JP2012154970A - Liquid crystal module - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a liquid crystal module in which the reduction of costs is attained by excluding a conventional LED drive circuit or LED mounted substrate and a heat radiation property of LED is also improved.SOLUTION: A liquid crystal panel 1 is disposed on a front side of a light guide plate 2, an X-wiring board 3 composed of a metal core substrate is disposed on the same plane as the liquid crystal panel 1 along with one side of the liquid crystal panel 1, and the liquid crystal panel 1 and the X-wiring board 3 are connected by a COF 5. A liquid crystal panel drive circuit unit 3a is mounted on a front face of the X-wiring board 3, LEDs 4 are mounted on a rear face of the X-wiring board 3 while forming one line along with an end face of the light guide plate 2, and an LED drive circuit unit 3b is mounted on the rear face of the X-wiring board 3. Therefore, a liquid crystal module is configured by bringing the X-wiring board 3 into contact with a metallic bezel 7. The X-wiring board 3 is shared as a substrate to mount an LED drive circuit or LEDs, so that the reduction of costs can be attained by excluding such a substrate, and a heat radiation property is improved by bringing the X-wiring board 3 composed of the metal core substrate into contact with the bezel 7.

Description

  The present invention relates to an edge light type liquid crystal module using LEDs (light emitting diodes). More specifically, the present invention aims to reduce the cost by omitting the LED driving circuit and the substrate on which the LEDs are mounted, and to improve the heat dissipation of the LEDs. The present invention relates to a liquid crystal module.

  An edge-light type liquid crystal module incorporated in a thin-screen large-screen liquid crystal television is a liquid crystal module in which a liquid crystal panel and an X-wiring board are connected by a COF (chip on film), and the COF is bent at a substantially right angle. It is installed on the side of the rear frame. Then, the LED driving circuit and the substrate on which the LED is mounted are arranged along the end face of the light guide plate on the back side of the liquid crystal panel, and the light incident on the light guide plate from the LED is irradiated from the surface of the light guide plate to the liquid crystal panel. .

  On the other hand, in the field of small display devices incorporated in mobile phones and the like, a flexible substrate is not bent and is electrically connected to the liquid crystal driving IC at the first connection portion, and a light source is mounted at the second connection portion. In addition, a display device (Patent Document 1) designed to be smaller and thinner, and an external input substrate mounted with LEDs and a flexible substrate separated from each other are electrically and mechanically connected to the display side of the liquid crystal cell, 2. Description of the Related Art A flat display device (Patent Document 2) in which an output side of a wiring of an external input substrate and an input side of a flexible substrate wiring to an LED are connected by a wiring portion formed in a liquid crystal cell is known.

JP 2006-133448 A JP 2009-128594 A

However, since the conventional edge light type liquid crystal module is provided with an LED driving circuit and a substrate on which the LED is mounted in addition to the X-wiring substrate, the cost of the substrate and the FFC (flexible flat) for connecting each substrate to the main substrate are provided. There was a problem that the cost of the cable) increased.
In addition, since the X-wiring board is attached to the side surface of the rear frame of the liquid crystal module by bending the COF, it is necessary to use a COF having a large length, and there is a problem that the cost of the COF increases. .
Furthermore, the LED is a light source that generates a large amount of heat and easily deteriorates. However, the conventional liquid crystal module has insufficient measures for heat dissipation of the LED. There was also a problem.

  These problems cannot be solved by using the technology of the small display device disclosed in Patent Documents 1 and 2.

  The present invention has been made under the above circumstances, and the problem to be solved is that the X-wiring board is shared as the LED driving circuit and the board for mounting the LED, and the conventional LED driving circuit and the LED are mounted. An object of the present invention is to provide a liquid crystal module that is improved so as to reduce the cost by omitting the substrate, to reduce the cost by eliminating the need to bend the COF, and to improve the heat dissipation of the LED.

  In order to solve the above problems, a liquid crystal module according to the present invention includes a liquid crystal panel disposed on the surface side of a light guide plate, an X-wiring board disposed on the same plane as the liquid crystal panel along one side of the liquid crystal panel, The panel and the X-wiring board are connected by COF, the liquid crystal panel drive circuit unit is mounted on the surface of the X-wiring board, the LEDs are arranged in a line along the end face of the light guide plate, and are mounted on the back surface of the X-wiring board. The drive circuit unit is mounted on the back surface of the X-wiring board.

In the liquid crystal module of the present invention, the X-wiring substrate is preferably a metal core substrate.
And it is preferable to make the surface except the liquid crystal panel drive circuit part of this X-wiring board contact with a metal bezel.
Furthermore, it is also preferable that the surface of the X-wiring substrate excluding the liquid crystal panel drive circuit portion and the COF are brought into contact with a metal bezel.

Like the liquid crystal module of the present invention, the X-wiring board is shared, the liquid crystal panel driving circuit unit is mounted on the surface of the X-wiring board, and the LEDs are arranged in a line along the end face of the light guide plate. Mounting on the back side and mounting the LED drive circuit part on the back side of the X-wiring board eliminates the conventional LED drive circuit and the board on which the LED is mounted, so the cost of the board and the connection between each board and the main board Cost savings can be achieved with significant savings in FFC costs.
Further, as in the liquid crystal module of the present invention, when the X-wiring board is arranged on the same plane as the liquid crystal panel along one side of the liquid crystal panel and the liquid crystal panel and the X-wiring board are connected by COF, the COF needs to be bent. Since the X-wiring board and the liquid crystal panel can be connected using a COF having a much smaller length than the conventional COF, the cost of the COF can be saved and the cost can be reduced.

In the liquid crystal module of the present invention, if the X-wiring board is a metal core board, this board serves as a heat sink for the LED, and heat generated in the LED is quickly conducted to the metal core board to improve heat dissipation. It is possible to prevent a decrease in luminance due to thermal degradation of the.
And when the surface excluding the liquid crystal panel drive circuit part of the X-wiring board made of this metal core board is in contact with a metal bezel, the heat conducted from the LED to the X-wiring board is further conducted to the bezel. Since heat is radiated from the surface of the bezel, heat dissipation can be further enhanced.
In addition to the heat generated from the LED, the heat generated from the COF is obtained when the surface of the X-wiring board made of the metal core substrate excluding the liquid crystal panel drive circuit unit and the COF are in contact with the metal bezel. Since heat is also radiated from the surface of the bezel, the heat radiation effect can be further enhanced.

It is a front view of the liquid crystal module concerning one embodiment of the present invention. It is an AA line expanded sectional view of FIG. It is a front view of the liquid crystal module in which a bezel and a rear frame are omitted. It is a rear view of the same liquid crystal module which omitted a bezel and a rear frame.

  Hereinafter, embodiments of a liquid crystal module according to the present invention will be described in detail with reference to the drawings.

  The liquid crystal module of the present embodiment is an edge-light type liquid crystal module incorporated in a thin-screen large-screen liquid crystal television or the like, and includes a liquid crystal panel 1, a light guide plate 2, an X-wiring board 3, an LED (light emitting diode) 4, and a COF. (Chip on film) 5, a rear frame 6, a bezel 7, and the like.

  That is, as shown in FIG. 2, a light guide plate 2 made of synthetic resin having excellent translucency is accommodated inside a shallow box-shaped rear frame 6 made of sheet metal, with its end portions supported by spacers 8. Has been. The light guide plate 2 emits the light of the LED 4 incident from the end face thereof from the front surface of the light guide plate and emits light, thereby irradiating the liquid crystal panel 1 from the back surface to display a bright display. A white reflective coating film is formed on the back surface of the light guide plate 2 in order to totally reflect light to be emitted from the back surface of the light guide plate and use it without waste. Therefore, in the liquid crystal module of this embodiment, a light reflection sheet is not provided between the light guide plate 2 and the rear frame 6, but when the light guide plate 2 having no reflective coating film formed on the back surface is used, A light reflecting sheet is provided between 2 and the rear frame 6.

  A liquid crystal panel 1 is arranged on the surface side of the light guide plate 2 as shown in FIG. 2, and as shown in FIGS. 2 and 3, along the one side (upper side) of the liquid crystal panel 1, X− The wiring board 3 is arranged on the same plane as the liquid crystal panel 1. The X-wiring board 3 and the liquid crystal panel 1 are electrically and mechanically connected by a plurality of COFs 5. Since the X-wiring substrate 3 is arranged on the same plane as the liquid crystal panel 1 along the upper side of the liquid crystal panel 1 as described above, a COF 5 having a shorter length than the conventional COF is used. The X-wiring board 3 and the liquid crystal panel 1 are connected in a flat state without being bent as in the conventional COF. Note that a gap is formed between the X-wiring substrate 3 and the liquid crystal panel 1 to accommodate the IC chip of the COF 5.

  The X-wiring board 3 of the present embodiment is a metal core board made of aluminum or the like, and as shown in FIGS. 2 and 3, the surface of the edge of the X-wiring board 3 opposite to the liquid crystal panel 1 side. A liquid crystal panel drive circuit unit 3a is mounted on the surface of the X-wiring board 3 excluding the liquid crystal panel drive circuit unit 3a, in other words, between the liquid crystal panel drive circuit unit 3a and the thermocompression bonding portion of the COF 5 The substrate surface in between is a metal exposed surface from which the metal is exposed. Further, on the back surface of the edge portion of the X-wiring substrate 3 on the liquid crystal panel 1 side, as shown in FIGS. 2 and 4, a large number of LEDs 4 are arranged along the end surface of the light guide plate 2 with a certain mutual interval. In addition, an LED drive circuit unit 3b for driving the LED 4 is mounted on the back surface of the edge of the X-wiring board 3 opposite to the liquid crystal panel 1 side. . That is, the X-wiring board 3 is shared as a conventional LED driving circuit or a board on which the LED is mounted. The power supply of the liquid crystal panel drive circuit unit 3a and the power supply of the LED drive circuit unit 3b are shared.

  As shown in FIGS. 1 and 2, the four peripheral edges of the liquid crystal panel 1 are surrounded by a sheet metal bezel 7, and the X-wiring board 3 is also covered with the bezel 7. As shown in FIG. 2, the metal exposed surface of the surface of the X-wiring substrate 3 is in contact with the bezel 7, and the bezel 7 is further in contact with the COF 5.

Although not shown, a Y-wiring board is electrically and mechanically connected to the left or right side of the liquid crystal panel 1 via a COF. The Y-wiring board is connected to the rear frame 6. It is attached to either the left or right side plate. The X-wiring board 3 and the Y-wiring board are connected to a main board (not shown) attached to the rear surface of the rear frame 6 by FFC.
Further, an optical sheet such as a light diffusing sheet is provided between the light guide plate 2 and the liquid crystal panel 1 as necessary for the purpose of suppressing variation in luminance.

  Since the liquid crystal module configured as described above shares the X-wiring board 3 as an LED driving circuit or a board on which an LED is mounted, it is possible to omit a conventional LED driving circuit or a board on which an LED is mounted. Since the cost of the board and the cost of the FFC for connecting each board to the main board can be greatly saved, cost reduction can be achieved.

  Further, the X-wiring board 3 is arranged on the same plane as the liquid crystal panel 1 along the upper side of the liquid crystal panel 1, and the liquid crystal panel 1 and the X-wiring board 3 are connected using a COF 5 having a short length. Therefore, the number of COFs 5 to be taken from one COF material sheet is increased, and the material cost of the COF 5 can be saved by that amount, thereby achieving cost reduction.

Furthermore, since the liquid crystal module of this embodiment uses a metal core substrate as the X-wiring substrate 3, the X-wiring substrate 3 serves as a heat sink for the LED 4, and the metal exposed surface of the X-wiring substrate 3 Since it is in contact with the metal bezel 7, the heat generated from the LED 4 is quickly conducted to the X-wiring board 3 to be temporarily stored, and is quickly conducted to the bezel 7 to be efficiently transmitted from the surface of the bezel 7. It will be well radiated. Therefore, the heat dissipation is greatly improved, and the deterioration of the LED 4 due to heat can be suppressed, so that a reduction in luminance can be sufficiently prevented.
And in the liquid crystal module of this embodiment, since the COF 5 is also brought into contact with the bezel 7 to improve heat dissipation, the life of the IC chip of the COF 5 is increased, and the lifetime of the LED 4 is increased. The durability of the liquid crystal module can be further enhanced.

  In the liquid crystal module of the above embodiment, the X-wiring board 3 is shared as an LED driving circuit or a board for mounting the LED. However, when the LED 4 is arranged along either the left or right end face of the light guide plate 2. The Y-wiring board is shared as an LED driving circuit and a board for mounting the LED, the liquid crystal panel driving circuit unit 3a is mounted on the surface of the Y-wiring board, and the LED driving circuit unit 3b is mounted on the back surface of the Y-wiring board. What is necessary is just to mount LED4.

DESCRIPTION OF SYMBOLS 1 Liquid crystal panel 2 Light guide plate 3 X-wiring board 3a Liquid crystal panel drive circuit part 3b LED drive circuit part 4 LED
5 COF
6 Rear frame 7 Bezel

Claims (4)

  A liquid crystal panel is arranged on the surface side of the light guide plate, an X-wiring board is arranged on the same plane as the liquid crystal panel along one side of the liquid crystal panel, the liquid crystal panel and the X-wiring board are connected by COF, and X-wiring The liquid crystal panel drive circuit unit is mounted on the surface of the substrate, the LEDs are arranged in a line along the end face of the light guide plate and mounted on the back surface of the X-wiring board, and the LED drive circuit portion is mounted on the back surface of the X-wiring board. A featured liquid crystal module.   The liquid crystal module according to claim 1, wherein the X-wiring substrate is a metal core substrate.   3. The liquid crystal module according to claim 1, wherein a surface of the X-wiring board excluding a liquid crystal panel driving circuit portion is brought into contact with a metal bezel.   3. The liquid crystal module according to claim 1, wherein the surface of the X-wiring board excluding the liquid crystal panel drive circuit section and the COF are brought into contact with a metal bezel.

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