# US 11,309,501 B2 · Flexible display device > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,309,501 B2 - Document ID: US11309501B2 - Status: Granted - Kind: B2 - Application number: 16/703,711 - Filed: 2019-12-04 - Published: 2020-08-27 - Granted: 2022-04-19 - Earliest claimed: 2019-02-22 - Assignees: Samsung Display Co., Ltd. - Applicants: Samsung Display Co., Ltd. - Inventors: Kyoungah Lee; MinGu Kim; Hyunsuk Nam; Hyoyul Yoon - Web page: https://patentgrep.com/patent/US11309501B2 ## CPC - H04M 1/0268: {including a flexible display panel} - B32B 3/263: {characterised by a layer having non-uniform thickness} - B32B 5/16: characterised by features of a layer formed of particles, e.g. chips, powder {or granules (layer formed of natural mineral particles B32B19/00; layer being formed of wood fibres, chips or particles B32B21/02)} - B32B 5/18: characterised by features of a layer {of} foamed material - B32B 7/12: using interposed adhesives or interposed materials with bonding properties - B32B 9/007: {comprising carbon, e.g. graphite, composite carbon} - B32B 9/046: {of foam} - B32B 9/048: {made of particles} - B32B 15/046: {of foam} - B32B 15/16: next to a particulate layer - B32B 15/20: comprising aluminium or copper {(B32B15/016 and B32B15/017 take precedence)} - H10K 59/80: Constructional details - H10K 77/111: {Flexible substrates} - B32B 2260/025: Particulate layer - B32B 2260/046: Synthetic resin - B32B 2264/108: Carbon, e.g. graphite particles - B32B 2266/0221: Vinyl resin - B32B 2266/0228: Aromatic vinyl resin, e.g. styrenic (co)polymers - B32B 2266/0235: Vinyl halide, e.g. PVC, PVDC, PVF, PVDF - B32B 2266/025: Polyolefin - B32B 2266/0278: Polyurethane - B32B 2307/212: Electromagnetic interference shielding - B32B 2307/30: having particular thermal properties - B32B 2307/546: Flexural strength; Flexion stiffness - B32B 2307/558: Impact strength, toughness - B32B 2307/71: Resistive to light or to UV - B32B 2307/732: Dimensional properties - B32B 2457/20: Displays, e.g. liquid crystal displays, plasma displays - B32B 2457/206: Organic displays, e.g. OLED - H10K 59/873: {Encapsulations} - H10K 2102/351: {Thickness} - Y02E 10/549: Organic PV cells - H04M: TELEPHONIC COMMUNICATION (circuits for controlling other apparatus via a telephone cable and not involving telephone switching apparatus G08) - B32B: LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM - H10K: ORGANIC ELECTRIC SOLID-STATE DEVICES - Y02E: REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION ## Abstract A flexible display device includes a display panel including a bending area, a first non-bending area, and a second non-bending area, an outer member over a first surface of the display panel, and a stress control member between the display panel and the outer member, and including a first control area overlapping with the bending area, and a second control area and a third control area overlapping with the first non-bending area and the second non-bending area, respectively, such that the first control area is between the second control area and the third control area, and a maximum thickness of the first control area is less than a thickness of an end of the second control area and a thickness of an end of the third control area spaced apart from a bending axis in the second direction. ## Claims ### Claim 1 A flexible display device comprising: a display panel comprising a bending area bendable about a bending axis extending in a first direction, and a first non-bending area and a second non-bending area arranged to be spaced apart from each other in a second direction crossing the first direction with the bending area between the first non-bending area and the second non-bending area; an outer member over a first surface of the display panel; and a stress control member between the display panel and the outer member, and comprising a first control area overlapping with the bending area and a second control area and a third control area overlapping with the first non-bending area and the second non-bending area, respectively, such that the first control area is between the second control area and the third control area, wherein a maximum thickness of the first control area is less than a thickness of an end of the second control area spaced apart from the first control area in the second direction and a thickness of an end of the third control area spaced apart from the first control area in the second direction. ### Claim 2 (depends on 1) The flexible display device of claim 1, wherein the stress control member comprises: a first surface contacting the outer member, and a second surface opposite to the first surface of the stress control member, and wherein, in a non-bending state, the first surface of the stress control member is a flat surface and the second surface is a curved surface. ### Claim 3 (depends on 2) The flexible display device of claim 2, wherein the display panel comprises an opposite surface that is opposite to the first surface of the display panel, wherein the second surface contacts the opposite surface, and wherein the opposite surface has a shape corresponding to the second surface. ### Claim 4 (depends on 2) The flexible display device of claim 2, wherein the stress control member has a thickness which gradually increases as the stress control member is farther away from the bending axis in the second direction. ### Claim 5 (depends on 4) The flexible display device of claim 4, wherein the thickness of the stress control member linearly increases. ### Claim 6 (depends on 1) The flexible display device of claim 1, wherein a portion which overlaps with the bending axis in the first direction, of the first control area, is defined as a central portion, and the central portion has a thickness in a range of 50 μm or more to 150 μm or less. ### Claim 7 (depends on 1) The flexible display device of claim 1, wherein each of the end of the second control area and the end of the third control area has a thickness in a range of 150 μm or more to 300 μm or less. ### Claim 8 (depends on 1) The flexible display device of claim 1, wherein the first control area has a uniform thickness. ### Claim 9 (depends on 8) The flexible display device of claim 8, wherein each of the second control area and the third control area has a thickness which linearly increases as the second control area and the third control area, respectively, is farther away from the bending axis in the second direction. ### Claim 10 (depends on 8) The flexible display device of claim 8, wherein each of the second control area and the third control area has a thickness which nonlinearly increases as the second control area and the third control area, respectively, is farther away from the bending axis in the second direction. ### Claim 11 (depends on 1) The flexible display device of claim 1, wherein the stress control member comprises a pressure sensitive adhesive. ### Claim 12 (depends on 1) The flexible display device of claim 1, wherein the stress control member contacts the outer member. ### Claim 13 (depends on 1) The flexible display device of claim 1, further comprising an additional member between the outer member and the display panel and comprising an organic material. ### Claim 14 A flexible display device comprising: a display panel comprising a bending area bendable about a bending axis extending in a first direction, and a first non-bending area and a second non-bending area spaced apart from each other in a second direction crossing the first direction with the bending area between the first non-bending area and the second non-bending area; an outer member over a first surface of the display panel; and a stress control member between the display panel and the outer member and comprising a first surface contacting the outer member and a second surface opposite to the first surface of the stress control member, wherein, in a non-bending state, the first surface of the stress control member is a flat surface and the second surface is a curved surface. ### Claim 15 (depends on 14) The flexible display device of claim 14, wherein the stress control member comprises: a first control area overlapping with the bending area and a second control area and a third control area overlapping with the first non-bending area and the second non-bending area, respectively, such that the first control area is between the second control area and the third control area, and wherein a maximum thickness of the first control area is less than a thickness of an end of the second control area spaced apart from the first control area in the second direction and a thickness of an end of the third control area spaced apart from the first control area in the second direction. ### Claim 16 (depends on 15) The flexible display device of claim 15, wherein the stress control member has a thickness which gradually increases as the stress control member is farther away from the bending axis in the second direction. ### Claim 17 (depends on 15) The flexible display device of claim 15, wherein the first control area has a uniform thickness. ### Claim 18 (depends on 15) The flexible display device of claim 15, wherein a portion which overlaps with the bending axis in the first direction, of the first control area, is defined as a central portion, wherein the central portion has a thickness in a range of 50 μm or more to 150 μm or less, and wherein the end of each of the second control area and the third control area has a thickness in a range of 150 μm or more to 300 μm or less. ### Claim 19 (depends on 14) The flexible display device of claim 14, wherein the display panel comprises an opposite surface that is opposite to the first surface of the display panel, wherein the second surface contacts the opposite surface, and wherein the opposite surface has a shape corresponding to the second surface. ### Claim 20 (depends on 14) The flexible display device of claim 14, wherein the stress control member comprises a pressure sensitive adhesive.