Bendable display device

Abstract

The present invention discloses a bendable display device, which includes a first display area, a second display area and a bendable area connecting the first display area and the second display area. The bendable display device includes a support film, a flexible substrate arranged on the support film, a display layer arranged on the flexible substrate, a control unit arranged under the support film, and a biometric recognition sensing structure electrically connected to the control unit.

Description

[0001] This application is a divisional application of the invention patent application with the application date of November 14, 2019, application number 201911115041.4, and invention name “Operation method of bendable display device and electronic device”. Technical Field

[0002] The present invention relates to a bendable display device, and in particular to a bendable display device with a biometric recognition sensing structure and a related electronic device. Background Art

[0003] In recent years, bendable electronic devices have become one of the development focuses of the new generation of electronic technology. Bendable electronic devices can provide portability when in a folded state and have a relatively large display area when in an unfolded state. Therefore, bendable electronic devices can have a variety of applications in electronic displays for televisions, screens, mobile computing devices (such as smart phones, tablets, personal computers and e-book readers) and wearable devices (such as smart watches). For this reason, bendable electronic devices can store a large amount of information including personal privacy. In order to protect personal privacy, it is necessary to develop biometric technology. However, in traditional technology, only a small number of biometric sensors will be integrated into electronic devices, so the sensing area is limited and confined to a small specific area. In traditional bendable electronic devices, the limited number and / or setting area of ​​biometric sensors limit the use and security applications of the device, so that the protection of information of different security levels stored in the electronic device is limited. Therefore, how to increase access restrictions is still a very important issue. Summary of the invention

[0004] One of the objectives of the present invention is to provide a bendable display device, wherein the bendable display device includes a biometric sensing structure.

[0005] In one embodiment, the present invention provides a bendable display device. The bendable display device includes a first display area, a second display area, and a bendable area connecting the first display area and the second display area. The bendable display device includes a flexible substrate, a display layer disposed on the flexible substrate, and a biometric sensing structure disposed on the flexible substrate. The biometric sensing structure has a biometric sensing area. The ratio of the area of ​​the biometric sensing area to the area of ​​the flexible substrate ranges from 0.6 to 1.

[0006] In one embodiment, the present invention provides a bendable electronic device. The bendable electronic device includes a first area, a second area, and a bendable area connecting the first area and the second area. The bendable electronic device includes a flexible substrate, an electronic layer disposed on the flexible substrate, and a biometric sensing structure disposed on the flexible substrate. The biometric sensing structure has a biometric sensing area. The ratio of the area of ​​the biometric sensing area to the area of ​​the flexible substrate ranges from 0.6 to 1.

[0007] In one embodiment, the present invention provides an operation method of an electronic device, the operation method comprising: providing an electronic device having a standby state, wherein the electronic device comprises a bendable display device, the bendable display device comprises a flexible substrate, a display layer disposed on the flexible substrate, and a biometric sensing structure disposed on the flexible substrate; when a touch signal is provided to the bendable display device, executing a detection procedure to confirm whether the touch signal meets a predetermined condition; and when the touch signal meets the predetermined condition, starting a biometric sensing mode. The ratio of the area of ​​a biometric sensing region of the biometric sensing structure to the area of ​​the flexible substrate ranges from 0.6 to 1.

[0008] In one embodiment, the present invention provides a bendable display device. The bendable display device includes a first display area, a second display area, and a bendable area connecting the first display area and the second display area. The bendable display device includes a support film, a flexible substrate disposed on the support film, a display layer disposed on the flexible substrate, a control unit disposed under the support film, and a biometric sensing structure electrically connected to the control unit. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] Figure 1 FIG. 1 is a schematic top view of an electronic device according to a first embodiment of the present invention.

[0010] Figure 2 for Figure 1 A schematic cross-sectional view of an electronic device is shown.

[0011] Figure 3 for Figure 1 A schematic cross-sectional view of an electronic device with greater detail is shown.

[0012] Figure 4 for Figure 1 A partial enlarged cross-sectional schematic diagram of an electronic device is shown.

[0013] Figure 5 for Figure 1 A schematic diagram of a biometric sensing area of ​​an electronic device is shown.

[0014] Figure 6FIG. 1 is a schematic top view of an electronic device according to a first embodiment of the present invention.

[0015] Figure 7 FIG. 4 is a schematic top view of an electronic device according to a second embodiment of the present invention.

[0016] Figure 8 for Figure 7 A schematic cross-sectional view of an electronic device is shown.

[0017] Fig. 9 FIG. 4 is a cross-sectional diagram of an electronic device according to a third embodiment of the present invention.

[0018] Fig.10 for Fig. 9 A schematic top view of an electronic device is shown.

[0019] Fig.11 for Fig.10 The electronic device shown is a schematic cross-sectional view and a partially enlarged schematic view with more detailed components.

[0020] Fig.12 It is a schematic top view of an electronic device according to a first variation of the third embodiment of the present invention.

[0021] Fig.13 It is a partially enlarged cross-sectional schematic diagram of an electronic device according to a second variation of the third embodiment of the present invention.

[0022] Fig.14 FIG. 4 is a cross-sectional diagram of an electronic device according to a fourth embodiment of the present invention.

[0023] Fig.15 FIG. 5 is a schematic top view of an electronic device according to a fifth embodiment of the present invention.

[0024] Fig.16 FIG. 4 is a cross-sectional diagram of an electronic device according to a sixth embodiment of the present invention.

[0025] Fig.17 FIG. 4 is a flow chart of an operating method of an electronic device according to a seventh embodiment of the present invention.

[0026] Explanation of reference numerals: 100-bendable display device; 102-first conductive layer; 1021-first layer; 1022-second layer; 1023-third layer; 102L-first wire; 102r, 104r-opening; 104-second conductive layer; 104L-second wire; 106-recessed portion; 110, 120-protective layer; 112-insulating layer; 122-protective glue; 124-covering layer; 132-circuit layer; 1321-first insulating layer; 1322-second insulating layer; 1323-flat layer; 134-light-emitting structure; 136-PIN layer; 138-lower electrode; 140-upper electrode; 150-recessed; 190-electronic layer; 212-control unit; 224-flexible electrode Circuit board; 300, 351, 352, 353-display unit; 301-first electrode; 302-second electrode; 310-light-emitting layer; 320, 108-dielectric layer; 334-third insulating layer; 336-light-emitting diode; 500-dashed line; 61-first side; 62-second side; AR-active area; AR1-first active area; AR2-second active area; B1-first boundary; B2-second boundary; BR-biometric sensing area; BSS-biometric sensing structure; BSS1-first biometric sensing structure; BSS2-second biometric sensing structure; BSS3-third biometric sensing structure; BSU, BSU1, BSU3, BSU2-sensing unit; BX1 , BX2-bending axis; CNL-connecting line; CP-center point; CR1, CR2-bending part; D1, D2, D3-direction; d1, d2-minimum distance; DE1, DE2-drain; DL-display layer; DR-display area; DR1-first display area; DR2-second display area; E1, E2-electrode; ED-electronic device; FA, FB, FC, FD, FE, FF, Fa, Fb, Fc, Fd-sensing result pattern; FL1-first flat area; FL2-second flat area; FR-bendable area; FX-bending axis; G1, G2-gate; H1, H2-height; L-light; LS1, LS2-shading part; M1-first metal layer; M2-second Two metal layers; M3-third metal layer; M4-fourth metal layer; NR-non-active region; OS-outer surface; P1-first surface portion; P2-second surface portion; P3-third surface portion; PH1, PH2, PH3, PH4-pinholes; PL-separation layer; PLN1, PLN2-plane; r1, r2, r3-region; S1, S2, d3, d4-spacer; SE1, SE2-source; SL1, SL2-semiconductor layer; SUB-flexible substrate; SUF-support film; SUF1-first support film; SUF2-second support film; SW1-edge; T1-driving thin film transistor; T2-sensing thin film transistor; w1-first distance; w2-second distance; w3-third distance;W1, W2-width; 4-4', 8-8'-tangent. ; DETAILED DESCRIPTION

[0027] The present invention can be understood by referring to the following detailed description in conjunction with the accompanying drawings. It should be noted that in order to facilitate the reader's understanding and the simplicity of the drawings, the multiple drawings in the present invention only depict a portion of the display device, and certain elements in the drawings are not drawn according to the actual scale. In addition, the number and size of each element in the drawings are only for illustration and are not intended to limit the scope of the present invention.

[0028] Certain words are used throughout the specification and claims of the present invention to refer to specific components. It should be understood by those skilled in the art that electronic equipment manufacturers may refer to the same components by different names. It is not intended to distinguish between components that have the same function but different names. In the following specification and claims, the words "including" and "comprising" are open-ended words and should therefore be interpreted as "including but not limited to...".

[0029] It should be understood that when an element or film layer is referred to as being "on" or "connected to" another element or film layer, it may be directly on or directly connected to the other element or layer, or there may be an intervening element or film layer between the two. Conversely, when an element is referred to as being "directly" "on" or "directly connected to" another element or film layer, there may be no intervening element or film layer between the two.

[0030] It should be noted that the embodiments listed below can replace, reorganize, and mix the technical features in several different embodiments to complete other embodiments without departing from the spirit of the present invention.

[0031] Please refer to Figures 1 to 6 , Figure 1 is a schematic top view of an electronic device according to a first embodiment of the present invention, Figure 2 for Figure 1 A schematic cross-sectional view of an electronic device shown in FIG. Figure 3 for Figure 1 A schematic cross-sectional view of the electronic device shown with more details, Figure 4 for Figure 1 A partially enlarged cross-sectional schematic diagram of an electronic device shown in FIG. Figure 5 for Figure 1 A schematic diagram of a biometric sensing area of ​​an electronic device is shown, Figure 6 It is a schematic top view of an electronic device according to a first embodiment of the present invention, illustrating the arrangement of a display unit and a biometric identification sensing structure.

[0032] like Figure 1 and Figure 2As shown, the electronic device ED of the present invention may be a bendable electronic device ED, and may be bent between 180 degrees and -180 degrees along the bending axis FX. For example, Figure 2 The bendable electronic device ED in the figure shows a state of being bent inward, and the bending angle is 180 degrees. The bendable electronic device ED includes a first flat area FL1, a second flat area FL2, and a bendable area FR connecting the first flat area FL1 and the second flat area FL2. The portion of the bendable electronic device ED in the bendable area FR can be curled (curved, rolled), bent (bent) and / or folded (folded). In some embodiments, the bendable electronic device ED may include more than one bendable area FR. In addition, the electronic device ED can be divided into an active area AR and a non-active area NR adjacent to the active area AR, for example, the non-active area NR may surround the active area AR. The active area AR may include a first active area AR1 located in the first flat area FL1, a second active area AR2 located in the second flat area FL2, and a bendable area FR.

[0033] Please refer to Figure 2 , the bendable electronic device ED of the present invention may include a flexible substrate SUB and an electronic layer 190 disposed on the flexible substrate SUB. According to some embodiments, the electronic layer 190 may be a display layer DL. According to some embodiments, the electronic layer 190 may not have a display function. For example, the electronic layer 190 may include an antenna, such as a liquid crystal antenna. In this case, the electronic layer 190 may include a dielectric layer and a circuit layer, wherein the dielectric layer may be a liquid crystal layer or other suitable dielectric material, and the circuit layer may be manufactured by a thin film process and may selectively include a switching element (such as a thin film transistor (TFT)), so that the bendable electronic device ED may be a bendable antenna, such as a bendable liquid crystal antenna. For example, the electronic layer 190 may include a plurality of antenna units disposed in an active region. The antenna unit may transmit or receive electromagnetic waves.

[0034] The bendable electronic device ED may have an outer surface OS, and the outer surface OS includes a first surface portion P1 defining a first flat area FL1, a second surface portion P2 defining a second flat area FL2, and a third surface portion P3 defining a bendable area FR. When the bendable electronic device ED is unfolded to an unfolded state (or an unfolded state), the first surface portion P1, the second surface portion P2, and the third surface portion P3 are located on the same horizontal plane (coplanar). When the bendable electronic device ED is bent to a bent state, such as Figure 2As shown, the first surface portion P1 is planar and coplanar with a plane PLN1, the second surface portion P2 is planar and coplanar with a plane PLN2, and the third surface portion P3 is curved and is not coplanar with the above planes. Therefore, when the bendable electronic device ED is in a bent state, the third surface portion P3 can be defined as being located between the plane PLN1 and the plane PLN2. In detail, the first boundary B1 can be defined as a position away from the first surface portion P1, and the second boundary B2 can be defined as a position away from the second surface portion P2. In other words, the bendable area FR can be defined by the area between the first boundary B1 and the second boundary B2. In some embodiments, the bendable area FR can be selectively set.

[0035] According to some embodiments, the electronic layer 190 may be a display layer DL. For convenience of description, when the electronic layer 190 is a display layer DL, the following embodiments will take the bendable electronic device ED as a bendable display device 100 as an example. The display layer DL may be disposed in the display region DR and may include a plurality of display units 300. For example, Figure 4 As shown, the display unit 300 may be an organic light emitting diode (OLED) unit, so the bendable electronic device ED may be a bendable display device 100, and the active area AR may be a display area DR. Figure 1 The display region DR may include a first display region DR1 located in the first flat region FL1, a second display region DR2 located in the second flat region FL2, and a bendable region FR. The bendable region FR connects the first display region DR1 and the second display region DR2. Figure 1 FIG. 1 shows a top view of the bendable display device 100 when it is in an open state and displays an image. The area formed by connecting the outermost sides of the peripheral display units 300 can be defined as a display area DR. For example, the display area DR can be defined by connecting the outer sides of the light-emitting areas of the peripheral display units 300. Figure 1 As shown, the display unit 300 may be disposed in the bendable region FR. Alternatively, in some embodiments, the display unit 300 may not be disposed in the bendable region FR.

[0036] The bendable display device 100 may include a flexible substrate SUB, a display layer DL disposed on the flexible substrate SUB, and a biometric sensing structure BSS (eg, a display layer DL disposed in a first display region DR1, a second display region DR2, and a bendable region FR). Figure 3 and Figure 4 shown, but in Figure 1 and Figure 2The biometric sensing structure BSS may include a capacitive sensing structure, an optical sensing structure, an ultrasonic sensing structure or a combination of the above structures.

[0037] The flexible substrate SUB may be a plastic substrate, for example, a polyimide (PI) substrate, a polycarbonate (PC) substrate or a polyethyleneterephthalate (PET) substrate, but is not limited thereto. The display layer DL may include a plurality of film layers. According to some embodiments, the display layer DL may include a signal line, a thin film transistor, a display unit, an insulating layer and / or a circuit, and may be used to control a display image. The display unit may include any suitable display element, such as a light emitting diode, which may be, for example, an organic light emitting diode, a micro light emitting diode (micro LED), a sub-millimeter light emitting diode (mini LED), a quantum dot light emitting diode (quantum dot light emitting diode, QLED) or a liquid crystal layer. In some embodiments, the chip size of the sub-millimeter light emitting diode may range from 100 micrometers (μm) to 300 micrometers. In some embodiments, the chip size of the micro light emitting diode may range from 1 micrometer to 100 micrometers.

[0038] Figure 4 Detailed structures of the display layer DL and the biometric sensing structure BSS are shown. The display layer DL may include a circuit layer 132 and a light emitting structure 134 disposed on the circuit layer 132. The light emitting structure 134 may include a plurality of display units 300. The circuit layer 132 may include a driving element and / or a switching element to drive the display unit 300. For example, the circuit layer 132 may include a plurality of driving elements (e.g., thin film transistors) electrically connected to the corresponding display unit 300 and driving the corresponding display unit 300. In the following, the driving thin film transistor T1 will be used to represent the thin film transistor used to drive the display unit 300. Each driving thin film transistor T1 may include a source electrode SE1, a drain electrode DE1, a gate electrode G1, and a semiconductor layer SL1, and may be electrically connected to the lower electrode of the corresponding display unit 300. The display unit 300 may be an organic light emitting diode in this embodiment.

[0039] For example, if Figure 4As shown, a display unit 300 may include a first electrode 301 (as a lower electrode electrically connected to a thin film transistor), a second electrode 302 (as an upper electrode), and a light-emitting layer 310 disposed between the first electrode 301 and the second electrode 302. The first electrode 301 may be an anode, and the second electrode 302 may be a cathode, but is not limited thereto. The light-emitting region of each display unit 300 may be defined by a dielectric layer 320, and the dielectric layer 320 may serve as a pixel defining layer (PDL). The light-emitting layer 310 may include one or more film layers having a light-emitting material, and may be an organic material. Different display units 300 may emit light having different colors (e.g., red, green, or blue). For example, the light-emitting layers 310 in different display units 300 may be formed of different materials to emit red light, green light, and blue light. The first electrode 301 and the second electrode 302 may include metal or a transparent conductive material, but is not limited thereto. The metal material of the electrode may include, for example, magnesium, calcium, aluminum, silver, tungsten, copper, nickel, chromium, or an alloy of one or more of the above materials. The transparent conductive material may include, for example, indium tin oxide (ITO), indium zinc oxide (IZO), zinc oxide (zinc oxide), or indium oxide (indium oxide).

[0040] The biometric sensing structure BSS can detect or identify biometric features, such as fingerprints, palm prints, facial features or iris features, but is not limited thereto. For example, the biometric sensing structure BSS in this embodiment can detect fingerprints. Please refer to Figure 4 , the biometric sensing structure BSS of this embodiment is a capacitive sensing structure and is disposed on the display layer DL. In other words, in this embodiment, the display layer DL is disposed between the biometric sensing structure BSS and the flexible substrate SUB. The capacitive biometric sensing structure BSS may include a first conductive layer 102, a second conductive layer 104 disposed on the first conductive layer 102, and a dielectric layer 108 disposed between the first conductive layer 102 and the second conductive layer 104. Another dielectric layer or a protective layer 110 may cover the second conductive layer 104. Please refer to Figure 4 and Figure 6 , Figure 4 Shows Figure 6In the cross-sectional schematic diagram along the cut line 4-4', the first conductive layer 102 includes a plurality of first conductive wires 102L extending along a direction D1 parallel to the surface of the flexible substrate SUB, and the second conductive layer 104 includes a plurality of second conductive wires 104L extending along another direction D2 parallel to the surface of the flexible substrate SUB. The direction D1 and the direction D2 may be different directions and may be perpendicular to each other. The direction D1 may be perpendicular to the bending axis FX, and the direction D2 may be parallel to the bending axis FX. In some embodiments, the first conductive wire 102L and the second conductive wire 104L may be linear shapes (e.g., Figure 6 As shown). In some embodiments, the first wire 102L and the second wire 104L may be non-linear shapes, for example, wave shapes or zigzag shapes, or may include curve shapes. Therefore, multiple first wires 102L and multiple second wires 104L intersect with each other and form multiple sensing units BSU. The biometric sensing structure BSS includes multiple sensing units BSU, wherein the sensing units BSU are formed in the overlapping portion of the first wire 102L and the second wire 104L. In other words, one sensing unit BSU may be defined by the overlapping portion of a first wire 102L and a second wire 104L and the dielectric layer 108 corresponding to the overlapping portion. In this embodiment, the sensing units BSU may be respectively arranged between the two display units 300 and do not cover the light emitting area of ​​the display unit 300.

[0041] Please refer to Figure 3 , the biometric sensing structure BSS has a biometric sensing region BR, and the ratio of the area of ​​the biometric sensing region BR to the area of ​​the flexible substrate SUB (hereinafter referred to as the first ratio) ranges from 0.6 to 1. Since the display area DR is smaller than the flexible substrate SUB, the ratio of the area of ​​the biometric sensing region BR to the area of ​​the display area DR (hereinafter referred to as the second ratio) may be greater than the first ratio, and the second ratio may be greater than 0.6, or even greater than 1. In some embodiments, as Figure 3As shown, the area of ​​the display region DR is smaller than the area of ​​the biometric sensing region BR. The minimum distance d1 between the boundary of the display region DR of the display layer DL and the edge SW1 of the flexible substrate SUB is greater than the minimum distance d2 between the boundary of the biometric sensing structure BSS and the edge SW1 of the flexible substrate SUB. The first display region DR1, the bendable region FR, and the second display region DR2 may all be covered by the biometric sensing region BR. In some embodiments, an optical structure may be provided to reflect or guide the reflected light of the fingerprint located in the area where the biometric sensing structure is not provided to the area where the biometric sensing structure is provided, so that the area of ​​the biometric sensing region BR may be larger than the setting range of the biometric sensing structure BSS, so that the biometric sensing region BR may not partially overlap with the biometric sensing structure BSS. In other words, an optical structure may be provided so that a part of the area where the biometric sensing structure BSS is not provided may also be the biometric sensing region BR, wherein the optical structure may be, for example, a light guide plate, a cover layer 124 with a special optical design, or other suitable optical structures, but is not limited thereto. The above-mentioned range of the first ratio of the area of ​​the biometric sensing region BR to the area of ​​the flexible substrate SUB can be applied to other embodiments or variant embodiments of the present invention, so it is not repeated here. According to the present invention, the biometric sensing region BR occupies a relatively large area of ​​the bendable display device 100, so the function of biometric sensing can be improved. The sensing area is not limited to a small area of ​​the bendable display device 100, so the bendable display device 100 of the present invention can more conveniently perform biometric sensing. The execution of biometric sensing can have various forms. According to some embodiments, at least a portion of the biometric sensing region BR extends into the display region DR. For example, at the edge SW1, a portion of the biometric sensing region BR may protrude from a portion of the display region DR, but at another edge, a portion of the biometric sensing region BR may not protrude from a portion of the display region DR. In other words, at different parts of the bendable display device 100, the distance between the boundary of the display region DR and the edge of the flexible substrate SUB may be greater than, equal to, or less than the distance between the boundary of the biometric sensing structure BSS and the edge of the flexible substrate SUB. Therefore, not the entire display area DR must overlap with the biometric sensing area BR. In some embodiments, the biometric sensing area BR can be divided into zones, and the area of ​​the biometric sensing area BR is the total area of ​​the biometric sensing areas BR in each zone.

[0042] In detail, the method for measuring the area of ​​the biometric sensing region BR may include the following steps. Figure 5As shown, the first step: an object with simulated fingerprint features or fingerprint features can be used to touch the bendable display device 100 several times, so that the bendable display device 100 can have several sensing result patterns. Some of the several sensing result patterns may be correct sensing results, such as sensing result patterns FA, FB, FC, FD, FE, FF, and some of the several sensing result patterns may be failed or incorrect sensing results, such as sensing result patterns Fa, Fb, Fc, Fd. The second step: an identification procedure can be performed to find or confirm the correct sensing result patterns FA, FB, FC, FD, FE, FF. The third step: the maximum area that can be enclosed by the connecting line CNL between the center points CP of the correct sensing result patterns FA, FB, FC, FD, FE, FF can be defined to define the biometric sensing area BR. If the boundary of the biometric sensing area BR defined by the third step is irregular, it is recommended to find at least one correct sensing result pattern in each centimeter to define a center point CP in each centimeter, so as to obtain the connecting line CNL and define a more accurate boundary of the biometric sensing area BR. In other words, the maximum distance between two adjacent center points CP of the correct sensing result patterns FA, FB, FC, FD, FE, and FF in the connection line CNL is less than or equal to one centimeter. Figure 3 , the bendable display device 100 may further include a supporting film SUF disposed in the first display region DR1, the second display region DR2, and the bendable region FR. The supporting film SUF may be attached to (or adhered to) the flexible substrate SUB and disposed opposite to the display layer DL. The supporting film SUF may include one or more recessed portions 106 in the bendable region FR. The design of the recessed portion 106 of the supporting film SUF may improve the bending performance of the bendable display device 100. In this embodiment, the ratio of the area of ​​the biometric sensing region BR to the total area of ​​the supporting film SUF ranges from 1 to 1.5. The above area ratio may affect the sensing accuracy of the biometric sensing structure BSS. The supporting film SUF having an area in the above range may provide a good supporting function for the biometric sensing structure BSS. If the area of ​​the supporting film SUF is too small, it may not provide sufficient support, which may increase the sensing error rate of the biometric sensing structure BSS.

[0043] Please refer to Figure 6, as described above, a sensing unit BSU is formed in the overlapping portion of one of the first conductive lines 102L and one of the second conductive lines 104L. In the present embodiment, the interval S1 between two adjacent sensing units BSU among the plurality of sensing units BSU in the first display area DR1 or the second display area DR2 is smaller than the interval S2 between two adjacent sensing units BSU among the plurality of sensing units BSU in the bendable area FR. In other words, the distribution density of the sensing units BSU in the first display area DR1 or the second display area DR2 is greater than the distribution density of the sensing units BSU in the bendable area FR. The distribution density means the number of units (e.g., sensing units) within a given area. Specifically, within a given area, the number of sensing units BSU in the first display area DR1 or the second display area DR2 is greater than the number of sensing units BSU in the bendable area FR. Specifically, according to the present embodiment, the distance between two adjacent second conductive lines 104L in the first display area DR1 and the second display area DR2 is smaller than the distance between two adjacent second conductive lines 104L in the bendable area FR, such as Figure 6 As shown, the interval between two adjacent sensing units BSU in the bendable region FR is larger. In some embodiments, the distance between two adjacent first conductive lines 102L in the first display region DR1 and the second display region DR2 is smaller than the distance between two adjacent first conductive lines 102L in the bendable region FR. In some embodiments, the distance between two adjacent first conductive lines 102L and the distance between two adjacent second conductive lines 104L in the bendable region FR are both greater than the distance between two adjacent first conductive lines 102L and the distance between two adjacent second conductive lines 104L in the first display region DR1 and the second display region DR2. In addition, the height or thickness of the conductive layer (first conductive layer 102, second conductive layer 104) in the first display region DR1 and the second display region DR2 may be greater than the height or thickness of the conductive layer in the bendable region FR. Taking the first conductive layer 102 as an example, the height H1 of the first conductive layer 102 (first conductive line 102L) disposed in the first display region DR1 is greater than the height H2 of the first conductive layer 102 (first conductive line 102L) disposed in the bendable region FR, as shown in FIG. Figure 6The lower half shows a partially enlarged cross-sectional schematic diagram of the first conductive layer 102, wherein, in order to simplify the diagram, the film layer between the flexible substrate SUB and the first conductive layer 102 is omitted here. For example, the first conductive layer 102 may include a first layer 1021, a second layer 1022, and a third layer 1023 to form a composite stacked film layer, wherein the three-layer structure may include molybdenum / aluminum / molybdenum (Mo / Al / Mo) or titanium / aluminum / titanium (Ti / Al / Ti) materials, but is not limited thereto. In some embodiments, the first conductive line 102L and / or the second conductive line 104L may include a plurality of openings, respectively. When the first conductive line 102L includes a plurality of film layers, the opening 102r may pass through all the film layers, or may pass through the top one or two film layers and expose at least one film layer below. Taking one of the first conductive lines 102L in the bendable region FR as an example, it has a plurality of openings 102r passing through the top one or two film layers (third layer 1023, second layer 1022) to expose the lower first layer 1021. In detail, the openings 102r can be formed in the second layer 1022 and the third layer 1023 of the first conductive layer 102. When the bendable display device 100 is in a bent state, the openings 102r can improve the distribution of bending stress or release the stress generated by bending, thereby reducing the probability of damage to the first conductive layer 102 in a bent state or being bent. Figure 6 As shown, for the same first conductive line 102L, the opening 102r may be formed in the bendable region FR, but the portion of the first conductive line 102L located in the first display region DR1 may not include an opening. In some embodiments, the first conductive line 102L may include an opening in the first display region DR1 and / or the second display region DR2 as in the bendable region FR, but the opening of the first conductive line 102L in the first display region DR1 and / or the second display region DR2 may be smaller than the opening of the first conductive line 102L in the bendable region FR. In some embodiments, the distribution density of the openings of the first conductive line 102L in the first display region DR1 and / or the second display region DR2 may be smaller than the distribution density of the openings of the first conductive line 102L in the bendable region FR.

[0044] In some embodiments, the conductive line may further include a curved edge and / or a curved opening. For example, the second conductive line 104L disposed in the bendable region FR may include a plurality of curved openings 104r, such as Figure 6The partially enlarged top view schematic diagram of the second wire 104L on the right is shown. When the bendable display device 100 is in a bent state, the opening 104r can provide a function of releasing bending stress. The opening 104r may include a curved shape and may be an elliptical shape. Similar to the first wire 102L described above, when the second wire 104L includes multiple film layers, the opening 104r may pass through all the film layers, or may pass through the top one or two film layers to expose at least one film layer below. In addition, an opening 104r and the second wire 104L may have a first distance w1 and a second distance w2 between two adjacent outer edges on the same straight line (e.g., a dotted line 500 along the direction D1), and the opening 104r has a third distance w3 on the same dotted line 500. In some embodiments, the relationship between the first distance w1, the second distance w2, and the third distance w3 satisfies at least one of the following formulas:

[0045] w3≤(w1+w2)

[0046] 0.2≤(w2-w1) / (w1+w2)≤0.6

[0047] w1≠w2

[0048] The electronic device and the bendable display device of the present invention are not limited to the aforementioned embodiments, and may have other different embodiments and variant embodiments. In order to simplify the description, the following embodiments will use the same symbols to mark the same elements. In order to facilitate the comparison of the differences between the embodiments, the differences between the different embodiments will be described in detail below, and the same technical features will not be repeated.

[0049] Please refer to Figure 7 and Figure 8 , Figure 7 is a schematic top view of an electronic device according to a second embodiment of the present invention, Figure 8 for Figure 7 The schematic cross-sectional view of the electronic device shown is along the cut line 8-8'. The main difference between this embodiment and the previous embodiment is that Figure 7 and Figure 8The electronic device ED in the embodiment has a curved surface. In detail, the flexible substrate SUB may have a curved portion CR1 and a curved portion CR2 outside the first flat area FL1 and the second flat area FL2, respectively. The curved portion CR1 and the curved portion CR2 are located near the edge of the flexible substrate SUB. The electronic device ED is bent along the bending axis BX1 to form the curved portion CR1, and is bent along the bending axis BX2 to form the curved portion CR2. According to the present embodiment, the biometric sensing structure BSS (or the biometric sensing area BR) covers at least a portion of the curved portion CR1 and at least a portion of the curved portion CR2. In addition, in the present embodiment, the area of ​​the display layer DL may be smaller than the area of ​​the biometric sensing structure BSS (or the area of ​​the biometric sensing area BR), and the area of ​​the biometric sensing structure BSS may be smaller than the area of ​​the flexible substrate SUB. However, in some other embodiments, the area of ​​the display layer DL (which may refer to the display area) and the area of ​​the biometric sensing structure BSS may be roughly the same as the area of ​​the flexible substrate SUB. In some other embodiments, the area of ​​the display layer DL may be larger than the area of ​​the biometric sensing structure BSS. Furthermore, in the present embodiment, the bendable display device 100 has a first support film SUF1 disposed in the first display region DR1 and a second support film SUF2 disposed in the second display region DR2. The first support film SUF1 and the second support film SUF2 are attached to the flexible substrate SUB and are disposed opposite to the display layer DL. The first support film SUF1 may not be connected to the second support film SUF2, and a recessed portion 106 may be formed between the first support film SUF1 and the second support film SUF2. In some embodiments, some portions of the first support film SUF1 may be connected to the second support film SUF2 in the bendable region FR ( Figure 8 In this embodiment, the first support film SUF1 and the second support film SUF2 may have inclined side walls facing the recessed portion 106, such as Figure 8 Furthermore, according to this embodiment, the ratio of the area of ​​the biometric sensing region of the biometric sensing structure BSS to the sum of the area of ​​the first supporting film SUF1 and the area of ​​the second supporting film SUF2 ranges from 1 to 1.5.

[0050] Please refer to Figures 9 to 11 , Fig. 9 is a cross-sectional schematic diagram of an electronic device according to a third embodiment of the present invention, Fig.10 for Fig. 9 A schematic top view of the electronic device shown in FIG. Fig.11 for Fig.10 The electronic device shown is a cross-sectional schematic diagram with more detailed components and a partially enlarged schematic diagram. Fig.10Only the flexible substrate SUB and the biometric sensing structure BSS are shown. To simplify the diagram, other elements of the bendable display device 100 are omitted. In this embodiment, the interval d3 between two adjacent sensing units BSU in the first display region DR1 or the second display region DR2 along the direction D1 is smaller than the interval d4 between two adjacent sensing units BSU in the bendable region FR along the direction D1, wherein the direction D1 may be perpendicular to the bending axis FX. In other words, the distribution density of the sensing units BSU in the first display region DR1 or the second display region DR2 is greater than the distribution density of the sensing units BSU in the bendable region FR.

[0051] like Fig.11 As shown, the display layer DL may include a circuit layer 132 and a light emitting structure 134 disposed on the circuit layer 132. The circuit layer 132 may include a plurality of switching elements or driving elements (e.g., a driving thin film transistor T1) and a plurality of wires. The light emitting structure 134 may include a plurality of display units 300 electrically connected to corresponding driving elements. The driving thin film transistor T1 as a driving element of a display unit 300 may include a source SE1, a drain DE1, a gate G1, and a semiconductor layer SL1. The biometric sensing structure BSS in this embodiment is an optical sensing structure, and the biometric sensing structure BSS is disposed between the display layer DL and the flexible substrate SUB. In detail, the sensing unit BSU of the biometric sensing structure BSS may be embedded in the display layer DL. In other words, at least a portion of the sensing unit BSU may be formed in the display layer DL. For example, the sensing unit BSU may be formed by a thin film transistor and disposed in the display layer DL. As Fig.11As shown in the enlarged part, the thin film transistor structure (labeled as sensing thin film transistor T2) in a sensing unit BSU may include a gate G2, a source SE2, a drain DE2 and a semiconductor layer SL2. The semiconductor layer SL1, the gate G1, the source SE1 and the drain DE1 of the driving thin film transistor T1 used to drive the display unit 300 and the semiconductor layer SL2, the gate G2, the source SE2 and the drain DE2 of the sensing thin film transistor T2 of the sensing unit BSU may be formed of the same material or film layer. The first insulating layer 1321 may be formed on the semiconductor layer SL2. The gate G2 may be formed on the first insulating layer 1321 and the semiconductor layer SL2. The gate G2 may be formed by the first metal layer M1 in the circuit layer 132. The second insulating layer 1322 may be disposed on the first metal layer M1. The source SE2 and the drain DE2 may be disposed on the second insulating layer 1322 and pass through the second insulating layer 1322 and the first insulating layer 1321 to contact the two ends of the semiconductor layer SL2. The source electrode SE2 and the drain electrode DE2 may be formed by the second metal layer M2 of the circuit layer 132. The flat layer 1323 may be disposed on the second metal layer M2 and the second insulating layer 1322. In order to prevent ambient light from irradiating the semiconductor layers SL1 and SL2, the circuit layer 132 may include light shielding portions LS1 and LS2 located between the semiconductor layer SL1 or SL2 and the flexible substrate SUB. The light shielding portions LS1 and LS2 may be formed by a metal layer, and a third insulating layer 334 may be disposed between the metal layer and the semiconductor layers SL1 and SL2. Light L passing through the inner surface of the bendable display device 100 may be reflected by the light shielding portion LS1 to the semiconductor layer SL2, and the semiconductor layer SL2 may receive an optical signal. In some embodiments, the first metal layer M1 and the second metal layer M2 may include pin holes PH1 and PH2 to allow light L to pass through.

[0052] The light emitting structure 134 may include a plurality of light emitting diodes 336 as the display unit 300, a third metal layer M3, a partition layer PL, and a fourth metal layer M4. The third metal layer M3 may include an electrode E1 passing through the planar layer 1323 to electrically connect one light emitting diode 336 to the corresponding driving thin film transistor T1. The partition layer PL may have a cup-shaped structure to set the corresponding light emitting diode 336. The fourth metal layer M4 may include another electrode E2 on the corresponding light emitting diode 336. In addition, in order to allow light to pass through the third metal layer M3 and the fourth metal layer M4, the third metal layer M3 and the fourth metal layer M4 may further include pinholes PH3 and PH4. In the top-view direction D3, a thin film transistor element (sensing thin film transistor T2) may be made as a sensing unit BSU, and the sensing unit BSU may be set on one side of the light emitting diode 336 in the longitudinal direction D1 to sense the light signal. Therefore, the biometric sensing area of ​​the biometric sensing structure BSS can be defined by the connecting lines of the outer edges of the outermost sensing units BSU, that is, it can be defined by the connecting lines of the outer edges of the outermost sensing thin film transistors T2. Therefore, the area of ​​the biometric sensing area can be defined as the area within the area surrounded by the connecting lines of the outer edges of the outermost sensing thin film transistors T2. On the other hand, the display area of ​​the display layer DL can be defined by connecting the outer edges of the outermost light-emitting diodes 336. The structure of the display layer DL and the biometric sensing structure BSS is not limited to the above. In another embodiment, the optical biometric sensing structure BSS can be arranged between the support film SUF and the flexible substrate SUB.

[0053] Please refer to Fig.11 In this embodiment, the protective layer 120 can cover the display layer DL and the biometric sensing structure BSS. An over-coating adhesive 122 can be coated on the protective layer 120 to attach a cover layer 124 to the protective layer 120. Fig.11 In addition, the bendable display device 100 may further include a flexible circuit board 224 to electrically connect the biometric sensing structure BSS to the control unit 212, wherein the flexible circuit board 224 may be a flexible printed circuit (FPC), and the control unit 212 may be an integrated circuit (IC) package, but is not limited thereto.

[0054] Please refer to Fig.12 , Fig.12Schematic diagram of a top view of an electronic device of a first variation of the third embodiment of the present invention. The difference between this embodiment and the third embodiment is that the area of ​​the sensing unit BSU disposed in the first display area DR1 and the second display area DR2 of this embodiment is different from the area of ​​the sensing unit BSU disposed in the bendable area FR. In detail, the width W1 of one of the sensing units BSU disposed in the first display area DR1 or the second display area DR2 in the direction D1 may be greater than the width W2 of one of the sensing units BSU disposed in the bendable area FR in the direction D1. Therefore, the area of ​​one sensing unit BSU disposed in the first display area DR1 or the second display area DR2 may be greater than the area of ​​one sensing unit BSU disposed in the bendable area FR.

[0055] Please refer to Fig.13 , Fig.13 It is a partially enlarged cross-sectional schematic diagram of an electronic device according to a second variation of the third embodiment of the present invention. Fig.13 Another sensing unit BSU of an optical sensor is shown. The sensing unit BSU includes a sensing thin film transistor T2 and a group of diode layers, such as a PIN layer 136. The PIN layer 136 includes an N+ type semiconductor layer, an intrinsic semiconductor layer, and a P type semiconductor layer stacked in sequence (e.g., stacked from bottom to top). The lower electrode 138 disposed under the PIN layer 136 can be electrically connected to the source SE2 of the sensing thin film transistor T2, and the upper electrode 140 can be disposed on the PIN layer 136. When light enters the PIN layer 136, the PIN layer 136 can generate current and transmit a signal through the thin film transistor element electrically connected thereto.

[0056] Please refer to Fig.14 , Fig.14 FIG. 4 is a cross-sectional view of an electronic device according to a fourth embodiment of the present invention. The biometric sensing structure of this embodiment is a hybrid-type sensing structure, which may include two or more of an ultrasonic sensing structure, a capacitive sensing structure, and an optical sensing structure. Fig.14As shown, the biometric sensing structure includes a first biometric sensing structure BSS1 disposed in the bendable region FR, a second biometric sensing structure BSS2 disposed in the first display region DR1, and a third biometric sensing structure BSS3 disposed in the second display region DR2. The structure or type of the first biometric sensing structure BSS1 may be different from the structure or type of the second biometric sensing structure BSS2 and the third biometric sensing structure BSS3. The first biometric sensing structure BSS1 is disposed between the display layer DL and the flexible substrate SUB, and may include an optical sensor or a capacitive sensor, but is not limited thereto. The second biometric sensing structure BSS2 and the third biometric sensing structure BSS3 are disposed between the flexible substrate SUB and the supporting film SUF, and may include an optical sensor or an ultrasonic sensor, but is not limited thereto.

[0057] Please refer to Fig.15 , Fig.15 FIG. 5 is a schematic top view of an electronic device along a direction D3 according to a fifth embodiment of the present invention. The sensing units of the biometric sensing structure BSS may be arranged in a variety of ways. Fig.15 The bottom of the figure shows partial enlarged schematic diagrams of regions r1, r2, and r3 of the first display region DR1, the second display region DR2, and the bendable region FR, respectively. The display units 351, 352, and 353 may represent three display units for generating light of different colors (e.g., blue light, red light, and green light), but are not limited thereto. In region r1, three display units 351, 352, and 353 are arranged side by side along the direction D1, two sensing units BSU1 are arranged side by side along the direction D2, and the sensing units BSU1 are all arranged on the same side of the display unit 353. That is, in the first display region DR1, the three display units are combined with the two sensing units as a repeating unit and are repeatedly arranged in the first display region DR1. Region r2 shows a similar arrangement. However, in region r3, only one sensing unit BSU3 is arranged on one side of the display unit 353 in the direction D1. That is, in the bendable region FR, the three display units are combined with one sensing unit as a repeating unit to be repeatedly arranged in the bendable region FR. Therefore, the distribution density of the sensing units in the bendable region FR is less than the distribution density of the sensing units in the first display region DR1 and / or the second display region DR2. In some embodiments, although not shown in the figure, the sensing unit BSU1 in the region r1 or the sensing unit BSU2 in the region r2 may be arranged on one side of the three display units 351, 352, 353 in the direction D2, and the sensing unit BSU3 in the region r3 may be arranged on one side of the three display units 351, 352, 353 in the direction D1. The arrangement of the display units 351, 352, 353 and the sensing units BSU1, BSU2, BSU3 is not limited to the above content.

[0058] Please refer to Fig.16 , Fig.16 Schematic cross-sectional view of an electronic device according to a sixth embodiment of the present invention. The electronic device ED is a bendable double-sided display device that can display images on opposite sides. The electronic device ED includes a flexible substrate SUB having a first side 61 and a second side 62 relative to the first side 61. In addition, a first display layer DL1 and a first biometric sensing structure BSS1 are disposed on the first side 61, and a second display layer DL2 and a second biometric sensing structure BSS2 are disposed on the second side 62. According to some embodiments, the first display layer DL1 may be disposed between the flexible substrate SUB and the first biometric sensing structure BSS1, and the second display layer DL2 may be disposed between the flexible substrate SUB and the second biometric sensing structure BSS2. In order to improve the bending performance of the electronic device ED and reduce the probability of damage to components in the bendable region FR, the electronic device ED may have a recess 150 in the bendable region FR. Specifically, compared with the first display region DR1, the flexible substrate SUB of the bendable region FR may have a reduced thickness. Therefore, the total thickness of the flexible substrate SUB, the first display layer DL1, the second display layer DL2, the first biometric sensing structure BSS1, and the second biometric sensing structure BSS2 in the bendable region FR can be reduced to form a recess 150 in the bendable region FR, wherein the recess 150 can be located on one side or both sides of the bendable display device 100. In the present embodiment, the first display layer DL1 and the second display layer DL2 can have the same area as the first biometric sensing structure BSS1 or the second biometric sensing structure BSS2, but is not limited thereto.

[0059] Please refer to Fig.17 , Fig.17 FIG. 1 is a flow chart of an operation method of an electronic device according to a seventh embodiment of the present invention. The operation method of the electronic device comprises the following steps:

[0060] Step 102: Provide an electronic device in a standby state, wherein the electronic device includes a bendable display device, the bendable display device includes a flexible substrate, a display layer disposed on the flexible substrate, and a biometric sensing structure disposed on the flexible substrate.

[0061] Step 104: When the flexible display device is provided with a touch signal (eg, generated by a user's touch), a detection procedure is executed to confirm whether the touch signal meets a predetermined condition; and

[0062] Step 106: When the touch signal meets the predetermined condition, the biometric sensing mode is turned on. In other words, if the confirmation result of step 104 is "yes", the biometric sensing mode is turned on, but if the confirmation result of step 104 is "no", the biometric sensing mode is not turned on, and the electronic device remains in the standby state and does not execute the biometric sensing procedure.

[0063] According to the present invention, the ratio of the area of ​​the biometric sensing region of the biometric sensing structure to the area of ​​the flexible substrate (i.e., the aforementioned "first ratio") ranges from 0.6 to 1. In some embodiments, the predetermined condition may be related to the touch duration of the touch signal, for example, the predetermined condition may be a touch duration greater than or equal to 0.3 seconds and less than or equal to 3 seconds, and when the duration of the touch signal (e.g., provided by the user) falls within the above range, the biometric detection mode is turned on. In some embodiments, the predetermined condition may be related to the touch area, for example, the predetermined condition may be greater than 50 mm 2 The touch area is greater than 50mm when the user provides the touch area. 2 In some other embodiments, the predetermined condition may be related to the operating state of a specific application stored in the electronic device. If the specific application stored in the electronic device is turned on, it means that the predetermined condition is met, and the biometric detection mode will be turned on.

[0064] According to the present invention, in a bendable display device, the biometric sensing structure occupies a larger proportion (0.6 to 1) of the area of ​​the flexible substrate. The biometric sensing structure can be arranged in the first display area, the second display area and the bendable area, so that the performance of biometric sensing can be improved.

[0065] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A bendable display device, characterized in that: The bendable display device comprises a first display area, a second display area and a bendable area connecting the first display area and the second display area, wherein the bendable display device comprises: a supporting film; a flexible substrate disposed on the support film; a display layer disposed on the flexible substrate, the display layer comprising a display unit and a metal layer, the metal layer comprising an opening for light to pass through; a control unit, disposed under the supporting film; and A biometric identification sensing structure is electrically connected to the control unit, the biometric identification sensing structure includes a plurality of sensing units, and the biometric identification sensing structure includes: a first conductive layer, comprising a plurality of first conductive lines extending along a first direction; and a second conductive layer, comprising a plurality of second conductive lines extending along a second direction not parallel to the first direction, wherein the plurality of first conductive lines intersect with the plurality of second conductive lines to form the plurality of sensing units; wherein the biometric sensing structure is used to detect fingerprints, and the supporting film includes a concave portion in the bendable region; wherein the ratio of the area of ​​the biometric sensing structure to the area of ​​the flexible substrate ranges from 0.6 to 1; The distance between two adjacent ones of the plurality of first conductive lines located in the bendable area is greater than the distance between another two adjacent ones of the plurality of first conductive lines located in the first display area or the second display area.

2. The bendable display device according to claim 1, characterized in that: It also includes a flexible circuit board, and the biometric identification sensing structure is electrically connected to the control unit through the flexible circuit board.

3. The bendable display device according to claim 2, characterized in that: The flexible circuit board and the control unit do not overlap in the bendable area.

4. The bendable display device according to claim 1, characterized in that: The flexible substrate includes a curved portion.

Images