Display device

Abstract

In a display device, a flexible flat cable (1) connecting a first circuit substrate (DA) and a second circuit substrate (TC) is bent at a plurality of bending positions in a manner that the back surface of a first end thereof faces the backlight side and the surface of a second end thereof faces the backlight side, the first end being connected to a first connector (KA) of the first circuit substrate, and the second end being connected to a second connector (CB) of the second circuit substrate.

Description

Technical Field

[0001] The present invention relates to a display device. Background Art

[0002] Patent Document 1 discloses a configuration in which a control substrate and a circuit substrate of a drive system are connected via a flexible printed cable in a liquid crystal display device.

[0003] Prior art literature

[0004] Patent Literature

[0005] Patent Document 1: Japanese Patent Publication No. 2007-310184 Summary of the Invention

[0006] Technical problems to be solved by the present invention

[0007] A liquid crystal display device includes a display panel comprising a color filter substrate (CF substrate) and an active matrix substrate (TFT substrate); a backlight that illuminates the display panel; a first circuit substrate for the drive system; and a second circuit substrate serving as a control substrate. The first circuit substrate is connected to the end of the surface of the TFT substrate facing the CF substrate (hereinafter referred to as the "CF-facing surface") via a flexible wiring substrate. The second circuit substrate is connected to the first circuit substrate via an FFC.

[0008] In liquid crystal display devices, it's common practice to position the TFT substrate closer to the backlight than the CF substrate. In conventional configurations where the TFT substrate is positioned closer to the backlight than the CF substrate, the CF-facing surface of the TFT substrate faces the viewer, and consequently, the surface of the first circuit substrate (the connector mounting surface) faces away from the backlight. Therefore, FFC connection can be performed with the surface of the second circuit substrate (the connector mounting surface) facing away from the backlight (i.e., with the connector visible to the operator).

[0009] On the other hand, the inventors' research has revealed that as the backlight brightness increases, the TFT substrate may malfunction. As a countermeasure, they have discovered that placing the CF substrate closer to the backlight side than the TFT substrate is an effective solution. In this new configuration where the CF substrate is placed closer to the backlight side than the TFT substrate, the CF-facing surface of the TFT substrate faces the backlight side, and consequently, the surface of the first circuit substrate (the connector mounting surface) faces the backlight side. When connecting a second circuit substrate to a first circuit substrate whose surface faces the backlight side via an FFC, the FFC connection operation typically needs to be performed with the second circuit substrate's surface facing the backlight side (i.e., the connector is not visible to the operator), resulting in reduced operational efficiency.

[0010] Technical solutions to technical problems

[0011] The display device according to the present disclosure includes a display panel, a backlight that irradiates light to the display panel, at least one first circuit substrate that has at least one first connector and is disposed in the vicinity of the backlight with a surface on which the at least one first connector is mounted facing the backlight side, a second circuit substrate that has at least one second connector and is disposed in the vicinity of the backlight with a back surface opposite to a surface on which the at least one second connector is mounted facing the backlight side, and at least one FFC (Flexible Flat Cable) that connects the first circuit substrate and the second circuit substrate, the at least one FFC being bent at a plurality of bending positions with one of a surface and a back surface in a first end of the at least one FFC facing the backlight side and the other of a surface and a back surface in a second end of the at least one FFC facing the backlight side, the first end being connected to the first connector, and the second end being connected to the second connector.

[0012] Advantageous Effects

[0013] In one embodiment of the present application, even in a case where a surface of the first circuit substrate faces the backlight side, the connection work of the FFC can be performed in a state where a surface of the second circuit substrate faces a side opposite to the backlight, and thus a decrease in work efficiency when manufacturing the display device can be suppressed. BRIEF DESCRIPTION OF DRAWINGS

[0014] Figure 1A is a plan view showing a back surface configuration of the display device of the present embodiment.

[0015] Figure 1B is an enlarged view of a part of Figure 1A .

[0016] Figure 2 is a cross-sectional view showing a part of the A-A cross section of Figure 1B .

[0017] Figure 3 is a cross-sectional view showing a part (lower portion) of the A-A cross section of Figure 1B .

[0018] Figure 4 is a cross-sectional view showing a part of the B-B cross section of Figure 1B .

[0019] Figure 5 is a cross-sectional view showing a part (lower portion) of the B-B cross section of Figure 1B .

[0020] Figure 6It is a plan view showing the structure of the FFC according to the first embodiment.

[0021] Figure 7 This is a plan view showing a connected state of a first circuit board and a second circuit board in the first embodiment.

[0022] Figure 8 It is a top view showing the bending method of FFC.

[0023] Figure 9 It is a top view showing the bending method of FFC.

[0024] Figure 10 It is a plan view showing another structure of the FFC.

[0025] Figure 11 It is a top view showing another bending method of FFC.

[0026] Figure 12 It is a plan view showing another connection state of the first circuit substrate and the second circuit substrate in the second embodiment.

[0027] Figure 13 It is a plan view showing the connection structure of the first circuit substrate and the second circuit substrate in the third embodiment.

[0028] Figure 14 It is a plan view showing another connection structure between the first circuit substrate and the second circuit substrate in the third embodiment.

[0029] Figure 15 It is a plan view showing the structure of an FFC according to a fourth embodiment.

[0030] Figure 16 It is a plan view showing the structure of an FFC according to a fourth embodiment.

[0031] Figure 17 It is a plan view showing the connection structure of the first circuit substrate and the second circuit substrate in the fourth embodiment.

[0032] Figure 18 It is a plan view showing the structure of an FFC according to a fifth embodiment.

[0033] Figure 19 It is a plan view showing the structure of an FFC according to a fifth embodiment.

[0034] Figure 20 It is a plan view showing the connection structure of the first circuit substrate and the second circuit substrate in the fifth embodiment. DETAILED DESCRIPTION

[0035] [First embodiment]

[0036] Figure 1A It is a plan view showing the back structure of the display device according to this embodiment. Figure 1B yes Figure 1A A magnified view of a portion of . Figure 2 Yes Figure 1B A cross-sectional view of a portion of section AA. Figure 3 Yes Figure 1B A cross-sectional view of a portion (lower part) of the AA section. Figure 4 Yes Figure 1B A cross-sectional view of a portion of the BB cross section. Figure 5 Yes Figure 1B A cross-sectional view of a portion (lower portion) of the BB section. Figure 1A and Figure 1B as well as Figures 2 to 5 As shown, the display device DS of this embodiment includes a display panel DP, a backlight BL that irradiates light to the display panel DP, at least one (two in this embodiment) first circuit substrate DA, DB, a second circuit substrate TC, and at least one (two in this embodiment) FFC (Flexible Flat Cable) 1, 2.

[0037] like Figure 3 and Figure 5 As shown, the display panel DP has a first polarizing plate P1, an active matrix substrate AK (TFT substrate), a liquid crystal layer, a color filter substrate CF, and a second polarizing plate P2 in order from the front side (visual recognition side) to the back side of the device. The liquid crystal layer is sandwiched between the active matrix substrate AK and the color filter substrate CF. The color filter substrate CF is arranged on the backlight BL side relative to the active matrix substrate AK. The backlight BL has a light source ES (see Figure 2 and Figure 4 ), backlight chassis BT, BS, and optical layer KS. The optical layer KS, for example, comprises a diffuser sheet and is disposed in the backlight BL at a position closest to the display panel DP. Hereinafter, the bottom of the backlight chassis is referred to as the "backlight bottom BT," and the side of the backlight chassis is referred to as the "backlight side BS." In the display device DS of this embodiment, light emitted from the backlight BL passes through the color filter substrate CF before entering the active matrix substrate AK. Therefore, the incident intensity on the active matrix substrate AK is reduced. This can prevent malfunctions of the active matrix substrate K.

[0038] The first circuit substrate DA, DB is at least one (two in this embodiment) source substrate connected to the second circuit substrate TC via FFC1, 2 among the multiple source substrates possessed by the display device DS. The first circuit substrate DA, DB is arranged near the backlight BL (the backlight side BS in this embodiment) and is connected to the end of the active matrix substrate AK via the flexible wiring substrate HK on which the source driver SD is installed. At least one first circuit substrate DA, DB has at least one (two in this embodiment) first connector KA, KB. In this embodiment, the first circuit substrate DA of one of the two first circuit substrates DA, DB has a first connector KA, and the first circuit substrate DB of the other has a first connector KB. In addition, a circuit substrate may also have multiple first connectors. The first circuit substrates DA, DB are arranged in such a way that the surface on which the first connectors KA, KB are installed (the surface recorded as "surface" in the figure) faces the backlight BL side. One end of the flexible wiring substrate HK is connected to the end of the CF-opposing surface of the active matrix substrate AK (the protruding portion not facing the color filter substrate CF), and the other end is connected to the end of the backlight BL-side surface of the first circuit substrate DA, DB.

[0039] The second circuit substrate TC is a control substrate, for example, a timing control substrate on which a timing controller is mounted. Figure 2 as well as Figure 4 As shown, the second circuit board TC is disposed near the backlight BL (the backlight base BT in this embodiment) and is connected to the display panel DP via the FFCs 1 and 2, the first circuit boards DA and DB, and the flexible wiring board HK. The second circuit board TC has at least one (two in this embodiment) second connectors CA and CB. The second circuit board TC is configured so that its back surface (the "back surface" in the figure), opposite to the surface (the "front surface" in the figure) on which the second connectors CA and CB are mounted, faces the backlight BL. In other words, the surface of the second circuit board TC faces the side opposite the backlight BL.

[0040] The above-described configuration of the display device DS is substantially the same in other embodiments. Hereinafter, the configurations of the FFCs 1 and 2 in this embodiment will be described in detail.

[0041] Figure 6 It is a plan view showing the structure of the FFC according to the first embodiment. Figure 7 1 is a top view showing the connection state of the first circuit substrate and the second circuit substrate in the first embodiment. Figure 6 as well as Figure 7 As shown, the first circuit substrate DA and the second circuit substrate TC are connected via the FFC1. The FFC1 has one of the front and back surfaces of its first end 1X (the front surface in this embodiment) facing the backlight BL side (at the Figure 7 The first end 1X is connected to the first connector KA, and the second end 1Y is connected to the second connector CB. The end portion included in the first part 11 described later of the FFC1 (one end of the FFC1) is the first end 1X, and the end portion included in the fourth part 14 described later (the other end of the FFC1) is the second end 1Y. FFC1 includes a plurality of wirings W (part of the wirings are recorded in the accompanying drawings). The plurality of wirings W extend in parallel from the first end 1X to the second end 1Y of the FFC1. The surface of the FFC1 (the gray part in the figure) is a shielding surface, and the back surface thereof (the white part in the figure) is a non-shielding surface.

[0042] like Figure 6 as well as Figure 7 As shown, the first circuit board DB and the second circuit board TC are connected via FFC2. FFC2 is bent at multiple (three, like FFC1) bending positions, with one of the front and back surfaces of its first end 2X (the same as FFC1) facing the backlight BL, and the other of the front and back surfaces of its second end 2Y (the same as FFC1) facing the backlight BL. The first end 2X is connected to the first connector KB, and the second end 2Y is connected to the second connector CA. The end included in the first portion 21 of FFC2, described later (one end of FFC2), is the second end 2Y, and the end included in the fourth portion 24, described later (the other end of FFC2), is the first end 2X. Like FFC1, FFC2 includes multiple wirings W. The multiple wirings W extend in parallel from the first end 2X to the second end 2Y of FFC2. The front surface of FFC2 (the gray portion in the figure) is the shielding surface, and the back surface (the white portion in the figure) is the non-shielding surface.

[0043] Figure 8 as well as Figure 9 This is a top view showing the bending method of FFC. Figure 6 as well as Figure 8 As shown, the FFC1 has multiple bending positions, including a first bending position 1F, a second bending position 1S, and a third bending position 1T. The FFC1 includes a first portion 11 extending from one end (first end 1X) to the first bending position 1F, a second portion 12 extending from the first bending position 1F to the second bending position 1S, a third portion 13 extending from the second bending position 1S to the third bending position 1T, and a fourth portion 14 extending from the third bending position 1T to the other end (second end 1Y). The FFC1 bends at the three bending positions 1F, 1S, and 1T, with the front surfaces of the first portion 11 and the third portion 13 and the back surfaces of the second portion 12 and the fourth portion 14 facing the backlight BL.

[0044] As Figure 6 and Figure 9 shown, the plurality of bending positions of the FFC2 include three bending positions of a first bending position 2F, a second bending position 2S, and a third bending position 2T. The FFC2 includes a first portion 21 from one end (second end 2Y) to the first bending position 2F, a second portion 22 from the first bending position 2F to the second bending position 2S, a third portion 23 from the second bending position 2S to the third bending position 2T, and a fourth portion 24 from the third bending position 2T to the other end (first end 2X). The FFC2 is bent at the three bending positions 2F, 2S, 2T in a manner that the back surfaces of the first and third portions 21, 23 each face the surface of the second and fourth portions 22, 24 toward the back light BL side.

[0045] Thus, the FFC1 and the FFC2 are bent in the same bending direction from the same length of FFC. Since the same kind of FFC having the same bending shape is used as the plurality of FFC1, 2, cost reduction can be achieved. The FFC1 and the FFC2 are connected to the first circuit substrates DA, DB and the second circuit substrate TC in a state where the surfaces and the backs thereof face in opposite directions. Since the bending manners of the FFC1 and the FFC2 are the same, the details of the bending method will be described below with the FFC1 as an example.

[0046] The plurality of wirings W extending from the first end 1X to the second end 1Y are provided in parallel in the FFC1. In a state where the FFC1 is bent, the plurality of wirings W are as shown below. That is, when the end portion 1 IE on the second portion 12 side of the first portion 11 is viewed from above, the wiring direction (the direction in which the wiring extends) on the end portion 1 IE is substantially orthogonal to the wiring direction of the end portion 12E of the first portion 11 side of the second portion 12. When the end portion 12e on the third portion 13 side of the second portion 12 is viewed from above, the wiring direction on the end portion 12e is substantially orthogonal to the wiring direction at the end portion 13E of the second portion 12 side of the third portion 13. When the end portion 13e on the fourth portion 14 side of the third portion 13 is viewed from above, the wiring direction on the end portion 13e is substantially antiparallel to the wiring direction at the end portion 14E of the third portion 13 side of the fourth portion 14.

[0047] As Figure 6 and Figure 8 shown, the FFC1 is bent at the first bending position IF in a manner that a part of the surface of the first portion 11 opposes a part of the surface of the second portion 12. In Figure 6 , the part of the first portion 11 overlapping the second portion 12 is located at a position closer to the front side of the paper than the second portion 12. Further, the FFC1 is bent at the second bending position IS in a manner that another part of the surface of the second portion 12 opposes a part of the surface of the third portion 13. In Figure 6In the figure, the portion of the third portion 13 that overlaps with the second portion 12 is located closer to the front side of the paper than the second portion 12. In addition, the FFC 1 is bent at the third bending position 1T so that the back surface of the third portion 13 faces a portion of the back surface of the fourth portion 14. Figure 6 In the figure, the portion of the fourth portion 14 that overlaps the third portion 13 is located closer to the front of the paper than the third portion 13. The first portion 11, the second portion 12, and the third portion 13 are each shaped like a trapezoid, and the fourth portion 14 is shaped like a rectangle.

[0048] In this embodiment, different wirings are intersected in the portions where the shielded surfaces (front surfaces) face each other, while the same wirings are overlapped in the portions where the non-shielded surfaces (back surfaces) face each other. By preventing different wirings from intersecting in the portions where the non-shielded surfaces (back surfaces) face each other, interference between wirings can be reduced.

[0049] like Figure 7 As shown, the first circuit substrate DA, DB and the second circuit substrate TC are connected via FFC1 and 2. Specifically, the first end 1X of FFC1 is connected to one of the two first connectors KA and KB (the first connector KA on the left side in the figure), and the second end 1Y of FFC1 is connected to one of the two second connectors CA and CB (the second connector CB on the right side in the figure). In addition, the first end 2X of FFC2 is connected to the other of the two first connectors KA and KB (the first connector KB on the right side in the figure), and the second end 2Y of FFC2 is connected to the other of the two second connectors CA and CB (the second connector CA on the left side in the figure). In this way, FFC1 and FFC2 are cross-configured and connected to the first circuit substrates DA and DB and the second circuit substrate TC.

[0050] FFC1 overlaps FFC1 and FFC2 in such a way that the back surface of the portion of second portion 12 that overlaps with first portion 11 (hereinafter referred to as the "first overlapping portion") faces the surface of first portion 21 of FFC2, and the back surface of the portion of second portion 22 of FFC2 that overlaps with first portion 21 (hereinafter referred to as the "second overlapping portion") faces the surface of first portion 11 of FFC1. Furthermore, third portion 13 and fourth portion 14 of FFC1 do not overlap any portion of FFC2, and third portion 23 and fourth portion 24 of FFC2 do not overlap any portion of FFC1. Furthermore, the entire back surface of the first overlapping portion does not necessarily face the surface of first portion 21 of FFC2. For example, FFC1 and FFC2 may overlap with a slight offset so that a portion of the back surface of the first overlapping portion does not face the surface of first portion 21 of FFC2. Similarly, the entire back surface of the second overlapping portion does not necessarily face the surface of the first portion 11 of FFC1. For example, FFC1 and FFC2 may overlap with each other slightly offset so that a portion of the back surface of the second overlapping portion does not face the surface of the first portion 11 of FFC1. The same applies to other embodiments.

[0051] Thus, in this embodiment, FFC1 and FFC2 overlap in such a way that their non-shielded surfaces (back surfaces) do not face each other. Thus, interference between wiring can be reduced. In addition, by staggering the first overlapping portion of FFC1 and the second overlapping portion of FFC2, the overall thickness of multiple FFC1 and 2 can be reduced. Furthermore, the connection relationship between the multiple terminals of the first connectors KA and KB and the multiple terminals of the second connectors CA and CB is the same as the previous situation in which the surface of the first circuit substrate and the surface of the second circuit substrate are set to the same direction and the FFC is not bent but directly connected. Therefore, there is no need to perform special processing such as left-right inversion of the image.

[0052] In FFC1, the portion of second portion 12 that overlaps with first portion 11 (first overlapping portion) is triangular in shape, the portion of third portion 13 that overlaps with second portion 12 is triangular in shape, and the portion of fourth portion 14 that overlaps with third portion 13 is trapezoidal in shape. In FFC2, the portion of second portion 22 that overlaps with first portion 21 (second overlapping portion) is triangular in shape, the portion of third portion 23 that overlaps with second portion 22 is triangular in shape, and the portion of fourth portion 24 that overlaps with third portion 23 is trapezoidal in shape.

[0053] According to the first embodiment, the FFCs 1 and 2 are bent at multiple (three in this embodiment) bending locations, with one of the front and back surfaces of their first ends 1X and 2X (the front surface in this embodiment) facing the backlight BL, and the other of the front and back surfaces of their second ends 1Y and 2Y (the back surface in this embodiment) facing the backlight BL. The FFCs 1 and 2 are arranged so as to intersect with each other. The first ends 1X and 2X are connected to the first connectors KA and KB, while the second ends 1Y and 2Y are connected to the second connectors CB and CA. Consequently, even in the case of a display device DS in which the color filter substrate CF is located closer to the backlight BL than the active matrix substrate AK, where the surfaces of the first circuit boards DA and DB face the backlight BL, the second ends 1Y and 2Y of the FFCs 1 and 2 can be inserted into the second connectors CA and CB of the second circuit board TC with the surface of the second circuit board TC facing away from the backlight BL (i.e., facing the operator). Therefore, the operator can connect the second connectors CA and CB to the FFCs 1 and 2 while observing the second connectors CA and CB of the second circuit board TC, thereby reducing the reduction in work efficiency. In addition, the first ends 1X and 2X of the FFCs 1 and 2 can be installed on the first circuit boards DA and DB before installing them.

[0054] [Second embodiment]

[0055] Figure 10 It is a plan view showing another structure of the FFC. Figure 11 This is a top view showing another FFC bending method. The components of FFCs 1' and 2' of the second embodiment are labeled with the same reference numerals as those of FFCs 1 and 2 of the first embodiment. The bending methods at the second bending locations 1S and 2S and the third bending locations 1T and 2T of FFCs 1' and 2' of the second embodiment differ from those of FFCs 1 and 2 of the first embodiment. The following describes the differences from the first embodiment using FFC 1' as an example.

[0056] When the FFC 1' is bent, the plurality of wires W are as follows. Specifically, when looking down at end 11E of the first portion 11 on the second portion 12 side, the wiring direction (the direction in which the wiring extends) at end 11E is approximately perpendicular to the wiring direction at end 12E of the second portion 12 on the first portion 11 side. When looking down at end 12e of the second portion 12 on the third portion 13 side, the wiring direction at end 12e is approximately opposite and parallel to the wiring direction at end 13E of the third portion 13 on the second portion 12 side. When looking down at end 13e of the third portion 13 on the fourth portion 14 side, the wiring direction at end 13e is approximately perpendicular to the wiring direction at end 14E of the fourth portion 14 on the third portion 13 side.

[0057] like Figure 10 as well as Figure 11 As shown, FFC1' is bent at the first bending position 1F in such a manner that a portion of the surface of the first portion 11 faces a portion of the surface of the second portion 12. Figure 10 In the figure, the portion of the first portion 11 that overlaps with the second portion 12 is located closer to the front side of the paper than the second portion 12. In addition, the FFC 1' is bent at the second bending position 1S so that a portion of the back surface of the second portion 12 faces the back surface of the third portion 13. Figure 10 In the figure, the portion of the second portion 12 that overlaps with the third portion 13 is located closer to the front side of the paper than the third portion 13. In addition, the FFC 1' is bent at the third bending position 1T so that a portion of the surface of the third portion 13 faces a portion of the surface of the fourth portion 14. Figure 10 In the figure, the portion of the third portion 13 that overlaps with the fourth portion 14 is located closer to the front of the paper than the fourth portion 14. The first portion 11, second portion 12, third portion 13, and fourth portion 14 of the FFC 1' are each trapezoidal in shape.

[0058] In the second embodiment, similar to the first embodiment, FFCs 1 and 2, different wirings are intersected in the portions where the shielded surfaces (front faces) face each other, and the same wirings are overlapped in the portions where the non-shielded surfaces (back faces) face each other. By preventing the different wirings from intersecting in the portions where the non-shielded surfaces (back faces) face each other, interference between the wirings can be reduced.

[0059] Figure 12 This is a top view showing the connection structure of the first circuit substrate and the second circuit substrate of the second embodiment. The first connectors KA and KB connected to the first ends 1X and 2X of FFC1' and 2' and the second connectors CA and CB connected to the second ends 1Y and 2Y are the same as those of the first embodiment. FFC1' and 2' in the second embodiment are arranged crosswise with each other in the same manner as FFC1 and 2 in the first embodiment. The back surface of the portion (first overlapping portion) of the second part 12 of FFC1' that overlaps with the first part 11 of FFC2' is opposite to the surface of the first part 21 of FFC2', and the back surface of the portion (second overlapping portion) of the second part 22 of FFC2' that overlaps with the first part 21 of FFC1' is overlapped in such a manner that it overlaps with the surface of the first part 11 of FFC1'. The third part 13 and the fourth part 14 of FFC1' do not overlap with any part of FFC2', and the third part 23 and the fourth part 24 of FFC2' do not overlap with any part of FFC1'.

[0060] In FFC1', the shape of the portion of the second portion 12 that overlaps with the first portion 11 (the first overlapping portion) is triangular, the shape of the portion of the second portion 12 that overlaps with the third portion 13 is trapezoidal, and the shape of the portion of the third portion 13 that overlaps with the fourth portion 14 is triangular. In FFC2', the shape of the portion of the second portion 22 that overlaps with the first portion 21 (the second overlapping portion) is triangular, the shape of the portion of the second portion 22 that overlaps with the third portion 23 is trapezoidal, and the shape of the portion of the third portion 23 that overlaps with the fourth portion 24 is triangular.

[0061] Even when the first circuit boards DA and DB are connected to the second circuit board TC via the FFCs 1' and 2' of the second embodiment, the same effects as those of the first embodiment can be achieved. Specifically, even when the surfaces of the first circuit boards DA and DB face the backlight BL, the FFCs 1' and 2' can be connected while the surface of the second circuit board TC faces the side opposite the backlight BL (i.e., when the second connectors CA and CB are visible to the operator). This can minimize any reduction in operating efficiency during the manufacture of the display device DS.

[0062] [Third embodiment]

[0063] Figure 13 It is a plan view showing the connection structure of the first circuit substrate and the second circuit substrate in the third embodiment. Figure 13 The display device DS includes: Figure 13 N (in this embodiment, N is an integer greater than or equal to 2, Figure 13 In the example of the embodiment, N=4 first connectors KA1~KA4; N second connectors CB1~CB4 arranged in parallel in the D2 direction when viewed from the backlight BL side; and N FFC1s arranged in parallel in the D2 direction when viewed from the backlight BL side. The N first connectors KA1~KA4 are arranged on a first circuit substrate DA, and the N second connectors CB1~CB4 are arranged on a second circuit substrate TC. Each of the N FFC1s is substantially the same as the FFC1 of the first embodiment. The surface of each FFC1 (the gray part in the figure) is a shielding surface, and the back surface is a non-shielding surface.

[0064] The nth (n is an integer from 1 to 4) FFC1 from the D2 side (e.g., the left side in the figure, hereinafter referred to as the "D2 side") among the N FFC1s has its first end 1X connected to the nth first connector KAn from the D2 side among the N first connectors KA1 to KA4, and its second end 1Y connected to the nth second connector CBn from the D2 side among the N second connectors CB1 to CB4. The first portion 11 of each of the N FFC1s is positioned further to the D2 side than the fourth portion 14. The mth (m is an integer from 2 to 4) FFC1 from the D2 side among the N FFC1s overlaps the (m-1)th FFC1 from the D2 side, with the back surface of the portion of its second portion 12 that overlaps with the first portion 11 (the first overlapping portion) facing the front surface of the second portion 12 of the (m-1)th FFC1 from the D2 side among the N FFC1s.

[0065] In this way, Figure 13 In the example, N FFC1s overlap so that their non-shielded surfaces (back surfaces) do not face each other. This reduces inter-wiring interference. In addition, by overlapping the first overlapping portions of the N FFC1s with their respective portions offset, the overall thickness of the N FFC1s can be reduced.

[0066] Figure 14 It is a plan view showing another connection structure of the first circuit substrate and the second circuit substrate according to the third embodiment. Figure 14 The display device DS includes: Figure 14 N (in this embodiment, N is an integer greater than 2, Figure 14 In the example (N=4), there are first connectors KB1 to KB4; N second connectors CA1 to CA4 arranged side by side in the D2 direction when viewed from the backlight BL side; and N FFC2s arranged side by side in the D2 direction when viewed from the backlight BL side. The N first connectors KB1 to KB4 are provided on a first circuit substrate DB, and the N second connectors CA1 to CA4 are provided on a second circuit substrate TC. Each of the N FFC2s is substantially the same as the FFC2 of the first embodiment. The surface of each FFC2 (the gray portion in the figure) is a shielding surface, and the back surface is a non-shielding surface.

[0067] The nth (n is an integer greater than 1 and less than 4) FFC2 from the D2 direction side among the N FFC2s has its first end 2X connected to the nth first connector KBn from the D2 direction side among the N first connectors KB1 to KB4, and its second end 2Y connected to the nth second connector CAn from the D2 direction side among the N second connectors CA1 to CA4. The first portion 21 of each of the N FFC2s is arranged at a position closer to the D2 direction side than the fourth portion 24. The mth (m is an integer greater than 2 and less than 4) FFC2 from the D2 direction side among the N FFC2s overlaps with the (m-1)th FFC2 from the D2 direction side in such a way that the back surface of the portion (second overlapping portion) of its second portion 22 that overlaps with the first portion 21 is opposite to the surface of the second portion 22 of the (m-1)th FFC2 from the D2 direction side among the N FFC2s.

[0068] In this way, Figure 14 In the example, N FFC2s overlap so that their non-shielded surfaces (back surfaces) do not face each other. This reduces interference between wirings. In addition, by staggering the second overlapping portions of the N FFC2s, the overall thickness of the N FFC2s can be reduced.

[0069] like Figure 13 and Figure 14 As shown, in a state where the surface of the first circuit substrate DA, DB (the mounting surface of the first connectors KA1 to KA4, KB1 to KB4) faces the backlight BL side, and the surface of the second circuit substrate TC (the mounting surface of the second connectors CA1 to CA4, CB1 to CB4) faces the side opposite to the backlight BL, the first circuit substrate DA, DB and the second circuit substrate TC are connected via N FFCs 1, 2. Therefore, in this embodiment, the same effect as that of the first embodiment can be obtained. That is, even in a case where the surface of the first circuit substrate DA, DB faces the backlight BL side, the connection operation of the FFCs 1, 2 can be performed in a state where the surface of the second circuit substrate TC faces the side opposite to the backlight BL (that is, in a state where the second connectors CA1 to CA4, CB1 to CB4 are visible to the operator), thereby suppressing a decrease in the operating efficiency when manufacturing the display device DS.

[0070] [Fourth embodiment]

[0071] Figure 15 and Figure 16 It is a plan view showing the structure of an FFC according to a fourth embodiment. Figure 17 It is a plan view showing the connection structure of the first circuit board and the second circuit board according to the fourth embodiment. Figure 17 The display device DS includes: Figure 17N (in this embodiment, N is an even number greater than 4, in the embodiment) arranged in parallel in the direction D2 when viewed from the back side of the paper. Figure 17 In the example, N=4) first connectors KA1, KA2, KB1, KB2; N second connectors CB1, CB2, CA1, CA2 arranged in parallel in the D2 direction when viewed from the backlight BL side; N / 2 FFC3s arranged in parallel in the D2 direction when viewed from the backlight BL side; and N / 2 FFC4s arranged in parallel in the D2 direction when viewed from the backlight BL side. Two first connectors KA1, KA2 of the N first connectors KA1, KA2, KB1, KB2 are provided on the first circuit substrate DA, and the other two first connectors KB1, KB2 are provided on the first circuit substrate DB. The N second connectors CB1, CB2, CA1, CA2 are all provided on the second circuit substrate TC. The N / 2 FFC3s are respectively substantially the same as the FFC1 of the first embodiment, and the N / 2 FFC4s are respectively substantially the same as the FFC2 of the first embodiment. The components of FFC3 are denoted by the same reference numerals as those of FFC1, and the components of FFC4 are denoted by the same reference numerals as those of FFC2. N / 2 FFC3s and N / 2 FFC4s have the same shape. N / 2 FFC3s and N / 2 FFC4s are connected to the first circuit board DA, DB and the second circuit board TC with their front and back surfaces facing oppositely. The front surface (gray area in the figure) of each FFC3 and 4 is a shielded surface, and the back surface is a non-shielded surface.

[0072] N / 2 FFCs 3 and N / 2 FFCs 4 are arranged crosswise and connected to the N first connectors KA1, KA2, KB1, KB2 of the first circuit boards DA and DB and the N second connectors CB1, CB2, CA1, CA2 of the second circuit board TC as follows. Specifically, the nth (n is an integer greater than 1 and less than N / 2) FFC 3 from the D2 side (the left side in the figure) among the N / 2 FFCs 3 has its first end 1X connected to the nth first connector KAn from the D2 side among the N first connectors KA1, KA2, KB1, KB2, and its second end 1Y connected to the (n+N / 2)th second connector CAn from the D2 side among the N second connectors CB1, CB2, CA1, CA2. In addition, the nth FFC4 from the D2 direction side among the N / 2 FFC4s has a first end 2X connected to the (n+N / 2)th first connector KBn from the D2 direction side among the N first connectors KA1, KA2, KB1, KB2, and a second end 2Y connected to the nth second connector CBn from the D2 direction side among the N second connectors CB1, CB2, CA1, CA2.

[0073] The first portions 11 of the N / 2 FFCs 3 are arranged on the D2 direction side of the fourth portions 14, and the first portions 21 of the N / 2 FFCs 4 are arranged on the D2 direction side of the fourth portions 24. Also, the mth (m is an integer of 2 or more and N / 2 or less) FFC 3 from the D2 direction side of the N / 2 FFCs 3 overlaps the (m-1)th FFC 3 from the D2 direction side of the N / 2 FFCs 3 in such a manner that the back surface of the portion (first overlap portion) of the second portion 12 of the mth FFC 3 that overlaps the first portion 11 overlaps the surface of the second portion 12 of the (m-1)th FFC 3. Also, the mth FFC 4 from the D2 direction side of the N / 2 FFCs 4 overlaps the (m-1)th FFC 4 from the D2 direction side of the N / 2 FFCs 4 in such a manner that the back surface of the portion (second overlap portion) of the second portion 22 of the mth FFC 4 that overlaps the first portion 21 overlaps the surface of the second portion 22 of the (m-1)th FFC 4.

[0074] In Figure 17 the N / 2 FFCs 3, the FFC 3 (hereinafter referred to as "FFC 5") on the most D2 direction side overlaps the first portion 21 of the FFC 4 (hereinafter referred to as "FFC 6") on the most D2 direction side of the N / 2 FFCs 4 in such a manner that the back surface of the portion (first overlap portion) of the second portion 12 of the FFC 5 that overlaps the first portion 11 overlaps the surface of the first portion 21 of the FFC 6, and the FFC 6 overlaps the N / 2 FFCs 3 and the N / 2 FFCs 4 in such a manner that the back surface of the portion (second overlap portion) of the second portion 22 of the FFC 6 that overlaps the first portion 21 overlaps the surface of the first portion 11 of the FFC 5. Also, the third portions 13 and the fourth portions 14 of the N / 2 FFCs 3 do not overlap any portion of the N / 2 FFCs 4, and the third portions 23 and the fourth portions 24 of the N / 2 FFCs 4 do not overlap any portion of the N / 2 FFCs 3.

[0075] Thus, in the present embodiment, the N / 2 FFCs 3 and the N / 2 FFCs 4 overlap in such a manner that their non-shield surfaces (back surfaces) do not face each other. Thereby, it is possible to reduce the wiring-to-wiring interference. Also, by staggering the first overlap portions of the N / 2 FFCs 3 and the second overlap portions of the N / 2 FFCs 4, it is possible to reduce the thickness of the entire N FFCs 3, 4.

[0076] As Figure 17As shown, in a state where the surfaces of the first circuit substrates DA and DB (mounting surfaces of the first connectors KA1, KA2, KB1, and KB2) face the backlight BL side, and the surface of the second circuit substrate TC (mounting surfaces of the second connectors CB1, CB2, CA1, and CA2) faces the side opposite to the backlight BL, the first circuit substrates DA and DB and the second circuit substrate TC are connected via N FFCs 3 and 4. Therefore, in this embodiment, the same effect as in the first embodiment can be obtained. That is, even in a state where the surfaces of the first circuit substrates DA and DB face the backlight BL side, and the surface of the second circuit substrate TC faces the side opposite to the backlight BL (that is, the second connectors CB1, CB2, CA1, and CA2 are visible to the operator), the connection operation of the FFCs 3 and 4 can be performed, thereby suppressing a decrease in the operating efficiency when manufacturing the display device DS.

[0077] [Fifth embodiment]

[0078] Figure 18 and Figure 19 It is a plan view showing the structure of an FFC according to a fifth embodiment. Figure 20 It is a plan view showing the connection structure of the first circuit substrate and the second circuit substrate in the fifth embodiment. Figure 20 The display device DS includes: Figure 20 N (in this embodiment, N is an even number greater than 4, in the embodiment) arranged in parallel in the direction D2 when viewed from the back side of the paper. Figure 20first connectors KA1, KA2, KB1, KB2; N second connectors CB1, CB2, CA1, CA2 arranged side by side in the D2 direction as viewed from the backlight BL side; N / 2 FFCs 7 arranged side by side in the D2 direction as viewed from the backlight BL side; and N / 2 FFCs 8 arranged side by side in the D2 direction as viewed from the backlight BL side. As in the fourth embodiment, two of the N first connectors KA1, KA2, KB1, KB2, namely, the first connectors KA1, KA2, are provided to the first circuit board DA, and the other two first connectors KB1, KB2 are provided to the first circuit board DB. The N second connectors CB1, CB2, CA1, CA2 are all provided to the second circuit board TC. Each of the N / 2 FFCs 7 is substantially the same as the FFC 1 of the first embodiment except for the length of the second portion, and each of the N / 2 FFCs 8 is substantially the same as the FFC 2 of the first embodiment except for the length of the second portion. The constituent elements of the FFC 7 are labeled with the same reference numerals as the constituent elements of the FFC 1, and the constituent elements of the FFC 8 are labeled with the same reference numerals as the constituent elements of the FFC 2. The lengths of the second portions 12 of the N / 2 FFCs 7 are different from one another, and the lengths of the second portions 22 of the N / 2 FFCs 8 are different from one another. The surface of each FFC 7, 8 is a shielding surface, and the back surface is a non-shielding surface.

[0079] The N / 2 FFCs 7 and the N / 2 FFCs 8 are cross-connected to the N first connectors KA1, KA2, KB1, KB2 of the first circuit boards DA, DB and the N second connectors CB1, CB2, CA1, CA2 of the second circuit board TC in the following manner. That is, the second portion 12 of the N / 2 FFCs 7 is the FFC 7 of the nth (n is an integer of 1 or more and N / 2 or less) length, the first end 1X of which is connected to the nth first connector KAn of the N first connectors KA1, KA2, KB1, KB2 from the D2 direction side, and the second end 1Y of which is connected to the nth second connector CAn of the N second connectors CB1, CB2, CA1, CA2 from the other side (the right side in the drawing) of the D2 direction. Further, the second portion 22 of the N / 2 FFCs 8 is the FFC 8 of the nth length, the first end 2X of which is connected to the nth first connector KBn of the N first connectors KA1, KA2, KB1, KB2 from the other side of the D2 direction, and the second end 2Y of which is connected to the nth second connector CBn of the N second connectors CB1, CB2, CA1, CA2 from the D2 direction side.

[0080] As Figure 18 and Figure 20As shown, the second portion 12 of the N / 2 FFC7s is the mth (m is an integer greater than or equal to 2 and less than or equal to N / 2) longest FFC7, and the back surface of the second portion 12 thereof overlaps the (m-1)th FFC7 in such a manner that the second portion 12 of the N / 2 FFC7s faces the front surface of the second portion 12 of the (m-1)th longest FFC7. Figure 19 as well as Figure 20 As shown, the second part 22 of the mth longest FFC8 among N / 2 FFC8s has its second part 22 on the back side overlapping with the (m-1)th FFC8 in such a way that the second part 22 of the N / 2 FFC8s is opposite to the surface of the second part 22 of the (m-1)th longest FFC8.

[0081] like Figure 20 As shown, the back surface of the portion of second portion 12 of the N / 2 FFC7s (hereinafter referred to as "FFC9") that overlaps with first portion 11 (the first overlapping portion) of second portion 12 of the FFC7 is opposite the surface of first portion 21 of the FFC8 (hereinafter referred to as "FFC10") that has the longest second portion 22 of the FFC8s (hereinafter referred to as "FFC10"). FFC10 has the back surface of the portion of second portion 22 of the FFC10 that overlaps with first portion 21 (the second overlapping portion) facing the surface of first portion 11 of FFC9, so that the N / 2 FFC7s and the N / 2 FFC8s overlap. Furthermore, the third portion 13 and the fourth portion 14 of the N / 2 FFC7s do not overlap with any portion of the N / 2 FFC8s, and the third portion 23 and the fourth portion 24 of the N / 2 FFC8s do not overlap with any portion of the N / 2 FFC7s.

[0082] Thus, in this embodiment, N / 2 FFC7s and N / 2 FFC8s overlap in such a way that their non-shielded surfaces (back surfaces) do not face each other. Thus, interference between wiring can be reduced. In addition, by staggering the first overlapping parts of the N / 2 FFC7s and the second overlapping parts of the N / 2 FFC8s, the thickness of the N FFC7s and 8 as a whole can be reduced. In addition, the connection relationship between the multiple terminals of the first connectors KA1, KA2, KB1, and KB2 and the multiple terminals of the second connectors CB1, CB2, CA1, and CA2 is the same as the previous case where the surface of the first circuit substrate and the surface of the second circuit substrate are set to the same direction and the FFCs are not bent but directly connected. Therefore, there is no need to perform special processing such as left-right inversion of the image.

[0083] like Figure 20As shown, in a state where the surfaces of the first circuit substrates DA and DB (mounting surfaces of the first connectors KA1, KA2, KB1, and KB2) face the backlight BL side, and the surface of the second circuit substrate TC (mounting surfaces of the second connectors CB1, CB2, CA1, and CA2) faces the side opposite to the backlight BL, the first circuit substrates DA and DB and the second circuit substrate TC are connected via N FFCs 7 and 8. Therefore, in this embodiment, the same effect as in the first embodiment can be obtained. That is, even when the surfaces of the first circuit substrates DA and DB face the backlight BL side, and the surface of the second circuit substrate TC faces the side opposite to the backlight BL (that is, when the second connectors CB1, CB2, CA1, and CA2 are visible to the operator), the connection operation of the FFCs 7 and 8 can be performed, thereby suppressing a decrease in the operating efficiency when manufacturing the display device DS.

[0084] The above embodiments are for illustration and description purposes only and are not intended to be limiting. Based on these illustrations and descriptions, it will be apparent to those skilled in the art that various modifications can be made.

[0085] For example, in the above embodiments, the FFC includes four parts (first part 11, 21, second part 12, 22, third part 13, 23, and fourth part 14, 24) as an example for explanation. However, in each embodiment, the FFC may include other parts in addition to the above four parts. For example, the part from a certain position on the one end side to the first bending position 1F, 2F may be set as the first part 11, 21, and the FFC may include other parts between the one end and the certain position. In addition, the part from the third bending position 1T, 2T to a certain position on the other end side may be set as the fourth part 14, 24, and the FFC may include other parts between the certain position and the other end.

[0086] Description of Reference Numerals

[0087] 1-10: FFC (Flexible flat cable)

[0088] DS: Display Device

[0089] AK: Active matrix substrate

[0090] CF: Color filter substrate

[0091] BL: Backlight

[0092] DP: Display Panel

[0093] DA, DB: First circuit substrate

[0094] TC: Second circuit substrate

[0095] KA, KB: first connector

[0096] CA, CB: second connector

[0097] D2: second direction

Claims

1. A display device, characterized in that: It has: Display panel; a backlight that irradiates light toward the display panel; at least one first circuit substrate having at least one first connector and arranged near the backlight in such a manner that a surface on which the at least one first connector is mounted faces the backlight side; a second circuit substrate having at least one second connector, the second circuit substrate being arranged near the backlight with its back surface opposite to the surface on which the at least one second connector is mounted facing the backlight side, and connected to the display panel via the first circuit substrate; as well as at least one FFC connecting the first circuit substrate and the second circuit substrate, The at least one FFC is bent at multiple bending positions in such a manner that one of the surface and the back surface at its first end faces the backlight side and the other of the surface and the back surface at its second end faces the backlight side, the first end is connected to the first connector, and the second end is connected to the second connector.

2. The display device according to claim 1, wherein The plurality of bending positions include a first bending position, a second bending position and a third bending position, The at least one FFC includes: a first portion extending from one end or a position on the side of one end to the first bending position; a second portion extending from the first bending position to the second bending position; a third portion extending from the second bending position to the third bending position; and a fourth portion extending from the third bending position to the other end or a position on the side of the other end. The one end is the first end, and the other end is the second end, or the one end is the second end, and the other end is the first end, The at least one FFC is bent at the multiple bending positions in such a manner that the respective surfaces of the first and third parts and the respective back surfaces of the second and fourth parts face the backlight side, or the respective back surfaces of the first and third parts and the respective surfaces of the second and fourth parts face the backlight side.

3. The display device according to claim 2, wherein: A plurality of wirings extending from the first end to the second end are arranged side by side on the at least one FFC, The direction in which the plurality of wirings extend is set as a first direction, When the end portion of the first portion on the second portion side is viewed from above, the first direction at the end portion is orthogonal to the first direction at the end portion of the second portion on the first portion side. When the end portion of the second portion on the third portion side is viewed from above, the first direction at the end portion is orthogonal to the first direction at the end portion of the third portion on the second portion side. In a plan view of an end portion of the third portion on the fourth portion side, the first direction at the end portion is opposite to and parallel to the first direction at an end portion of the fourth portion on the third portion side.

4. The display device according to claim 2, wherein: The at least one FFC is bent at the first bending position in such a manner that a portion of the surface of the first portion is opposite to a portion of the surface of the second portion, bending at the second bending position in such a manner that another portion of the surface of the second portion is opposed to a portion of the surface of the third portion, The third portion is bent at the third bending position so that a back surface of the third portion and a portion of a back surface of the fourth portion face each other.

5. The display device according to claim 2, wherein The first portion, the second portion, and the third portion are each in a trapezoidal shape. The fourth portion is in the shape of a rectangle.

6. The display device according to claim 2, wherein: A plurality of wirings extending from the first end to the second end are arranged side by side on the at least one FFC, When the direction in which the plurality of wirings extend is set as a first direction, When the end portion of the first portion on the second portion side is viewed from above, the first direction at the end portion is orthogonal to the first direction at the end portion of the second portion on the first portion side. When the end portion of the second portion on the third portion side is viewed from above, the first direction at the end portion is parallel to and opposite to the first direction at the end portion of the third portion on the second portion side. In a plan view of an end portion of the third portion on the fourth portion side, the first direction at the end portion is orthogonal to the first direction at an end portion of the fourth portion on the third portion side.

7. The display device according to claim 2, wherein: The at least one FFC is bent at the first bending position in such a manner that a portion of the surface of the first portion is opposite to a portion of the surface of the second portion, The second portion is bent at the second bending position so that a portion of the back surface of the second portion faces the back surface of the third portion. The third portion is bent at the third bending position such that a portion of the surface of the third portion faces a portion of the surface of the fourth portion.

8. The display device according to claim 2, wherein: Each of the first portion, the second portion, the third portion, and the fourth portion has a trapezoidal shape.

9. The display device according to any one of claims 2 to 8, wherein: The at least one first connector includes two first connectors, The at least one second connector includes two second connectors, The at least one FFC includes two FFCs, a first FFC and a second FFC, The first end of the first FFC is connected to one of the two first connectors. The second end of the first FFC is connected to one of the two second connectors. The first end of the second FFC is connected to the other of the two first connectors. The second end of the second FFC is connected to the other of the two second connectors. The first FFC and the second FFC are arranged crosswise.

10. The display device according to claim 9, wherein The first FFC and the second FFC overlap in such a manner that the back side of the second part of the first FFC that overlaps with the first part of the first FFC is opposite to the surface of the first part of the second FFC, and the back side of the second part of the second FFC that overlaps with the first part of the second FFC is opposite to the surface of the first part of the first FFC.

11. The display device according to claim 10, wherein: The third portion and the fourth portion of the first FFC do not overlap with any portion of the second FFC, and the third portion and the fourth portion of the second FFC do not overlap with any portion of the first FFC.

12. The display device according to any one of claims 2 to 5, wherein: The at least one first connector includes N first connectors arranged in parallel in the second direction when viewed from the backlight side, where N is an integer greater than or equal to 2. The at least one second connector includes N second connectors arranged in parallel in the second direction when viewed from the backlight side. The at least one FFC includes N FFCs arranged in parallel in the second direction when viewed from the backlight side, The nth FFC from one side in the second direction among the N FFCs has its first end connected to the nth first connector from the one side in the second direction among the N first connectors, and its second end connected to the nth second connector from the one side in the second direction among the N second connectors, where n is an integer greater than or equal to 1 and less than or equal to N. Each of the N FFCs is arranged so that the first portion is closer to the one side than the fourth portion. The mth FFC from the one side of the second direction among the N FFCs overlaps with the (m-1)th FFC in such a way that the back side of the part of its second part overlapping with its first part is opposite to the surface of the second part of the (m-1)th FFC from the one side of the second direction among the N FFCs, where m is an integer greater than 2 and less than N.

13. The display device according to any one of claims 2 to 5, characterized in that The at least one first connector includes N first connectors arranged in parallel in the second direction when viewed from the backlight side, where N is an even number greater than 4; The at least one second connector includes N second connectors arranged in parallel in the second direction when viewed from the backlight side. The at least one FFC comprises: N / 2 third FFCs are arranged in parallel in the second direction when viewed from the backlight side; and N / 2 fourth FFCs are arranged in parallel in the second direction when viewed from the backlight side, The N / 2 third FFCs and the N / 2 fourth FFCs are of the same shape, The first end of the nth third FFC from the one side in the second direction among the N / 2 third FFCs is connected to the nth first connector from the one side in the second direction among the N first connectors, and the second end of the nth third FFC is connected to the (n+N / 2)th second connector from the one side in the second direction among the N second connectors, where n is an integer greater than or equal to 1 and less than or equal to N / 2. The first end of the nth fourth FFC from the one side in the second direction among the N / 2 fourth FFCs is connected to the (n+N / 2)th first connector from the one side in the second direction among the N first connectors, and the second end of the fourth FFC is connected to the nth second connector from the one side in the second direction among the N second connectors. The third FFC and the fourth FFC are cross-configured.

14. The display device according to claim 13, wherein: The first portion of each of the N / 2 third FFCs and the N / 2 fourth FFCs is arranged closer to the one side than the fourth portion. The mth third FFC from the one side in the second direction among the N / 2 third FFCs overlaps with the (m-1)th third FFC in such a manner that the back surface of the portion of the second portion of the third FFC that overlaps with the first portion of the second portion faces the front surface of the second portion of the (m-1)th third FFC from the one side in the second direction among the N / 2 third FFCs, where m is an integer greater than or equal to 2 and less than or equal to N / 2. The mth fourth FFC from the one side of the second direction among the N / 2 fourth FFCs overlaps with the (m-1)th fourth FFC in such a manner that the back side of the portion of its second portion overlapping with its first portion is opposite to the surface of the second portion of the (m-1)th fourth FFC from the one side of the second direction among the N / 2 fourth FFCs.

15. The display device according to claim 14, wherein: The fifth FFC among the N / 2 third FFCs, which is closest to the side of the second direction, has the back side of the part of its second portion overlapping with its first portion opposite to the surface of the first portion of the sixth FFC among the N / 2 fourth FFCs, which is closest to the side of the second direction. The sixth FFC overlaps the third FFC and the fourth FFC in such a way that the back side of the part of its second portion overlapping with its first portion opposite to the surface of the first portion of the fifth FFC.

16. The display device according to any one of claims 2 to 5, characterized in that The at least one first connector includes N first connectors arranged in parallel in the second direction when viewed from the backlight side, where N is an even number greater than 4; The at least one second connector includes N second connectors arranged in parallel in the second direction when viewed from the backlight side. The at least one FFC comprises: N / 2 seventh FFCs are arranged in parallel in the second direction when viewed from the backlight side; and N / 2 eighth FFCs are arranged in parallel in the second direction when viewed from the backlight side. The lengths of the second parts of the N / 2 seventh FFCs are different. The lengths of the second parts of the N / 2 eighth FFCs are different. The second portion of the N / 2 seventh FFCs is an n-th longest seventh FFC, the first end of which is connected to the n-th first connector from one side of the N first connectors in the second direction, and the second end of which is connected to the n-th second connector from the other side of the N second connectors in the second direction, where n is an integer greater than or equal to 1 and less than or equal to N / 2. The nth longest eighth FFC in the second part of the N / 2 eighth FFCs has its first end connected to the nth first connector from the other side of the second direction among the N first connectors, and its second end connected to the nth second connector from the one side of the second direction among the N second connectors. The seventh FFC and the eighth FFC are cross-configured.

17. The display device according to claim 16, wherein: The second portion of the N / 2 seventh FFCs is the m-th longest seventh FFC, and the back surface of the second portion of the N / 2 seventh FFCs is opposite to the front surface of the second portion of the (m-1)-th longest seventh FFC, so that the second portion overlaps with the (m-1)-th longest seventh FFC, where m is an integer greater than or equal to 2 and less than or equal to N / 2. The second part of the N / 2 eighth FFCs is the mth longest eighth FFC, and overlaps with the (m-1)th longest eighth FFC in such a way that the back side of its second part is opposite to the surface of the second part of the eighth FFC that is the (m-1)th longest among the N / 2 eighth FFCs.

18. The display device according to claim 17, wherein: The ninth FFC whose second part is the longest among the N / 2 seventh FFCs overlaps the seventh FFC and the eighth FFC in such a manner that the back side of the portion of its second part overlapping with its first part is opposite to the surface of the first part of the tenth FFC whose second part is the longest among the N / 2 eighth FFCs, and the back side of the portion of the second part of the tenth FFC overlapping with its first part is opposite to the surface of the first part of the ninth FFC.

19. The display device according to any one of claims 1 to 8, wherein: The surface of the FFC is a shielding surface, and the back surface of the FFC is a non-shielding surface.

20. The display device according to any one of claims 1 to 8, wherein The display panel includes an active matrix substrate, a color filter substrate, and a liquid crystal layer sandwiched between the active matrix substrate and the color filter substrate. The color filter substrate is arranged closer to the backlight side than the active matrix substrate. The first circuit substrate is connected to an end portion of the backlight-side surface of the active matrix substrate via a flexible wiring substrate.

Images