JPH11305227A - Liquid crystal display - Google Patents

Abstract

(57) [Problem] To reduce the thickness of a connection portion between a drain-side flexible substrate and an interface substrate to further promote a thinner module. SOLUTION: A flexible substrate FPC2 on the drain side is provided.
Protruding portion JT2 which is formed on a side edge adjacent to the interface substrate of the above in a substantially perpendicular direction and has a connection terminal CT4 on the surface.
The connection terminal CT4 of the projection JT2 is connected to the connector of the interface substrate in a state where the flexible substrate FPC2 is bent to the back of the liquid crystal display element, and the portion of the projection JT2 on which the connection terminal CT4 is mounted is the flexible substrate. It was configured to be folded upside down without overlapping with FPC2.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid crystal display device, and more particularly to a liquid crystal display device in which a liquid crystal display device having a driving IC mounted on an edge of a substrate and a backlight source are superposed.

[0002]

2. Description of the Related Art A liquid crystal display device has been widely used as a display device capable of high-definition and color display for a notebook computer or a display monitor.

[0003] The liquid crystal display device includes a simple matrix type using a liquid crystal panel in which a liquid crystal layer is sandwiched between a pair of substrates on which parallel electrodes formed so as to cross each other are formed on each inner surface;
2. Description of the Related Art An active matrix type liquid crystal display device using a liquid crystal display element (hereinafter, also referred to as a liquid crystal panel) having a switching element for selecting a pixel in one of a pair of substrates is known.

An active matrix type liquid crystal display device is
As represented by a twisted nematic (TN) system, a so-called vertical electric field type liquid crystal display device using a liquid crystal panel in which an electrode group for pixel selection is formed on each of a pair of upper and lower substrates (an upper substrate and a lower substrate) ( A so-called in-plane switching type liquid crystal display device (generally referred to as a TN type active matrix type liquid crystal display device) and a liquid crystal panel using a liquid crystal panel in which an electrode group for pixel selection is formed on only one of a pair of upper and lower substrates. IPS mode liquid crystal display device).

In the liquid crystal panel constituting the former TN mode active matrix type liquid crystal display device, the liquid crystal is twisted by 90 ° in a pair (two) of substrates, and is absorbed on the outer surfaces of the upper and lower substrates of the liquid crystal panel. Two polarizing plates are laminated with the axial direction arranged in crossed Nicols and the absorption axis on the incident side made parallel or perpendicular to the rubbing direction.

In such a TN type active matrix type liquid crystal display device, when no voltage is applied, the incident light becomes linearly polarized light on the incident side polarizing plate, and this linearly polarized light propagates along the twist of the liquid crystal layer, and the outgoing side polarized light. When the transmission axis of the plate coincides with the azimuthal angle of the linearly polarized light, all the linearly polarized light is emitted and white display is performed (a so-called normally open mode).

When a voltage is applied, the direction (director) of a unit vector indicating the average alignment direction of the liquid crystal molecular axes constituting the liquid crystal layer is oriented in a direction perpendicular to the substrate surface, and the azimuth of the incident side linearly polarized light. Since the angle does not change, it coincides with the absorption axis of the exit-side polarizing plate, so that black display is performed. (See "Basics and Applications of Liquid Crystals" published by the Industrial Research Council in 1991).

On the other hand, an electrode group for pixel selection and an electrode wiring group are formed only on one of a pair of substrates, and a voltage is applied between adjacent electrodes (between a pixel electrode and a counter electrode) on the substrate by applying a voltage. In an IPS type liquid crystal display device in which layers are switched in a direction parallel to the substrate surface, a polarizing plate is arranged so as to display black when no voltage is applied (a so-called normally closed mode).

The liquid crystal layer of this IPS mode liquid crystal display device is
In the initial state, the director of the liquid crystal layer is in a homogeneous orientation parallel to the substrate surface, and in a plane parallel to the substrate, the director of the liquid crystal layer is parallel or somewhat angled with the electrode wiring direction when no voltage is applied, and the liquid crystal layer is oriented when the voltage is applied. The direction of the director shifts in a direction perpendicular to the electrode wiring direction with the application of the voltage, and the director direction of the liquid crystal layer is 45 times smaller than the director direction when no voltage is applied.
° When tilted in the electrode wiring direction, the liquid crystal layer at the time of applying the voltage has an azimuth of 90 degrees of polarization as if it were a half-wave plate.
And the azimuth of the polarized light coincides with the transmission axis of the exit-side polarizing plate, and a white display is obtained.

This IPS mode liquid crystal display device has a feature that a change in hue and contrast is small even at a viewing angle and a wide viewing angle is achieved (Japanese Patent Laid-Open No. 5-505).
247).

In the above-mentioned full-color liquid crystal display devices, a color filter system is mainly used. In this method, a pixel corresponding to one dot of color display is divided into three, and a color filter corresponding to each of three primary colors, for example, red (R), green (G), and blue (B) is arranged in each unit pixel. This is achieved by doing so.

The present invention can be applied to the above-mentioned various liquid crystal display devices. The outline of the present invention will be described below by taking a TN type active matrix type liquid crystal display device as an example.

As described above, in a liquid crystal display element (also referred to as a liquid crystal panel) constituting a TN type active matrix type liquid crystal display device (for simplicity, hereinafter simply referred to as an active matrix type liquid crystal display device), a liquid crystal layer is formed. A gate line group extending in the x direction and juxtaposed in the y direction on one of two substrates (transparent insulating substrates) made of glass or the like (transparent insulating substrate) made of glass or the like which face each other , A drain line group extending in the y direction while being insulated from the gate line group and juxtaposed in the x direction is formed.

Each region surrounded by the group of gate lines and the group of drain lines becomes a pixel region, and a switching element such as a thin film transistor (T
FT) and a transparent pixel electrode.

When the scanning signal is supplied to the gate line, the thin film transistor is turned on, and a video signal from the drain line is supplied to the pixel electrode via the turned on thin film transistor.

In addition to the drain lines of the drain line group, the gate lines of the gate line group extend to the periphery of the substrate to form external terminals, and are connected to the external terminals. Video driving circuit, gate scanning driving circuit, that is, a plurality of driving ICs constituting them
(Semiconductor integrated circuit) is externally mounted around the substrate. In other words, a plurality of tape carrier packages (TCP) on which these drive ICs are mounted are externally provided around the substrate.

However, since such a substrate has a structure in which a TCP on which a driving IC is mounted is externally mounted, an intersecting region of a gate line group and a drain line group of the substrate is formed. The area occupied by the area between the outline of the display area and the outer frame of the substrate (usually called a frame) becomes large, and the liquid crystal display element is integrated with the illumination light source (backlight) and other optical elements. This is contrary to the desire to reduce the external dimensions of the liquid crystal display module.

Therefore, in order to solve such a problem as much as possible, that is, due to demands for high-density mounting of the liquid crystal display element and miniaturization of the outer shape of the liquid crystal display module, the video drive is performed without using TCP parts. The so-called flip-chip method or chip-on-glass (COG) method in which a scanning IC and a scanning drive IC are directly mounted on a substrate has been proposed.

The flip-chip type liquid crystal display device is disclosed in Japanese Patent Application No. 6-256426 filed by the same applicant.
There is a number.

[0020]

A liquid crystal display device of this type is, for example, a substrate made of two sheets of glass or the like at a predetermined gap so that the surfaces on which a transparent electrode for display and an alignment film are laminated face each other. Are superimposed, and the two substrates are bonded together with a sealing material provided in a frame shape (a square shape) in the vicinity of the peripheral portion between the two substrates, and the liquid crystal sealing opening, which is a cutout portion provided in a part of the sealing material. A liquid crystal display element having liquid crystal injected and sealed inside a sealing material between the two substrates, and a polarizing plate provided outside the two substrates, and the liquid crystal display element disposed on the back of the liquid crystal display element A liquid crystal driving circuit board disposed outside the outer periphery of the liquid crystal display element, a lower case which is a molded product for housing and holding the backlight, and housing the above members. Metal seal with display window Frame is composed of (upper case, also referred to as upper frame) and the like.

The backlight is, for example, a synthetic resin plate such as a transparent acrylic plate for guiding light emitted from a light source to a direction away from the light source and uniformly irradiating the entire surface of the liquid crystal display element with light. A linear light source (a fluorescent tube such as a cold cathode fluorescent lamp) arranged parallel to and along the end face near at least one end face (one side face) of the light guide body. A fluorescent tube is covered over substantially the entire length thereof, and a cross-sectional shape is substantially U-shaped, and a light source reflector whose inner surface is a reflection surface is disposed on a light guide, for example,
The upper surface is a prism surface formed by arranging a large number of triangular prisms in parallel, the lower surface is formed of a smooth surface, and the light of the backlight emitted over a wide angle range is aligned in a certain angle range, and the light guide is formed. A diffusion sheet for diffusing light from
It is composed of a prism sheet for improving the brightness of the backlight, a reflection sheet disposed below the light guide, and reflecting light from the light guide to the liquid crystal display element to the side.

The liquid crystal display element has a drive IC mounted on its long side and a short side adjacent to the long side, and has an interface circuit board (hereinafter simply referred to as an interface board) on the back of the short side. One side edge in the longitudinal direction is connected to the drive IC mounted on the side, the other side edge is bent to the back of the liquid crystal display element, and a connection terminal connected to the connector provided on the interface board from the lower surface of the interface board is provided. And a flexible circuit board (hereinafter, also simply referred to as a flexible board) for connecting various signals for display from the interface board to the drive IC.

An upper case in which an illumination light source is disposed on the lower surface of the liquid crystal display element and a window is formed in an effective display area of the liquid crystal display element, and a lower case in which a concave portion for holding the illumination light source is formed. To obtain a liquid crystal display device (liquid crystal display module).

FIG. 44 is a plan view schematically showing a main part of a flexible substrate on the drain side constituting a conventional liquid crystal display device. FIG. 45 is a plan view showing the connection of the flexible substrate on the drain side shown in FIG. It is principal part sectional drawing which illustrates typically the state which carried out. In each figure,
FPC2 is a flexible substrate on the drain side, FSL is a wiring portion to the drive IC, JT2 is a convex portion, CT4 is a connection terminal, CT2 is a connector, FPC1 is a flexible substrate on the gate side, SHD is an upper case (shield frame),
SUB1 is a lower substrate (TFT substrate) constituting a liquid crystal display element, SUB2 is an upper substrate (color filter substrate), P
OL1 and POL2 are polarizing plates, PCB is an interface board, and IC is a driving IC.

Drain side flexible substrate FPC2
The wiring portion FSL connected to the drain side driving IC mounted on the long side of the liquid crystal display element PNL and the connector CT2 mounted on the interface board PCB are described later.
And a convex part JT2 having a connection terminal CT4 connected to the second terminal. The protruding portion JT2 is formed in a direction substantially perpendicular to the end of the flexible board FPC2 on the interface board side, and a connection terminal CT4 is attached to the tip thereof. Note that CHD is a chip component (capacitor).

This flexible substrate FPC2 is similar to that shown in FIG.
Is folded at the edge of the lower substrate SUB1 indicated by the two-dot chain line on the back side of the liquid crystal display element. At this time, the connection terminal CT4
44 is folded back along a folding line BENTL indicated by a one-dot chain line in FIG. 44, and as shown in FIG. 45, the connector CT of the interface board PCB is formed.
2 is connected.

As described above, the conventional flexible substrate FP
Since the connection terminal CT4 of C2 and the connector CT2 of the interface board PCB are connected in a folded state in the vicinity of the connection terminal of the projection JT, the flexible board FPC2
Is doubled in this portion, the thickness of the entire liquid crystal display device (liquid crystal display module) in which the liquid crystal display element and the backlighting device are stacked and fixed by the upper case SHD and the lower case (not shown) is the flexible substrate It became thicker by one FPC2, which was one of the obstacles to thinning.

An object of the present invention is to provide a liquid crystal display device in which the thickness of the connecting portion between the above-mentioned flexible substrate and the interface substrate is reduced to further promote a thin module.

[0029]

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention provides a method for manufacturing a flexible board on the drain side, in which a folded portion of a projection having a connection terminal with an interface substrate is removed from a mounting portion of the connection terminal. This is performed at a remote position, and the convex portion does not overlap with the flexible substrate in a folded state. That is, the present invention is characterized by having the following configuration.

(1) A liquid crystal layer is sealed between two substrates,
A liquid crystal display element having a drive IC mounted on its long side and a short side adjacent to the long side; an interface board (PCB) disposed on the back side of the short side; Of the liquid crystal display element, and a connection terminal connected to a connector provided on the interface board from a lower surface of the interface board to display from the interface board. Board (FPC2) for connecting various signals for driving to drive IC
An upper case in which an illumination light source is arranged on the lower surface of the liquid crystal display element and a window is formed in an effective display area of the liquid crystal display element, and a lower case in which a concave portion for holding the illumination light source is formed. In the liquid crystal display device, the flexible substrate has a projection formed on the other side edge of the flexible substrate in a substantially perpendicular direction and provided with the connection terminal on the surface, and the projection is formed by the liquid crystal display. The connection terminal is folded upside down so that the connection terminal is connected to the connector of the interface board in a state where the connection terminal is folded on the back surface of the element, and the connection terminal portion does not overlap with the flexible board. With this configuration, a thin liquid crystal display device can be provided.

The projection J of the flexible substrate FPC2
The shape of T is not limited to the shape of the embodiment described later as long as the connection terminal portion is folded upside down without overlapping with the flexible substrate.

[0032]

Embodiments of the present invention will be described below in detail with reference to the accompanying drawings. FIG. 1 is a plan view of a main part schematically illustrating a configuration of a drain-side flexible substrate for explaining an embodiment of a liquid crystal display device according to the present invention. FIG. 2 is a plan view of the drain-side flexible substrate shown in FIG. FIG. 5 is a cross-sectional view of a principal part schematically illustrating a state where it is connected to an interface board. Note that the same reference numerals correspond to the same functional parts.

The drain-side flexible substrate FPC2 has a connection portion FSL for connecting to a drive IC mounted on the lower substrate SUB1 of the liquid crystal display element PNL, and is mounted on the interface substrate PCB at an end on the interface substrate PCB side. A protrusion JT2 for mounting a connection terminal CT4 for connecting to the connector CT2 formed is formed so as to protrude substantially perpendicularly from the longitudinal direction of the flexible substrate FPC2.

The protruding portion JT2 corresponds to the folding line BEN shown in FIG.
Folded in the back direction (arrow BENT) by TL, the connection terminal CT4 is positioned on the back side of the flexible board, and then the flexible board FPC2 indicated by the two-dot chain line is placed on the back side of the liquid crystal display element along the edge of the lower board SUB1. Bend. Then, the connection terminal CT of the flexible substrate FPC2
4 is an interface board PCB as shown in FIG.
To the connector CT2 from below.

Next, a specific example of a liquid crystal display device to which the above embodiment is applied will be described in detail. In the drawings described below, components having the same functions are denoted by the same reference numerals, and the description thereof will not be repeated.

FIGS. 3 and 4 are exploded perspective views for explaining an entire configuration example of the liquid crystal display device according to the present invention, and FIG. 3 covers a liquid crystal display element with an upper case constituting a housing of the liquid crystal display device. FIG. 4 is an exploded perspective view showing a previous state, and FIG. 4 is a diagram showing an upper case and an upper case in which an illumination light source (backlight) and various optical films laminated on the lower surface of the upper case and the liquid crystal display element shown in FIG. FIG. 4 is a developed perspective view showing a state before fixing.

3 and 4, SHD is an upper case (shield case), PNL is a liquid crystal display element, SPC
(SPC1 to SPC2) are insulating spacers, SCP-P is a protrusion of the spacer SPC (fitted into an opening formed in the upper case SHD), BAT is a double-sided adhesive tape, FPC1,
FPC2 is a multilayer flexible substrate (FPC1 is a gate-side substrate, FPC2 is a drain-side substrate), PCB is an interface substrate, SPS is a diffusion sheet, PRS is a prism sheet, GLB is a light guide, RFS is a reflector, G is a rubber cushion, MCA is the lower case (mold frame),
LP is a cold cathode fluorescent tube (CFL), LS is a light source reflector, L
PCH is a cable holder for a cold cathode fluorescent tube.

The shield case SH shown in FIG.
D is made by stamping and bending a single metal plate by a press working technique. WD is an opening that exposes the liquid crystal display element PNL to the field of view. In the liquid crystal display element PNL, a liquid crystal layer is sandwiched between two substrates, and a plurality of gate lines and drain lines arranged crosswise and thin film transistors are arranged at intersections of the gate lines and drain lines on the lower substrate. One pixel is composed of a pixel electrode driven by a thin film transistor.

The driving IC for driving the gate is a liquid crystal display element P
It is mounted on the lower board edge of the NL interface board PCB side, and supplies a drive signal to a drive IC for gate drive by the flexible board FCP1. A drive IC for driving the drain is mounted on the lower substrate on the side adjacent to the side on which the interface substrate is installed, and the flexible substrate FCP
2 supplies a drive signal to a drain drive IC.

Each of the above-described drive ICs and the flexible substrate F
The liquid crystal display device on which the CP1, the FCP2, and the interface substrate PCB are mounted is hereinafter referred to as a peripheral circuit mounted liquid crystal display device ASB.

A light guide GLB is provided on the inner periphery of the lower case MCA via a rubber cushion GC. Light guide GL
A reflector RFS is laminated on the back surface of B. On the upper surface of the light guide GLB, two prism sheets PRS (PR
S1, PRS2) and the diffusion sheet SPS are laminated, and the peripheral circuit-mounted liquid crystal display element ASB shown in FIG. 3 is mounted thereon, the upper case SHD is covered, and the fixed claws NL formed on the periphery of the upper case SHD are formed. A fixing recess formed in the lower case MCA is fitted and fixed, and a liquid crystal display device (also called a liquid crystal display module) is assembled.

Next, an example of the configuration of the liquid crystal display device according to the present invention will be described in more detail with reference to FIG. In addition,
Although there may be slight differences in the configuration of each drawing, it should be understood that this means that the present invention is applicable to a plurality of types of liquid crystal display devices.

FIG. 5 is an assembled view of the liquid crystal display device (liquid crystal display module), and is a front view and side views of the liquid crystal display element PNL viewed from the front side (ie, the liquid crystal display element PNL side). FIG. 6 is an explanatory diagram of an interface substrate on which the liquid crystal display module of FIG. 5 is mounted on the back surface and the side surface thereof.

The liquid crystal display module MDL has two types of storage / holding members, a lower case (mold frame) MCA and an upper case (shield frame SHD). H
LD is a personal computer with the module MDL as a display unit,
These are four mounting holes provided for mounting on an information processing device such as a word processor. A mounting hole HLD of the shield frame SHD is formed at a position corresponding to the mounting hole MH (shown enlarged in FIG. 18) of the mold case MCA (FIG. 5). Fix and implement. In the module MDL, a backlight inverter is arranged in the MI section (FIG. 9), and power is supplied to the backlight BL via the connection connector LCT and the lamp cable LPC.

Signals from the main computer (host) and necessary power are supplied to the interface connector CT1 on the interface board located on the back of the module.
To the controller section and the power supply section of the liquid crystal display module MDL via the.

FIG. 6B shows an interface substrate PC.
FIG. 4 is an explanatory diagram of a configuration example of B. The interface board PCB has a connector CT1 for receiving a signal from the main computer and a necessary power supply, and a low-voltage differential receiving circuit for converting a serial low-voltage differential signal received from the main computer into an original parallel signal. Chip LVDS,
A control circuit chip TCON, a digital / digital conversion circuit chip DD for generating various DC voltages, and a connector CT for connecting a gate-side flexible board FPC1 and a drain-side flexible board FPC2, which will be described later.
3 and CT2.

FIG. 7 shows a gate-side flexible substrate FPC1.
FIG. 9 is a plan view of relevant parts for explaining the arrangement of the drain-side flexible substrate FPC2. A driving IC for driving a gate is mounted on the upper surface of the liquid crystal display element PNL on the interface substrate side, and a gate-side flexible substrate FPC1 connected to the driving IC is arranged. Flexible board FPC
A drive IC for driving the drain is mounted on the lower side of the liquid crystal display element PNL adjacent to 1, and a flexible substrate FPC2 connected to the drive IC is arranged.

A protrusion JN4 is formed at the end of the flexible board FPC2 on the side of the gate-side flexible board FPC1, and a connector (flat connector) for connecting with the connector CT2 of the interface board PCB at the tip.
CT4 is provided, and the flexible substrate FPC2 is bent on the back surface of the liquid crystal display element PNL to connect the connector C
T4 is connected to connector CT2 of the interface board.

According to this embodiment, the connection portion between the interface substrate PCB and the flexible substrate FPC2 on the drain side is substantially flush with the flexible substrate FPC2.
Therefore, the overlapping of the drain-side flexible substrate FPC2 as described in the related art is eliminated, and the overall thickness of the liquid crystal display device is reduced by that much, and thinning can be promoted.

Next, a specific example of the liquid crystal display device according to the present invention will be described in detail. In the drawings described below, components having the same functions are denoted by the same reference numerals, and the description thereof will not be repeated.

FIG. 8 is an exploded perspective view for explaining another example of the overall configuration of the liquid crystal display device according to the present invention. SHD is an upper case (shield case), WD is a display window (hereinafter also simply referred to as a window), SPC1 to SPC4 are insulating spacers, FP
C1 and FPC2 are folded multilayer flexible circuit boards (FPC1 is a gate-side circuit board, FPC2 is a drain-side circuit board), PCB is an interface circuit board,
ASB is an assembled liquid crystal display device with a driving circuit board, PNL is a liquid crystal display device having a driving IC mounted on one of two superposed substrates (lower substrate), PR
S is a prism sheet (2 sheets), SPS is a diffusion sheet, G
LB is a light guide, RFS is a reflection sheet, MCA is a lower case (mold case) formed by integral molding, LP
Is a linear light source (cold cathode fluorescent tube), LPC1 and LPC2 are lamp cables, LCT is a connector for an inverter,
GB is a rubber bush for indicating a cold cathode fluorescent tube, and is stacked in the illustrated vertical arrangement to form an upper case SHD.
And a lower case MCA, and a liquid crystal display device (liquid crystal display module) is assembled. Details of other configurations will be described below.

FIG. 9 is an assembled view of the liquid crystal display module, which is a front view, a front side view, a right side view, and a left side view of the liquid crystal display element PNL viewed from the front side (that is, the upper side, the display side). .

FIG. 10 is an assembled view of the liquid crystal display module, and is a rear view of the liquid crystal display element PNL viewed from the rear side (ie, from below).

The liquid crystal display module MDL has two kinds of storage / holding members of a mold case MCA and a shield case SHD. The HDL is four mounting holes provided for mounting the module MDL as a display unit on an information processing device such as a personal computer or a word processor. At the position corresponding to the mounting hole MH of the molded case MCA (FIGS. 17 and 18 described later), the mounting hole HLD of the shield case SHD is provided.
Are formed (see FIG. 9), and fixed to and mounted on the information processing apparatus through screws and the like in both mounting holes. In the module MDL, the inverter for backlight is set to MI.
Connector LCT, lamp cable L
Power is supplied to the backlight BL via the PC.

Signals from the main computer (host) and necessary power are supplied to the controller and power supply of the liquid crystal display module MDL via the interface connector CT1 located on the back of the module.

FIG. 36 is a block diagram showing a TFT liquid crystal display element of the liquid crystal display module shown in FIG. 8 and circuits arranged on the outer periphery thereof. Although not shown, in this configuration example, the drain drivers IC _{1 to} IC _M are drain-side lead lines DTM formed on one substrate of the liquid crystal display element.
Further, chip-on-glass mounting (COG mounting) is performed using a gate-side lead line GTM and an anisotropic conductive film or an ultraviolet curable resin.

In this configuration example, the XGA specification 800
Corresponding to × 3 × 600 effective dots, M drain driver ICs and N gate driver ICs are COG mounted. The drain driver section 103 is disposed below the liquid crystal display element, the gate driver section 104 is disposed on the left side, and the controller section 101 and the power supply section 102 are disposed on the same left side. The controller section 101, the power supply section 102, the drain driver section 103, and the gate driver section 104 are interconnected by electrical connection means JN1 and JN2, respectively. Also, the controller unit 101
The power supply unit 102 is disposed on the back surface of the gate driver unit 104.

Next, the configuration of each component will be described in detail with reference to FIGS.

<< Metal Shield Case >> FIG. 9 shows an upper surface, a front side surface, a right side surface, and a left side surface of the shield case SHD. FIG. 3 is a perspective view of the shield case SHD viewed from obliquely above. .

Shield case (metal frame) SHD
Is manufactured by stamping and bending a single metal plate by a press working technique. An opening WD exposes the liquid crystal display element PNL to the field of view, and is hereinafter referred to as a display window.

Reference numeral NL designates, for example, 12 claws for fixing the shield case SHD and the mold case MCA. HK
Also, for example, six fixing hooks are provided, each of which is provided integrally with the shield case SHD. The fixing claws NL shown in FIG. 8 and FIG. 9 store the liquid crystal display element ABS with the driving circuit in the shield case SHD with the spacer SPC interposed therebetween in a state before bending, and are bent inward to form the molded case MCA. It is inserted into the provided square fixing recess NR (see each side view in FIG. 17) (see FIG. 5 for the folded state).

The fixing hooks HK are fitted into fixing projections HP (see the side view in FIG. 17) provided on the mold case MCA. Thereby, the shield case SHD for holding and storing the liquid crystal display element ABS with the drive circuit
And a molded case MCA that holds and stores the light guide GLB, the cold cathode fluorescent lamp LP, and the like. Further, a thin and long rectangular rubber cushion is provided around four edges of the lower surface of the light guide GLB (the rear surface of the reflection sheet) (see FIGS. 32 to 35 described later).

Also, the fixing claw NL and the fixing hook HK
Extend the bending of the fixing claws NL and fix the fixing hooks H
Since the removal is easy only by removing the K, the repair is easy and the replacement of the cold cathode fluorescent tube of the backlight BL is also easy. Further, in this configuration example, as shown in FIG. 4, one side is mainly fixed by the fixing hook HK, and the opposite side is fixed by the fixing claw NL, so that all the fixing claws NL are fixed. Can be disassembled simply by removing some of the fixing claws NL. Therefore, repair and replacement of the backlight are also easy.

The CSP is a through hole, and the relative position between the shield case SHD and other parts is accurately set by inserting the through hole CSP into the pin which is fixed and erected at the time of manufacturing, and mounting the shield case SHD. It is for. The insulating spacers SPC1 to SPC4 are coated with an adhesive on both surfaces of the insulating material, so that the shield case SHD and the liquid crystal display element with drive circuit ABS can be reliably fixed with the spacing between the insulating spacers. When the module MDL is mounted on an application product such as a personal computer, the through-hole CSP
Can be used as a reference for positioning.

<< Insulating Spacer >> As shown in FIGS. 8 and 32 to 35, the insulating spacer SPC (SPC1 to SPC
4) not only secures insulation between the shield case SHD and the liquid crystal display element ABS with a drive circuit, but also ensures positional accuracy with the shield case SHD and double-sided adhesive tape between the liquid crystal display element ABS with a drive circuit and the shield case SHD. B
It is fixed by AT.

<< Multilayer Flexible Board FPC1, FPC
2 >> FIG. 11 is a front view of a liquid crystal display device with a drive circuit board in which a gate-side flexible substrate FPC1 and a drain-side flexible substrate FPC2 before bending are mounted on the outer periphery of the liquid crystal display device PNL.

FIG. 12 shows an interface circuit board PCB.
12 is a rear view of the liquid crystal display device with a drive circuit board of FIG.

FIG. 13 shows that after the flexible boards FPC1, FPC2, and the interface circuit board PCB are mounted under the shield case SHD, the flexible board F
FIG. 9 is a rear view showing a state in which the liquid crystal display element PNL is housed in the shield case SHD by bending the PC2.

The left IC chip in FIG. 11 is a driving IC chip on the vertical scanning circuit side, and the lower IC chip is a driving IC chip on the video signal driving circuit side, and is an anisotropic conductive film (A in FIG. 30).
It is COG mounted on the substrate using CF2) or an ultraviolet curing agent.

In the conventional method, a tape carrier package (TCP) in which a driving IC chip is mounted by a tape automated bonding method (TAB) is connected to a liquid crystal display element PNL using an anisotropic conductive film. CO
In the G mounting, since the direct drive IC is used, the above TA
The process B is not required, the process is shortened, and the tape carrier is not required. In addition, CO
G mounting is suitable as a mounting technology for a high-definition and high-density liquid crystal display element.

Here, drain driver ICs are arranged in a line on one long side of the liquid crystal display element PNL, and a drain line is drawn out on one long side. The gate lines are also drawn out to one short side, but when the definition is further improved, the gate lines can be drawn out to two opposing short sides.

In the method of alternately drawing out the drain line or the gate line, the drain line DTM or the gate line GT is used.
The connection between M and the output-side bumps BUMP of the drive IC is facilitated, but it is necessary to dispose the peripheral circuit board on the outer periphery of two long sides of the liquid crystal display element PNL opposed to each other. For this reason, there is a problem that the external dimensions are larger than in the case of single-sided drawer. In particular, when the number of display colors increases, the number of data lines of display data increases and the outermost dimension of the information processing apparatus increases. In this configuration example, the drain line is drawn out to only one side using a multilayer flexible substrate. I have to.

FIGS. 21A and 21B are explanatory views of a multilayer flexible substrate FPC2 for driving a drain driver, wherein FIG. 21A is a back (lower) view and FIG. 21B is a front (upper) view. The flexible substrate FPC2 is a multilayer printed circuit board using a polyimide film and extends along the edge of the lower substrate SUB2 of the liquid crystal display element PNL on which the drain drive IC is mounted. Is formed. In this embodiment, the number of drain drive ICs is one.
Although the number is shown as zero, the number increases as the definition of the liquid crystal display element increases.

At one end of the flexible board FPC2 (the end on the side adjacent to the interface board), there is provided a protrusion JT2 projecting substantially perpendicularly to the longitudinal direction of the flexible board. A connection terminal CT4 for connecting to a connector CT2 mounted on the interface board is mounted on the front side. The connection terminal CT4 is formed of a terminal row, but may be a connector component similar to the CT2.

Then, the convex portion JT2 is bent to the rear surface of the interface board PCB in the folding structure described with reference to FIG. That is, the flexible substrate FPC2 first folds the convex portion JT2 in the BENT1 direction as shown in FIG. 28, and then, as in BENT2, the back surface of the liquid crystal display element (the back surface of the interface substrate: not shown in FIG. 28).
The connector CT2 is connected to the connection terminal CT4 as shown in FIG.

FIG. 23 is an explanatory view of a multilayer flexible substrate FPC1 for driving a gate driver.
(A) is a back (lower) view, and (b) is a front (upper) view.

FIG. 27 is a structural explanatory view of the multilayer flexible substrate FPC2 shown in FIG. 21.
(A) is a sectional view taken along line AA ', (b) is a sectional view taken along line B-
FIG. 3C is a cross-sectional view along the line B ′, and FIG. 3C is a cross-sectional view along the line CC ′. For the sake of explanation, the ratio of the dimension in the thickness direction and the dimension in the plane direction in FIG. 27 differs from the actual dimension and is exaggerated.

FIG. 24 is a schematic wiring diagram showing the connection relationship between the signal wiring in the multilayer flexible substrate FPC and the input signal to the driving IC on the substrate SUB1. The signal wiring in the multilayer flexible substrate FPC includes a first wiring group parallel to one side of the substrate SUB1 and a second wiring group perpendicular to the one side of the substrate SUB1. The first wiring group is a common wiring group for supplying a common signal between the driving ICs, and the second wiring group is a wiring group for supplying a signal required for each driving IC. Therefore, at least the partial FSL is 1
It is composed of multiple conductor layers. Further, the partial FML is composed of at least two conductor layers, and it is necessary to electrically connect the first wiring group and the second wiring group with through holes. In this configuration example, it is necessary to reduce the short side length of the portion FML to a length that does not touch the end of the lower deflection plate when bent.

That is, as shown in FIG. 27, three or more conductor layers, for example, eight conductor layers L1 to L in this configuration example.
8 is provided in parallel with one side of the liquid crystal display device PNL, and peripheral circuit wiring and electronic components are mounted on this portion, so that the number of layers can be maintained while maintaining the external dimensions of the substrate even when the number of data lines increases. Can be dealt with by increasing.

The conductor layer L1 is for component pad, ground, L
2 is for a gray scale reference voltage _Vref , 5V (or 3.3V) power supply, L3 is for ground, L4 is for data signals and clocks CL2 and CL1, L5 is for lead-out wiring which is the second wiring group, and L6 is for gradation reference voltage V _ref, L7 is a data signal, L8 is 5V (or, 3.3V) power supply.

The connection between the conductor layers is made through holes VIA (FIG. 2).
9 (a)). Conductor layer L
1 to L8 are formed of copper Cu wiring, and input terminal wiring Td to the drive IC of the liquid crystal display element PNL (FIGS. 25 and 2).
6), a portion of the conductive layer L5 is further plated with gold Au on a nickel-Ni underlayer on copper Cu.
Therefore, the connection resistance between the output terminal TM and the input terminal wiring Td can be reduced.

Each of the conductor layers L1 to L8 has an intermediate layer made of a polyimide film BFI as an insulating layer, and the conductor layers are fixed by an adhesive layer BIN. The conductor layer is covered with an insulating layer except for the output terminal TM, but the multilayer wiring portion F
In the ML, a solder resist SRS is applied to the uppermost and lowermost layers to secure insulation. Further, an insulating silk material SLK is attached to the outermost surface.

The advantage of the multilayer flexible substrate is that the conductor layer L5 including the connection terminal portion TM necessary for COG mounting is provided.
Can be integrally formed with other conductor layers, and the number of parts is reduced.

In addition, by forming a portion FML of three or more conductor layers, a hard portion with little deformation can be provided, and a positioning hole FHL can be arranged in this portion. Even when bending the multilayer flexible substrate, reliable and accurate bending can be performed without deformation at this portion. Further, as will be described later, the solid shape or, for example, a diameter of 200
A mesh-shaped conductor pattern ERH (see FIG. 29 (a)) provided with a large number of fine holes ESH having a size of about m can be arranged on the surface layer L1, and the remaining two or more conductor layers can be used as conductor patterns for component mounting and peripheral wiring. Wiring can be performed.

The protruding portion FSL does not need to be a single conductor layer, and the protruding portion FSL may be composed of two conductor layers. In this configuration, when the pitch of the input terminal wiring Td to the driving IC becomes narrow, the patterns of the terminal wiring Td and the connection terminal portion TM are formed in a staggered pattern in a plurality of rows of wiring groups. Or the like, and when the connection terminal portion TM in the first conductor layer is pulled out, the wiring group in one row meets the through hole VIA and is connected to the multilayer second conductor layer. When a part of the peripheral wiring is arranged on the second conductor layer in the protruding portion FSL, the configuration of the second conductor layer is effective.

As described above, by forming the protruding portion FSL with two or less conductor layers, heat transfer is good at the time of thermocompression bonding by heat sealing, pressure can be applied uniformly, and the connection terminal portion TM and the terminal The reliability of the electrical connection of the wiring Td can be improved. Also, when bending a multilayer flexible substrate,
Bending with high accuracy can be performed without applying bending stress to the connection terminal portion TM. Further, since the protruding portion FSL is translucent, the pattern of the conductor layer can be observed from the upper surface side of the multilayer flexible substrate, so that there is an advantage that a pattern inspection such as a connection state can be performed from the upper surface side. In addition,
JT2 in FIG. 21 is a drain-side flexible substrate FPC2.
A concave portion for electrically connecting the circuit board and the interface circuit board PCB, CT4 is a flexible substrate FPC2 provided at the tip of the convex portion JT and the interface circuit board PCB
This is a flat type connector for electrically connecting the power supply and the power supply.

FIG. 22 is an explanatory view of a main part of the multilayer flexible printed circuit FPC2. FIG. 22 (a) is an enlarged detailed view of a portion J in FIG. 21 (a), and FIG. 22 (b) shows the mounting and folded state of the multilayer flexible FPC2. It is a side view.

[0088] In FIG. 22 (a), P _X is the wave of the wavelength of the polyimide film BFI end wavy, P _Y its wave height (amplitude × 2 wave), P ₁ is connecting the mountain each other wave linear (Referred to as a wave peak line), and P ₂ is a straight line connecting the wave valleys (referred to as a wave valley line). LY2 is (referred to as connection length) length of the connection portion of the substrate SUB1 of the multilayer flexible substrate FPC2, LY1 is the length between the connection portion and mountain line P ₁ of the wave with the substrate SUB1 of the multilayer flexible substrate FPC2 is there.

The drain-side flexible substrate FPC2 is
As shown in FIG. 22B, one end of the liquid crystal display element PN
The terminal of the drain line at the end of SUB1 of L (FIGS. 25 and 2)
No. 6 Td) via an anisotropic conductive film ACF, folded back at the middle of the wave height P _Y outside the edge, and the multilayer wiring portion FML at the other end is disposed on the lower surface of SUB1, It is stuck on the lower surface of SUB1 by a tape BAT. Note that the numbers 1 to 45 assigned to the output terminal TM in FIG. 23B correspond to the numbers 1 to 45 assigned to the terminal Td in FIG. 25 and FIG. 26, and via the anisotropic conductive film ACF1. Electrically connected.

As described above, in this configuration, the signal input flexible substrate FPC2 whose one end is connected to the end of the substrate SUB1 of the liquid crystal display element and the other end is folded back on the lower surface (or upper surface) of the substrate SUB1. By forming the end of the polyimide film BFI of the projecting portion FSL into a wavy shape (or a shape having peaks and valleys such as a sawtooth shape) along the bending line direction, the end of the polyimide film BFI at the bent portion is formed. , And a good bending curve (R) can be provided at the bent portion, the occurrence of disconnection can be suppressed, and the reliability can be improved.

In this configuration example, the multilayer flexible substrate FPC1 on the gate side has three conductor layers, and L1 is V
_dg (10V), V _sg (5V), V _ss (ground), L
2 is a lead wiring, clock CL3, FLM, V _dg (1
0 V), L3 is V _EG (-10 to -7 V), V _EE (-1
4 V), V _SG (5 V), and common voltage V _com .

Next, the alignment marks ALMG (FIG. 23A) on the multilayer flexible substrate and ALMD (FIG.
2 (a)) will be described.

In the multilayer flexible substrates FPC1 and FPC2 shown in FIGS. 21 to 23, the length of the output terminal TM is usually designed to be about 2 mm in order to secure connection reliability. However, since the long sides of the flexible substrates FPC1 and FPC2 are long, a positional shift including slight rotation in the long axis direction may cause a positional shift between the input terminal wiring Td and the output terminal TM, resulting in a connection failure. . Liquid crystal display element PN
The alignment between the L and the flexible substrates FPC1 and FPC2 is performed by inserting the holes FHL opened at both ends of each substrate into the fixing pins and then aligning the input terminal wiring Td and the output terminal TM at several places. However, in order to further improve the accuracy, two alignment marks ALMG and ALMD are provided for each protruding portion FSL.

In the present configuration example, in order to improve connection reliability, a dummy line NC is provided at a position adjacent to a predetermined number of input terminals TM, and a square-shaped alignment mark ALMG is formed on the dummy line by a pattern. The connection is performed, and the square filling pattern (on the drain side, see ALC in FIGS. 25 and 26) on the opposing substrate SUB1 is positioned so as to be exactly contained in the square.

The common voltage is applied from the conductive beads or paste to the substrate S through the pattern of the wiring Td on the substrate SUB1.
It is supplied to the common transparent pixel electrode COM on the UB2 side.

The alignment mark ALMG is provided in pattern connection with a terminal electrically connected to the common transparent pixel electrode COM, and is aligned with a square filling pattern ALD (see FIG. 26) on the substrate SUB1. Further, in this configuration example, a joint pattern (not shown) for connecting to the flexible substrate FPC1 of the gate driver is provided at the lower end of the flexible substrate FPC2 of the drain driver in FIG.

Next, the shape of the conductor layer portion FSL of two or less layers will be described.

FS composed of a single-layer or two-layer conductor wiring
The projecting shape of L was a convex shape separated for each driving IC. Thus, the pitch P _G and P _D terminal TM vary thermal expansion multilayer flexible substrate in the longitudinal direction at the time of thermocompression bonding of a heat tool, it is possible to prevent the phenomenon of peeling or poor connection occurs between the connection terminals Td. That is, the driving IC
It can be a thermal expansion amount corresponding to the length of the pitch P _G and P _D cycle of each even driver IC shift by up to a terminal TM by a separate convex shape for each. In this configuration example, the multilayer flexible substrate is formed into a convex shape divided into 10 in the major axis direction, the amount of thermal expansion can be reduced to about 1/10, which contributes to relaxation of application to the terminal TM, and The reliability of the liquid crystal display module MDL can be improved.

As described above, the alignment mark ALM
G and ALMD, and drive the protruding shape of the portion SL.
By forming the convex shape separated for each C, even if the number of connection wirings or the number of display data increases, the peripheral driving circuit can be reduced with high accuracy while ensuring connection reliability.

Next, three or more conductor layer portions FML will be described.

Chip capacitors CHG and CHD are mounted on the conductor layer portion FML of the FPC1 and FPC2. That is, in the gate-side multilayer flexible substrate FPC1, the chip capacitor CHG is soldered between the ground potential V _SS (0V) and the power supply V _dg (10V) or between the power supply V _sg (5V) and the power supply V _dg . Further, in the flexible substrate FCP2 on the drain side B, the ground potential V _SS
And the power supply V _dd (5 V or 3.3 V) or between the ground potential _VSS and the power supply V _dd
Is soldered. These capacitors CHG and CHD are for reducing noise superimposed on the power supply line.

In this configuration example, the above chip capacitor C
The HD was soldered only to one surface conductor layer L1 and was designed to be located entirely below the substrate SUB1 after bending. Therefore, it is possible to mount the power supply noise smoothing capacitor on the flexible substrates FPC1 and FPC2 while keeping the thickness of the liquid crystal display module MDL constant.

Next, a method for reducing high-frequency noise generated from an information processing apparatus equipped with a liquid crystal display device will be described.

Since the shield case SHD side is the front side of the liquid crystal display module MDL and the front side of the information processing apparatus, the generation of EMI (electromagnetic interference) noise from this side depends on the usage environment for external devices. It creates big problems. For this reason, in this configuration example, the surface layer L1 of the conductor portion FML is covered with a solid or mesh pattern ERH of a DC power supply as much as possible.

FIGS. 29 (a) and 29 (b) are explanatory views of the conductor pattern of the multilayer wiring portion. FIG. 29 (a) is a plan view showing the configuration of the surface conductor layer pattern of the multilayer wiring portion FML in a part of FIG. 21 (b). ) Shows a partially enlarged view of the interface circuit board PCB shown in FIG.

The mesh MESH is composed of a large number of holes of about 300 μm opened in the surface conductor layer L1, and the mesh pattern ERH is formed by the through holes VIA and the capacitors CHD.
It covers almost the entire surface except for parts.

<< Interface Circuit Board PCB >> FIG.
1 is an explanatory view of an interface circuit board having a controller section and a power supply section, and FIG.
(B) is a partial front side view of the mounted hybrid integrated circuit HI, and (c) is a front (top) view.

In this configuration example, a multilayer printed circuit board made of a glass epoxy material was used for the interface circuit board PCB (hereinafter simply referred to as the board PCB). It should be noted that a multilayer flexible substrate can be used, but since this portion did not employ a bent structure, a multilayer printed circuit board was used which was relatively inexpensive.

All the electronic components are mounted on the lower surface side of the substrate PCB, which is the back surface side when viewed from the information processing apparatus side. One integrated circuit element TCON is disposed on the substrate for the display control device. The integrated circuit element TCON is not housed in a package, and is directly mounted on a circuit board PCB by using a ball grid array (Ball Grid Array).
y) It is implemented.

The interface connector CT1 is connected to the substrate P
It is located substantially at the center of the CB, and further includes a plurality of resistors, capacitors, circuit components EMI for removing high-frequency noise, and the like.

The hybrid integrated circuit HI is formed by hybridizing a part of the circuit and mounting a plurality of integrated circuits and electronic components mainly for forming a power supply on the upper and lower surfaces of a small circuit board. PCB
One is mounted above.

The electrical connection through the electrical connection means JN1 between the flexible substrate FPC1 as the gate driver substrate and the interface circuit substrate PCB uses the connector CT3 in this configuration.

FIG. 32 is a cross-sectional view taken along the line AA ′ of FIG. 5, FIG. 33 is a cross-sectional view taken along the line BB ′, FIG. 34 is a cross-sectional view taken along the line CC ′, and FIG. This corresponds to a cross-sectional view taken along line D '.

As shown in FIG. 32, the liquid crystal display element PN
When viewed from a direction perpendicular to the substrates SUB1 and SUB2 constituting L, the interface circuit substrate PCB is overlapped with the liquid crystal display element PNL, and is disposed below the lower surface of SUB1. Further, one end of the flexible substrate FPC1 for the gate driver has a liquid crystal display element PN.
L directly and mechanically connected to the substrate SUB1 of L,
Unlike the drain side, almost the entire width is superimposed on the interface circuit board PCB without bending.

As described above, the interface circuit board P
By partially overlapping the CB with the substrate SUB1 of the liquid crystal display element PNL and further arranging the gate driver circuit board FPC1 on the interface circuit board PCB, the width and area of the frame portion can be reduced, and the liquid crystal display can be reduced. The external dimensions of the device and an information processing device such as a personal computer or a word processor incorporating the liquid crystal display device as a display portion can be reduced.

Liquid crystal display element PNL and shield case SH
D is provided with a spacer SPC made of resin or the like between the substrate SUB1 below the liquid crystal display element PNL, and is fixed above and below it with a double-sided adhesive tape BAT interposed therebetween.

A plurality of openings HOLS are formed in the shield case SHD in the longitudinal direction, and the protrusion SPC2-P formed on the spacer SPC is fitted to prevent the spacer SPC from shifting.

<< Liquid crystal display element ABS with drive circuit board >>
As shown in FIG. 33, a flexible substrate F for a drain driver is provided on the side opposite to the pattern forming surface of the substrate SUB1.
PC2 is bent and adhered. Polarizing plates POL1 and POL2 are located slightly (about 1 mm) outside the effective display area AR, and the end of the FPC 2 is located about 1 to 2 mm away therefrom.

The distance from the end of the substrate SUB1 to the tip of the protrusion of the bent portion of the FPC2 is as small as about 1 mm,
Compact mounting becomes possible. Therefore, in the present configuration example, the distance from the effective display area AR to the tip of the protrusion of the bent portion of the FPC 2 was about 7.5 mm.

FIG. 28 is a perspective view for explaining a method of bending and mounting a multilayer flexible substrate. The connection between the flexible substrate FPC2 for the drain driver and the flexible substrate FPC1 for the gate driver is performed by using a FP as a joiner.
A connection terminal (here, a flat connector) provided at the tip of a convex portion JT2 formed of a flexible substrate integrated with C2.
Use CT4.

The connection terminal CT4 is provided on the surface side of the convex portion JT2, and is first folded around the line BTL in the BENT1 direction, and then folded in the BENT2 direction to be connected to the connector CT2 of the interface board PCB (see FIG. 34). Is as described above. Note that the FPC2 and the substrate SUB1 are fixed by inserting a double-sided adhesive tape between the FPC2 and the substrate SUB1.

<< Rubber Cushion GC >> Rubber Cushion G
C is a reflection sheet and a mold case M provided on the lower surface of the light guide GLB as shown in FIGS. 4 and 32 to 35.
The light guide GLB and the liquid crystal display element PNL are fixed between the shield case SHD and the mold case MCA by utilizing the elasticity thereof. Note that the rubber cushion GC is installed around the light guide GLB, or may be inserted only into the engaging portion between the claws NL formed on the shield case SHD and the mold case MCA.

At least one surface of the rubber cushion GC is provided with an adhesive or a double-sided adhesive tape.
B and one of the molded cases MCA are attached to the other and fixed.

<< Backlight BL >> As shown in FIG. 32, the backlight BL is composed of a light guide GLB, an optical sheet member including a diffusion sheet SPS and a prism sheet PRS disposed on the upper surface thereof, and a lower surface of the light guide GLB. Sheet RFS installed in the light source, a linear light source (cold cathode fluorescent tube) LP installed along one end surface of the light guide GLB, and a light source reflector LS
It is composed of Each of these members is a mold case M
It is stored in the recess of CA.

The light source reflector LS is installed above the linear light source LP along the longitudinal direction, and is fixed to the edge of the light guide GLB (on the prism sheet PRS) and the edge of the mold case MCA with a double-sided adhesive tape BAT. ing.

In the configuration example, the reflection sheet RFS provided on the lower surface of the light guide GLB is extended to a position below the linear light source LP, and the extended portion RFS-E is used as a lower light source reflector. However, the lower light source reflector is not always necessary, and it is sufficient that the inner surface of the mold case MCA is light reflective (mirror surface or white). Further, the linear light source L
A linear light source L is provided on the inner wall side opposite to the light guide GLB of P.
Even if the light from P is reflected, most of the light is blocked by the linear light source and is not used, so there is no need to install a reflector,
Linear light source LP and reflector LS or molded case MC
When the gap on the lower surface of A becomes large, the light utilization rate can be improved by making the inner wall (including the bottom surface) of the mold case MCA light-reflective (mirror surface or white).

FIG. 14 is a front view of the backlight BL (the liquid crystal display element PNL side), FIG. 15 is a front view of the backlight of FIG. 14 with the prism sheet PRS and the diffusion sheet SRS removed, and FIG. FIG. 16 is a front view similar to FIG.

The lamp cables LPC (LPC1, LPC2) of the cold cathode fluorescent tubes, which are linear light sources LP, are wired on the side surfaces of the liquid crystal display element PNL, and are supplied with power from a not-shown inverter power supply board via a lamp connector LCT. GB is a rubber bush that holds the lamp cable LPC.

<< Diffusion Sheet SPS >> Diffusion Sheet SPS
Is mounted on the light guide GLB and diffuses light emitted from the upper surface of the light guide GLB to uniformly certify the liquid crystal display element PNL.

<< Prism Sheet PRS >> The prism sheet PRS is composed of two sheets in this configuration example, and is a diffusion sheet SPS.
Are placed on top of each other, and each prism sheet having a smooth lower surface and a prism surface as an upper surface is arranged so that the prism grooves are perpendicular to each other. This prism sheet P
RS transmits light from the diffusion sheet SPS to the liquid crystal display element PNL.
Light is collected in the direction to improve the brightness of the backlight BL.
As a result, the power consumption of the backlight can be reduced, and the size and weight of the liquid crystal display module can be reduced.

Diffusion sheet SPS and prism sheet PRS
Are provided with two fixing small holes SLV whose positions coincide with each other at the time of installation of the sheet, and a pin-shaped protrusion M is formed at the corresponding one end of the mold case MCA.
A PN is formed, and both are inserted and aligned via the sleeve SLV. The sleeve SLV is made of, for example, an elastic body such as silicon rubber, and has an inner diameter smaller than an outer diameter of the convex portion MPN, thereby preventing the sleeve SLV from falling off.

Note that, as shown in FIG.
On the side opposite to P, the diffusion sheet S is attached to a pin-shaped projection MPN integrally provided at one side end of the mold case MCA.
By inserting and positioning the small holes provided in the PS and the prism sheet PRS, more accurate positioning can be performed.

The projection MPN is located below the flexible board FPC1 on the gate side and at a position not overlapping the circuit board PCB in a plan view, so that the thickness of the liquid crystal display module is not increased.

<< Molded Case MCA >> FIG. 17 is an explanatory view of the molded case MCA, and FIG.
It is an enlarged view of a part, a B part, a C part, and a D part. A molded case MCA, which is a lower case formed by molding, includes a cold cathode fluorescent tube LP, a lamp cable LPC, and a light guide GLB.
This is a backlight storage case that holds the etc., and is made by integral molding with one mold of synthetic resin.

The mold case MCA is tightly united with the metal shield case SHD by the action of each fixing member and the elastic body, and the vibration resistance of the liquid crystal display module MDL is improved.
Thermal shock resistance can be improved and reliability is improved.

On the bottom surface of the mold case MCA, a large opening MO occupying at least half the area of the bottom surface is formed at a central portion excluding the peripheral frame portion. Thereby, after assembling the mold case NCA, the backlight B
Rubber cushion GC between L and mold case MCA
Is applied to the bottom surface of the mold case MCA vertically from the upper surface to the lower surface by the action of the mold case MCA.
The bottom surface of the CA can be prevented from swelling, the increase in the maximum thickness is suppressed, and the thickness and weight of the liquid crystal display module MDL can be reduced.

The MCL in FIG. 17 is a cutout provided in the mold case MCA at a location corresponding to the mounting portion of the power supply circuit DC-DC converter DD shown in the heat-generating components (FIGS. 12 and 31) of the interface circuit board PCB. Notch (including notch for connecting connector CT1).

As described above, by providing the cutout without covering the heat generating portion on the circuit board PCB with the mold case, the heat radiation of the heat generating portion of the interface circuit board PCB can be improved. In addition, the integrated circuit TCON for display control is also considered to be a heat-generating component, and the molded case MCA thereon may be cut away.

[0139] MH in FIG. 17 is a value for attaching the liquid crystal display module MDL to an application device such as a personal computer.
Mounting holes. The shield case SHD is also provided with a mounting hole HLD corresponding to the mounting hole MH of the mold case MCA, and is fixed and mounted on an application device using screws or the like.

In FIGS. 17 and 18, MB is the light guide GL.
B is a holding part, and PJ is a positioning part. MC1
Reference numeral 4 denotes a housing for the lamp cables LPC1 and LPC2.

<< Storing Light Guide GLB in Mold Case MCA >> FIG. 19 shows the mold case MCA of the light guide GLB.
5A is a plan view of a main part, FIG. 5B shows a conventional structure of a corner portion of FIG. 5A, and FIG. 5C shows a structure of the present configuration example of a corner portion.

As shown in FIG. 19A, the light guide GL
The four corners of B are provided with straight bevels which are chamfered.
A linear oblique positioning portion PJ is also formed at A. Conventionally, as shown in (b), since the corner portion is at a right angle, the light guide GLB, which is a weak component against the force F in the side direction (y direction) of the light guide GLB and is heavy, is subject to vibration and impact. As a result, the positioning portion PJ was sometimes damaged.

In this configuration example, as shown in FIG. 19 (c), the light acting on the positioning portion PJ is dispersed in two directions fx and fy by forming the light guide GLB and the positioning portion PJ in an oblique shape. In addition, the positioning portion PJ can be prevented from being damaged, and the reliability is improved.

<< Arrangement of Cold Cathode Fluorescent Tube LP and Light Source Reflecting Plate LS >> As shown in FIG. 19A, the light source reflecting plate LS is provided above the linear light source (cold cathode fluorescent tube) LP by a light guide. G
The LB and the mold case MCA are bridged and fixed using a double-sided adhesive tape. The cross-sectional structure of this part is shown in FIG.

As shown in FIG. 32, the cold cathode fluorescent lamp LP as a linear light source is installed close to one end surface of the light guide GLB, and above the light source reflector LS, a double-sided adhesive tape BA.
Fixed at T.

In FIG. 14 to FIG. 17, the cold cathode fluorescent lamp LP constituting the backlight BL is a liquid crystal display module MDL.
Are arranged on the long side and below the display area. That is, as shown in FIGS. 42 and 43, when mounted on an information processing device such as a personal computer or a word processor, the cold cathode fluorescent lamp LP is located below the long side of the display unit. In the example shown in FIGS. 14 and 15, the inverter IV is arranged in the inverter storage section MI in the display section, and the lamp cable LPC1 is connected to the left and upper 2 of the liquid crystal display module MDL.
The lamp cable LPC2 is wired along the right side.
Wired along the sides. On the other hand, in the example shown in FIG.
Shows a case where the inverter IV is arranged in the keyboard,
The lamp cable LPC1 is wired along three sides of the left, upper, and right sides of the liquid crystal display module MDL, and both lamp cables LPC1 and LPC2 extend from the lower right.

By arranging the cold cathode fluorescent lamps LP below the display section of the liquid crystal display module MDL as shown in FIG.
When the inverter IV is arranged in the keyboard section as shown in FIG.
The length of the PC 2 can be shortened, the impedance causing noise and a change in waveform can be reduced, and the startability of the cold cathode fluorescent lamp LP can be improved. In addition,
When the inverter IV is arranged on the keyboard side, the width of the display unit can be further reduced. Furthermore, a cold cathode fluorescent tube LP
Is arranged below the display unit, the shock caused by opening and closing the display unit is reduced, and the reliability is improved. Then, since the center of the display surface of the liquid crystal display element PNL shifts upward,
There is also an effect that it is possible to prevent a hand striking the keyboard by the user from being difficult to see below the display screen.

In the above configuration, the cold-cathode fluorescent lamp LP is installed below the long side of the liquid crystal display element PNL. However, it goes without saying that it can be installed above the long side or the short side.

FIG. 36 is a block diagram illustrating a circuit configuration of a liquid crystal display element PNL and a drive circuit and the like arranged on the outer periphery thereof. In this configuration, a thin film transistor (TFT)
Driver section 103 is arranged only below the liquid crystal display element PNL (TFT-LCD), and has a size of 800 × 600.
A gate driver unit 104, a controller unit 101,
A power supply unit 102 is provided.

The drain driver section 103 is mounted by bending the above-mentioned multilayer flexible substrate. The interface board PCB on which the controller unit 101 and the power supply unit 102 are mounted is arranged on the back surface of the gate driver unit 104 arranged on the outer periphery of the short side of the liquid crystal display element PNL. This is because the width of the information processing apparatus is limited, and it is necessary to reduce the width of the liquid crystal display module MDL constituting the display unit as much as possible.

As shown in FIG. 37, the thin film transistor TFT is arranged in an intersection region between two adjacent drain signal lines DL and two adjacent gate signal lines GL. A drain electrode and a gate electrode of the thin film transistor TFT are respectively connected to a drain signal line DL and a gate signal line GL.
Connected to.

Since the source electrode of the thin film transistor TFT is connected to the pixel electrode, and a liquid crystal layer is provided between the pixel electrode and the common electrode, a liquid crystal capacitance (C _LC ) is provided between the thin film transistor TFT and the source electrode of the thin film transistor TFT. Connected equivalently. The thin film transistor TFT becomes conductive when a positive bias voltage is applied to the gate electrode, and becomes non-conductive when a negative bias voltage is applied. A storage capacitor C _add is connected between the source electrode of the thin film transistor TFT and the previous gate signal line.

It should be understood that the source electrode and the drain electrode are originally determined by the bias polarity between them, and in this liquid crystal display device, the polarity is inverted during the operation, so it should be understood that the source electrode and the drain electrode are switched during the operation. However, in the following description, one is fixed as a source electrode and the other is fixed as a drain electrode for convenience.

FIG. 40 is a block diagram showing a schematic configuration of each driver (drain driver, gate driver, common driver) of the liquid crystal display element and a signal flow. The display control element 201 and the buffer circuit 210 are provided in the controller unit 101 shown in FIG.
Are provided in the drain driver unit 103 shown in FIG.
The gate driver 206 is the gate driver unit 10 shown in FIG.
4.

The drain driver 211 comprises a data latch section for display data and an output voltage generating circuit. Further, the gradation reference voltage generator 208 and the multiplexer 20
9, common voltage generation unit 202, common driver 203,
Level shift circuit 207, gate-on voltage generator 20
4. The gate-off voltage generation unit 205 and the DC-DC converter 212 are provided in the power supply unit 102 shown in FIG.

FIG. 39 is a diagram showing the levels of the common voltage, the drain voltage, and the gate voltage and their waveforms. The drain waveform shows a waveform in black display.

FIG. 38 is an explanatory diagram of the flow of display data and clock signals for the gate driver 206 and the drain driver 211. FIG. 41 is a timing chart showing display data input from the main computer (host) to the display control device 201 and signals output from the display control device 201 to the drain driver and the gate driver.

The display control device 201 controls the control signals (clock signal, display timing signal,
(A synchronization signal), a clock D1 (CL1), a shift clock D
2 (CL2) and display data, and at the same time, a frame start instruction signal FLM, a clock G (CL3) and display data as control signals to the gate driver 206.

The carry output of the preceding stage of the drain driver 211 is directly used as the drain driver 211 of the next stage.
Carry input.

As is apparent from FIG. 41, the shift clock signal D2 (CL2) of the drain driver is the same as the frequency of the clock signal (DCLK) and display data input from the main body computer, and is about 40 MHz in the XGA display element. And the EMI countermeasures become important.

<< Information Processing Device Mounted with Liquid Crystal Display Module MDL >> FIGS. 42 and 43 are perspective views of a notebook personal computer or a word processor mounted with the liquid crystal display module MDL, respectively. As described above, FIG. 42 shows the inverter IV as a display unit, that is, a liquid crystal display module MD.
FIG. 43 shows a case where it is arranged in the keyboard unit, and FIG. 43 shows a case where it is arranged in the L inverter storage unit MI (see FIGS. 14 and 17).

A signal from the information processing device first goes from a connector located substantially at the center of the left interface substrate PCB to the display control integrated circuit element TCON, and the converted display data is sent to the drain driver peripheral circuit. Flows. As described above, by using the COG method and the multilayer flexible substrate, the restriction on the outer width of the information processing device can be eliminated, and a small-sized information processing device with low power consumption can be provided.

<< Planar and Cross-sectional Structure Near the Driver IC Chip Mounting Portion >> FIG. 25 shows the lower substrate S of the liquid crystal display element PNL.
FIG. 3 is an enlarged view of a main part showing a state where a driving IC is mounted on UB1. FIG. 26 shows the vicinity of the mounting portion of the drain driving IC of the lower substrate SUB1 of the liquid crystal display element and the cutting line CT of the substrate.
1 is a plan view of a main portion near FIG.
It is sectional drawing along the -B 'line and CC' line. In FIG. 25, the upper substrate SUB2 is indicated by a dashed line, but is positioned above the lower substrate SUB1 so as to overlap with the seal pattern S.
L encloses the liquid crystal LC including the effective display area AR.

The electrode COM on the substrate SUB1 is a wiring to be electrically connected to the common electrode pattern on the substrate SUB2 via conductive beads or silver paste. Wiring DTM
(Or GTM) is to supply an output signal from the driving IC to a wiring in the effective display unit AR. The input wiring Td supplies an input signal to the driving IC.
The anisotropic conductive film ACF includes a plurality of driving I
An elongated ACF2 common to the portion C and an elongated ACF1 common to the input wiring pattern portions to the plurality of driving ICs are separately attached.

A passivation film (protective film) PSV1,
Although PSV2 is also shown in FIG. 30, the wiring portion is covered as much as possible to prevent electrolytic corrosion, and the exposed portion is anisotropic conductive film ACF1.
To cover.

Further, the periphery of the side surface of the driving IC is filled with an epoxy resin or a silicone resin SIL (see FIG. 30), and protection is multiplexed.

In FIG. 39, the gate-on level waveform (DC) and the gate-off level waveform are -9 V to -14
V, and turns on at 10V. The drain waveform (during black display) and the common voltage V _com waveform are approximately 0V to 3V.
The level changes between V. For example, in order to change the drain waveform of the black level every horizontal period (1H), the logic processing circuit performs logical inversion on a bit-by-bit basis and inputs the result to the drain driver. The gate off-level waveform operates with substantially the same amplitude and transfer as the common voltage V _com .

FIG. 38 is an explanatory diagram of the flow of display data and clock signals to the gate driver 104 and the drain driver 103. As described above, the display control device 10
1 is a control signal (clock signal,
In response to the display timing signal and the synchronization signal, the clock D1 (CL
1), a shift clock D2 (CL2) and display data are generated, and at the same time, as a control signal to the gate driver 104, a frame start instruction signal FLM and a clock G (CL
3) and generate display data.

The carry output at the preceding stage of the drain driver 103 is directly used as the drain driver 103 at the next stage.
Is given to the carry input.

As described above, the present invention has been specifically described based on the embodiments. However, the present invention is not limited to the above-described embodiments, and various changes can be made without departing from the gist of the present invention. Needless to say. For example, in the above embodiment, the present invention is applied to an active matrix type liquid crystal display device.
The present invention can be similarly applied to other types of liquid crystal display devices. The present invention is not limited to the flip-chip type in which the driving IC is directly mounted on a substrate, but can be similarly applied to a conventional device using TCP.

[0171]

As described above, according to the present invention,
Since the connection portion between the interface substrate and the flexible substrate on the drain side is substantially flush with the flexible substrate, the overlapping of the flexible substrate FPC2 on the drain side as described in the related art is eliminated, and the thickness of the entire liquid crystal display device is reduced. And the thickness can be reduced.

[Brief description of the drawings]

FIG. 1 is a plan view of a principal part schematically illustrating a configuration of a drain-side flexible substrate for describing one embodiment of a liquid crystal display device according to the present invention.

FIG. 2 is a cross-sectional view of a principal part schematically illustrating a state where the drain-side flexible substrate shown in FIG. 1 is connected to an interface substrate.

FIG. 3 is an exploded perspective view showing a state before a liquid crystal display element is covered by an upper case constituting a housing of the liquid crystal display device.

FIG. 4 is a development showing a state before an illumination light source (backlight) and various optical films stacked on the upper case and the lower surface of the liquid crystal display element shown in FIG. 3 are housed in the lower case and fixed to the upper case. It is a perspective view.

FIG. 5 is an assembled view of the liquid crystal display device (liquid crystal display module), which is a front view and side views of the liquid crystal display element PNL viewed from the front side (that is, the liquid crystal display element PNL side).

FIG. 6 is an explanatory diagram of an interface substrate on which the liquid crystal display module of FIG. 5 is mounted on a back surface and side surfaces thereof.

FIG. 7 is a plan view of an essential part for explaining an arrangement of a gate-side flexible substrate FPC1 and a drain-side flexible substrate FPC2.

FIG. 8 is an exploded perspective view illustrating the overall configuration of another example of the liquid crystal display device according to the present invention.

FIG. 9 is an assembled view of the liquid crystal display module, which is a front view, a front side view, a right side view, and a left side view as viewed from the front side of the liquid crystal display element.

FIG. 10 is an assembled view of the liquid crystal display module,
FIG. 3 is a rear view of the liquid crystal display element as viewed from the rear side.

FIG. 11 is a front view of a liquid crystal display device with a driving circuit board in which a gate-side flexible substrate and a drain-side flexible substrate before being bent are mounted on an outer peripheral portion of the liquid crystal display device.

FIG. 12 is a rear view of the liquid crystal display device with a drive circuit board of FIG. 6 on which an interface circuit board is mounted.

FIG. 13 is a rear view showing a state in which a flexible board and an interface circuit board are mounted under a shield case SHD, and then the flexible board is bent to accommodate a liquid crystal display element in the shield case.

FIG. 14 is an explanatory diagram of a front side and a front side of a backlight.

15 is an explanatory view of a front surface and a front side surface of the backlight of FIG. 14 from which a prism sheet and a diffusion sheet are removed.

FIG. 16 is an explanatory view of the front and front sides similar to FIG. 15, showing another example of the configuration of the backlight.

FIG. 17 is an explanatory diagram of a lower case (mold case).

FIG. 18 is an enlarged explanatory view of a corner portion of the mold case in FIG.

FIG. 19 is an explanatory diagram of attachment of a light source reflector in a storage section of the light guide GLB in a molded case MCA.

FIG. 20 is an explanatory diagram of an installation state of a reflection plate of a linear light source.

FIG. 21 is an explanatory diagram of a multilayer flexible substrate FPC2 that drives a drain driver.

FIG. 22 is an explanatory diagram of a mounting portion of the multilayer flexible substrate PC2.

FIG. 23 is an explanatory diagram of a multilayer flexible substrate for driving a gate driver.

FIG. 24 is a wiring diagram showing a connection relationship between signal wiring in a multilayer flexible substrate and input signals to a driving IC on a lower substrate.

FIG. 25 is an explanatory diagram of a state where a driving IC is mounted on a lower substrate of a liquid crystal display element.

FIG. 26 shows a drain driving I on the lower substrate of the liquid crystal display element.
FIG. 4 is a plan view of a main part around a mounting portion of C and near a cutting line CT1 of the substrate.

FIG. 27 is a sectional view taken along lines AA ′, BB ′, and CC ′ in FIG. 21;

FIG. 28 is a perspective view illustrating a method of bending and mounting a multilayer flexible substrate and a connection portion with another multilayer flexible substrate.

29 is a partially enlarged view of the surface conductor layer of the multilayer flexible board FPC and the interface circuit board shown in FIG. 31.

FIG. 30 is a sectional view taken along line A-A ′ of FIG. 25.

FIG. 31 is an explanatory diagram of an interface circuit board PCB.

FIG. 32 is a sectional view taken along line A-A ′ of FIG. 5;

FIG. 33 is a sectional view taken along line B-B ′ of FIG. 5;

FIG. 34 is a sectional view taken along line C-C 'of FIG.

FIG. 35 is a sectional view taken along line D-D 'of FIG.

FIG. 36 is a block diagram illustrating a circuit configuration of a liquid crystal display element PNL and a driving circuit and the like arranged on an outer peripheral portion thereof.

FIG. 37 is a block diagram showing an equivalent circuit of the liquid crystal display module.

FIG. 38 is an explanatory diagram of display data and a flow of a clock signal for a gate driver and a drain driver.

FIG. 39 is a diagram showing levels of common voltage, drain voltage, and gate voltage and waveforms thereof.

FIG. 40 is a block diagram showing a schematic configuration of each driver (drain driver, gate driver, common driver) of the liquid crystal display element and a signal flow.

FIG. 41 is a timing chart showing display data input from the main computer (host) to the display control device and signals output from the display control device to the drain driver and the gate driver.

FIG. 42 is a perspective view of a notebook computer or a word processor on which a liquid crystal display module is mounted.

FIG. 43 is a perspective view of another notebook personal computer or word processor on which a liquid crystal display module is mounted.

FIG. 44 is a plan view of a principal part schematically illustrating the configuration of a drain-side flexible substrate constituting a conventional liquid crystal display device.

45 is a fragmentary cross-sectional view schematically explaining a state where the drain-side flexible substrate shown in FIG. 44 is connected to an interface substrate.

[Explanation of symbols]

 FPC2 Drain-side flexible substrate FSL Wiring part to drive IC JT2 Convex part CT4 Connection terminal SUB1 Lower substrate forming liquid crystal display element SUB2 Upper substrate forming liquid crystal display element POL1, POL2 Polarizing plate IC driving IC CHD chip part BNTL folding line.

 ──────────────────────────────────────────────────の Continuing on the front page (72) Inventor Kaoru Hasegawa 3300 Hayano Mobara-shi, Chiba Pref.Electronic Device Business Division, Hitachi, Ltd. (72) Inventor Katsuhiko Yarida 3300 Hayano Mobara-shi, Chiba Pref. Inside

Claims (1)

[Claims] 1. A liquid crystal display element having a liquid crystal layer sealed between two substrates, and a driving IC mounted on a long side and a short side adjacent to the long side, and disposed on a back surface of the short side. To the drive circuit mounted on the long side, connecting one side edge in the longitudinal direction, bending the other side edge to the back surface of the liquid crystal display element, and connecting to the connector provided on the interface circuit board. A flexible circuit board for connecting various signals for display from the interface circuit board to a drive IC, the connection circuit being provided from a lower surface of the interface circuit board, and illuminating the lower surface of the liquid crystal display element An upper case in which a light source is arranged and a window is formed in an effective display area of the liquid crystal display element, and a lower case in which a concave portion for holding the illumination light source is formed is integrated. In the liquid crystal display device, the flexible circuit board has a protrusion formed on the other side edge in a substantially perpendicular direction and provided with the connection terminal on the surface, and the protrusion is provided on the flexible circuit board. The connection terminal is folded upside down such that the connection terminal is connected to the connector of the interface circuit board in a state where the connection terminal is bent on the back surface of the liquid crystal display element, and the connection terminal portion does not overlap with the flexible circuit board. Liquid crystal display device.