JP2000089223A - Liquid crystal display - Google Patents

Abstract

(57) [Summary] [PROBLEMS] To reduce the thickness of a backlight device to reduce the thickness of an entire liquid crystal display device, and to facilitate the assembling work of the backlight device. A mold for housing a backlight device, comprising: a liquid crystal display element enclosing a liquid crystal layer in which a gap between a first substrate and a second substrate is superimposed; and a backlight device installed on the back surface of the liquid crystal display device. A liquid crystal display element is fixed between the case and the upper frame, and the backlight device is arranged along a light incident surface which is at least one side edge of the light guide plate GLB made of a transparent material; The light source reflector LS for causing the emitted light to be effectively incident on the light guide plate GLB, the light diffusion plate SPS laminated on the liquid crystal display element side of the light guide plate GLB, and the liquid crystal display element of the light guide plate GLB are opposite to each other. A reflector RFS installed so as to cover the entire surface of the linear light source LP. The reflector RFS is extended to the lower surface of the linear light source LP to form a reflector extension RFS-E. The light guide plate G and E with respect to the linear light source LP
The LB was bent to the opposite side to the light incident surface, and a separate reflecting sheet LS was provided on the upper surface of the linear light source to form a light source reflector.

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 gap liquid crystal layer is formed by overlapping a first substrate and a second substrate made of a transparent material. The present invention relates to a liquid crystal display device comprising a backlight device installed on the back of an element.

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

A liquid crystal panel constituting the former TN mode active matrix type liquid crystal display device comprises a pair (a first substrate (lower substrate) and a second substrate (upper substrate)) made of a transparent material such as a glass plate. The liquid crystal is twisted by 90 ° in the two substrates, and the absorption axis directions are arranged in crossed Nicols on the outer surfaces of the upper and lower substrates of the liquid crystal panel, and the absorption axes on the incident side are parallel or orthogonal to the rubbing direction. And two polarizing plates.

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 the IPS mode liquid crystal display device is initially 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 slightly parallel to the electrode wiring direction when no voltage is applied. When the voltage is applied, the direction of the director of the liquid crystal layer shifts in the direction perpendicular to the electrode wiring direction with the application of the voltage, and the director direction of the liquid crystal layer changes to the director direction when no voltage is applied. When tilted in the direction of the electrode wiring by 45 °, the liquid crystal layer at the time of applying the voltage changes the azimuthal angle of the polarized light by 90 ° like a half-wave plate.
By rotating the polarizer, the transmission axis of the exit-side polarizing plate and the azimuth of the polarized light coincide with each other, 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, a liquid crystal display element (hereinafter, also referred to as a liquid crystal panel) constituting a TN type active matrix type liquid crystal display device (hereinafter simply referred to as an active matrix type liquid crystal display device for simplicity) has a liquid crystal. A gate line group extending in the x-direction and juxtaposed in the y-direction on a surface of one of two transparent insulating substrates made of glass or the like opposed to each other with a layer interposed therebetween, 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 area surrounded by the group of gate lines and the group of drain lines becomes a pixel area. In this pixel area, for example, a thin film transistor (TFT) and a transparent pixel electrode are formed as active elements (switching elements). I have.

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.

It is to be noted that, 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
Chip (semiconductor integrated circuit, hereinafter simply referred to as drive IC or I
C) 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 drive IC is mounted is externally mounted, an intersecting region of a group of gate lines and a group of drain lines of the substrate is provided. The area occupied by the area (usually called a frame) between the outline of the display area and the outer frame of the substrate 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 demand for reducing the outer dimensions of the 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. IC for scanning and IC for scanning drive
Is directly mounted on one substrate (lower substrate), a so-called flip-chip system or chip-on-glass (COG) system 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.

Each of the above-mentioned liquid crystal display devices has an illumination light source (backlight) for visualizing an image formed on the liquid crystal panel on the back surface of the liquid crystal panel. The illumination light source includes a side edge type backlight having a linear light source such as a cold cathode fluorescent tube on at least one side edge (light incident surface) of a light guide plate formed of an acrylic resin plate or the like, and a light guide plate on the back surface of the liquid crystal panel. There is a direct backlight in which a linear light source or the like is arranged. Note that a front light type in which illumination light is emitted from the observation surface side of the liquid crystal panel is also known.

[0021]

In particular, a side edge type backlight is used for a portable personal computer or the like in which weight and thickness are important. This side edge type backlight (hereinafter, simply referred to as a backlight) is composed of a light guide plate and a linear light source as described above, and a reflection plate is provided on the back surface of the light guide plate, and a linear light source is provided for the linear light source. A light source reflector is provided for effectively causing the light emitted from the linear light source to enter the light incident surface of the light guide plate.

On the upper surface of the light guide plate, that is, on the liquid crystal panel side, a diffusion plate for uniforming the luminance distribution of the illumination light from the backlight and a prism sheet for directing the illumination light toward the liquid crystal panel are laminated. ing.

In a conventional light source reflector, both edges of a U-shaped reflector surrounding a linear light source are adhered and fixed to a light guide plate with a double-sided tape.

FIG. 25 is a perspective view illustrating a schematic structure of a conventional liquid crystal display device, and FIG. 26 is a cross-sectional view illustrating a detailed structure of a main part taken along line XX of FIG. In FIG. 26, the liquid crystal panel is not shown. The backlight BL installed on the back of the liquid crystal panel PNL shown in FIG.
As shown in the detailed structure of FIG. 26, a light diffusion plate (also simply referred to as a diffusion plate) and two prism sheets PRS are laminated on the upper surface (the liquid crystal panel side) of the light guide plate GLB having a wedge-shaped cross section. Adhesively fix the edge with double-sided adhesive tape BAT,
A linear light source LP is disposed on one side edge of the light guide plate GLB, which is a light incident surface, and a U-shaped light source reflector LS is connected to the linear light source LP.
Are placed so as to surround each side and the edges are double-sided adhesive tape BAT
It is fixed with adhesive. In addition, a reflection plate RFS is disposed on the lower surface of the light guide plate GLB, and its edge is double-sided adhesive tape BA.
It is adhesively fixed with T.

[0025]

In the above prior art, the diffusion plate SPS or the prism sheet P laminated on the light guide plate GLB is used.
RS, the reflector RFS, and the light source reflector LS are bonded and fixed with a double-sided reflective tape BAT, respectively, and these are the thickest portions in the structure of the backlight device, that is, the lines that are the light entrance surfaces of the wedge-shaped light guide plate GLB. Are concentrated at the end on the side of the light source LP.

For this reason, the large number of double-sided tapes described above increase the maximum thickness of the backlight device, and as a result, are one of the factors limiting the thinning of the liquid crystal display device.
In addition, when assembling the backlight device, the light source reflector LS is wound around the linear light source LP, and its edge is adhered with a double-sided tape, which hinders improvement in workability.

An object of the present invention is to solve the above-mentioned problems of the prior art, reduce the thickness of the backlight device, reduce the thickness of the liquid crystal display device as a whole, and facilitate the assembling work of the backlight device. It is to provide a liquid crystal display device having a structure.

[0028]

In order to achieve the above object, the present invention reduces the double-sided tape for fixing the light source reflector by extending the reflector to cover the bottom and back or top surface of the linear light source. The light diffusion plate, the prism sheet, the reflection plate and the mold case are positioned at predetermined positions by the engagement of the irregularities formed on each side, thereby eliminating the need for the respective double-sided adhesive tapes for fixing.

That is, the present invention is characterized by having the following constitutions (1) to (4).

(1) A liquid crystal display element enclosing a liquid crystal layer in which a gap between a first substrate and a second substrate overlaps, and a backlight device installed on the back of the liquid crystal display device, wherein the backlight device A linear light source in which the backlight device of a liquid crystal display device in which a liquid crystal display element is fixed by a molded case and an upper frame that accommodates the light source is disposed along a light incident surface that is at least one side edge of a light guide plate made of a transparent material. And a light source reflector for causing the light emitted from the linear light source to efficiently enter the light guide plate, a light diffusion plate laminated on the liquid crystal display element side of the light guide plate, and the liquid crystal display element of the light guide plate. A reflector installed so as to cover the entire surface on the opposite side, extending the reflector to the lower surface of the linear light source, and bending the light source with respect to the linear light source to the side opposite to the light incident surface of the light guide plate. , And line The upper surface of the light source by installing reflecting sheet separately, characterized in that the light source reflector.

According to this configuration, the main part of the light source reflector can be constituted by the extended reflector, and the assembling work can be simplified.

(2) A liquid crystal display element enclosing a liquid crystal layer in which a first substrate and a second substrate overlap each other, and a backlight device installed on the back of the liquid crystal display device, wherein the backlight device A linear light source in which the backlight device of the liquid crystal display device in which the liquid crystal display element is fixed by the mold case and the upper frame that accommodates the liquid crystal display device is arranged along at least one side edge of the light guide plate made of a transparent material. And a light source reflector for causing the light emitted from the linear light source to efficiently enter the light guide plate, a light diffusion plate laminated on the liquid crystal display element side of the light guide plate, and the liquid crystal display element of the light guide plate. A reflector provided so as to cover the entire surface on the opposite side, wherein the reflector is extended to the lower surface of the linear light source, and the light incident surface of the light guide plate with respect to the linear light source is an upper surface from the opposite side. Like covering Bent to is characterized in that the light source reflector.

According to this configuration, the entire light source reflector can be integrally formed by the extended reflector, and the assembling work can be simplified.

(3) A liquid crystal display element enclosing a liquid crystal layer in which a first substrate and a second substrate overlap each other, and a backlight device installed on the back of the liquid crystal display device, A linear light source in which the backlight device of a liquid crystal display device in which a liquid crystal display element is fixed by a molded case and an upper frame that accommodates the light source is disposed along a light incident surface that is at least one side edge of a light guide plate made of a transparent material. And a light source reflector for causing the light emitted from the linear light source to efficiently enter the light guide plate, a light diffusion plate laminated on the liquid crystal display element side of the light guide plate, and the liquid crystal display element of the light guide plate. A reflector provided so as to cover the entire surface on the opposite side, and the reflector is extended to the lower surface of the linear light source, and the linear light source is bent opposite to the light incident surface of the light guide plate. And the light The diffusion plate extend to the upper surface of the linear light source is characterized in that the light source reflector.

With this configuration, the light source reflector can be constituted by the extended reflector and the light diffuser, and the assembly work can be simplified.

(4) In the above (1) to (3), the light diffusion plate, the prism sheet and the reflection plate are provided with a projection at a part of the edge other than the light incident surface side, and the mold case is provided with a projection. A concave portion is provided at a position corresponding to the convex portion, and the convex portion is engaged with the concave portion to secure a predetermined installation position.

With this configuration, a double-sided adhesive tape for fixing the light diffusion plate, the prism sheet, and the reflection plate to be laminated on the light guide plate becomes unnecessary, and the thickness of the entire liquid crystal display device can be reduced by making the backlight device thinner. Can be.

It should be noted that the present invention is not limited to the above-described configurations, and various changes can be made without departing from the technical idea of the present invention.

[0039]

Embodiments of the present invention will be described below in detail with reference to the accompanying drawings.

FIG. 1 is a sectional view of an essential part of a backlight device for explaining a first embodiment of the liquid crystal display device according to the present invention, and corresponds to FIG. The backlight device of the present embodiment includes:
A light diffusion plate SPS and two prism sheets PRS are stacked on the upper surface of the light guide plate GLB, and a reflection plate RFS is provided on the lower surface.

A linear light source LP (generally, a cold cathode fluorescent tube) is provided along a side edge which is a light incident surface of the light guide plate GLB. As a light source reflector for effectively causing the light emitted from the linear light source LP to enter the light incident surface, a reflector RFS installed on the lower surface of the light guide plate GLB is extended to the lower surface of the linear light source LP, and this reflector is provided. The extension part RFS-E is bent at the back of the linear light source LP.

On the upper surface of the linear light source LP, there is provided a reflection sheet LS.
And the edge is fixed to the edge of the prism sheet PRS with a double-sided adhesive tape BAT.

FIG. 2 is a perspective view of a main part of a backlight device for explaining a first embodiment of the liquid crystal display device of the present invention. The backlight device is a molded case MCA made of resin
However, a concave portion RET is formed inside the side of the molded case MCA adjacent to the end where the linear light source LP is installed (and also inside the side opposite to the end where the linear light source LP is installed if necessary). Have been.

On the other hand, the edges of the reflection plate RFS, the light diffusion plate SPS, and the prism sheet PRS are attached to the mold case MCA.
Is formed with a convex portion PJ that engages with the concave portion RET. This convex part PJ is connected to the concave part RE of the mold case MCA.
By engaging with T, the reflection plate RFS, the light diffusion plate SPS, and the prism sheet PRS can be fixed without using a double-sided adhesive tape as in the above-described conventional example. The thickness of the backlight device can be reduced.

According to this embodiment, the overall thickness of the liquid crystal display device can be reduced, and the cost can be reduced by simplifying the assembly work and reducing the number of parts.

FIG. 3 is a sectional view of a principal part of a backlight device for explaining a second embodiment of the liquid crystal display device of the present invention, and is a sectional view similar to FIG. The backlight device of this embodiment also has a light diffusing plate SPS and two prism sheets PRS laminated on the upper surface of the light guide plate GLB, and a reflector RFS on the lower surface.
Is installed.

A linear light source LP is provided along the light incident surface of the light guide plate GLB. As a light source reflector for effectively causing the light emitted from the linear light source LP to enter the light incident surface, a reflector RFS installed on the lower surface of the light guide plate GLB is extended to the lower surface of the linear light source LP, and this reflector is provided. Extension R
The reflector FS-E is bent from the back to the upper surface of the linear light source LP to surround the linear light source LP from three sides.

In this embodiment, the reflector extension RFS-E
Since the upper side edge of the linear light source LP is not fixed to the prism sheet PRS, there is no double-sided adhesive tape.
In some cases, it can be fixed to the prism sheet PRS using a double-sided adhesive tape.

The fixing of the reflection plate RFS, the light diffusion plate SPS, and the prism sheet PRS to the mold case MCA is performed in the same configuration as that of FIG.

According to this embodiment, the entire thickness of the liquid crystal display device can be reduced, and the cost can be reduced by simplifying the assembling work and further reducing the number of parts.

FIG. 4 is a sectional view of a principal part of a backlight device for explaining a liquid crystal display device according to a third embodiment of the present invention. FIG. 4 is a sectional view similar to FIG. It is shown. The backlight device of the present embodiment also
A light diffusion plate SPS and two prism sheets PRS are stacked on the upper surface of the light guide plate GLB, and a reflection plate RFS is provided on the lower surface.

[0052] A linear light source LP is provided along the light incident surface of the light guide plate GLB. As a light source reflector for effectively causing the light emitted from the linear light source LP to enter the light incident surface, a reflector RFS installed on the lower surface of the light guide plate GLB is extended to the lower surface of the linear light source LP, and this reflector is provided. Extension R
FS-E is bent at the back of the linear light source LP. A reflection sheet LS is arranged on the upper surface of the linear light source LP, and both end edges of the reflection sheet LS are fixed to the end edge of the prism sheet PRS and the mold case MCA with a double-sided adhesive tape BAT.

In this embodiment, the reflection sheet LS is fixed to the edge of the prism sheet PRS and the mold case MCA. However, the use location of the double-sided tape BAT may be only one of them.

The fixing of the reflection plate RFS, the light diffusion plate SPS, and the prism sheet PRS to the mold case MCA is performed in the same configuration as that of FIG.

According to this embodiment as well, the overall thickness of the liquid crystal display device can be reduced, and the cost can be reduced by simplifying the assembling work and further reducing the number of parts.

FIG. 5 is a sectional view of a principal part of a backlight device for explaining a fourth embodiment of the liquid crystal display device of the present invention, and is a sectional view similar to FIG. The backlight device of this embodiment also has a light diffusing plate SPS and two prism sheets PRS laminated on the upper surface of the light guide plate GLB, and a reflector RFS on the lower surface.
Is installed.

A linear light source LP is provided along the light incident surface of the light guide plate GLB. As a light source reflector for effectively causing the light emitted from the linear light source LP to enter the light incident surface, a reflector RFS installed on the lower surface of the light guide plate GLB is extended to the lower surface of the linear light source LP, and this reflector is provided. Extension R
FS-E is bent at the back of the linear light source LP. On the upper surface of the linear light source LP, a light diffusion plate extension SPS-E obtained by extending the light diffusion plate SPS is arranged.

In this embodiment, the reflector extension RFS-E
Although the light diffusion plate extension SPS-E is free, one or both of them may be bonded to the mold case MCA (see FIG. 4) via a double-sided adhesive tape.

The fixing of the reflection plate RFS, the light diffusion plate SPS, and the prism sheet PRS to the mold case MCA is performed in the same configuration as that of FIG.

According to this embodiment as well, the overall thickness of the liquid crystal display device can be reduced, and the cost can be reduced by simplifying the assembling work and further reducing the number of parts.

Next, a specific example of the liquid crystal display device to which the present invention 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. 6 and 7 are exploded perspective views for explaining an entire configuration example of the liquid crystal display device according to the present invention. FIG. 6 shows a state before the liquid crystal panel is covered by an upper case constituting a housing of the liquid crystal display device. FIG. 7 is an exploded perspective view showing the state shown in FIG. 7. FIG. 7 shows a case in which the backlight and various optical films (light diffusion plate, prism sheet, etc.) installed on the lower surface of the upper frame and the liquid crystal panel shown in FIG. FIG. 4 is an exploded perspective view showing a state before being fixed to a case.

In FIGS. 6 and 7, SHD is an upper frame (also referred to as an upper case), PNL is a liquid crystal panel (liquid crystal display element), and SPCs (SPC1 to SPC).
2) is an insulating spacer, SCP-P is a protrusion of the spacer SPC (fitted into an opening opened in the upper frame SHD),
BAT is a double-sided adhesive tape, FPC1 and FPC2 are multilayer flexible substrates (FPC1 is a gate-side substrate, FPC2 is a drain-side substrate), PCB is an interface substrate, S
PS is a light diffusion plate, PRS is a prism sheet, GLB is a light guide plate, RFS is a reflection plate, G is a rubber cushion, MCA is a mold case (also referred to as a lower case), LP is a linear light source (cold cathode fluorescent lamp: CFL). , LS is a light source reflector, LPC
H is a cable holder for a cold cathode fluorescent tube.

The upper frame SHD shown in FIG.
Is manufactured by stamping and bending a single metal plate by a press working technique. WD is an opening (window) that exposes the liquid crystal panel PNL to the field of view. In the liquid crystal panel PNL, a liquid crystal layer is sandwiched between two substrates, and a plurality of gate lines and drain lines crossed and a thin film transistor is disposed at an intersection of the gate line and the drain line on the lower substrate. One pixel is constituted by the pixel electrode driven by.

The driving IC for driving the gate is a liquid crystal panel PN.
It is mounted on the lower board edge of the L interface board PCB side, and supplies a drive signal to a gate drive IC by the flexible board FCP1. A drive IC for driving the drain is mounted on the lower substrate adjacent to the side on which the interface substrate is installed, and the flexible substrate FCP2
As a result, a drive signal is supplied to the drain drive IC.

Each of the above-described drive ICs and the flexible substrate F
A liquid crystal panel on which CP1 and FCP2 and an interface board PCB are mounted is mounted on a peripheral circuit mounted liquid crystal display element ASB.
Called.

A light guide plate GLB is provided on the inner periphery of the mold case MCA via a rubber cushion GC. A reflection plate RFS is provided on the back surface of the light guide plate GLB. A diffusion plate SPS and two prism sheets PRS are stacked on the upper surface of the light guide plate GLB, and the peripheral circuit mounting liquid crystal display element ASB shown in FIG.
And fixed claw NL formed on the periphery of upper frame SHD
The liquid crystal display device (also referred to as a liquid crystal display module) is assembled by fitting and fixing the fixing recesses formed in the mold case MCA.

A convex portion PJ is formed on predetermined sides of the reflection plate RFS, the diffusion plate SPS, and the prism sheet PRS (here, three sides other than the installation side of the linear light source LP). In the mold case MCA, a concave portion RET is formed at a position corresponding to the convex portion PJ. These convex parts PJ
And the concave portion RET are engaged with each other, whereby the reflection plate RFS,
The diffusion plate SPS and the prism sheet PRS are fixed to the mold case MCA.

The numbers and positions of the convex portions PJ and concave portions RET are not limited to those shown in the figure, but may be arbitrarily selected according to the type and size of the liquid crystal display device.

Next, a configuration example of the liquid crystal display device according to the present invention will be described in more detail with reference to FIG.

FIG. 8 is an assembled view of the liquid crystal display device, which is a front view and a side view as viewed from the liquid crystal panel PNL side. FIG. 9 is an explanatory diagram of a back surface and an interface substrate on which the liquid crystal display device of FIG. 8 is mounted.

The liquid crystal display device has two housing / holding members, a mold frame MCA and an upper frame SHD. H
LD is four mounting holes provided for mounting the liquid crystal display device MDL as a display unit on an information processing device such as a personal computer or a word processor. ALV is a groove for fixing the internal structure.

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

FIG. 9B shows an interface substrate PC.
FIG. 10 is a detailed explanatory view of an interface circuit board having a controller section and a power supply section. FIG. 10A is a back view (bottom view), and FIG. 10B is a portion of the mounted hybrid integrated circuit HI. The front lateral side view, (c) shows a front (top) view.

As shown in FIG. 10A, a connector CT for receiving signals from the main computer and necessary power supply is provided on one surface of the interface board PCB.
1. A low-voltage differential receiving circuit chip LVDS for converting a serial low-voltage differential signal received from a main body computer into an original parallel signal, a control circuit chip TCON, and digital / digital for generating various DC voltages Conversion circuit chip DD, and gate-side flexible substrate FPC1 and drain-side flexible substrate FP to be described later
Connectors CT3 and CT2 for connection to C2 are mounted. CJH is a notch for alignment.

The digital / digital conversion circuit chip DD is a hybrid circuit, and is configured as shown in FIG. FIG. 10A is a side view of the digital / digital conversion circuit chip DD. (B) is a sectional view thereof. FIG. 10C shows the interface substrate P
The conductive film ERH for connecting a ground terminal (GND) formed on the entire surface of the CB to ground is shown.

As the interface circuit board PCB (also simply referred to as the board PCB), a multilayer printed board made of a glass epoxy material was used. 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 rear 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 of the flexible board FPC1 as the gate driver board and the interface circuit board PCB via the electrical connection means JN1 uses the connector CT3 in this configuration.

FIG. 11 is a plan view of an essential part for explaining the arrangement of the gate-side flexible substrate and the drain-side flexible substrate. A drive circuit element IC for gate drive is mounted on the upper surface of the liquid crystal panel PNL on the interface substrate side, and a gate-side flexible board FPC1 connected to the drive circuit element IC is arranged. Flexible board FP
A drive circuit element IC for driving the drain is mounted on the lower side of the liquid crystal panel PNL adjacent to C1, and a flexible substrate FPC2 connected to the drive circuit element IC is arranged.

A protrusion JN4 is formed at the end of the flexible board FPC2 on the gate side flexible board FPC1 side, and a connector (flat connector) for connecting to the connector CT2 of the interface board PCB at this 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.

With this configuration, the interface board P
The connection portion between the CB and the flexible substrate FPC2 on the drain side is substantially flush with the flexible substrate FPC2. Therefore, the overlapping of the flexible substrate FPC2 on the drain side is eliminated, and the thickness of the entire liquid crystal display device is reduced,
Thinning can be promoted.

FIG. 12 is a cross-sectional view taken along the line AA ′ of FIG. 8, FIG. 13 is a cross-sectional view taken along the line BB ′, FIG. 14 is a cross-sectional view taken along the line CC ′, and FIG. FIG. 4 shows a cross-sectional view taken along line D ′.

The liquid crystal display device shown in FIG.
This is a configuration when the backlight device described in (1) is used, and the substrates SUB1 and SUB constituting the liquid crystal panel PNL
When viewed from the vertical direction, the interface circuit board PCB is disposed below the lower surface of the SUB1 so as to overlap the liquid crystal panel PNL (see FIG. 13). The flexible substrate FPC1 for the gate driver has one end electrically and mechanically connected directly to the substrate SUB1 of the liquid crystal panel PNL. Unlike the drain side, the flexible substrate FPC1 does not bend and has almost the entire width of the interface circuit substrate PC.
B is superimposed on B.

As described above, the interface circuit board P
By partially overlapping the CB with the substrate SUB1 of the liquid crystal panel PNL and further arranging the circuit board FPC1 for the gate driver on the interface circuit board PCB, the width and area of the frame portion can be reduced, and the liquid crystal panel and The external dimensions of an information processing device such as a personal computer or a word processor incorporating the liquid crystal panel as a display unit can be reduced. Then, the reflection plate RF constituting the backlight device
S. To reduce the overall thickness of the information processing apparatus by completely eliminating or minimizing the use of double-sided adhesive tape for fixing optical elements such as the light diffusion plate SPS and the prism sheet PRS. Can be.

The liquid crystal panel PNL and the upper frame SHD are
A spacer SPC made of resin or the like is provided between the lower substrate SUB1 and the liquid crystal panel PNL.
It is fixed with an AT interposed.

As shown in FIGS. 13 and 14, the upper frame SHD is provided with a plurality of openings HOLS in the longitudinal direction thereof.
The displacement of the spacer SPC is prevented by fitting PC2-P.

As shown in FIG. 14, a flexible substrate FPC2 for a drain driver is bent and bonded to the side opposite to the pattern forming surface of the substrate SUB1. Polarizing plates POL1 and POL2 are located slightly (about 1 mm) outside of the effective display area AR, and FPC2 is separated from it by about 1 to 2 mm.
The end of is located.

The distance from the edge of the substrate SUB1 to the tip 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.

[0092] At least one surface of the rubber cushion GC is provided with an adhesive material or a double-sided adhesive tape, and the other is fixed while being attached to one of the light guide plate GLB and the mold case MCA. The rubber cushion does not need to be inserted at all of the illustrated positions, and may be used only for a portion to be protected against impact or the like.

FIG. 16 is a plan view of an essential part for explaining a detailed structure near one pixel area of the liquid crystal panel. 17 is a sectional view taken along the line IV-IV of FIG. 16, FIG. 18 is a sectional view taken along the line VV, and FIG. 19 is a sectional view taken along the line VI-VI of FIG. FIG. 16A shows a planar structure of a pixel on the input terminal side, and FIG. 16B shows a part of a planar structure of a pixel farther from the input terminal (for example, a terminal side).

As shown in FIG. 17, the liquid crystal panel is a first transparent substrate, that is, a lower substrate SU based on the liquid crystal layer LC.
On the B1 side, a thin film transistor TFT and a pixel electrode IT
O1 is formed, and a color filter F is provided on the substrate SUB2 side.
IL and a first black matrix BM1 are formed. In FIG. 17, POL1 is a lower substrate SU.
The polarizing plate provided on the B1 side, POL2 is the upper substrate SU.
It is a polarizing plate provided on the B2 side.

On the inner surface of the substrate SUB1 on the liquid crystal layer side, x
Gate signal lines GL extending in the direction and juxtaposed in the y direction are formed. The gate signal line GL is formed of a conductive layer g1 of chromium, molybdenum, an alloy of chromium and molybdenum, aluminum, tantalum, titanium, or the like. Further, in order to reduce the wiring resistance of the gate signal line GL, the gate signal line GL may be formed using a stacked film of the above conductive layers. When aluminum is used for the gate signal line GL, an alloy to which a small amount of metal such as tantalum, titanium, or niobium is added may be used in order to eliminate the formation of projections such as hillocks and whiskers.

A pixel electrode ITO made of a transparent conductive film (for example, Indium-Tin-Oxide) is formed in most of the pixel region surrounded by the gate signal line GL and a drain signal line DL described later. I have. A part of the pixel region on the lower left gate signal line GL in FIG.
This is the area where the FT is formed. Thin film transistor TFT
For example, a gate insulating film GI made of SiN, a semiconductor layer AS made of i-type amorphous Si, a semiconductor layer d0 made of amorphous Si containing impurities, a drain electrode SD2 and a source electrode SD1 are sequentially stacked. I have.

[0097] The drain electrode SD2 and the source electrode SD1 are formed simultaneously with the drain signal line DL. As shown in FIG. 18, the drain signal line DL is formed on the insulating film GI, the semiconductor layer AS, and the semiconductor layer d0 made of amorphous Si containing impurities, and is formed of chromium, molybdenum, or an alloy of chromium and molybdenum. ,
It is formed by a single layer or a stacked layer of a conductive film such as aluminum, tantalum or titanium.

The reason why the semiconductor layer AS and the semiconductor layer d0 containing the impurity are formed in the region where the drain signal line DL is formed is, for example, the level difference between the semiconductor layer AS and the semiconductor layer d0 containing the impurity. This is to prevent disconnection.

The drain electrode S of the thin film transistor TFT
D2 is formed integrally with the drain signal line DL, and the source electrode SD1 is separated from the drain electrode SD2 by a predetermined channel length l (shown by a lowercase letter in L in the figure).

Source electrode SD1 and drain electrode SD
2, a protective film PSV1 made of an insulating film is provided. The protective film PSV1 is a thin film transistor TF of a liquid crystal layer.
It has a function of avoiding characteristic deterioration due to direct contact with T. The protective film PSV1 is a film having good moisture resistance, such as a silicon nitride film or an organic resin film such as polyimide. The pixel electrode ITO1 is formed on the protective film PSV1.

The protective film PSV1 on the source electrode SD1 is provided with a through hole CONT for electrically connecting the source electrode SD1 and the pixel electrode ITO1.

As shown in FIG. 19, the storage capacitance element Cadd has a gate signal line (thin film transistor TFT).
Gate signal line driving the other gate signal line)
GL is used as one electrode, a conductive layer formed simultaneously with the pixel electrode ITO1 is used as the other electrode, and the insulating film GI and the protective film PSV1 interposed therebetween are used as a dielectric film.

The insulating film GI and the protective film PSV1 are formed simultaneously with their formation in the thin film transistor TFT, and the conductive layer as the other electrode is formed simultaneously with the pixel electrode ITO1.

An alignment film ORI1 is formed over the entire surface of the pixel electrode ITO1 to parasitize the alignment of the liquid crystal composition constituting the liquid crystal layer.

In this configuration example, the protective film PSV1 as an insulating film exists between the pixel electrode ITO1 and the gate signal line GL and the drain signal line DL.
Even if O1 and the gate signal line GL or the pixel electrode ITO1 and the drain signal line DL overlap on a plane, no short circuit occurs. Therefore, in this configuration example, the pixel electrode I
Since TO1 can be formed large, the aperture of the pixel becomes large, and the liquid crystal capacitance Cpix increases, so that the storage capacitance Cadd can be reduced.

A first light-shielding film (black matrix) BM1, a color filter FIL, a common transparent electrode COM, and an upper alignment film ORI2 are provided on the inner surface (on the liquid crystal layer LC side) of the upper substrate SUB2 made of glass or the like. They are provided by being sequentially laminated. The first light-shielding film BM1 is formed of a light-shielding metal film such as chromium or aluminum, or a light-shielding organic film obtained by adding a dye, a pigment, carbon, or the like to an organic resin film such as acryl.

The common transparent electrode COM is made of a transparent conductive film such as ITO. The color filter FIL is formed by adding a dye or a pigment to a base made of an organic resin film such as acrylic. In order to prevent the dye or pigment of the color filter FIL from contaminating the liquid crystal layer LC, a color filter protective film made of an organic resin film such as acryl may be provided between the color filter FIL and the common transparent electrode COM.

In this configuration example, FIG.
As shown in FIG. 5, a substrate S on which a drain signal line DL is formed
Second light-shielding film BM2 made of a light-shielding metal film on UB1
Is provided. The second light-shielding film BM2 is made of the same material as the conductive film g1 forming the gate signal line GL.
It is formed in the same layer as L.

The second light-shielding film BM2 has a planar structure.
As shown in FIG. 16A, the pixel electrode ITO is formed so as to overlap with the pixel electrode ITO along the drain signal line DL and not overlap with the drain signal line DL.

On the other hand, in terms of the sectional structure, as shown in FIG. 18, the second light-shielding film BM2 is insulated and separated by the drain signal line DL and the gate insulating film GI. Therefore, the possibility that the second light-shielding film BM2 and the drain signal line DL are short-circuited is low. Further, the pixel electrode ITO1 and the second light shielding film BM
2 is insulated and separated by a gate insulating film GI and a protective film PSV1.

The second light-shielding film BM2 has a function of improving the area of the transmission part of the pixel electrode for one pixel, that is, the aperture ratio, and improving the brightness of the liquid crystal panel. Illumination light from a backlight device installed on the back surface of the substrate SUB1 passes through the substrate SUB1, and is formed of a light-shielding film (a gate signal line GL, a drain signal line DL, and a second light-shielding film BM).
The liquid crystal layer LC enters from a portion where 2) is not formed. This light is applied to the common electrode COM formed on SUB2 and the substrate SU.
It is controlled by the voltage applied between the pixel electrodes ITO1 formed on B1.

In a normally white mode in which the transmittance of light is reduced when a voltage is applied to the pixel electrode ITO1, when the second light-shielding film BM2 is not formed as in the present configuration example, the first light-transmitting film BM2 is provided on the substrate SUB2. It is necessary to widely cover the periphery of the pixel electrode ITO1 with the light-shielding film BM1. Otherwise, light that cannot be controlled by voltage leaks from the gap between the drain signal line DL or the gate signal line GL and the pixel electrode ITO1, and the display contrast decreases. . Further, the substrate SUB2 and the substrate SUB1 are bonded together with the liquid crystal layer LC interposed therebetween, and it is necessary to increase the bonding margin.
The aperture ratio is smaller than in the present configuration in which the second light shielding film BM2 is provided on B1.

In this configuration example, the second light shielding film BM2
Uses the same light-shielding metal film g1 as the gate signal line GL, but may be any as long as it can shield light. The light-shielding film is formed by adding a dye, pigment, carbon, or the like to an organic resin film such as acryl. An insulating light-shielding film may be used.

As shown in FIG. 16, the direction of the channel length 1 of the thin film transistor TFT is arranged perpendicular to the direction in which the gate signal line GL extends. In addition, the pixel electrode ITO
1, a portion 1 overlapping the gate signal line GL for selecting the pixel electrode ITO1 is provided to adjust the gate-source capacitance Cgs to reduce the difference between the pixels in the potential drop component ΔV of the pixel electrode.

Adjustment pattern 1 provided on pixel electrode ITO1
In order to reduce the difference in the potential drop component ΔV of the pixel electrode due to the waveform distortion of the scanning signal in step 4, the overlapping area of the adjustment pattern 14 and the gate signal line GL should be closer to the input terminal as the pixel is farther from the input terminal. It is sufficient to increase the number of pixels by a predetermined amount d.

In this configuration example, the gate-source capacitance Cg
In order to adjust s for each pixel, the gate signal line GL for selecting the pixel electrode ITO1 performs the same function as the first light-shielding film BM1 covering the edge of the pixel electrode. Therefore, the first light-shielding film BM1 covering the overlapping portion l of the pixel electrode ITO1 and the gate signal line GL can be retreated in the direction of the gate signal line GL indicated by the arrow in FIG.
The aperture of the pixel can be enlarged.

In the present configuration example, the storage capacitor Cadd provided in the portion where the pixel electrode ITO1 and the gate signal line GL of the adjacent pixel overlap also has the gate signal line GL of the adjacent pixel made of a light-shielding metal. Therefore, the first light shielding film B
Performs the same function as M1. Therefore, the first light shielding film B
M1 can be retracted to a position where the gate signal line GL is exposed, and the aperture ratio of the pixel is improved.

Further, in this configuration example, the protective film PSV1 and the insulating film GI are used as the dielectric of the gate-source capacitance Cgs. Since it is extremely unlikely that a pinhole exists in the same place of the protective film PSV1 and the insulating film GI, the pixel electrode I is adjusted in the portion 14 for adjusting the gate-source capacitance Cgs.
There is no problem that TO1 and the gate signal line GL are short-circuited.

FIG. 20 is a block diagram showing a liquid crystal panel and circuits arranged on the outer periphery thereof. Although not shown,
In this configuration example, the drain drivers IC _{1 to} IC _M are chip-on-glass made of a drain-side lead line DTM and a gate-side lead line GTM formed on one substrate of the liquid crystal display element and an anisotropic conductive film or an ultraviolet curable resin. It is mounted (COG mounted).

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.

FIG. 21 is a circuit diagram of an equivalent circuit of a liquid crystal panel and a drive circuit and the like arranged on the outer periphery thereof. In this configuration, a thin film transistor (TFT) liquid panel PNL
Drain driver section 1 only below (TFT-LCD)
03 is arranged and X composed of 800 × 600 pixels
The gate driver 1 is located on the side of the GA specification LCD panel.
04, a controller unit 101 and a power supply unit 102 are arranged.

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 panel PNL. This is because the width of the information processing device is limited, and the liquid crystal display device (liquid crystal display module MD
This is because the width of L) also needs to be reduced.

As shown in FIG. 21, 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.

The source electrode of the thin film transistor TFT is connected to the pixel electrode, and the pixel electrode and the common electrode (common electrode)
, A liquid crystal capacitor (C _LC ) is equivalently connected to the source electrode of the thin film transistor TFT. 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 Cadd 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 polarities are inverted during the operation, and therefore, it should be understood that the source electrode and the drain electrode are switched during the operation.

FIG. 22 is an explanatory diagram of driving waveforms of the liquid crystal panel shown in FIG. VG is a voltage waveform applied to the gate signal line GL, VCOM is a voltage waveform applied to the common electrode, VDH is a voltage waveform applied to the odd-numbered drain signal line DL, and VDL is a voltage waveform applied to the even-numbered drain signal line DL. It is an applied voltage waveform.

Voltage waveform V applied to gate signal line GL
In G, the voltage of VDH and the voltage of VDL are written to each pixel electrode at the timing of changing to the high level and the low level in the cycle of one frame. In VDH and VDL, the polarity of the signal is inverted around VCOM in the cycle of one horizontal scan (1H). Further, the relationship between VDH and VDL is such that the polarity of the signal is inverted. By performing the driving method (dot inversion driving) shown in FIG. 22, the problem that the signal of the gate signal line DL or the signal of the drain signal line DL leaks to the pixel electrode irrelevant to them and the display quality is reduced is eliminated. .

Further, since the drain driver chip IC1 in the drain driver section 103 has a function of simultaneously outputting the odd-numbered output and the even-numbered output while changing the polarity, it performs dot inversion driving with good display image quality. Also, the frame area is reduced by moving the drain driver section 103 to one side of the liquid crystal display device.

Note that VCOM shown in FIG. 22 shows an ideal case where there is no coupling between the gate electrode and the source electrode of the thin film transistor TFT, and a bias for canceling the coupling is actually VCOM.
In addition to

A storage capacitor Cadd for holding the voltage of the pixel electrode is connected between the pixel electrode and a gate signal line GL for selecting a pixel electrode at the preceding stage of the pixel electrode. Note that a capacitor line different from the gate signal line GL may be provided, and the storage capacitor Cadd may be provided between the pixel electrode and the capacitor line. In this case, a voltage equivalent to the voltage applied to the common electrode is applied to the capacitance line.

FIG. 23 is an explanatory diagram of the flow of display data between the host computer and the controller of the liquid crystal display device. In the example shown in FIG. 3A, a display signal output from a display controller of a host computer (PC) is converted into two signals by data conversion. The two divided signals are respectively transmitted by the signal converter LVD on the transmission side.
The signal is input to an S (low voltage differential signal converter), converted into a differential signal, and sent to an interface connector CT1 of the liquid crystal display device through a cable.

In the controller section 101 (FIG. 20), each of the received two differential signals is input to the low-voltage differential signal converter LVDS on the receiving side, and is returned to the divided original display signal to be constituted by a thin film transistor TFT. The signals are input to a controller TCON that controls the scanning signal line driving circuit (gate driver 104) and video signal line driving circuit (drain driver 103) of the pixel.

The display signal sent from the display controller on the PC side to the controller TCON on the liquid crystal display device is digital data. The number of bits and the frequency at each stage are shown in the corresponding parts of FIG. The display signal output from the display controller is divided into two by data conversion, and the liquid crystal display receives the display signal divided into two, so that the frequency of the signal handled by the liquid crystal display decreases,
EMI (electromagnetic interference) is less likely to occur.

Also, the signal converter LVDS on the host PC side
Converts the digital data input in parallel into serial data and sends it to the liquid crystal display device side, and the signal converter LVDS on the liquid crystal display device converts the serial data into parallel data and reproduces the display signal. In addition, the number of terminals of the connector CT1 is reduced, and the connection reliability is improved. In addition, the number of wirings between the host PC and the liquid crystal display device is reduced, and the number of wirings through which a high-frequency current flows is reduced, so that EMI is less likely to occur.

The frequency of the differential signal output from the signal converter LVDS is reduced by compressing the information of the display signal to prevent the occurrence of EMI. As in this configuration example, a signal converter LV that converts a display signal sent as serial data to the liquid crystal display device into parallel data and reproduces the display signal.
By providing the DS, even if the number of display gradations increases, the connection reliability of the connector CT1 can be improved without increasing the number of terminals of the connector CT1.

FIG. 23B is a diagram for explaining another flow of display data between the host PC and the controller unit 101 on the liquid crystal display device side. In this example, a data modulator having a function of dividing a display signal and a function of converting parallel data and outputting a differential signal is provided on the host PC side. In this configuration, although the frequency of the differential signal is increased, the number of terminals of the connector CTI is further reduced, the connection reliability of the connector CTI is further increased, and the frame area of the liquid crystal display device is reduced by reducing the size of the interface substrate PCB. There is an effect that can be.

FIG. 24 is a perspective view of a notebook computer or a word processor on which a liquid crystal display device (liquid crystal display module) MDL is mounted. First, a signal from the information processing device goes from a connector located substantially at the center of the left interface substrate PCB to the display control integrated circuit element TCON, where the converted display data meets the multilayer flexible substrates FPC1 and FPC2. Flows to the peripheral circuit for the drain driver mounted by the COG method. 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.

As described above, the present invention has been specifically described based on the embodiments. However, the present invention is not limited to the above 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, and is not limited to the flip-chip type (COG type) in which a drive IC is directly mounted on a substrate, but can be similarly applied to a conventional type using TCP. It is.

[0139]

As described above, according to the present invention,
It is possible to provide a liquid crystal display device having a structure in which the thickness of the backlight device can be reduced so that the entire liquid crystal display device can be made thinner and the assembling work of the backlight device can be facilitated.

[Brief description of the drawings]

FIG. 1 is a sectional view of a main part of a backlight device for explaining a first embodiment of a liquid crystal display device of the present invention.

FIG. 2 is a perspective view of a main part of a backlight device for explaining a first embodiment of the liquid crystal display device of the present invention.

FIG. 3 is a sectional view of a main part of a backlight device for explaining a second embodiment of the liquid crystal display device of the present invention.

FIG. 4 is a sectional view of a main part of a backlight device for explaining a third embodiment of the liquid crystal display device of the present invention.

FIG. 5 is a sectional view of a main part of a backlight device for explaining a fourth embodiment of the liquid crystal display device of the present invention.

FIG. 6 is an exploded perspective view showing a state before the liquid crystal panel is covered with an upper frame constituting a housing of the liquid crystal display device.

FIG. 7 is an exploded perspective view showing a state before the liquid crystal display element is covered with an upper frame constituting a housing of the liquid crystal display device.

FIG. 8 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. 9 is an explanatory diagram of an interface substrate on which the liquid crystal display module of FIG. 8 is mounted on the back surface and side surfaces thereof.

FIG. 10 is a detailed explanatory view of an interface circuit board.

FIG. 11 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. 12 is a cross-sectional view taken along line A-A ′ of FIG.

FIG. 13 is a sectional view taken along line B-B ′ of FIG.

FIG. 14 is a sectional view taken along line C-C ′ of FIG. 8;

FIG. 15 is a sectional view taken along line D-D 'of FIG.

FIG. 16 is a plan view of a principal part for describing a detailed configuration near one pixel region of the liquid crystal panel.

FIG. 17 is a sectional view taken along the line IV-IV in FIG. 16;

18 is a sectional view taken along line VV in FIG.

19 is a sectional view taken along line VI-VI in FIG.

FIG. 20 is a block diagram showing a liquid crystal panel and circuits arranged on the outer periphery thereof.

FIG. 21 is a circuit configuration diagram of an equivalent circuit of a liquid crystal panel and a driving circuit and the like arranged on an outer peripheral portion thereof.

FIG. 22 is an explanatory diagram of driving waveforms of the liquid crystal panel shown in FIG.

FIG. 23 is an explanatory diagram of a flow of display data from the host computer to the controller of the liquid crystal display device.

FIG. 24 is a perspective view of another notebook computer or word processor on which a liquid crystal display module is mounted.

FIG. 25 is a perspective view illustrating a schematic structure of a conventional liquid crystal display device.

26 is a cross-sectional view illustrating a detailed structure of a main part along line XX in FIG. 25;

[Explanation of symbols]

 SHD Upper frame MCA Mold frame GLB Light guide LP Linear light source (cold cathode fluorescent tube) LS Light source reflector ALCV Concave RFS Reflective sheet RFS-E Reflective sheet extension BAT Double-sided adhesive tape PRS Prism sheet SPS Light diffuser SPS-E Light diffusion plate extension portion PJ convex portion RET concave portion SUB1 First substrate (lower substrate) SUB2 Second substrate (upper substrate) GL Gate signal line DL Drain signal line COM Common electrode wiring AR Display area ARR Drain wiring group.

────────────────────────────────────────────────── ───

[Procedure amendment]

[Submission date] August 30, 1999 (1999.8.3)
0)

[Procedure amendment 1]

[Document name to be amended] Statement

[Correction target item name] 0021

[Correction method] Change

[Correction contents]

[0021]

In particular, portable personal computers
If weight or thickness is an issue, such as
Edge-type backlights are specified. This side d
Ledge type backlight (hereinafter simply referred to as backlight)
Is composed of a light guide plate and a linear light source as described above.
There is a reflector on the back of the light guide plate and no light on the linear light source.
The light emitted from the linear light source is effectively incident on the light incident surface of the light guide plate.
A light source reflector is provided.

Continued on the front page (72) Inventor Tsutomu Isono 3681 Hayano, Mobara-shi, Chiba Prefecture Within Hitachi Device Engineering Co., Ltd. 2H091 FA14Z FA21Z FA32Z FA42Z FD11 GA13 LA11

Claims (4)

[Claims] 1. A liquid crystal display device in which a liquid crystal layer in which a gap between a first substrate and a second substrate is overlapped is sealed, and a backlight device installed on a back surface of the liquid crystal display device. In a liquid crystal display device in which a liquid crystal display element is fixed by a mold case to be housed and an upper frame, a linear light source in which the backlight device is arranged along a light incident surface which is at least one side edge of a light guide plate made of a transparent material. And a light source reflector for causing the light emitted from the linear light source to efficiently enter the light guide plate, a light diffusion plate laminated on the liquid crystal display element side of the light guide plate, and the liquid crystal display element of the light guide plate. A reflector provided so as to cover the entire surface on the opposite side.The reflector extends to the lower surface of the linear light source, and the linear light source is bent to the side opposite to the light incident surface of the light guide plate. Or A liquid crystal display device characterized in that the light source reflector by installing reflecting sheet separate to the upper surface of the linear light source. 2. A liquid crystal display device in which a liquid crystal layer in which a gap between a first substrate and a second substrate is overlapped is sealed, and a backlight device installed on a back surface of the liquid crystal display device. In a liquid crystal display device in which a liquid crystal display element is fixed by a mold case to be housed and an upper frame, a linear light source in which the backlight device is arranged along a light incident surface which is at least one side edge of a light guide plate made of a transparent material. And a light source reflector for causing the light emitted from the linear light source to efficiently enter the light guide plate, a light diffusion plate laminated on the liquid crystal display element side of the light guide plate, and the liquid crystal display element of the light guide plate. A reflector provided so as to cover the entire surface on the opposite side.The reflector extends to the lower surface of the linear light source, and the upper surface from the side opposite to the light incident surface of the light guide plate with respect to the linear light source. Overturn The liquid crystal display device as bent to be characterized in that the light source reflector. 3. A liquid crystal display device in which a liquid crystal layer in which a gap between a first substrate and a second substrate is overlapped is sealed, and a backlight device installed on the back of the liquid crystal display device. In a liquid crystal display device in which a liquid crystal display element is fixed by a mold case to be housed and an upper frame, a linear light source in which the backlight device is arranged along a light incident surface which is at least one side edge of a light guide plate made of a transparent material. And a light source reflector for causing the light emitted from the linear light source to efficiently enter the light guide plate, a light diffusion plate laminated on the liquid crystal display element side of the light guide plate, and the liquid crystal display element of the light guide plate. A reflector provided so as to cover the entire surface on the opposite side.The reflector extends to the lower surface of the linear light source, and the linear light source is bent to the side opposite to the light incident surface of the light guide plate. ,Previous The liquid crystal display device, characterized in that by extending the light diffusion plate on the upper surface of the linear light source was the light source reflector. 4. A projection is provided at a part of an edge of the light diffusion plate, the prism sheet, and the reflection plate other than the light incident surface side, and a recess is provided at a position corresponding to the projection of the mold case. 4. A predetermined installation position is secured by engaging said convex portion with said concave portion.
3. The liquid crystal display device according to 1.