends along an orthogonal direction orthogonal to a normal direction of the light incident end surface and has an apex part and a pair of inclined surfaces interposing the apex part, the prisms being aligned along the normal direction, and the prisms include at least an apex part eccentric prism arranged at an end side of the light incident surface in the normal direction, the apex part eccentric prism having the apex part eccentric to be close to an end of the light incident surface in the normal direction. ### Claim 10 (depends on 9) The display device according to claim 9, further comprising: a light guide plate including the light incident end surface and a light exit plate surface, the light incident surface being at least a part of an outer peripheral end surface of the light guide plate and through which the light emitted by the light source enters, and the light exit plate surface being one of a pair of plate surfaces of the light guide plate and through which the light exits, the light guide plate being arranged to be overlapped with the optical member, and an anisotropic light condensing member interposed between the light guide plate and the optical member, wherein the anisotropic light condensing member includes an anisotropic light condensing layer that imparts an anisotropic light condensing effect to light such that a light condensing degree in the normal direction of the light incident end surface is made larger and a light condensing degree in an orthogonal direction orthogonal to the normal direction is made smaller. ### Claim 11 (depends on 10) The display device according to claim 10, further comprising a diffusion member interposed between the display panel and the low refraction index layer to diffuse the light exiting through the light exit surface of the optical member, wherein the diffusion member includes an anisotropic diffusion layer that imparts an anisotropic diffusion effect to the light such that a light diffusion degree in the normal direction is made smaller and a light diffusion degree in the orthogonal direction is made larger. ### Claim 12 (depends on 9) The display device according to claim 9, further comprising a diffusion member interposed between the display panel and the low refraction index layer to diffuse the light emitted from the light exit surface of the optical member. ### Claim 13 (depends on 12) The display device according to claim 12, wherein the diffusion member includes at least a diffusion layer that diffuses light and a polarizing reflection layer that polarizes and reflects light. ### Claim 14 (depends on 9) The display device according to claim 9, further comprising a support member that supports at least the display panel from a side of the optical member. ### Claim 15 (depends on 9) The display device according to claim 9, wherein the low refraction index layer is a resin layer formed of a synthetic resin material. ### Claim 16 A display device comprising: a display panel having a display surface that displays an image; a lighting device that supplies light to the display panel; and a light guide plate, wherein the lighting device includes a light source, and an optical member having at least a light exit surface through which the light emitted by the light source exits toward the display surface of the display panel, the optical member includes a light refraction portion that imparts an anisotropic refraction effect to at least light rays exiting through an edge section of the light exit surface to be oriented toward a center side of the display surface, the display device further comprises a low refraction index layer interposed between the display panel and the optical member, the low refraction index layer having a refraction index lower than at least a refraction index of the optical member, the light guide plate includes a light incident end surface and a light exit plate surface, the light incident surface being at least a part of an outer peripheral end surface of the light guide plate and through which the light emitted by the light source enters, and the light exit plate surface being one of a pair of plate surfaces of the light guide plate and through which the light exits, the light guide plate being arranged to be overlapped with the optical member, and an anisotropic light condensing member interposed between the light guide plate and the optical member, wherein the anisotropic light condensing member includes an anisotropic light condensing layer that imparts an anisotropic light condensing effect to light such that a light condensing degree in the normal direction of the light incident end surface is made larger and a light condensing degree in an orthogonal direction orthogonal to the normal direction is made smaller. ### Claim 17 (depends on 16) The display device according to claim 16, further comprising a diffusion member interposed between the display panel and the low refraction index layer to diffuse the light exiting through the light exit surface of the optical member, wherein the diffusion member includes an anisotropic diffusion layer that imparts an anisotropic diffusion effect to the light such that a light diffusion degree in the normal direction is made smaller and a light diffusion degree in the orthogonal direction is made larger. ### Claim 18 (depends on 16) The display device according to claim 16, further comprising a diffusion member interposed between the display panel and the low refraction index layer to diffuse the light emitted from the light exit surface of the optical member. ### Claim 19 (depends on 18) The display device according to claim 18, wherein the diffusion member includes at least a diffusion layer that diffuses light and a polarizing reflection layer that polarizes and reflects light. ### Claim 20 (depends on 16) The display device according to claim 16, further comprising a support member that supports at least the display panel from a side of the optical member. ### Claim 21 (depends on 16) The display device according to claim 16, wherein the low refraction index layer is a resin layer formed of a synthetic resin material.