JP2007292826A - Liquid crystal module - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a display module having high reliability by suppressing peeling of a bent flexible substrate. <P>SOLUTION: The liquid crystal display module 100 is provided with: an FPC (Flexible Printed Circuit) 103; a liquid crystal display panel 101 connected to one end of the FPC 103; a light source 106 mounted on a light source mounting part Q of a light source mounting surface P of the FPC 103; and a backlight unit 102 disposed on the back surface side of the liquid crystal display panel 101 and housing the light source 106. In a first bent part 104, the FPC 103 is bent to the back surface side of the backlight unit 102, then, the light source mounting surface P of the FPC 103 is disposed on the side opposite from the backlight unit. In a second bent part 105, the light source mounting surface P of the FPC 103 is bent to the backlight unit 102 side and the light source 106 is housed in the backlight unit 102. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a liquid crystal module, and more particularly, to a liquid crystal module including a flexible substrate.

  In general, a flat panel display such as a liquid crystal display device or an organic EL display device uses a flexible printed circuit (FPC) for the purpose of miniaturization. In recent years, in order to reduce the thickness of a liquid crystal display device, a light emitting diode for backlight (hereinafter abbreviated as LED) mounted on a flexible substrate has been developed (for example, see Patent Document 1).

  FIG. 6 shows a configuration of a conventional liquid crystal display device. As shown in FIG. 6, the liquid crystal display device 10 includes a liquid crystal display panel 11, a backlight unit 12, an FPC 13, and the like. The FPC 13 is physically and electrically connected to one side of the liquid crystal display panel 11 by an anisotropic conductive film (ACF).

  A backlight unit 12 is disposed on the back side of the liquid crystal display panel 11. The FPC 13 is bent in a U-shape on the backlight unit 12 side of the liquid crystal display panel 11 and is fixed to the non-viewing side of the backlight unit 12 with a double-sided tape 14.

A light source 15 such as an LED is disposed on the FPC 13. The light source 15 is arranged along the light incident end face of the light guide plate provided in the backlight unit 12 by bending the FPC 13. By mounting the light source 15 on the flexible substrate 13 as described above, it is not necessary to secure a separate installation space for the light source 15, and the apparatus is reduced in thickness and size.
JP 2002-156648 A

  By the way, the liquid crystal display device is required to have high reliability, and it is necessary to maintain sufficient quality even in a high temperature and high humidity environment. However, there is a disadvantage when the FPC 13 is bent into a U shape and bonded to the backlight unit 12 with the double-sided tape 14 as described above. That is, there is a problem that the adhesive ability of the double-sided tape 14 fixing the FPC 13 is lowered, and the FPC 13 is peeled and bent by the elastic restoring force of the conductive thin film and the insulating thin film constituting the FPC 13.

  As described above, when the light source 15 is mounted on the FPC 13, the FPC 13 is peeled off, so that the light source 15 is displaced from the light incident end face of the light guide plate, and there is a problem that the luminance is lowered. Further, if the optical axis of the light source 15 is deviated, light emission unevenness may occur.

  The present invention has been made against the background of the above circumstances, and an object of the present invention is to provide a high-quality liquid crystal module that prevents the positional deviation of the light source.

  A liquid crystal module according to a first aspect of the present invention is mounted on a flexible substrate, a liquid crystal panel connected to a connection terminal portion formed at an end of the flexible substrate, and a light source mounting portion on a light source mounting surface of the flexible substrate. A light source and a backlight unit that is disposed on the back side of the liquid crystal panel and houses the light source, wherein the flexible substrate is interposed between the connection terminal portion and the light source mounting portion. A first bent portion provided; and a second bent portion provided between the first bent portion and the light source mounting portion. In the first bent portion, the flexible substrate includes: The light source mounting surface of the flexible substrate is bent on the back side of the backlight unit, and the second bent In part, the light source mounting surface of the flexible substrate is bent on the backlight unit side, in which the light source is accommodated in the backlight unit. Thereby, the position shift of a light source can be prevented.

  The liquid crystal module according to a second aspect of the present invention is the above liquid crystal module, wherein the flexible substrate is between an end of the flexible substrate where the connection terminal portion is formed and an end opposite to the end. It is formed so as to protrude from the side, and has an extended bonding portion that bonds the flexible substrate and the backlight unit. Thereby, a backlight unit and a flexible substrate can be adhere | attached firmly and the position shift of a light source can be prevented effectively.

  The liquid crystal module according to a third aspect of the present invention is the above-described liquid crystal module, wherein the extended adhesive portion is extended along the side. Thereby, a backlight unit and a flexible substrate can be adhere | attached still more firmly and the position shift of a light source can be prevented more effectively.

  The liquid crystal module according to a fourth aspect of the present invention is the above liquid crystal module, wherein the extended adhesive portion is longer than a distance from the opposite end to the second bent portion. The distance between the other end of the flexible substrate and the second bent portion is longer. Thereby, a backlight unit and a flexible substrate can be adhere | attached still more firmly and the position shift of a light source can be prevented more effectively.

  A liquid crystal module according to a fifth aspect of the present invention is the above liquid crystal module, comprising: an adhesive portion provided between the opposite end and the light source mounting portion; and the extended adhesive portion and the adhesive The part is formed so as to surround the light source mounting part in a U-shape. Thereby, a backlight unit and a flexible substrate can be adhere | attached still more firmly and the position shift of a light source can be prevented more effectively.

  A liquid crystal module according to a sixth aspect of the present invention is the above liquid crystal module, comprising: an adhesive portion provided between the opposite end and the light source mounting portion; and the extending adhesive portion and the adhesive portion The part is formed so as to surround the light source mounting part in a square shape. Thereby, a backlight unit and a flexible substrate can be adhere | attached still more firmly and the position shift of a light source can be prevented more effectively.

  In the display module according to a seventh aspect of the present invention, in the above display module, the backlight unit has a frame formed in a frame shape, and the extended bonding portion and the bonding portion are formed on the frame. It is provided correspondingly. The present invention is particularly effective in such a case.

  The display module according to an eighth aspect of the present invention is the display module described above, wherein the connection terminal portion and the portion up to the second bent portion are not bonded to the backlight unit. Thereby, position shift to a light source can be prevented more effectively.

  According to the present invention, it is possible to provide a high-quality liquid crystal module in which the positional deviation of the light source is prevented.

  A liquid crystal display module 100 according to an embodiment of the present invention will be described with reference to FIGS. FIG. 1 is a plan view of the liquid crystal display module 100 according to the present embodiment as viewed from the back. FIG. 2 is a plan view showing a configuration of a flexible printed circuit (FPC) 103 used in the liquid crystal display module 100 according to the present embodiment. 3 is a cross-sectional view taken along the line AA in FIG. 1, and FIG. 4 is a cross-sectional view taken along the line BB in FIG.

  As shown in FIGS. 1 to 4, the liquid crystal display module 100 according to the present embodiment includes a liquid crystal display panel 101, a backlight unit 102, an FPC 103, a light source 106, a double-sided tape 107, and the like. The backlight unit 102 includes a light guide plate 112, a frame 113, and the like. In the liquid crystal display module 100 according to the present invention, the FPC 103 bent to the non-viewing side (back side) of the liquid crystal display panel 101 is peeled off from the frame 113 and the light source 106 is prevented from shifting from the light incident end face of the light guide plate 112. It is.

  The liquid crystal display panel 101 displays an image. As shown in FIGS. 3 and 4, the liquid crystal display panel 101 includes an element substrate 108 and a counter substrate 109 disposed to face the element substrate 108. Transparent electrodes for forming display pixels made of, for example, ITO are formed on surfaces of the element substrate 108 and the counter substrate 109 facing each other. The element substrate 108 and the counter substrate 109 are fixed by a sealing material (not shown) formed in a frame shape. In addition, liquid crystal (not shown) is sealed in a space surrounded by the element substrate 108, the counter substrate 109, and the sealing material. Further, a viewing side polarizing plate 110 is attached to the viewing side of the element substrate 108, and an anti-viewing side polarizing plate 111 is attached to the counter-viewing side of the counter substrate 109.

  In such a liquid crystal display panel 101, one of the element substrate 108 and the counter substrate 109 is formed larger than the other counter substrate 109 in the present embodiment. A lead wire (not shown) formed by extending from the transparent electrode is formed on the projecting portion of the large element substrate 108, and a terminal portion (not shown) is formed at the end of the lead wire. . In the present embodiment, the terminal portion is provided on the non-viewing side (back side) of the element substrate 108 shown in FIG.

  Various types of liquid crystal display panel 101 can be used. For example, an active type liquid crystal display panel having a switch element in each pixel, a passive type liquid crystal display panel having no switch element, or a liquid crystal display panel such as a transmissive type or a transflective type is used. You can also. It is also possible to use a liquid crystal display panel in any mode such as a TN (Twisted Nematic) mode, an STN (Super Twisted Nematic) mode, or an IPS (In Plane Switching) mode.

  The backlight unit 102 constitutes a planar light source device that irradiates the liquid crystal display panel 101 with planar light. By storing a light source 106 to be described later in the backlight unit 102, a planar light source device that irradiates the liquid crystal display panel 101 with planar light is completed. The backlight unit 102 is provided on the non-viewing side of the liquid crystal display panel 101, that is, the back side. Therefore, the backlight unit 102 becomes a back member disposed on the back side of the liquid crystal display panel 101. As shown in FIG. 1, the backlight unit 102 includes a light guide plate 112, an optical member such as a reflection sheet and a prism sheet (not shown), a frame 113 that houses the optical member, and the like.

  As shown in FIG. 1, the frame 113 is formed in a frame shape from a resin material such as polycarbonate resin. The length of the light guide plate 112 in the longitudinal direction is shorter than the length of the frame 113 in the longitudinal direction. The light guide plate 112 is housed in the frame 113 so that a constant interval is formed between the frame 113 and the light incident end face of the light guide plate 112. Thereby, the light source storage part 114 which stores the light source 106 is formed. That is, the space between the inner surface of the frame-shaped frame 113 and the light incident end surface of the light guide plate 112 is the light source storage portion 114. Therefore, the light source storage part 114 is located in the vicinity of the light incident end face of the light guide plate 112.

  The FPC 103 is electrically and physically connected to a terminal portion provided on one side of the element substrate 108 constituting the liquid crystal display panel 101 by an ACF (Anisotropic Conductive Film) (not shown). The FPC 103 has a configuration in which a plurality of wiring patterns (not shown) made of a metal material such as Cu are formed on a flexible insulating substrate made of polyimide resin or the like. Although not shown here, the FPC 103 is mounted with chip components such as a driving IC chip and a capacitor. Further, a light source 106 such as an LED is mounted on the FPC 103. Various control signals are supplied to the transparent electrode of the liquid crystal display panel 101, the light source 106, and the like through a wiring pattern formed on the FPC 103.

  Here, the FPC 103 will be described in detail with reference to FIG. FIG. 2 is a plan view showing a configuration of the FPC 103 used in the liquid crystal display module 100 according to the present embodiment. As shown in FIG. 2, the FPC 103 according to the present embodiment includes a first bent portion 104, a second bent portion 105, a light source 106, a double-sided tape 107, an adhesive portion 115, an extended adhesive portion 116, and a connection terminal portion. 117 and a wiring pattern portion 118.

  The connection terminal portion 117 is formed at one end of the FPC 103 and is connected to a terminal portion provided on the element substrate 108 of the liquid crystal display panel 101. In FIG. 2, the connection terminal portion 117 is formed on the front side of the FPC 103. On the other hand, an adhesive portion 115 is provided at the end of the FPC 103 opposite to the end where the connection terminal portion 117 is formed. The bonding portion 115 is formed along the end side of the FPC 103. In addition, a double-sided tape 107 that bonds the FPC 103 and the frame 113 is disposed in the bonding portion 115.

  A light source 106 is mounted in the vicinity of the bonding portion 115. In the present embodiment, the three light sources 106 are arranged in a line along the bonding portion 115. Here, a surface on which the light source 106 of the FPC 103 is mounted is referred to as a light source mounting surface P, and a region where the light source 106 is mounted is referred to as a light source mounting portion Q. In FIG. 2, the light source mounting surface P is a surface on the front side of the FPC 103. That is, the adhesive portion 115 is provided between the light source mounting portion Q and the end opposite to the end where the connection terminal portion 117 of the FPC 103 is formed. Further, the connection terminal portion 117 described above is provided on the light source mounting surface P.

  Further, the wiring pattern described above is formed between the light source 106 and the connection terminal portion 117. Therefore, a region between the light source 106 and the connection terminal portion 117 becomes the wiring pattern portion 118. In the wiring pattern portion 118, the first bent portion 104 is provided between the connection terminal portion 117 of the FPC 103 and the light source mounting portion Q. Further, a second bent portion 105 is provided between the first bent portion 104 and the light source mounting portion Q. That is, between the connection terminal portion 117 and the light source mounting portion Q, the first bent portion 104 and the second bent portion 105 are formed in this order.

  As shown in FIG. 3, the connection terminal portion 117 of the FPC 103 and the terminal portion formed on the non-viewing side of the element substrate 108 are connected. The FPC 103 is bent at the first bent portion 104 to the opposite viewing side of the liquid crystal display panel 101, that is, the back side. That is, the FPC 103 is bent to the side where the backlight unit 102 is disposed on the liquid crystal display panel 101. Therefore, when the FPC 103 is bent in the first bent portion 104, the light source mounting surface P of the FPC 103 is disposed on the side opposite to the backlight unit of the FPC 103.

  Further, in the FPC 103, the light source mounting surface P of the FPC 103 is bent toward the backlight unit 102 side of the FPC 103 at the second bent portion 105. That is, the FPC 103 is bent twice at the first bent portion 104 and the second bent portion 105 so as to be wound into a flat shape.

  The light source 106 mounted on the FPC 103 is stored in a light source storage unit 114 provided on the frame 113 of the backlight unit 102 by bending the FPC 103. The light irradiation unit of the light source 106 is disposed along the light incident end surface of the light guide plate 112. Thus, by storing the light source 106 in the light source storage unit 114, a planar light source device that irradiates the liquid crystal display panel 101 with planar light is obtained.

  Further, one end of the FCP 103 connected to the liquid crystal display panel 101 and the portion up to the second bent portion 105 are not fixed to the frame 113 of the backlight unit 102. That is, the FPC 103 is bonded by the double-sided tape 107 on the light source mounting portion Q side with respect to the second bent portion 105.

  Conventionally, the FPC bent to the back side of the liquid crystal display panel has been fixed with a double-sided tape or the like. However, in a high temperature and high humidity environment, there is a problem that the adhesive ability of the double-sided tape is lowered, and the FPC peels off due to the elastic restoring force of the conductor thin film and the insulating thin film constituting the FPC. In addition, when a light source is conventionally mounted on the FPC side, there is a problem that the luminance is lowered due to the light source being displaced from the light incident end face of the light guide plate due to peeling of the FPC. Further, if the optical axis of the light source is deviated, there is a possibility that uneven light emission may occur.

  However, according to the present invention, the FPC 103 is bent twice in a U-shape, and one end of the FPC 103 connected to the liquid crystal display panel 101 and the portion up to the second bent portion 105 are formed in the backlight unit 102. It is not fixed. For this reason, the elastic restoring force of the FPC 103 works to press the backlight unit 102. Due to the elastic restoring force of the FPC 103, the light source 106 is pressed against the light incident end face of the light guide plate 112 constituting the backlight unit 102. Therefore, even if the FPC 103 is detached from the frame 113, the light source 106 is not displaced from the light incident end face of the light guide plate 112, and the problem that the luminance is reduced can be solved. Furthermore, the occurrence of uneven light emission due to the deviation of the optical axis of the light source can also be suppressed.

  In addition, an extended bonding portion 116 is provided so as to extend from both ends of the bonding portion 115 formed along the end side of the FPC 103. That is, the extended bonding portion 116 is formed on the side of the light source mounting portion Q. That is, the extended bonding portion 116 is formed so as to protrude from the side between the end where the connection terminal portion 117 of the FPC 103 is formed and the end where the opposite bonding portion 115 is formed.

  Further, the two extended bonding portions 116 provided at both ends of the bonding portion 115 are formed in a direction perpendicular to the bonding portion 115 and are formed in the same direction. In other words, the extended bonding portion 116 extends along the side between the end where the connection terminal portion 117 of the FPC 103 is formed and the end where the opposite bonding portion 115 is formed. Here, the two extended bonding portions 116 are formed in a direction from the end where the bonding portion 115 of the FPC 103 is provided toward the connection terminal portion 117. Therefore, the bonding portion 115 and the extended bonding portion 116 are formed so as to surround the light source mounting portion Q in a U shape. That is, the bonding portion 115 and the extended bonding portion 116 are formed so as to surround three sides of the light source mounting portion Q. A cut is formed between the extended bonding portion 116 and the wiring pattern forming portion 118 of the FPC 103. Therefore, even when the FPC 103 is bent by the second bent portion 105, the extended bonding portion 116 cannot be bent.

  In addition, the extended bonding portion 116 is provided with a double-sided tape 107 that bonds the FPC 103 and the frame 113. The double-sided tape 107 is continuously formed across the adhesive portion 115 and the extended adhesive portion 116. Therefore, the double-sided tape 107 is formed in a U-shape so as to surround the light source mounting portion Q, as indicated by a dashed line in FIG. That is, the double-sided tape 107 is formed so as to surround three sides of the light source mounting portion Q. Thereby, the FPC 103 and the frame 113 can be more firmly fixed, and the FPC 103 can be prevented from being detached from the frame 113. Therefore, the positional deviation of the light source 106 can be prevented, and the high-quality liquid crystal display module 100 can be provided.

  Moreover, it is preferable that the extended bonding part 116 is longer than the distance between the end of the FPC 103 where the bonding part 115 is formed and the second bent part 105. As a result, the FPC 103 and the frame 113 can be more firmly bonded, and the floating of the FPC 103 can be further suppressed.

  Further, as described above, the frame 113 of the backlight unit 102 has a frame shape, and the extended bonding portion 116 and the bonding portion 115 are provided corresponding to the shape of the frame 113. Is preferred. As a result, it is possible to prevent the double-sided tape 107 from coming into contact with the light guide plate 112 or the reflection sheet disposed on the back surface thereof, thereby causing defects such as uneven light emission.

  The shape of the frame 113 is not limited to a frame shape. For example, it may be formed so as to cover the back side of the light guide plate 112. FIG. 5 is a view of the configuration of the liquid crystal display module 100 in such a case as viewed from the back. As shown in FIG. 5, a light source storage portion 119 is formed on the frame 113. The light source 106 is stored in the light source storage unit 119 by bending the FPC 103 with the first bent unit 104 and the second bent unit 105.

  And the two extended adhesion parts 116 extended from the both ends of the adhesion part 115 are connected at the front ends. That is, the extended bonding portion 116 has a U shape. Accordingly, the extended bonding portion 116 and the bonding portion 115 are formed so as to surround the light source mounting portion Q in a square shape. That is, the extended bonding portion 116 and the bonding portion 115 are formed so as to surround the four sides of the light source mounting portion Q.

  In addition, the extended bonding portion 116 is provided with a double-sided tape 107 that bonds the FPC 103 and the frame 113. The double-sided tape 107 is continuously formed across the adhesive portion 115 and the extended adhesive portion 116. Therefore, the double-sided tape 107 is formed in a square shape so as to surround the light source mounting portion Q. That is, the double-sided tape 107 is formed so as to surround the light source mounting portion Q. Thereby, the FPC 103 and the frame 113 can be more firmly fixed, the peeling of the FPC 103 can be suppressed, and the positional deviation of the light source 106 can be prevented.

  In FIG. 1, the FPC 103 is connected to the non-viewing side of the element substrate 108, but the FPC 103 can be connected to the viewing side of the element substrate 108 or the counter substrate 109.

It is the top view which looked at the structure of the display module which concerns on this invention from the back. It is a top view which shows the structure of the flexible substrate used for the display module which concerns on this invention. It is AA sectional drawing of FIG. It is BB sectional drawing of FIG. It is the top view which looked at the other structure of the display module which concerns on this invention from the back surface. It is sectional drawing of the conventional display module.

Explanation of symbols

DESCRIPTION OF SYMBOLS 100 Liquid crystal display module 101 Liquid crystal display panel 102 Backlight unit 103 Flexible board 104 1st bending part 105 2nd bending part 106 Light source 107 Double-sided tape 108 Element board | substrate 109 Opposite substrate 110 Non-viewing side polarizing plate 111 Viewing side polarizing plate 112 Light guide plate 113 Frame 114 Light source storage portion 115 Adhesion portion 116 Extension bonding portion 117 Connection terminal portion 118 Wiring pattern portion 119 Light source storage portion P Light source mounting surface Q Light source mounting portion

Claims (8)

A flexible substrate;
A liquid crystal panel connected to a connection terminal portion formed at an end of the flexible substrate;
A light source mounted on a light source mounting portion of a light source mounting surface of the flexible substrate;
A backlight unit disposed on the back side of the liquid crystal panel and storing the light source;
A liquid crystal module comprising:
The flexible substrate is
A first bent portion provided between the connection terminal portion and the light source mounting portion;
A second bent portion provided between the first bent portion and the light source mounting portion;
In the first bent portion, the flexible substrate is bent toward the back side of the backlight unit, and the light source mounting surface of the flexible substrate is disposed on the anti-backlight unit side,
The liquid crystal module in which the light source mounting surface of the flexible substrate is bent toward the backlight unit in the second bent portion, and the light source is housed in the backlight unit.   The flexible substrate is formed so as to protrude from a side between the end where the connection terminal portion of the flexible substrate is formed and an end opposite to the end, and the flexible substrate and the backlight unit are connected to each other. The liquid crystal module according to claim 1, further comprising an extended adhesion portion to be adhered.   The liquid crystal module according to claim 2, wherein the extended adhesive portion extends along the side.   The liquid crystal module according to claim 3, wherein the extended adhesive portion is longer than a distance from the opposite end to the second bent portion. Having an adhesive portion provided between the opposite end and the light source mounting portion;
5. The liquid crystal module according to claim 2, 3, or 4, wherein the extended bonding portion and the bonding portion are formed so as to surround the light source mounting portion in a U shape. Having an adhesive portion provided between the opposite end and the light source mounting portion;
5. The liquid crystal module according to claim 2, 3, or 4, wherein the extended bonding portion and the bonding portion are formed so as to surround the light source mounting portion in a square shape. The backlight unit has a frame formed in a frame shape,
The liquid crystal module according to claim 5, wherein the extended bonding portion and the bonding portion are provided corresponding to the frame.   The liquid crystal module according to any one of claims 1 to 7, wherein a portion from the connection terminal portion to the second bent portion is not bonded to the backlight unit.

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