WO2018212089A1 - Method for manufacturing display module and method for inspecting display module - Google Patents

Abstract

This method for manufacturing a display module is a method for manufacturing a display module (1) that is provided with: a display panel (2) that includes a terminal section (2D) at an end portion (2A1) thereof; a lighting device (3), which is disposed on the rear surface (2b) side of the display panel (2), and which supplies light to the display panel (2); and a flexible wiring board (4) that is bent to warp outward so that one end (41) is fixed to the end portion (2A1) of the display panel (2) by being electrically connected to the terminal section (2D), and the other end (42) is disposed on the rear surface (3b) side of the lighting device (3). The method is provided with a detection step for detecting a failure of the flexible wiring board (4) by supplying a drive signal to the display panel (2) via the flexible wiring board (4) in a state wherein a base portion (411) of the flexible wiring board (4), said base portion being adjacent to the one end (41), is lifted in the direction to be away from the display panel (2).

Description

Display module manufacturing method and display module inspection method

The present invention relates to a display module manufacturing method and a display module inspection method.

As shown in Patent Document 1, a liquid crystal display module used for a liquid crystal display device is connected to a liquid crystal display panel, a backlight device disposed on the back side of the liquid crystal display panel, and an end of the liquid crystal display panel. A flexible wiring board. A terminal portion is formed at an end portion of the liquid crystal display panel, and one end portion of the flexible wiring board is connected to be electrically connected to the terminal portion. In addition, a control board made of a printed board is connected to the other end of the flexible wiring board.

Since the control board is installed on the back side of the backlight device, the flexible wiring board is bent so as to bend outward. The flexible wiring board is set to be thin in order to bend easily.

JP 2005-316238 A

(Problems to be solved by the invention)
In the manufacturing process of the liquid crystal display module, after the flexible wiring board is connected to the liquid crystal display panel and the control board, the liquid crystal display panel with the flexible wiring board is finally formed until the liquid crystal display module is formed. In contrast, a plurality of processing operations are performed. During such a processing operation, if the flexible wiring board is bent in the reverse direction by mistake, the wiring portion of the flexible wiring board may be cracked. If the wiring portion is cracked in this way, the liquid crystal display module normally does not operate normally.

However, even if there is a crack in the wiring part, the flexible wiring board bends in the normal direction, the divided wiring parts approach each other, and the crack is temporarily repaired. During the continuity test, the liquid crystal display module may be driven normally. In such a liquid crystal display module, there is a possibility that after shipment, the crack of the wiring part further proceeds due to the influence of vibration and the influence of temperature or humidity, and finally a display defect may occur in the liquid crystal display module.

An object of the present invention is to provide a display module manufacturing method in which the occurrence of display defects due to defects in wiring portions of a flexible wiring board is suppressed.

(Means for solving the problem)
A display module manufacturing method according to the present invention includes a display panel including a terminal portion at an end portion, a lighting device disposed on the back side of the display panel to supply light to the display panel, and one end electrically connected to the terminal portion. Of a display module comprising: a flexible wiring board that is fixed to the end of the display panel in a connected manner and bent outwardly so that the other end is disposed on the back side of the lighting device In the method, a driving signal is supplied to the display panel through the flexible wiring board in a state where a base portion adjacent to the one end of the flexible wiring board is lifted away from the display panel. And a detecting step of detecting a defect of the flexible wiring board.

The display module inspection method according to the present invention includes a display panel including a terminal portion at an end portion, a lighting device disposed on the back side of the display panel and supplying light to the display panel, and one end of the terminal portion. And a flexible wiring board that is fixed to the end portion of the display panel so as to be electrically connected to the display panel and is bent outwardly so that the other end is disposed on the back side of the lighting device. In the inspection method, a base portion adjacent to the one end of the flexible wiring board is lifted in a direction away from the display panel, and a drive signal is supplied to the display panel through the flexible board. And a detecting step of detecting a defect of the flexible wiring board.

(The invention's effect)
ADVANTAGE OF THE INVENTION According to this invention, the manufacturing method of a display module etc. with which generation | occurrence | production of the display defect resulting from the defect of the wiring part of a flexible wiring board was suppressed can be provided.

Explanatory drawing which shows schematic structure of the liquid crystal display module which concerns on Embodiment 1 of this invention. Sectional drawing which represented typically the structure which the edge part of a flexible wiring board and the terminal part of a liquid crystal display panel connect Explanatory drawing which shows the state which the crack generate | occur | produced in the wiring part of the base part of a flexible wiring board Explanatory drawing schematically showing the device used in the inspection method of the liquid crystal display module Explanatory drawing which shows the state which pressed the flexible wiring board with the 1st press member. Explanatory drawing which shows the state which pressed the flexible wiring board with the 2nd press member with the 1st press member. Explanatory drawing which shows the state which pressed the flexible wiring board only with the 2nd press member.

<Embodiment 1>
A method for manufacturing a liquid crystal display module according to Embodiment 1 of the present invention will be described with reference to FIGS. FIG. 1 is a side view showing a schematic configuration of a liquid crystal display module 1 according to Embodiment 1 of the present invention. Here, first, the configuration of the liquid crystal display module 1 will be described.

As shown in FIG. 1, a liquid crystal display module (an example of a display module) 1 mainly includes a liquid crystal display panel (an example of a display panel) 2, an illumination device (backlight device) 3, and a flexible wiring board 4. I have. The liquid crystal display module 1 further includes a control substrate 5.

The liquid crystal display panel 2 is a plate-like member having a substantially rectangular shape in plan view, and mainly includes a pair of transparent substrates and a liquid crystal layer sealed in a sandwiched manner therebetween. Become. Of the pair of substrates, one substrate is the array substrate 2A, and is composed of a transparent glass substrate on which TFTs (Thin-Film-Transistors) and pixel electrodes as switching elements are arranged in a matrix. . The other substrate is a color filter (hereinafter referred to as CF) substrate 2B, in which color filters made of red, green, and blue are arranged in a matrix on a transparent glass substrate. .

In FIG. 1, the array substrate 2A is disposed on the lower side, and the CF substrate 2B is disposed on the upper side. Further, the display surface 2a of the liquid crystal display panel 2 is disposed on the upper side of FIG. 1, and the back surface 2b of the liquid crystal display panel 2 is disposed on the lower side.

The array substrate 2A is larger than the CF substrate 2B, and one end 2A1 of the array substrate 2A protrudes outward from one end 2B1 of the CF substrate 2B, so that the array substrate 2A and the CF substrate 2B Are stacked. An end 2A1 of the array substrate 2A projecting outward (hereinafter sometimes referred to as “projected end 2A1”) is in a non-display area of the liquid crystal display panel 2, and the liquid crystal display panel is disposed on the surface 2Aa thereof. A driver 2 </ b> C for driving each of the two pixels (sub-pixels) is mounted using COG (Chip On Glass) technology. The driver 2C is formed of a chip-like IC (Integrated Circuit). One end 41 of the flexible wiring board 4 is connected to the surface 2Aa of the protruding end 2A1 of the array substrate 2A. Details of the structure in which the end 41 is connected to the overhanging end 2A1 will be described later.

The lighting device 3 is arranged on the back surface 2b side of the liquid crystal display panel 3, and irradiates light toward the back surface 2b of the liquid crystal display panel 3. The illumination device 3 is thicker than the liquid crystal display panel 2 and has a substantially plate shape larger than the liquid crystal display panel 2 in plan view. The light emission surface 3a of the illuminating device 3 is arranged on the upper side of FIG. 1, and the back surface 3b of the illuminating device 3 is arranged on the lower side. In addition, one end portion 31 of the lighting device 3 projects outward from the projecting end portion 2A1 of the liquid crystal display panel 2.

The flexible wiring board 4 is a thin wiring board having flexibility for electrically connecting the liquid crystal display panel 2 and the control board 5 and is formed of a so-called flexible printed circuit. The flexible wiring board 4 has a band shape as a whole, and is bent so as to bend outward as shown in FIG. One end portion 41 of the flexible wiring board 4 is a portion connected to an overhang end portion 2A1 (more specifically, a terminal portion 2D described later) of the liquid crystal display panel 2, and the other end portion 42 is This is a portion connected to the control board 5. In the flexible wiring board 4, a portion adjacent to one end 41 is referred to as a base (first base) 411, and a portion adjacent to the other end 42 is referred to as a base (second base) 421.

FIG. 2 is a cross-sectional view schematically showing a configuration in which the end portion 41 of the flexible wiring board 4 and the terminal portion 2D of the liquid crystal display panel 2 are connected. As shown in FIG. 2, a terminal portion 2D is provided on the protruding end portion 2A1 of the array substrate 2A of the liquid crystal display panel 2. The terminal portion 2D is made of a metal pad-like member and is electrically connected to the driver 2C and the like. The terminal portion 2D is disposed outside the driver 2C on the surface 2Aa of the overhang end portion 2A1. A plurality of terminal portions 2D are provided on the overhang end portion 2A1.

The flexible wiring board 4 mainly includes a base material layer 4A, a wiring portion 4B, and a coating layer 4C. The base material layer 4A is a film-like member having an insulating property made of polyimide resin or the like. In the case of the present embodiment, the base material layer 4A is set to have a thickness larger than that of the wiring portion 4B and the covering layer 4C. A wiring portion 4B made of a metal foil such as a copper foil is formed in a pattern on one surface of the base material layer 4A. The covering layer 4C is made of a resin film having insulating properties, and is laminated so as to be in close contact with the base material layer 4A so as to cover the wiring portion 4B. As shown in FIG. 2, the covering layer 4 </ b> C is formed so that the end portion 41 of the flexible wiring board fixed to the protruding end portion 2 </ b> A <b> 1 of the liquid crystal display panel 2 and the wiring portion 4 </ b> B at the base portion 411 are exposed. ing. The wiring part 4B at the end part 41 of the flexible wiring board 4 is a terminal part (FPC terminal part), and is electrically connected to the terminal part 2D on the overhanging end part 2A1 through an anisotropic conductive film (not shown). And mechanically connected.

Also on the other end 42 side of the flexible wiring board 4, the wiring part 4 </ b> B is not covered with the coating layer 4 </ b> C, and is a terminal part (FPC terminal part) connected to the terminal part of the control board 5. The control board 5 is a printed board on which a controller IC is mounted, and performs display control of the liquid crystal display panel 2 via the flexible wiring board 4 and the driver 2C.

As shown in FIG. 1, the protective layer 6 is formed on the end 31 of the lighting device 3, and the inner surface side of the curved flexible wiring board 4 comes into contact with the end 31 of the lighting device 3. In addition, the flexible wiring board 4 is prevented from being damaged. The protective layer 6 consists of an adhesive sheet provided with a porous layer.

Here, with reference to FIG. 3 and the like, the reason why the crack X occurs in the wiring part 4B in the base part 411 of the flexible wiring board 4 in the manufacturing process of the liquid crystal display module 1 will be described. FIG. 3 is an explanatory diagram showing a state in which a crack X has occurred in the wiring portion 4B of the base portion 411 of the flexible wiring board 4. In the manufacturing process of the liquid crystal display module 1, one end portion 41 of the flexible wiring substrate 4 is connected to the terminal portion 2 </ b> D of the liquid crystal display panel 2, and the other end portion 42 is connected to the terminal portion of the control substrate 5. . The flexible wiring board 4 is attached to the liquid crystal display panel 2 in such a manner that the base layer 4A is disposed on the outer side and the covering layer 4C is disposed on the inner side. As shown in FIG. 1, the flexible wiring board 4 is finally bent so as to bend in a normal direction (outward) in order to install the control board 5 on the back surface 3 b side of the lighting device 3.

Until the control board 5 is finally installed, the flexible wiring board 4 has one end 41 fixed on the protruding end 2A1 of the liquid crystal display panel 2, but the other end 42 side is not It is in a state where it can move freely without being restrained. The liquid crystal display panel 2 is subjected to a plurality of manufacturing processes with the flexible wiring board 4 in such a state. Therefore, in the manufacturing process, the end portion 42 side of the flexible wiring board 4 is erroneously moved away from the lighting device 3 side (to the liquid crystal display panel 2 side), and the flexible wiring board 4 is opposite to the normal direction. It may be bent in the direction. At that time, the flexible wiring board 4 is warped outward, and a force is applied to the wiring portion 4B on the base material layer 4A so as to be pulled from both sides in the longitudinal direction of the flexible wiring board 4.

Of the flexible wiring board 4, the base 411 is a part that becomes a fulcrum when the flexible wiring board 4 warps outward, and stress is particularly likely to concentrate. Further, the base portion 411 is also a portion where the wiring portion 4B is not covered with the covering layer 4C, and has a lower rigidity than the portion covered with the covering layer 4C. Therefore, as shown in FIG. 2, when the flexible wiring board 4 warps outward, a crack X may occur in the wiring part 4 </ b> B of the base part 411.

In addition, the base part 421 adjacent to the other end part 42 of the flexible wiring board 4 is usually covered with the covering layer 4C, but the flexible wiring board 4 usually warps outward, like the base part 411. Therefore, it can be said that cracks are unlikely to occur at the base 421.

By the way, in the base part 411 of the flexible wiring board 4, even if the crack X occurs in the wiring part 4B, the flexible wiring board 4 is finally bent in a normal direction, so that the divided wiring parts 4B are mutually connected. As a result, the crack X may be temporarily repaired and the conduction of the wiring portion 4B may be secured. Therefore, in order to reliably detect such defects as cracks X and the like, in the method of manufacturing the liquid crystal display module 1 of the present embodiment, the continuity inspection of the flexible wiring board 4 is performed. Hereinafter, the continuity test of the flexible wiring board 4 (inspection method of the liquid crystal display module 1) will be described with reference to FIGS.

FIG. 4 is an explanatory view schematically showing an apparatus used in the inspection method of the liquid crystal display module 1. As shown in FIG. 4, in the inspection method for the liquid crystal display module 1, the base 7, the first pressing member 81, the second pressing member 82, and the signal generator 9 are used.

The table 7 is for mounting the liquid crystal display module 1 to be inspected, and includes a flat plate-shaped mounting portion 71 on which the liquid crystal display module 1 is mounted, and a standing wall portion 72 that stands from the end of the mounting portion 71. It has. The liquid crystal display module 1 is installed in a horizontal state on the table 7 (mounting unit 71) such that the back surface 3b of the lighting device 3 faces the surface of the mounting unit 71. In the case of the present embodiment, the control board 5 is arranged on the outside of the placement portion 71. Further, the standing wall portion 72 is erected on the mounting portion 71 so as to face the end portion 32 on the opposite side of the end portion 31 of the lighting device 3 projecting outward.

The first pressing member 81 and the second pressing member 82 press the flexible wiring board 4 included in the liquid crystal display module 1 in a predetermined direction, and lift the base 411 of the flexible wiring board 4 in a direction away from the liquid crystal display panel 2. Means. The first pressing member 81 and the second pressing member 82 are made of a material having both moderate hardness and moderate softness such as a porous resin material (for example, resin foam, resin sponge). When the first pressing member 81 and the second pressing member 82 are formed of such a material, the flexible wiring board 4 can be reliably pressed in a predetermined direction, and the flexible wiring board 4 can be damaged. It is suppressed. The first pressing member 81 is a member that moves in the vertical direction (vertical direction) to press the flexible wiring board 4 in a predetermined direction, and the second pressing member 82 moves in the left-right direction (horizontal direction). It is a member that presses the flexible wiring board 4 in a predetermined direction.

The signal generator 9 is a device that supplies a signal (driving signal) for driving the liquid crystal display module 1 to be lit, and is electrically connected to the control board 5 via a cable 91.

Hereinafter, the specific procedure of the continuity inspection (inspection method of the liquid crystal display module 1) of the flexible wiring board 4 provided in the liquid crystal display module 1 will be described. First, as shown in FIG. 4, the liquid crystal display module 1 to be inspected is installed on the base 7. In the liquid crystal display module 1 on the table 7, the flexible wiring board 4 is bent so as to be bent outward. Thereafter, the signal generator 9 supplies a predetermined signal to the liquid crystal display module 1 to drive the liquid crystal display module 1 (the liquid crystal display panel 2 and the illumination device 3) to light.

Next, in the liquid crystal display module 1 in the lighting-driven state, as shown in FIG. 5, the base 421 side is pressed from the back surface 3 b side of the lighting device 3 by the first pressing member 81, and the flexible wiring board 4 is The liquid crystal display panel 2 is lifted to some extent. At that time, the flexible wiring substrate 4 on the base portion 421 side is pressed against the back surface 3 b side of the end portion 31 of the lighting device 3. In addition, since the protective layer 6 is affixed on the surface of the edge part 31, the contact of the edge part 31 and the flexible wiring board 4 is eased.

As shown in FIG. 5, when the flexible wiring board 4 is pressed only by the first pressing member 81, the base 411 of the flexible wiring board is sufficiently lifted in the direction away from the liquid crystal display panel 2 (upward in FIG. 5). It is not in the state that was done. This is because the flexible wiring board 4 escapes and moves outward (in a direction away from the lighting device 3 and the like). Therefore, the vicinity of the base portion 411 is not warped outward, and in this state, even if a crack X occurs in the wiring portion 4B of the flexible wiring board 4, conduction of the wiring portion 4B is ensured. There is a possibility that. Therefore, as will be described later, the flexible wiring board 4 is further pressed using the second pressing member 82.

As described above, in a state where the flexible wiring board 4 is pressed by the first pressing member 81, the flexible wiring board 4 is further moved closer to the end 31 of the lighting device 3 as shown in FIG. 6. The second pressing member 82 is pressed from the outside toward the inside. The pressing by the second pressing member 82 is performed on a portion of the flexible wiring board 4 that is above the portion where the first pressing member 81 is in contact and that faces the end portion 31 of the lighting device 3. . Thus, in addition to the first pressing member 81, the second pressing member 82 simultaneously presses the flexible wiring board 4, so that the base 411 of the flexible wiring board 4 disposed on the upper side becomes the liquid crystal display panel 2. Can be lifted away. As a result, a portion extending from the base portion 411 toward the end portion 42 side is inclined so as to be generally raised (a state of warping outward), and at least the wiring portion 4B in the base portion 411 is extended. For this reason, if there is a crack X in the wiring part 4B in the base part 411, the divided wiring parts 4B are separated from each other, so that a conduction failure occurs reliably in the wiring part 4B, and the liquid crystal display module 1 A lighting failure occurs in (the liquid crystal display panel 2, the illumination device 3). Specifically, the liquid crystal display panel 2 is not lit or a portion where a predetermined color is not displayed occurs. In this way, by using the first pressing member 81 and the second pressing member 82 to lift the base 411, defects (cracks, disconnection) of the flexible wiring board 4 can be reliably detected visually.

As shown in FIG. 7, if the flexible wiring board 4 (location facing the end portion 31 of the lighting device 3) is pressed from the outside to the inside only with the second pressing member 82, the flexible wiring board 4 is The upper portion and the lower portion are divided into a small curved state, and the vicinity of the base portion 411 cannot be sufficiently warped outward.

<Other embodiments>
The present invention is not limited to the embodiments described with reference to the above description and drawings. For example, the following embodiments are also included in the technical scope of the present invention.
(1) In the above embodiment, the liquid crystal display module is exemplified as the display module. However, the present invention may be applied to other display modules as long as the object of the present invention is not impaired.
(2) In the above embodiment, the liquid crystal display panel is exemplified as the display panel. However, the present invention may be applied to other display panels as long as the object of the present invention is not impaired.
(3) In the above-described embodiment, the end 31 of the lighting device 3 protrudes outside the end 2A1 of the liquid crystal display panel 2, but the present invention is not limited to this, and the end 2A1 of the liquid crystal display panel 2 And the end 31 of the illuminating device 3 may be at the same position, or conversely, the end 2A1 of the liquid crystal display panel 2 projects outward from the end 31 of the illuminating device 3. May be. Even in such a case, by using the first pressing member 81 and the second pressing member 82 to press the flexible wiring board 4 in a predetermined direction, the base 411 is lifted upward (warped outward). be able to.

DESCRIPTION OF SYMBOLS 1 ... Liquid crystal display module (display module), 2 ... Liquid crystal display panel (display panel), 3 ... Illuminating device, 4 ... Flexible wiring board, 4A ... Base material layer, 4B ... Wiring part, 4C ... Covering layer, 41 ... One End (one end), 411 ... base, 5 ... control board, 6 ... protective layer, 7 ... stand, 81 ... first pressing member, 82 ... second pressing member, 9 ... signal generator, 91 ... cable, X …crack

Claims (7)

A display panel including a terminal portion at an end; a lighting device disposed on a back side of the display panel for supplying light to the display panel; and the one end of the display panel electrically connected to the terminal portion. A flexible wiring board that is fixed to the end and bent outwardly so that the other end is disposed on the back side of the lighting device, and a method for manufacturing a display module,
The flexible wiring board is configured to supply a drive signal to the display panel through the flexible wiring board in a state in which a base portion adjacent to the one end is lifted away from the display panel. A method for manufacturing a display module, comprising a detection step for detecting a malfunction of the display module. In the detection step, the flexible wiring board is pressed from the back side of the lighting device, and further, the flexible wiring board is moved from the outside to the inside so that the flexible wiring board in that state approaches the end of the lighting device. The method of manufacturing a display module according to claim 1, wherein the base is lifted in a direction away from the display panel by being pressed toward the display. 3. The method for manufacturing a display module according to claim 2, wherein the end of the lighting device projects outward from the end of the display panel. 4. The method of manufacturing a display module according to claim 2, wherein a porous resin material is used for pressing the flexible wiring board in the detection step. The flexible wiring board includes a film-like base material layer, a pattern-like wiring portion formed on the base material layer, the one end fixed to the end portion of the display panel, and the wiring portion in the base portion. The manufacturing method of the display module as described in any one of Claims 1-4 which has a coating layer formed on the said base material layer in the form which covers the said wiring part so that may be exposed. 6. The method of manufacturing a display module according to claim 5, wherein the flexible wiring board has the covering layer disposed on the inner side and the base material layer disposed on the outer side. A display panel including a terminal portion at an end; a lighting device disposed on a back side of the display panel for supplying light to the display panel; and the one end of the display panel electrically connected to the terminal portion. A display module inspection method comprising: a flexible wiring board that is fixed to an end portion and bent in such a manner that the other end is bent outwardly so as to be arranged on the back side of the lighting device,
A driving signal is supplied to the display panel through the flexible wiring board in a state where a base portion adjacent to the one end of the flexible wiring board is lifted away from the display panel. A display module inspection method comprising a detection step of detecting a defect.

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