# US 11,908,223 B2 · Force sensor and display device including the same > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,908,223 B2 - Document ID: US11908223B2 - Status: Granted - Kind: B2 - Application number: 17/362,928 - Filed: 2021-06-29 - Published: 2022-03-17 - Granted: 2024-02-20 - Earliest claimed: 2020-09-17 - Assignees: Samsung Display Co., Ltd. - Applicants: Samsung Display Co., Ltd. - Inventors: Kwang Hyun Baek; Ji Hun Ryu; Chang Min Park; Jeong An Hong - Web page: https://patentgrep.com/patent/US11908223B2 ## CPC - G06F 3/0412: {Digitisers structurally integrated in a display} - G06V 40/1306: {non-optical, e.g. ultrasonic or capacitive sensing} - G06V 40/1318: {using electro-optical elements or layers, e.g. electroluminescent sensing} - G06V 40/1365: {Matching; Classification} - H10K 59/65: OLEDs integrated with inorganic image sensors - H10K 59/12: Active-matrix OLED [AMOLED] displays - H10K 59/8731: {multilayered coatings having a repetitive structure, e.g. having multiple organic-inorganic bilayers} - G06F: ELECTRIC DIGITAL DATA PROCESSING (computer systems based on specific computational models G06N) - G06V: IMAGE OR VIDEO RECOGNITION OR UNDERSTANDING - H10K: ORGANIC ELECTRIC SOLID-STATE DEVICES ## Abstract A display device includes a display panel; a metal plate and a filling member disposed on a same layer on a bottom surface of the display panel and that include different materials; a fingerprint sensor disposed on a bottom surface of the filling member and that overlaps the filling member; and a member-sensor bonding member disposed between the fingerprint sensor and the filling member and that bonds the fingerprint sensor to the filling member. At least a part of a side surface of the filling member and a side surface of the metal plate are spaced apart from each other with an air gap therebetween. ## Claims ### Claim 1 A display device, comprising: a display panel; a metal plate and a filling member disposed on a same layer on a bottom surface of the display panel, wherein a material of the metal plate differs from a material of the filling member; a fingerprint sensor disposed on a bottom surface of the filling member and that overlaps the filling member; and a bonding member disposed between the fingerprint sensor and the filling member and that bonds the fingerprint sensor to the filling member, wherein at least a part of a side surface of the filling member and a side surface of the metal plate are spaced apart from each other with an air gap therebetween. ### Claim 2 (depends on 1) The display device of claim 1, wherein a thermal expansion coefficient of the filling member is greater than a thermal expansion coefficient of the metal plate. ### Claim 3 (depends on 2) The display device of claim 2, wherein the thermal expansion coefficient of the filling member is at least three times greater than the thermal expansion coefficient of the metal plate. ### Claim 4 (depends on 3) The display device of claim 3, wherein a length of the air gap in an extension direction of the side surface of the metal plate is at least 80% of a length of the side surface of the metal plate. ### Claim 5 (depends on 4) The display device of claim 4, wherein another part of the side surface of the filling member is in direct contact with the side surface of the metal plate. ### Claim 6 (depends on 1) The display device of claim 1, wherein the metal plate includes a through hole that extends from a top surface of the metal plate that faces the bottom surface of the display panel to a bottom surface of the metal plate opposite to the top surface, and the filling member is filled in at least the through hole. ### Claim 7 (depends on 6) The display device of claim 6, wherein the filling member is filled in the through hole by an injection method, and the air gap is formed in consideration of an injection temperature, an injection pressure, and in injection duration. ### Claim 8 (depends on 6) The display device of claim 6, wherein a thickness of the filling member is greater than a thickness of the metal plate, and the filling member partially covers a bottom surface of the metal plate. ### Claim 9 (depends on 6) The display device of claim 6, wherein a width of the through hole decreases from the top surface to the bottom surface. ### Claim 10 (depends on 9) The display device of claim 9, wherein an inclination angle between the bottom surface of the metal plate and the side surface of the metal plate in contact with the through hole ranges from 40° to 50°. ### Claim 11 (depends on 6) The display device of claim 6, wherein a width of the through hole decreases and then increases from the top surface to the bottom surface. ### Claim 12 (depends on 6) The display device of claim 6, wherein a width of the through hole increases and then decreases from the top surface to the bottom surface. ### Claim 13 (depends on 1) The display device of claim 1, wherein the fingerprint sensor includes an ultrasonic fingerprint sensor, and the ultrasonic fingerprint sensor performs fingerprint recognition by comparing an incident ultrasonic wave emitted upward from the ultrasonic fingerprint sensor and a fingerprint reflection ultrasonic wave reflected from the fingerprint, and wherein a thickness of the filling member is adjustable and forms a resonance frequency between the incident ultrasonic wave and an interface reflection ultrasonic wave reflected by an interface between the member-sensor bonding member and the filling member. ### Claim 14 (depends on 1) The display device of claim 1, wherein the fingerprint sensor includes an optical fingerprint sensor, and the filling member has a light transmittance of at least 90%. ### Claim 15 (depends on 1) The display device of claim 1, further comprising: a protective layer disposed between top surfaces of the metal plate and the filling member and a bottom surface of the display panel; and a member-protective layer bonding member that bonds the top surfaces of the metal plate and the filling member to the protective layer. ### Claim 16 A display device, comprising: a display panel; a metal plate and a filling member disposed on same layer on a bottom surface of the display panel, wherein a material of the metal plate differs from a material of the fill in g member; a fingerprint sensor disposed on a bottom surface of the filling member and that overlaps the filling member; and a bonding member disposed between the fingerprint sensor and the filling member and that bonds the fingerprint sensor to the filling member, wherein a side surface of the filling member and a side surface of the metal plate are adjacent to each other. ### Claim 17 (depends on 16) The display device of claim 16, wherein a thermal expansion coefficient of the filling member is greater than a thermal expansion coefficient of the metal plate. ### Claim 18 (depends on 17) The display device of claim 17, wherein the thermal expansion coefficient of the filling member is at least three times greater than the thermal expansion coefficient of the metal plate. ### Claim 19 (depends on 17) The display device of claim 17, further comprising: a buffer member disposed between the side surface of the filling member and the side surface of the metal plate, wherein the side surface of the filling member and the side surface of the metal plate are separated from each other by the buffer member, and a thermal expansion coefficient of the buffer member is less than a thermal expansion coefficient of the filling member. ### Claim 20 (depends on 18) The display device of claim 18, wherein the side surface of the filling member and the side surface of the metal plate are in direct contact with each other, and the filling member further includes a member through hole that penetrates the filling member in a thickness direction, and wherein the member through hole is located between the metal plate and the fingerprint sensor in a plan view. ### Claim 21 (depends on 18) The display device of claim 18, wherein the side surface of the filling member and the side surface of the metal plate are in direct contact with each other, and the metal plate further includes a plate through hole that penetrates the metal plate in a thickness direction, and wherein the plate through hole is located outward from the side surface of the metal plate. ### Claim 22 A display device, comprising: a display panel; a metal plate disposed on a bottom surface of the display panel, wherein the metal plate includes a through hole; and a filling member disposed in the through hole on a same layer as the metal plate on the bottom surface of the display panel, and that includes a different material from the metal plate, wherein at least a part of a side surface of the filling member and a side surface of the metal plate are spaced apart from each other with an air gap therebetween, and wherein a thermal expansion coefficient of the filling member is greater than a thermal expansion coefficient of the metal plate. ### Claim 23 (depends on 22) The display panel of claim 22, further comprising a fingerprint sensor disposed on a bottom surface of the filling member and that overlaps the filling member; and a bonding member disposed between the fingerprint sensor and the filling member and that bonds the fingerprint sensor to the filling member.