Display device

Abstract

A display device is provided. The display device includes: a display panel including a pad area; a flexible printed circuit board connected to the display panel; and a buffer layer disposed between the display panel and the flexible printed circuit board. The flexible printed circuit board includes: a main body portion on which a component is disposed; a pressing portion disposed along an edge of the main body portion and coupled to the pad region; and a tail portion extending from the main body portion, the tail portion overlapping the buffer layer.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims priority to and the benefit of Korean Patent Application No. 10-2023-0159084, filed in the Korean Intellectual Property Office on November 16, 2023, the entire contents of which are incorporated herein by reference. Technical Field

[0003] The present disclosure relates to a display device, and more particularly, to a display device including a display panel displaying an image and a flexible printed circuit board connected to the display panel. Background Art

[0004] The display device includes pixels and displays an image on a display screen by controlling the brightness of each pixel. The display device may include a touch sensing unit capable of detecting a user's touch. The display device may include a display panel on which pixels are formed. The touch sensor may be provided on the display panel. For example, the display panel may include a touch sensor, or a panel including a touch sensor may be attached to the display panel. Summary of the invention

[0005] The display device may include a flexible printed circuit board connected to the display panel and transmitting a signal to the display panel. For example, the display panel may receive a signal for driving a pixel and a signal for driving a touch sensor through the flexible printed circuit board.

[0006] In an electronic device to which the display device is applied, the flexible printed circuit board can be bent to prevent interference with other components (e.g., a battery). The thickness of the bent portion of the flexible printed circuit board increases so that it can press the adhesive layer attaching the display panel and the cover window, and the pressed portion of the adhesive layer can be visible through the cover window.

[0007] Embodiments provide a display device that can relieve pressure on an adhesive layer through a bent portion of a flexible printed circuit board.

[0008] A display device according to an embodiment includes: a display panel including a pad area; a flexible printed circuit board connected to the display panel; and a buffer layer arranged between the display panel and the flexible printed circuit board. The flexible printed circuit board includes: a main body portion on which a component is disposed; a connecting portion arranged along a first edge of the main body portion and coupled to the pad area; and a tail portion extending from a second edge of the main body portion opposite to the first edge, and the tail portion vertically overlaps the buffer layer.

[0009] The tail portion may include a bent portion, and the bent portion may vertically overlap the buffer layer.

[0010] The connection portion may extend in a first direction parallel to the shorter side of the display panel, and the tail portion may include: a first portion extending from a second edge of the main portion in a second direction parallel to the longer side of the display panel and intersecting the first direction; and a second portion extending from the first portion in the first direction. The first portion may be bent around an axis parallel to the first direction.

[0011] At least a portion of the second portion may overlap the main body portion.

[0012] The width of the buffer layer may be equal to or greater than the width of the tail portion.

[0013] The buffer layer may be made of stainless steel.

[0014] A buffer layer may be attached to the back side of the display panel.

[0015] A buffer layer may be attached to the tail.

[0016] The buffer layer may be attached to the tail using an adhesive layer. The adhesive layer may be arranged between a portion of the buffer layer and the tail. The portion of the buffer layer may be attached to the tail using an adhesive layer. The portion of the buffer layer may correspond to two-thirds or less of the planar area of ​​the buffer layer.

[0017] The display device may further include: a cover window overlapping the display panel; and an adhesive layer disposed between the display panel and the cover window.

[0018] A display device according to an embodiment includes: a display panel including a main area including a display area and a touch area, a sub-area extending from the main area and in which a display driver is located, wherein the main area has a first side extending in a first direction and a second side extending in a second direction, wherein the second side is longer than the first side, and the first direction intersects with the second direction; a flexible printed circuit board connected to the sub-area; and a buffer layer arranged between the main area and the flexible printed circuit board. The flexible printed circuit board includes: a main body in which a touch driver is positioned; a connecting part arranged along a first edge of the main body and coupled to the sub-area; and a tail extending from a second edge of the main body opposite to the first edge and having a thickness thinner than the main body. The tail includes: a first portion extending from the main body and overlapping the buffer layer; and a second portion extending from the first portion.

[0019] The first portion may include a bent portion, and the bent portion may overlap the buffer layer.

[0020] The second portion may extend in a first direction, and the first portion may extend in the second direction and may be bent about an axis parallel to the first direction.

[0021] At least a portion of the second portion may vertically overlap the main body portion.

[0022] The buffer layer may have a width greater than a width of the first portion.

[0023] The buffer layer may have a thickness of about 0.2 mm or less.

[0024] A buffer layer may be attached to the back side of the primary region.

[0025] A buffer layer may be attached to the first portion.

[0026] The display device may further include: an adhesive layer disposed between a portion of the buffer layer and the tail portion. The buffer layer may be attached to the first portion. The portion of the buffer layer may be attached to the tail portion using the adhesive layer. The portion of the buffer layer may correspond to two-thirds or less of the planar area of ​​the buffer layer.

[0027] The display device may further include: a cover window overlapping the display panel; and an adhesive layer disposed between the display panel and the cover window.

[0028] According to the embodiment, it is possible to provide a display device that can relieve pressure on an adhesive layer through a bent portion of a flexible circuit board and prevent a pressed portion of the adhesive layer from being recognized. In addition, according to the embodiment, there are advantageous effects that can be recognized throughout the specification. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 is a perspective view of an electronic device according to an embodiment of the present disclosure.

[0030] Figure 2 is a perspective view of a display device included in an electronic device according to an embodiment of the present disclosure.

[0031] Figure 3 is a plan view showing a connection relationship between a plurality of components of a display device according to an embodiment of the present disclosure.

[0032] Figure 4 is a rear view of a display device according to an embodiment of the present disclosure.

[0033] Figure 5 According to the embodiment of the present disclosure Figure 4 A cross-sectional view taken along line AA' in FIG.

[0034] Figure 6 According to the embodiment of the present disclosure Figure 4 A cross-sectional view taken along line BB' in FIG.

[0035] Figure 7 is a rear view of a display device according to an embodiment of the present disclosure.

[0036] Figure 8 According to the embodiment of the present disclosure Figure 7 A cross-sectional view taken along line CC'.

[0037] Fig. 9 is a cross-sectional view of a display device according to a comparative example.

[0038] Fig.10 and Fig.11 is a schematic cross-sectional view of a display device according to an embodiment of the present disclosure.

[0039] Fig.12 is a schematic cross-sectional view of a display panel according to an embodiment of the present disclosure. DETAILED DESCRIPTION

[0040] With reference to the accompanying drawings, the embodiments will be described in detail so that those skilled in the art can easily implement the embodiments.

[0041] When a component of a layer, film, region or plate is referred to as being "on" or "over" another component, this includes not only being "directly on" another component but also having other components therebetween. Conversely, when a component is referred to as being "directly over" another component, this means that no other components are present therebetween.

[0042] Throughout the specification, a component may further include other elements unless there is a statement to the contrary: a component “includes” a certain element.

[0043] Throughout the specification, “connected” means not only when two or more components are directly connected, but also when two or more components are indirectly connected through other components, when two or more components are physically connected, or when two or more components are electrically connected. In addition to these cases, “connected” may also include a case in which each component (referred to by different names according to position or function, but substantially integrated) is connected to another component.

[0044] In the drawings, symbols “DR1”, “DR2” and “DR3” are used to indicate directions, where “DR1” is a first direction, “DR2” is a second direction perpendicular to the first direction, and “DR3” is a third direction perpendicular to the first and second directions.

[0045] Figure 1 is a perspective view of an electronic device according to an embodiment of the present disclosure, and Figure 2is a perspective view of a display device included in an electronic device according to an embodiment of the present disclosure.

[0046] refer to Figure 1 and Figure 2 , the electronic device 1 may include a display screen capable of displaying an image in a third direction DR3. The display screen may correspond to the front of the electronic device 1 in a plane defined by the first direction DR1 and the second direction DR2. The electronic device 1 may be a device whose main function is to display an image. The electronic device 1 may be a smart phone, a mobile phone, a tablet computer, a multimedia player, a game console, or a monitor. The electronic device 1 may include at least one of a cover window 10, a housing 20, and a display device 30.

[0047] The cover window 10 may include an insulating panel. For example, the cover window 10 may be made of glass, plastic, or a combination thereof. The front of the cover window 10 may define the front of the electronic device 1. The area of ​​the cover window 10 corresponding to the display screen may be optically transparent. The cover window 10 is located above the display device 30 to protect the display device 30 from external impacts, etc., and transmit the image displayed by the display device 30. The cover window 10 may also be considered as a component of the display device 30.

[0048] The housing 20 may be made of a material having relatively high rigidity. For example, the housing 20 may include a plurality of frames and / or plates made of glass, plastic, metal, or a combination thereof. The housing 20 may be combined with the cover window 10. The combined structure of the housing 20 and the cover window 10 may constitute the appearance of the electronic device 1 and provide an internal space for the electronic device 1. For example, the housing 20 may form the back and sides of the electronic device 1, and the cover window 10 may form the front of the electronic device 1. The display device 30 may be located in the internal space defined by the cover window 10 and the housing 20 that protect the display device 30 from the external environment.

[0049] The display device 30 can display images and provide a display screen of the electronic device 1. The display device 30 may be a light-emitting display device such as an organic light-emitting display device, an inorganic light-emitting display device, and a quantum dot light-emitting display device.

[0050] The electronic device 1 may have various shapes. For example, when viewed from the front, the electronic device 1 may have a rectangular shape with rounded corners, such as Figure 1 In the implementation, the electronic device 1 may have a shape such as a rectangle, a square, other polygons, a circle, and an ellipse.

[0051] Each of the electronic device 1 and the display device 30 may include a display area DA and a non-display area NA. Figure 1The display area DA and the non-display area NA of the electronic device 1 shown in FIG. Figure 2 The display area DA of the display device 30 shown in FIG. 3 corresponds to the non-display area NA. The display area DA is an area in which an image is displayed, and may correspond to a display screen. The non-display area NA is an area in which an image is not displayed. For example, the front of the electronic device 1 may be divided into the display area DA and the non-display area NA.

[0052] The display area DA may occupy most of the front of the electronic device 1, and the non-display area NA may surround the display area DA. In an embodiment, the non-display area NA may completely or partially surround the display area DA. The display area DA may include a first display area DA1, a second display area DA2, and a third display area DA3. The second display area DA2 and the third display area DA3 may be areas where components such as sensors and cameras for adding various functions to the electronic device 1 are placed on the rear side. The second display area DA2 and the third display area DA3 may correspond to the component area. The second display area DA2 and the third display area DA3 may be surrounded by the first display area DA1. In addition to the first display area DA1, the second display area DA2 and the third display area DA3 may also display images. The position and number of the second display area DA2 and the third display area DA3 may be changed in various ways. The first direction DR1 is parallel to the shorter side of the first display area DA1, and the second direction DR2 is parallel to the longer side of the first display area DA1.

[0053] To describe the display device 30 in more detail, the display device 30 may provide a display screen in the electronic device 1. The planar shape of the display device 30 may be similar to that of the electronic device 1.

[0054] The display device 30 may include a display panel 100, a display driver 200, a flexible printed circuit board 300, and a touch driver 400. The display device 30 may further include a cover window 10. The display panel 100 may be attached to the cover window 10 through an adhesive layer. The display panel 100 may include a main area MA and a sub-area SA.

[0055] The main area MA may include a display area DA in which pixels displaying an image are arranged and a non-display area NA around the display area DA. The display area DA may include a first display area DA1, a second display area DA2, and a third display area DA3. Components such as sensors and cameras may be placed on the back of the second display area DA2 and the third display area DA3, and the second display area DA2 and the third display area DA3 correspond to the component area. The display area DA may emit light from a light-emitting area corresponding to the light-emitting element in a third direction DR3. For example, the display panel 100 may include a pixel circuit portion including a transistor, a signal line (e.g., a gate line, a data line, and a voltage line) connected to the pixel circuit portion, and a light-emitting element connected to the pixel circuit portion.

[0056] The display panel 100 may include a pixel defining layer having an opening defining a light emitting area of ​​each light emitting element. The light emitting element may include an organic light emitting diode including an organic light emitting layer, a quantum dot light emitting diode including a quantum dot light emitting layer, an inorganic light emitting diode including an inorganic semiconductor, and / or a micro light emitting diode. The non-display area NA may surround the display area DA.

[0057] The non-display area NA may be defined as an edge area of ​​the main area MA of the display panel 100. Circuits and / or signal lines for generating and / or transmitting various signals applied to the display area DA may be arranged in the non-display area NA. For example, the non-display area NA may include a gate driver that supplies gate signals to gate lines (see Figure 3 The display driver 200 may include a gate driver 210 in the display area DA and a fan-out line that connects the display driver 200 to a signal line (not shown) in the display area DA.

[0058] The sub-region SA may be a region extending from one side of the main region MA in a direction away from the main region MA. The sub-region SA may include a flexible region that can be bent, folded, curled, etc. For example, the sub-region SA may be bent to overlap with the main region MA in the thickness direction (third direction DR3). The display driver 200 may be located in the sub-region SA, and the pad region of the display panel 100 may be located at an edge of the sub-region SA. In an embodiment, the pad region of the display panel 100 may be adjacent to an edge of the sub-region SA. Figure 3 The configuration of the pad area is described in detail. The flexible printed circuit board 300 may be connected to the pad area of ​​the display panel 100. In an embodiment, the sub-area SA may be omitted, and the display driver 200 and the pad area may be placed in the non-display area NA.

[0059] The display driver 200 may output a signal and a voltage for driving the display panel 100. The display driver 200 may supply a data voltage to a data line. The display driver 200 may supply a power voltage to a power line and supply a gate control signal to a gate driver. The display driver 200 may be provided as an integrated circuit chip and may be mounted on the display panel 100. For example, the display driver 200 may be arranged in a sub-region SA and may overlap with the main region MA in a thickness direction (third direction DR3) by bending the sub-region SA. In an embodiment, the display driver 200 may be mounted on a flexible printed circuit board 300.

[0060] The flexible printed circuit board 300 may include a body portion 310 , a pressing portion 320 (ie, a connecting portion), a tail portion 330 , and a connecting terminal 340 .

[0061] The main body 310 may occupy the largest area of ​​the flexible printed circuit board 300 and may be multi-layered. For example, the main body 310 may include four or more conductive layers stacked on each other. Components such as the touch driver 400, capacitors, resistors, and inductors may be arranged on the main body 310.

[0062] The pressing portion 320 may be located along an edge of the body portion 310. The pressing portion 320 may extend in a first direction DR1 extending along a shorter side of the first display area DA1.

[0063] The extrusion portion 320 may be bonded to the pad region of the display panel 100 using an electrical and physical bonding method such as an anisotropic conductive film. The pad located in the extrusion portion 320 of the flexible printed circuit board 300 may be electrically connected to the pad located in the pad region of the display panel 100. The extrusion portion 320 may include one or more conductive layers. The number of conductive layers included in the extrusion portion 320 may be less than the number of conductive layers included in the body portion 310. For example, the extrusion portion 320 may include one or two layers as conductive layers, and the body portion 310 may include four or more layers as conductive layers.

[0064] The tail portion 330 may extend from the main body portion 310 in a direction away from the main body portion 310, and the connection terminal 340 may be formed at the end of the tail portion 330. The tail portion 330 may be bent once or multiple times in a plane. In an embodiment, the tail portion 330 may have a planar shape such as an "L" shape. For example, the tail portion 330 may include a first portion 331 connected to the main body portion 310 and a second portion 332 connected to the first portion 331. The first portion 331 may extend from the main body portion 310 along the second direction DR2 in a direction away from the main body portion 310. The second portion 332 may extend from the first portion 331 along the first direction DR1. In an embodiment, the tail portion 330 may be straight in a plane. The tail portion 330 may be bent so that at least a portion of the tail portion 330 overlaps with the main body portion 310. At least a portion of the tail portion 330 may be attached to the main body portion 310. The number of conductive layers included in the tail portion 330 may be less than the number of conductive layers included in the main body portion 310. For example, the tail portion 330 may include one or two layers as a conductive layer, and the main body portion 310 may include four or more conductive layers. In an embodiment, the extrusion portion 320 may be arranged along a first edge of the main body portion 310 and bonded to the pad area, which will be referred to as Figure 3 The tail portion 330 may extend from a second edge of the body portion 310 opposite to the first edge.

[0065] The connection terminal 340 may be located at the edge of the tail 330. The connection terminal 340 may include a connection terminal connected to the wiring of the tail 330. The connection terminal 340 is connected to an external device such as a graphics system and a power system to receive digital video data and power. The mobile industry processor interface (MIPI) can be used for high-speed transmission of digital video data. The signal and power applied by the connection terminal 340 can be sent to the wiring provided in the main body 310 through the wiring provided in the tail 330.

[0066] The touch driver 400 may be provided as an integrated circuit chip and may be mounted on the flexible printed circuit board 300. The touch driver 400 may be electrically connected to a touch sensor included in the electronic device 1. The touch sensor may be provided in the display area DA of the display panel 100. The touch driver 400 may supply an input signal (touch drive signal) to the detection electrode of the touch sensing unit, and may detect the amount of change in capacitance between the sensing electrodes based on an output signal (touch sensing signal) from the sensing electrode. For example, the touch drive signal may be a pulse signal having a predetermined frequency. The touch driver 400 may calculate whether a touch is performed and the touch coordinates based on the amount of change in capacitance between the sensing electrodes.

[0067] Figure 3is a plan view showing a connection relationship between a plurality of components of a display device according to an embodiment of the present disclosure.

[0068] refer to Figure 3 , the display panel 100 of the display device 30 may include a display area DA and a non-display area NA. The display area DA may be located in the middle of the display panel 100. Unit pixels (equivalent to pixels) PX, gate lines GL, data lines DL, and power lines VL may be arranged in the display area DA. Each unit pixel PX is the smallest unit that emits light, and may include a pixel circuit portion including a transistor and a capacitor, and a light-emitting element that receives a driving current from the pixel circuit portion. The unit pixel PX may be connected to the gate line GL, the data line DL, and the power line VL. The unit pixel PX may be repeatedly arranged in the display area DA.

[0069] The gate line GL may supply a gate signal applied from the gate driver 210 to the unit pixel PX. A plurality of gate lines GL may extend in the first direction DR1 and may be spaced apart from each other in the second direction DR2. The data line DL may supply a data voltage applied from the display driver 200 to the unit pixel PX. A plurality of data lines DL may extend in the second direction DR2 and may be spaced apart from each other in the first direction DR1. The power line VL may supply a power voltage applied from the display driver 200 to the unit pixel PX. The power voltage may include a high potential power voltage (or driving voltage), a low potential power voltage (or common voltage), an initialization voltage, etc., and these power voltages may be sent to the unit pixel PX. A plurality of power lines VL may extend in the second direction DR2 and may be spaced apart from each other in the first direction DR1.

[0070] Sensing electrodes that detect a touch may be arranged in the display area DA. The sensing electrodes may include first sensing electrodes TSE1 disposed in the first direction DR1 and second sensing electrodes TSE2 disposed in the second direction DR2.

[0071] The non-display area NA may surround the display area DA. The gate driver 210, the fan-out line FOL, the gate control line GCL, the touch signal line TSL, etc. may be arranged in the non-display area NA. The gate driver 210 may generate a gate signal based on the gate control signal and supply the gate signal to the gate line GL in a set order. The fan-out line FOL may extend from the display driver 200 to the display area DA. The fan-out line FOL may send the data voltage output from the display driver 200 to the data line DL. The gate control line GCL may extend from the display driver 200 to the gate driver 210. The gate control line GCL may send the gate control signal output from the display driver 200 to the gate driver 210. The touch signal line TSL may electrically connect the touch pads (touch pads TP1, touch pads TP2) to the sensing electrodes (first sensing electrodes TSE1, second sensing electrodes TSE2).

[0072] The display panel 100 may include a sub-region SA. The display driver 200 may be located in the sub-region SA. The sub-region SA may include a pad region PA to which the flexible printed circuit board 300 is connected.

[0073] The display driver 200 may output signals and voltages for driving the display panel 100. The display driver 200 may supply a data voltage to the data line DL through the fan-out line FOL. The data voltage may be supplied to the unit pixel PX, and the brightness of the unit pixel PX may be controlled by the data voltage. The display driver 200 may supply a gate control signal to the gate driver 210 through the gate control line GCL.

[0074] The pad area PA may be formed at the edge of the sub-area SA. The pad area PA may include a display pad area DPA, a first touch pad area TPA1, and a second touch pad area TPA2. The display pad DP may be arranged in the display pad area DPA. The display pad DP may be connected to the graphics system through the flexible printed circuit board 300. The display pad DP is connected to the flexible printed circuit board 300, and may receive digital video data and supply the digital video data to the display driver 200. The first touch pad area TPA1 and the second touch pad area TPA2 may be located on opposite sides of the display pad area DPA. For example, the display pad area DPA may be arranged in the space between the first touch pad area TPA1 and the second touch pad area TPA2. The first touch pad area TPA1, the display pad area DPA, and the second touch pad area TPA2 may be arranged along the first direction DR1. The touch pad TP1 and the touch pad TP2 may be arranged in the first touch pad area TPA1 and the second touch pad area TPA2, respectively. The touch pads TP1 and the touch pads TP2 may be connected to the first and second sensing electrodes TSE1 and TSE2 located in the display area DA and the touch driver 400 located on the flexible printed circuit board 300 to detect a touch. The pad area PA, the first touch pad area TPA1, and the second touch pad area TPA2 are electrically connected to the flexible printed circuit board 300 through an anisotropic conductive film (ACF) or a self-assembled anisotropic conductive adhesive (SAP).

[0075] Figure 4 is a rear view of a display device according to an embodiment of the present disclosure, Figure 5 According to the embodiment of the present disclosure Figure 4 A schematic cross-sectional view taken along line AA' in FIG. Figure 6 According to the embodiment of the present disclosure Figure 4 A cross-sectional view taken along line BB' in FIG. Figure 7 is a rear view of a display device according to an embodiment of the present disclosure, and Figure 8 According to the embodiment of the present disclosure Figure 7 A cross-sectional view taken along line CC'. Fig. 9 is a cross-sectional view of a display device according to a comparative example.

[0076] Figure 4 , Figure 5 and Figure 6 The sub-area SA of the display panel 100 and the area in which the flexible printed circuit board 300 is positioned in the display device 30 according to the embodiment are shown. Figure 7 and Figure 8 It shows Figure 4 and Figure 6The tail portion 330 of the flexible printed circuit board 300 in the display device 30 shown in FIG. 1 is bent.

[0077] The display panel 100 may be attached to the cover window 10 through an adhesive layer 40 such as an optically clear adhesive (OCA).

[0078] The sub-region SA of the display panel 100 may include a bending portion BP, and the bending portion BP is bent so that a portion of the sub-region SA is located on the back side of the main region MA, and the display driver 200 located in the sub-region SA may be located on the back side of the main region MA. In order to maintain the bending state of the sub-region SA, the sub-region SA may be attached to the back side of the main region MA using a spacer SP including an adhesive layer 40 on opposite sides or a double-sided tape. When the sub-region SA is bent, the flexible printed circuit board 300 in which the extrusion portion 320 is bonded to the pad area PA of the sub-region SA may be located on the back side of the main region MA. The main body 310 of the flexible printed circuit board 300 may be attached to the back side of the main region MA using a double-sided tape DST or a spacer SP including an adhesive layer 40 on both sides.

[0079] In the flexible printed circuit board 300, the tail portion 330 may extend from the body portion 310. The tail portion 330 may have fewer layers and a smaller thickness than the body portion 310.

[0080] For example, the body portion 310 may have four layers or more, and the tail portion 330 may have three layers or less. For example, the body portion 310 may have six layers, and the tail portion 330 may have two layers.

[0081] The tail portion 330 may include a first portion 331 extending from the main body portion 310 in the second direction DR2 and a second portion 332 extending from the first portion 331 in a direction parallel to the first direction DR1. The connection terminal 340 may be located at an end of the second portion 332. In order to secure more space above the flexible printed circuit board 300 in the electronic device 1, the tail portion 330 may be bent. For example, Figure 7 and Figure 8 As shown in , the first portion 331 of the tail 330 may be bent around the axis X. The axis X may be parallel to the first direction DR1. Therefore, at least a portion of the second portion 332 of the tail 330 may overlap with the main body 310, and the space above the flexible printed circuit board 300 may be larger than the space before the tail 330 is bent, and it may extend by about the width of the tail 330. For example, the length of the flexible printed circuit board 300 may reduce the width of the tail 330 in the second direction DR2. As the area occupied by the flexible printed circuit board 300 is reduced, the space utilization within the electronic device 1 is increased, and, for example, the area in which the battery can be placed may be increased.

[0082] The bent portion of the tail portion 330 may be pressed in the third direction DR3 by the structure S or other components in the housing 20. For this reason, for example, Fig. 9 As shown in FIG. 1 , the adhesive layer 40 between the display panel 100 and the cover window 10 may be squeezed. The squeezed portion (ie, the recessed portion) of the adhesive layer 40 may be visible as a stain through the cover window 10. In order to reduce the squeezing phenomenon of the adhesive layer 40, as shown in FIG. Figure 4 , Figure 6 , Figure 7 and Figure 8 As shown in , the buffer layer 50 may be positioned between the main area MA and the first portion 331 of the tail portion 330, and the first portion 331 may overlap the buffer layer 50. For example, the first portion 331 may be bent around the axis X, and the bent portion of the first portion 331 may vertically overlap the buffer layer 50. The buffer layer 50 may be positioned between the second portion 332 of the tail portion 330 and the main body portion 310 in the second direction DR2. The buffer layer 50 may be attached to the back surface of the display panel 100 using an adhesive AD such as a pressure sensitive adhesive (PSA).

[0083] The buffer layer 50 can relieve the local pressure on the display panel 100 and the adhesive layer 40 by dispersing the extrusion stress caused by the bent portion when the first portion 331 of the tail portion 330 is bent. The buffer layer 50 can increase the extrusion range of the adhesive layer 40, but since the extrusion degree (depth) is reduced, the extruded portion of the adhesive layer 40 can become invisible. By positioning the buffer layer 50 between the bent portion of the tail portion 330 and the display panel 100, the bent portion of the tail portion 330 can be in contact with the buffer layer 50 and not in contact with the display panel 100.

[0084] The buffer layer 50 may have a substantially square planar shape, but may also have various planar shapes suitable for dispersing the stress applied by the curved portion of the tail 330, such as a circular shape and an elliptical shape. If the area of ​​the buffer layer 50 is large, it may be advantageous to widely distribute the stress, but the size of the buffer layer 50 may be designed in consideration of interference with other structures or components inside the electronic device 1. The width of the buffer layer 50 in the first direction DR1 may be greater than or equal to the width of the first portion 331 of the tail 330 in the first direction DR1. The width of the buffer layer 50 in the second direction DR2 may be about 2.0 mm to about 5.0 mm, or about 3.0 mm to about 4.0 mm, for example, about 3.5 mm. The buffer layer 50 may have a thickness of about 0.2 mm or less (e.g., about 0.05 mm to about 0.2 mm).

[0085] The compressive stress may be increased by the thickness of the buffer layer 50, but if the thickness of the buffer layer 50 is too thin, it may be difficult to disperse the stress. The distance between the buffer layer 50 and the main body 310 in the second direction DR2 may be about 0.1 mm to about 5.0 mm. In order to allow the compressive stress to be widely distributed throughout the buffer layer 50, the buffer layer 50 may have a relatively high modulus (also referred to as elastic modulus) or a relatively high stiffness. For example, the buffer layer 50 may have a modulus of about 10 GPa or greater or about 100 GPa or greater. The buffer layer 50 may be made of a metal or a metal alloy (e.g., stainless steel (also referred to as stainless steel (SUS) or steel-type stainless steel (STS))). The buffer layer 50 may be made of a polymer or ceramic material such as polyethylene terephthalate and polyimide. The flexible printed circuit board 300 having the main body portion 310 of 6 layers and 0.3 mm thick and the tail portion 330 of 2 layers and 0.12 mm thick was used to simulate the compression of the adhesive layer 40 during the bending of the tail portion 330. When the buffer layer 50 of 0.08 mm thick made of stainless steel and the adhesive AD of 0.05 mm thick were applied, the pressure applied to the adhesive layer 40 by the bent portion of the tail portion 330 was about 27% (of the pressure when the buffer layer 50 was not applied) compared to the case where the buffer layer 50 was not applied as in the comparative example.

[0086] At least a portion of the display driver 200, the sub-area SA, and the flexible printed circuit board 300 may be covered by the cover CVR. The cover CVR may be attached to the display driver 200, the sub-area SA, and the flexible printed circuit board 300. The cover CVR may cover at least a portion of the display driver 200 and the flexible printed circuit board 300 to protect them from electromagnetic interference (EMI) and electrostatic discharge (ESD). The cover CVR may prevent the display driver 200, the extrusion portion 320, etc. from contacting external objects and protect them from physical damage caused by friction. The tail 330 of the flexible printed circuit board 300 may not be covered by the cover CVR. The cover CVR can be made of a flexible material that can shield EMI or ESD. For example, the cover CVR may be in the form of a tape including a metal layer. The metal layer of the cover CVR may include a metal foil, a metal fabric, or a metal mesh. The adhesive layer 40 may be located on one side of the cover CVR. For example, an adhesive AD may be applied to one side of the cover CVR, or a double-sided tape DST may be attached to one side of the cover CVR.

[0087] In an implementation, the display panel 100 may include a display unit DU, a touch sensing unit (not shown) and a reflection reducing layer ARL disposed on the display unit DU, and a protection film PF and a protection sheet PS disposed under the display unit DU.

[0088] The display unit DU may include a substrate, and a driving element layer, a light emitting element layer, and an encapsulation layer located on the substrate.

[0089] The substrate may be a base substrate or a base member. The substrate may be a flexible substrate including a polymer resin such as polyimide, polyamide, and polyethylene terephthalate. The substrate may be a rigid substrate made of a material such as glass.

[0090] The driving element layer may be located on the substrate. The driving element layer may include transistors and capacitors constituting pixel circuit units that output drive current to light-emitting elements. The driving element layer may include gate lines, data lines, power lines, gate control lines, fan-out lines connecting the display driver 200 to the data lines, and leads connecting the display driver 200 to the display pad DP. The driving element layer may include transistors and capacitors constituting the gate driver and gate control lines. The driving element layer may include a conductive layer, a semiconductor layer, and an insulating layer. A plurality of insulating layers may be configured to insulate transistors, capacitors, and signal lines through their combination.

[0091] The light emitting element layer may be located on the driving element layer and may include a light emitting element and a corresponding light emitting region. The light emitting element layer may include a pixel defining layer having an opening defining a light emitting region.

[0092] The encapsulation layer (or referred to as a thin film encapsulation layer) may cover the top and side surfaces of the light emitting element layer and prevent moisture or oxygen from penetrating into the light emitting element layer from the outside. The encapsulation layer may include one or more inorganic layers and one or more organic layers.

[0093] The touch sensing unit may include an encapsulation layer, and may include first and second sensing electrodes TSE1 and TSE2. The first and second sensing electrodes TSE1 and TSE2 may sense a user's touch using a mutual capacitance method and / or a self capacitance method.

[0094] The reflection reducing layer ARL may reduce the amount of light incident on the display panel 100 from the outside and reflected by the display panel 100. The reflection reducing layer ARL may include a polarizing layer. The reflection reducing layer ARL may include a combination of a color filter and a light blocking member instead of the polarizing layer.

[0095] The protective film PF can be attached to the back side of the substrate, which will refer to Fig.12 The display panel 100 may be protected during the manufacturing process of the display device 30. The protection film PF may not be located in the bent portion BP of the sub-area SA. A bending protection layer BPL (or stress neutralization layer) may be located on the bent portion BP to relieve stress applied to the wiring located in the bent portion BP.

[0096] The protective sheet PS may be attached to the back of the protective film PF, and may protect the display panel 100 from the environment (e.g., impact, electromagnetic waves, heat, noise, etc.) behind the display panel 100. The protective sheet PS may be located in the main area MA but not in the sub-area SA. The protective sheet PS may have a structure in which a shielding layer SDL, a support layer SPL, and a buffer layer CSL are laminated. The protective sheet PS may define the rear surface of the display panel 100. The above-mentioned buffer layer CSL may be attached to the back of the protective sheet PS, or may be in contact with the back of the protective sheet PS.

[0097] The shielding layer SDL may prevent EMI from flowing into the display panel 100 from the rear surface of the display panel 100. The shielding layer SDL may be a metal layer including a metal having excellent shielding performance and thermal conductivity, such as copper and aluminum.

[0098] The support layer SPL may be provided to ensure the strength of the protection sheet PS and couple / separate the buffer layer CSL from other layers or members. The support layer SPL may be a plastic layer made of a polymer such as polyethylene terephthalate and polyimide.

[0099] The buffer layer CSL may absorb impact and prevent the display panel 100 from being damaged. For example, the buffer layer CSL may prevent damage to the display panel 100 caused by external impact by alleviating impact and stress applied when the electronic device 1 falls. The buffer layer CSL may be a porous layer formed of a material such as polyurethane and polyethylene. The buffer layer CSL may include a foamed resin or may be formed of a foamed resin.

[0100] Adhesive layers such as pressure sensitive adhesive (PSA) may be located between the shielding layer SDL and the support layer SPL and between the support layer SPL and the buffer layer CSL to attach them to each other. In addition to the above layers, the protection sheet PS may further include functional layers such as a light blocking layer and a heat dissipation layer.

[0101] Fig.10 and Fig.11 is a schematic cross-sectional view of a display device according to an embodiment of the present disclosure.

[0102] Fig.10 and Fig.11 It can be shown along Figure 4 The section taken along the line BB' in Figure 7 The cross section is taken along the line CC'. Fig.10 and Fig.11 The implementation method and Figure 6 and Figure 8The embodiment of the present invention is similar to that of the embodiment of the present invention, but is different in that the buffer layer 50 is attached to the tail portion 330 of the flexible printed circuit board 300. That is, the buffer layer 50 is attached to the first portion 331 of the tail portion 330 using the adhesive AD, rather than being attached to the back surface of the display panel 100. For the natural bending of the first portion 331 of the tail portion 330, the adhesive AD may be applied with a width narrower than the width of the buffer layer 50 in the second direction DR2, and the adhesive AD may not be located in the portion of the buffer layer 50 located away from the main body portion 310. That is, the portion of the buffer layer 50 located away from the main body portion 310 in the second direction DR2 may not be attached to the first portion 331. If the entire buffer layer 50 is attached to the first portion 331 of the tail portion 330, the buffer layer 50 holds the first portion 331, thereby interfering with the bending of the first portion 331 around the axis X. The width of the adhesive AD in the second direction DR2 may be about two-thirds or less, about half or less, or about one-third or less of the width of the buffer layer 50. About two thirds or less, about half or less, or about one third or less of the planar area of ​​the buffer layer 50 may be attached to the first portion 331 using the adhesive AD.

[0103] Although not shown, the buffer layer 50 may be attached to both the back surface of the display panel 100 and the first portion 331 of the tail portion 330. Fig.10 In the embodiment shown in Figure 6 The adhesive AD shown in FIG. 1 may be positioned between the buffer layer 50 and the display panel 100 .

[0104] Fig.12 is a schematic cross-sectional view of a display panel according to an embodiment of the present disclosure.

[0105] refer to Fig.12 , the cross-sectional view shows one pixel region. The display panel 100 includes a substrate SB, a transistor TR formed on the substrate SB, and a light emitting diode LED connected to the transistor TR. The light emitting diode LED may correspond to a pixel PX.

[0106] The substrate SB may be a flexible substrate that can be bent, folded, curled, etc. The substrate SB may be a multilayer including a first base layer BL1, an inorganic layer IL, and a second base layer BL2. The first base layer BL1 and the second base layer BL2 may include a polymer resin such as polyimide, polyamide, and polyethylene terephthalate. A barrier layer BR may be positioned on the substrate SB to prevent moisture, oxygen, etc. from penetrating into the light emitting diode LED. The barrier layer BR may include a silicon nitride (SiN x ), silicon oxide (SiO x ) and silicon oxynitride (SiO x N y) or an inorganic insulating material such as silicon nitride (SiN x ), silicon oxide (SiO x ) and silicon oxynitride (SiO x N y ) is formed of an inorganic insulating material and can be a single layer or a multilayer.

[0107] The buffer layer BF may be positioned on the barrier layer BR. The buffer layer BF may improve the characteristics of the semiconductor layer by blocking the diffusion of impurities into the substrate SB when the semiconductor layer is formed, and may relieve the stress of the semiconductor layer by flattening the surface of the substrate SB. The buffer layer BF may include or be formed of an inorganic insulating material such as silicon nitride, silicon oxide, and silicon oxynitride, and may be a single layer or a multilayer. The buffer layer BF may include or be formed of amorphous silicon (a-Si).

[0108] The semiconductor layer AL of the transistor TR may be located on the buffer layer BF. The semiconductor layer AL may include a first region, a second region, and a channel region between these regions. The semiconductor layer AL may include any one of amorphous silicon, polycrystalline silicon, and an oxide semiconductor or may be formed of any one of amorphous silicon, polycrystalline silicon, and an oxide semiconductor. The oxide semiconductor may include at least one of zinc (Zn), indium (In), gallium (Ga), and tin (Sn). For example, the semiconductor layer AL may include low temperature polycrystalline silicon (LTPS) or indium gallium zinc oxide (IGZO) or may be formed of low temperature polycrystalline silicon (LTPS) or indium gallium zinc oxide (IGZO).

[0109] A first gate insulating layer GI1 may be located on the semiconductor layer AL.

[0110] The first gate insulating layer GI1 may include or may be formed of an inorganic insulating material such as silicon nitride, silicon oxide, and silicon oxynitride, and may be a single layer or a multi-layer.

[0111] On the first gate insulating layer GI1, a first gate conductive layer that may include a gate electrode GE of the transistor TR, a gate line GL, and a first electrode C1 of the storage capacitor CS may be positioned. The first gate conductive layer may include or may be formed of molybdenum (Mo), aluminum (Al), copper (Cu), or titanium (Ti), and may be a single layer or a multilayer.

[0112] The second gate insulating layer GI2 may be on the first gate conductive layer. The second gate insulating layer GI2 may include or be formed of an inorganic insulating material such as silicon nitride, silicon oxide, and silicon oxynitride, and may be a single layer or multiple layers.

[0113] A second gate conductive layer including a second electrode C2 of the storage capacitor CS may be positioned on the second gate insulating layer GI2. The second gate conductive layer may include molybdenum (Mo), aluminum (Al), copper (Cu), or titanium (Ti), and may be a single layer or multiple layers.

[0114] The interlayer insulating layer ILD may be positioned on the second gate insulating layer GI2 and the second gate conductive layer. The interlayer insulating layer ILD may include or be formed of an inorganic insulating material such as silicon nitride, silicon oxide, and silicon oxynitride, and may be a single layer or multiple layers.

[0115] The first data conductive layer including the first electrode SE and the second electrode DE of the transistor TR and the data line DL may be located on the interlayer insulating layer ILD. The first electrode SE and the second electrode DE may be connected to the first region and the second region of the semiconductor layer AL respectively through the contact holes of the first gate insulating layer GI1, the second gate insulating layer GI2, and the interlayer insulating layer ILD. One of the first electrode SE and the second electrode DE may be a source electrode, and the other may be a drain electrode. The first data conductive layer may include or be formed of metals such as aluminum (Al), platinum (Pt), palladium (Pd), silver (Ag), magnesium (Mg), gold (Au), nickel (Ni), neodymium (Nd), iridium (Ir), chromium (Cr), calcium (Ca), molybdenum (Mo), titanium (Ti), tungsten (W), and copper (Cu), and may be a single layer or a multilayer.

[0116] The first planarization layer VIA1 may be located on the first data conductive layer. The first planarization layer VIA1 may include or be formed of an organic insulating material such as a general polymer (such as poly(methyl methacrylate) and polystyrene), a polymer derivative having a phenol group, an acrylic polymer, an imide polymer (e.g., polyimide), a siloxane polymer, etc.

[0117] The second data conductive layer, which may include a power line VL and a connection member CM, may be located on the first planarization layer VIA1. The power line VL may transmit voltages such as a driving voltage, a common voltage, an initialization voltage, and a reference voltage. The connection member CM may be connected to the second electrode DE of the transistor TR through a contact hole in the first planarization layer VIA1. The second data conductive layer may include aluminum (Al), platinum (Pt), palladium (Pd), silver (Ag), magnesium (Mg), gold (Au), nickel (Ni), neodymium (Nd), iridium (Ir), chromium (Cr), calcium (Ca), molybdenum (Mo), titanium (Ti), tungsten (W), or copper or may be formed of aluminum (Al), platinum (Pt), palladium (Pd), silver (Ag), magnesium (Mg), gold (Au), nickel (Ni), neodymium (Nd), iridium (Ir), chromium (Cr), calcium (Ca), molybdenum (Mo), titanium (Ti), tungsten (W), or copper, and may be a single layer or multiple layers.

[0118] The second planarization layer VIA2 may be located on the second data conductive layer. The second planarization layer VIA2 may include or be formed of an organic insulating material such as a general polymer (such as poly(methyl methacrylate) and polystyrene), a polymer derivative having a phenol group, an acrylic polymer, an imide polymer, and a siloxane polymer.

[0119] The first electrode E1 of the light emitting diode LED may be located on the second planarization layer VIA2. The first electrode E1 may be referred to as a pixel electrode. The first electrode E1 may be connected to the connection member CM through a contact hole in the second planarization layer VIA2. Therefore, the first electrode E1 is electrically connected to the second electrode DE of the transistor TR, and may receive a driving current that controls the brightness of the light emitting diode LED. The transistor TR to which the first electrode E1 is connected may be a driving transistor or a transistor electrically connected to the driving transistor. The first electrode E1 may be formed of a reflective conductive material or a translucent conductive material, or may be formed of a transparent conductive material. The first electrode E1 may include a transparent conductive material such as indium tin oxide (ITO) and indium zinc oxide (IZO). The first electrode E1 may include lithium (Li), calcium (Ca), aluminum (Al), silver (Ag), magnesium (Mg), gold (Au), etc.

[0120] The pixel defining layer PDL may be positioned on the second planarization layer VIA2 and the first electrode E1. The pixel defining layer PDL may be referred to as a bank or a partition wall, and may have an opening overlapping the first electrode E1. The pixel defining layer PDL may include or may be formed of an organic insulating material such as a general polymer (such as poly(methyl methacrylate) and polystyrene), a polymer derivative having a phenol group, an acrylic polymer, an imide polymer, and a siloxane polymer.

[0121] The light emitting layer EL of the light emitting diode LED may be positioned on the first electrode E1. In addition to the light emitting layer EL, a functional layer including at least one of a hole injection layer, a hole transport layer, an electron transport layer, and an electron injection layer may be positioned on the first electrode E1.

[0122] The second electrode E2 of the light emitting diode LED may be located on the light emitting layer EL. The second electrode E2 may be referred to as a common electrode. The second electrode E2 provides light transparency by forming a thin layer of a metal or metal alloy having a low work function, such as calcium (Ca), barium (Ba), magnesium (Mg), aluminum (Al), and silver (Ag). The second electrode E2 may include or may be formed of a transparent conductive oxide such as indium tin oxide (ITO) and indium zinc oxide (IZO).

[0123] The first electrode E1, the light emitting layer EL, and the second electrode E2 of each pixel PX may form a light emitting diode LED such as an organic light emitting diode. The first electrode E1 may be an anode, and the second electrode E2 may be a cathode. The light emitting region of the light emitting diode LED may correspond to the pixel PX.

[0124] The capping layer CPL may be positioned on the second electrode E2. The capping layer CPL may improve light efficiency by adjusting the refractive index. The capping layer CPL may be positioned to completely cover the second electrode E2. The capping layer CPL may include or may be formed of an organic insulating material or an inorganic insulating material.

[0125] The encapsulation layer EN may be located on the capping layer CPL. The encapsulation layer EN may seal the light emitting diode LED and prevent moisture or oxygen from penetrating from the outside.

[0126] The encapsulation layer EN may be a thin film encapsulation layer in which the organic layer EOL is located between the first inorganic layer EIL1 and the second inorganic layer EIL2 .

[0127] The touch sensor layer TS including the touch electrodes may be positioned on the encapsulation layer EN. The reflection reducing layer ARL may be positioned on the touch sensor layer TS to reduce external light reflection.

[0128] The protective film PF may be located under the substrate SB. The protective film PF may protect the display panel 100 during the manufacturing process of the display device 30. The protective film PF may include a polymer such as polyethylene terephthalate, a silicon-based polymer (eg, polydimethylsiloxane), and an elastomer (eg, elastomeric polyurethane).

[0129] The protective sheet PS may be located below the protective film PF. For example, the protective sheet PS may have the Figure 5 The structure of the description.

[0130] Although the embodiments have been described in detail above, the scope of the inventive concept is not limited thereto, and various modifications and improvements are possible by those skilled in the art using the basic concept defined in the appended claims.

Claims

1. A display device, comprising: A display panel, the display panel comprising a pad area; a flexible printed circuit board connected to the display panel; as well as a buffer layer, the buffer layer being arranged between the display panel and the flexible printed circuit board, The flexible printed circuit board includes: a main body, on which a component is arranged; a connecting portion, which is arranged along a first edge of the main body and is coupled to the pad area; and a tail portion, which extends from a second edge of the main body opposite to the first edge, and Wherein, the tail portion vertically overlaps with the buffer layer.

2. The display device according to claim 1, in, The tail portion includes a curved portion, and Wherein, the bent portion vertically overlaps with the buffer layer.

3. The display device according to claim 2, in, The connecting portion extends in a first direction parallel to a shorter side of the display panel, Wherein, the tail includes: a first portion extending from the second edge of the main body portion in a second direction parallel to a longer side of the display panel and intersecting the first direction; and a second portion extending from the first portion in the first direction, and Wherein, the first portion is bent around an axis parallel to the first direction.

4. The display device according to claim 3, in, At least a portion of the second portion overlaps the main body portion.

5. The display device according to claim 1, in, The first width of the buffer layer is equal to or greater than the second width of the tail portion, and The first width and the second width are measured along a first direction parallel to a shorter side of the display panel.

6. The display device according to claim 5, in, The buffer layer is made of stainless steel.

7. The display device according to claim 1, in, The buffer layer is attached to a rear surface of the display panel.

8. The display device according to claim 1, in, The buffer layer is attached to the tail portion.

9. The display device according to claim 8, in, The buffer layer is attached to the tail portion using an adhesive layer, wherein the adhesive layer is arranged between a portion of the buffer layer and the tail portion, wherein the portion of the buffer layer is attached to the tail portion using the adhesive layer, and The portion of the buffer layer corresponds to two-thirds or less of a planar area of ​​the buffer layer.

10. The display device according to claim 1, further comprising: a cover window, the cover window overlapping the display panel; as well as An adhesive layer is disposed between the display panel and the cover window.

Images