JP2001117084A - Liquid crystal display device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent ripple-shaped visible defect from being generated in the vicinity of the attached part of the mounted instrument due to external shock. SOLUTION: The liquid crystal display device MDL is provided with a recessing part ALV that stores a light transmission plate GLB constituting a backlight BM in the most part of the central region of the lower case MCA. Simttltaneously the device MDL is provided with a bank part DAM that holds an optical compensation sheet OPS between itself and a liquid crystal panel PNL at least on a part of its peripheral part. A reflection sheet RFS and a reflection plate ALS are arranged on the rear side of the light transmission plate GLB to be stored in the recessing part ALV in this order. An inserter INS that is a female screw to fix the device MDL to the mounted instrument is laid underground in the bank part DAM. A chamfered part COF is formed at least on a part of the apical angle of the bank part DAM in which the inserter INS is laid underground opposite to the optical compensation sheet OPS.

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 display defects caused by an external impact via a mounting portion with a mounting device are suppressed.

[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.

There are two types of liquid crystal display devices, one using a simple matrix type liquid crystal panel using a liquid crystal panel sandwiching a liquid crystal layer between a pair of substrates formed with parallel electrodes formed so as to cross each other on each inner surface. An active matrix type liquid crystal display device using a liquid crystal panel having a switching element for selecting a pixel unit on one of the substrates is known.

An active matrix type liquid crystal panel, as represented by a twisted nematic (TN) mode, uses a liquid crystal panel in which an electrode group for pixel selection is formed on a pair of upper and lower substrates, a so-called vertical electric field mode ( A so-called lateral electric field method (generally referred to as an IPS method) using 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, and a TN method.
There is.

The former TN mode liquid crystal panel is composed of a pair (a first substrate (lower substrate) and a second substrate (upper substrate)).
The liquid crystal is twisted and oriented, for example, by 90 ° in the substrate, 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 intersected with the rubbing direction. And two polarizing plates.

In such a TN type active matrix type liquid crystal panel, when no voltage is applied, 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 emitting side polarizing plate. When the transmission axis of coincides with the azimuth angle of the linearly polarized light, all of 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 panel that switches layers 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).

In the initial state, the liquid crystal layer of the IPS mode liquid crystal panel has a homogeneous orientation parallel to the substrate surface, and has a plane parallel to the substrate, and the director of the liquid crystal layer is parallel or slightly parallel to the electrode wiring direction when no voltage is applied. With the voltage 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 voltage, and the director direction of the liquid crystal layer is compared to the director direction when no voltage is applied. The liquid crystal layer at the time of applying the voltage,
The azimuth of the polarized light is rotated by 90 ° like a half-wave plate, and the transmission axis of the exit-side deflecting plate and the azimuth of the polarized light coincide with each other, and white display is performed.

The IPS mode liquid crystal panel 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. 5-5052).
No. 47).

[0011] A color filter system is mainly used in a full-color liquid crystal display device using the above-described various liquid crystal panels. 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 is applicable to the various liquid crystal display devices described above.

In mounting such a liquid crystal display device on an information device such as a personal computer, a mounting hole is provided on a surface of a corner portion of the liquid crystal display device, and the liquid crystal display device is fixed to the information device via a screw or the like. However, when mounting a so-called narrow-frame large-screen liquid crystal display device on a device such as a personal computer, there is no room for providing the mounting hole as described above, so the mounting hole is provided on the side surface of the liquid crystal display device, and the A side mounting method for fixing is known.

FIGS. 13A and 13B are external views illustrating an example of a liquid crystal display device, wherein FIG. 13A is a front view, FIG. 13B is a left side view,
(C) is a right side view. This liquid crystal display device MDL (also referred to as a liquid crystal module) has a liquid crystal panel PNL, a backlight, an optical compensation sheet made of a prism sheet or a diffusion sheet, and a reflection sheet or a reflection plate laminated to form an upper frame SHD made of a metal plate. Generally, it is integrated by being sandwiched by a lower frame MCA of a plastic mold.

The liquid crystal display device MDL shown in FIG. 13 is attached to a mounting device by the above-described side mount method. In this side mount method, a screw hole TH extending from the upper frame SHD to the lower frame MCA is provided on a side surface of the liquid crystal display device MDL. It is attached through a screw between the hole. In addition, CT is a connector for introducing a display signal from the personal computer body.

The screw holes of the lower frame CA are buried with female screws called inserters, and the upper frame SHD side is a through hole. The screw is screwed into the inserter from the mounting device side through this through hole.

FIG. 14 is a schematic diagram showing a state in which the liquid crystal display device is mounted on a lid of a mounting device by a side mount method.
In this configuration example, the cover CASE of the mounting device is provided with a highly rigid substantially U-shaped reinforcing member ST that is preferably a metal plate, and a screw SC is formed from the reinforcing member ST by using the liquid crystal display device MD.
L to be fixed.

The reinforcing member ST has a hinge HNG for opening and closing the cover CASE on a personal computer body on which a keyboard and the like are mounted. In this example, the reinforcing member ST has a U-shape having open arms on the left and right side surfaces of the liquid crystal display device MDL. However, the reinforcing member ST is not limited to such a shape, but may be an independent arm for each of the left and right side surfaces. There is also known an individual member.

FIG. 15 is a schematic cross-sectional view taken along the line BB of FIG. The liquid crystal display device MDL has two glass substrates SU.
B1 and SUB2 sandwich a liquid crystal layer and a backlight BL installed on the back of a liquid crystal panel PNL and an upper frame SHD.
And the lower frame MCA. The backlight BL propagates light from a not-shown linear lamp (generally, a cold-cathode fluorescent lamp CFL) to propagate the liquid crystal panel PN.
A light guide plate GLB composed of a transparent plastic plate for directing light in the L direction, an optical compensation sheet OPS composed of a prism sheet and a diffusion plate laminated on the liquid crystal panel PNL side of the light guide plate GLB, and a reflection disposed on the back surface of the light guide plate GLB. It is composed of a sheet RFS and a reflector ALS preferably made of an aluminum plate.

The backlight BL is provided with a reflector ALS in a concave portion ALV formed in most of the central region of the lower frame MCA.
And a reflection sheet RFS, and a light guide plate GLB
, And the optical sheet OPS is placed on the upper part. This optical sheet OPS is a lower frame MCA
Upper surface of the bank DAM formed around the periphery of the optical compensatory sheet O
It is sandwiched between the liquid crystal panel PNL via the PS.

An inserter INS is buried in the bank DAM of the lower frame MCA, a screw hole TH is provided in the upper frame SHD, and a screw SC is passed through the screw hole of the reinforcing member ST to form an inserter INS serving as a female screw. And screwed into it.

[0021]

In such a fixing structure, when a shock is applied from the outside, the shock is transmitted from the reinforcing member to the lower frame of the liquid crystal display device via the screw of the mounting portion. As a result, there is a problem that ripple-like display defects occur on the display surface of the liquid crystal panel.

FIG. 16 is a schematic cross-sectional view of the vicinity of the line BB in FIG. 14 for explaining the cause of the occurrence of ripple-like display defects generated on the display surface of the liquid crystal panel. The liquid crystal display device MDL is fixed to the inserter INS embedded in the lower frame MCA with a screw SC inserted from the reinforcing member ST. At this time, for example, an impact when a keyboard of a personal computer as a mounting device is hit is applied to the liquid crystal display device MDL from the reinforcing member ST.
To the bank DAM of the lower frame MCA. Since the lower frame MCA is a plastic mold, and the inserter INS portion of the bank DAM into which the screw SC is screwed is firmly fixed to the reinforcing member ST, this impact optically compensates the bank DAM as shown by the arrow in the figure. The sheet OPS is pushed up to push up the liquid crystal panel PNL, or the light guide plate GLB.
To push up the liquid crystal panel PNL.

As a result, the cell gap of the pushed-up portion of the liquid crystal panel PNL changes due to the vibration of the impact, Δnd of the portion changes at random, and a display defect formed by rippled shading on the display screen. Occurs.

FIG. 17 is a schematic diagram for explaining an example of a ripple-like display defect occurring on the display surface of the liquid crystal panel. The inserter INS portion of the bank DAM into which the screw SC of the lower frame MCA of the liquid crystal display device MDL is screwed is firmly fixed to the reinforcing member ST.
nd is easier to change than other parts. Therefore, as shown in FIG. 17, a ripple-shaped display defect occurs in the inserter INS portion. In addition, such a display defect is as follows.
The liquid crystal panel PNL is not limited to the one mounted by the side mount method, but may be mounted on the mounting device from the front side of the liquid crystal display device MDL.
In a structure in which d partially changes, the same may occur. Such a display failure is likely to occur in a frame structure accompanying a recent reduction in thickness.

An object of the present invention is to solve the above-mentioned problems of the prior art and to provide a liquid crystal display device in which ripple-like display defects caused by, for example, a key operation of a keyboard or another external impact are suppressed. is there.

[0026]

In order to achieve the above object, the present invention provides a liquid crystal display device comprising a liquid crystal panel,
In the structure in which the backlight structure is laminated, the shape structure of the lower frame or the structure of the reflector is improved so that the liquid crystal panel is not pushed up by the backlight.

Hereinafter, a typical configuration of the liquid crystal display device according to the present invention having the above structure will be described. (1): A liquid crystal display device in which a backlight is laminated on the back surface of a liquid crystal panel via an optical compensation sheet, and is fixedly held between an upper case and a lower case. A light guide plate having a recess for accommodating a light guide plate constituting a backlight, and having at least a part of a peripheral portion thereof a ridge for sandwiching the optical compensation sheet between the liquid crystal panel and the light guide plate for accommodation in the recess. A reflection sheet and a reflection plate are arranged in this order on the back surface of the bank, and a mounting portion for fixing the liquid crystal display device to mounting equipment is provided on the bank, and the optical compensation sheet of the bank on which the mounting portion is formed is provided. A chamfer was formed on at least a part of the facing apex angle.

By providing the chamfered portion on the bank portion, even if the bank portion moves toward the liquid crystal panel due to an external impact, the liquid crystal panel is not pushed up by the chamfered portion. Therefore, a ripple-like display defect unlike the related art does not occur.
The chamfer is preferably applied to the whole area in the longitudinal direction of the embankment. However, when the mechanical strength of a portion to be attached to the reinforcing member is reduced, the chamfer is formed avoiding the embedded portion of the inserter. It may be.

(2) A liquid crystal display device in which a backlight is laminated on the rear surface of a liquid crystal panel via an optical compensation sheet, and is fixed by being sandwiched between an upper case and a lower case. Has a recess for accommodating the light guide plate constituting the backlight, and at least a part of the periphery thereof has a bank portion for sandwiching the optical compensation sheet between the liquid crystal panel and the recess. A reflection sheet and a reflection plate are arranged in this order on the back surface of the light guide plate, and a screw hole for attaching the liquid crystal display device to a mounting device is provided on a side surface of the bank, and the bank of the bank having the screw hole is formed. A chamfer was formed on at least a part of the vertex angle facing the optical compensation sheet.

By providing the chamfered portion on the bank portion, even if the bank portion moves toward the liquid crystal panel due to an external impact, the liquid crystal panel is not pushed up by the chamfered portion. Therefore, a ripple-like display defect unlike the related art does not occur.
The chamfered portion is preferably applied to the entire longitudinal direction of the embankment, but when the mechanical strength of the buried portion of the inserter is reduced, the chamfered portion is formed avoiding the buried portion of the inserter. Is also good.

(3): A liquid crystal display device in which a backlight is laminated on the back surface of a liquid crystal panel via an optical compensation sheet and fixed between an upper case and a lower case, and most of the central region of the lower case. Has a recess for accommodating the light guide plate constituting the backlight, and at least a part of the periphery thereof has a bank portion for sandwiching the optical compensation sheet between the liquid crystal panel and the recess. A reflection sheet and a reflection plate are arranged in this order on the back surface of the light guide plate, and the bank has a mounting portion for fixing the liquid crystal display device to mounting equipment, and the reflection plate near the mounting portion is removed. Thus, a gap was formed between the rear surface of the light guide plate and the upper surface of the concave portion.

Generally, an aluminum plate or an aluminum vapor-deposited plate is used as the reflection plate. By removing the reflection plate along or near the mounting portion, a gap is formed between the lower case and the light guide plate. You. For this reason, even if the bank moves in a direction to push up the light guide plate due to an external impact, it is difficult to abut the light guide plate. Therefore, a ripple-like display defect unlike the related art does not occur.

(4) A liquid crystal display device in which a backlight is laminated on the back surface of a liquid crystal panel via an optical compensation sheet, and is fixed by being sandwiched between an upper case and a lower case. Has a recess for accommodating the light guide plate constituting the backlight, and at least a part of the periphery thereof has a bank portion for sandwiching the optical compensation sheet between the liquid crystal panel and the recess. A reflection sheet and a reflection plate are arranged in this order on the back surface of the light guide plate to be formed, and a screw hole for mounting the liquid crystal display device to a mounting device is provided on a side surface of the bank, and the reflection plate near the screw hole is removed. Thus, a gap was formed between the rear surface of the light guide plate and the upper surface of the concave portion.

As described above, a gap is formed between the lower case and the light guide plate by omitting the reflector along or near the mounting portion. For this reason, even if the bank moves in a direction to push up the light guide plate due to an external impact, it is difficult to abut the light guide plate. Therefore, a ripple-like display defect unlike the related art does not occur.

(5): The reflector in the vicinity of the mounting portion in (1) was removed to form a gap between the back surface of the light guide plate and the upper surface of the concave portion.

The effect of (1) and the effect of (3) are synergistic, and the ripple-like display failure is more effectively suppressed.

(6): The reflector near the screw hole in (2) was removed to form a gap between the back surface of the light guide plate and the upper surface of the recess.

The effect of the above (2) and the effect of the above (4) are synergistic, and the ripple-like display failure is more effectively suppressed.

(7): A liquid crystal display device in which a backlight is laminated on the back surface of a liquid crystal panel via an optical compensation sheet and fixed between an upper case and a lower case, and most of the central region of the lower case. Has a recess for accommodating the light guide plate constituting the backlight, and at least a part of the periphery thereof has a bank portion for sandwiching the optical compensation sheet between the liquid crystal panel and the recess. A reflection sheet and a reflection plate are arranged in this order on the back surface of the light guide plate to be mounted, and the bank has a mounting portion for fixing the liquid crystal display device to a mounting device, and a recessed portion at least in the vicinity of the mounting portion of the concave portion. And a gap was formed between the rear surface of the light guide plate and the upper surface of the concave portion.

Since a gap is formed between the lower frame and the light guide plate by the recess formed at least in the vicinity of the attachment portion of the concave portion, even if the levee moves in the direction of pushing up the light guide plate by an external impact, it is guided. It is difficult to contact the light plate.
Therefore, a ripple-like display defect unlike the related art does not occur. The depression may be formed over the entire area along the end of the light guide plate, or may be formed only near the mounting part.

(8) A liquid crystal display device in which a backlight is laminated on the back surface of a liquid crystal panel via an optical compensation sheet, and is fixed by being sandwiched between an upper case and a lower case. Has a recess for accommodating the light guide plate constituting the backlight, and at least a part of the periphery thereof has a bank portion for sandwiching the optical compensation sheet between the liquid crystal panel and the recess. A reflection sheet and a reflection plate are arranged in this order on the back surface of the light guide plate, and a screw hole for attaching the liquid crystal display device to a mounting device is provided on a side surface of the bank, and the recess falls into at least the vicinity of the attachment portion of the concave portion. And a gap was formed between the rear surface of the light guide plate and the upper surface of the concave portion.

Similarly to the above (7), a gap is formed between the lower frame and the light guide plate by the recess formed at least in the vicinity of the screw hole of the concave portion (in the vicinity of the buried portion of the inserter). Even if the bank moves in a direction to push up the light guide plate due to the impact, it becomes difficult to abut the light guide plate. Therefore, a ripple-like display defect unlike the related art does not occur.

(9): A chamfered portion was formed at least at a part of the vertex angle of the embankment formed with the mounting portion in (7) facing the optical compensation sheet.

The effect of the above (7) and the effect of the above (1) are synergistically combined to more effectively suppress the ripple-like display failure.

(10): A chamfered portion was formed at least at a part of the vertex angle of the embankment formed with the attachment portion in (8), facing the optical compensation sheet.

The effect of (8) and the effect of (2) are synergistic, and the ripple-like display failure is more effectively suppressed.

It should be noted that the present invention is not limited to the above configuration, and does not depart from the technical idea of the present invention.
Various modifications are possible.

Other objects and configurations of the present invention will become apparent from the description of the embodiment below.

[0049]

Embodiments of the present invention will be described below in detail with reference to the accompanying drawings. FIG. 1 is a sectional view of a principal part, similar to FIG. 15, illustrating a first embodiment of a liquid crystal display device according to the present invention. Configuration of Liquid Crystal Panel PNL and Backlight BL and Reinforcing Member S for Mounting Equipment
The fixing structure with T has been described with reference to FIG. In FIG. 1, INS is an inserter (female screw) buried in the bank of the lower frame MCA.
DL is from the reinforcing member ST of the mounting equipment to the upper frame SHD.
Screw SC is screwed through the screw hole TH.

In the present embodiment, the bank D of the lower frame MCA
A chamfered portion COF was formed at the apex angle facing the optical compensation sheet OPS of AM. Due to the chamfered portion COF, the bank DAM does not push up the optical compensation sheet OPS even if the lower frame MCA moves as described with reference to FIG. Therefore, the cell gap of the liquid crystal panel PNL does not fluctuate, and the occurrence of ripple-shaped display defects centered on the embedded portion of the inserter INS as in the related art is suppressed.

FIG. 2 is a plan view of a main part of the lower frame constituting the liquid crystal display device as viewed from the direction of arrow A in FIG. In the present embodiment, as shown in (a), the chamfered portion COF is formed so as to avoid the vicinity of the inserter buried in the bank DAM of the lower frame MCA. (B) shows a case where a chamfered portion COF is applied to the entire area in the length direction of the bank portion DAM of the lower frame MCA.

FIG. 2A shows a case where the mechanical strength of the embankment DAM is reduced by burying the inserter INS, and FIG. 2B shows a case where the mechanical strength is reduced by burying the inserter INS. There is no fear.

In any case, even if the bank DAM moves toward the liquid crystal panel due to an external impact, the chamfered portion CO
Due to F, the bank DAM does not come into contact with the liquid crystal panel (directly the optical compensation sheet OPS), and the liquid crystal panel is not pushed up. Therefore, a ripple-like display defect unlike the related art does not occur.

FIGS. 3A and 3B are explanatory views of a liquid crystal display device according to a second embodiment of the present invention. FIG. 3A is a cross-sectional view of a main part similar to FIG. 1, and FIG. It is a partial plan view. In this embodiment, the bank DAM of the reflector ALS constituting the backlight BL of the lower frame MCA of the liquid crystal display device is used.
A missing portion CFF in which at least a part of the side is missing is formed. The reflection plate ALS is generally formed by depositing aluminum on an aluminum plate or a resin sheet. The missing portion CFF of the reflector ALS is formed in a portion facing the inserter INS embedded in the bank of the lower frame MCA. The size of the missing portion CFF may be selected according to the mechanical strength of each component constituting the liquid crystal display device.

With this configuration, the bank D
Even if AM moves toward the liquid crystal panel, the light guide plate GLB does not push up the liquid crystal panel (directly the optical compensation sheet OPS) because there is a gap due to the missing portion CFF of the reflector RFS. Therefore, a ripple-like display defect unlike the related art does not occur.

FIGS. 4A and 4B are explanatory views of a liquid crystal display device according to a third embodiment of the present invention. FIG. 4A is a cross-sectional view of a main part similar to FIG. 3, and FIG. It is a partial plan view. In this embodiment, the bank DAM of the reflector ALS constituting the backlight BL of the lower frame MCA of the liquid crystal display device is used.
A cut-off portion CFF which lacks at least a part of the side is formed, and a chamfered portion OF similar to FIG. 1 is formed at least at a part of a vertex angle of the bank portion DAM of the lower frame MCA facing the optical compensation sheet OPS. Things.

The chamfered portion COF formed in the embankment DAM is not limited to the portion avoiding the embedded portion of the inserter INS as shown in FIG. 4B, and the mechanical strength of the embankment DAM can be sufficiently ensured. In this case, it may be formed in the entire longitudinal direction of the bank DAM.

With the configuration of the present embodiment, in addition to the effect of the configuration of FIG. 1, the effect of the configuration of FIG. 3 is synergistic, and the occurrence of ripple-shaped display defects can be suppressed more reliably.

FIG. 5 is a sectional view of a principal part, similar to FIG. 1, for explaining a fourth embodiment of the liquid crystal display device according to the present invention. In the present embodiment, a depression GV is formed on the bank DAM side of the recess ALV for storing the backlight BL of the lower frame MCA in FIG. By forming the recess GV, the lower frame MC
A does not push up the light guide plate GLB.
The chamfered portion COF formed in the AM is prevented from pushing up the liquid crystal panel PNL, and the occurrence of ripple-shaped display defects can be suppressed.

Depending on the mechanical strength of the components of the liquid crystal display device, only the depression GV formed on the bank DAM side of the recess ALV may be used.

FIG. 6 is a sectional view of a principal part for explaining a fifth embodiment of the liquid crystal display device according to the present invention. In the present embodiment, the mounting method of the liquid crystal display device to the reinforcing member ST of the mounting device is a screw fixing method from the surface direction different from the above-described embodiments.

Even in this mounting method, an external impact may cause a ripple-like display failure of the liquid crystal panel PNL. In the present embodiment, the backlight B of the lower frame MCA
The depression G on the bank DAM side of the recess ALV for storing the L
V and a chamfered portion COF similar to that shown in FIG.

The liquid crystal display device having the mounting structure shown in FIG. 6 is different from the liquid crystal display device shown in FIG.
Alternatively, the missing portion CFF may be formed in the reflector RFS in the side mount system described with reference to FIG. In addition, the chamfered portion COF of the bank DAM and the missing portion CF of the reflector RFS are provided.
F, the depression GV of the lower frame MCA may be used alone or in combination.

Next, an example of a liquid crystal display device to which the present invention described in each of the above embodiments is applied, an example of a mounting device thereof, and an example of a driving method will be described.

FIG. 7 is an external view of a notebook personal computer as an example of an electronic apparatus on which the liquid crystal display device according to the present invention is mounted. In this notebook computer, a keyboard section (main body section) and a display section are connected by a hinge, and the keyboard section has a C
A host computer including a PU or the like and a keyboard are mounted, and the liquid crystal display device MDL according to the present invention is mounted on the display unit.

Drive circuit boards PCB1, PCB1 are provided around the liquid crystal panel PNL constituting the liquid crystal display device MDL.
2, a PCB 3, an inverter power supply IV for backlight, and the like. In addition, CT is a connector connected to the host side, and TCON is a control circuit that generates signal processing for displaying an image on the liquid crystal panel PNL and a timing signal based on a display signal input from the host side.

The liquid crystal display device according to the present invention can be used not only for a portable personal computer such as a notebook type as shown in FIG. 7, but also for a stationary personal computer such as a desktop monitor and a display device of other devices. Needless to say.

FIG. 8 is a plan view showing one pixel of a liquid crystal panel constituting the liquid crystal display device of the present invention and its peripheral structure.
FIG. 9 is a cross-sectional view of a thin film transistor (TFT) portion taken along line 3-3 in FIG. FIG. 8 is a configuration diagram of one pixel in the vicinity of a so-called TN type active matrix liquid crystal display device. Each pixel includes two adjacent scanning signal lines (gate signal lines or horizontal signal lines) GL and two adjacent signal lines. (In a region surrounded by four signal lines) with the video signal line (drain signal line or vertical signal line) DL.

Each pixel includes a thin film transistor TFT, a transparent pixel electrode ITO1, and a storage capacitor Cadd. The scanning signal lines GL extend in the column direction, and a plurality of the scanning signal lines GL are arranged in the row direction. The video signal lines DL extend in the row direction, and a plurality of video signal lines DL are arranged in the column direction.

As shown in FIG. 9, a thin film transistor TFT and a transparent pixel electrode ITO1 are formed on the lower transparent glass substrate (lower glass substrate) SUB1 side with respect to the liquid crystal LC, and the upper transparent glass substrate (upper glass substrate) SUB
On the second side, a color filter FIL and a pattern BM of a light-shielding black matrix are formed.

The upper and lower transparent glass substrates SUB2, SUB1 have a thickness of, for example, about 0.7 mm, and are formed thereon with a film quality such as a scanning signal line GL and a light shielding film (black matrix) BM. I have. Upper transparent glass substrate SUB2
The light shielding film BM, the color filter FIL, and the upper alignment film ORI2 are sequentially laminated on the inner surface (the liquid crystal LC side).

FIG. 10 is an explanatory diagram of a configuration of a general active matrix type liquid crystal display device to which the present invention is applied and a driving system. This type of liquid crystal display device has a liquid crystal panel P
NL and a data line (also referred to as a drain signal line or a drain line) driving circuit (IC) around the liquid crystal panel PNL.
Chip), that is, a drain driver DDR, and a scanning line (also referred to as a gate signal line or a gate line) driving circuit (IC chip), that is, a gate driver GDR. These drain driver DDR and gate driver GDR have display data for image display, A display control unit CRL, which is a display control unit for supplying a clock signal, a gray scale voltage, and the like, and a power supply circuit PWU are provided.

Display data from the main unit (external signal source such as a computer, a personal computer, and a television receiving circuit) and a control signal clock, a display timing signal, and a synchronization signal are input to the display control device CRL. The display control device CRL includes a gradation reference voltage generator, a timing controller TCON, and the like, and converts display data from the outside into data in a format suitable for display on the liquid crystal panel PNL.

Display data and clock signals for the gate driver GDR and the drain driver DDR are supplied as shown. The carry output of the previous stage of the drain driver DDR is directly supplied to the carry input of the next stage drain driver.

FIG. 11 is a block diagram showing a schematic configuration of each driver of the liquid crystal panel and a signal flow. The drain driver DDR includes a data latch unit for display data such as a video (image) signal and an output voltage generation circuit. Also,
The gradation reference voltage generation unit HTV, multiplexer MPX, common voltage generation unit CVD, common driver CDD, level shift circuit LST, gate-on voltage generation unit GOV, gate-off voltage generation unit GFD, and DC-DC converter D / D are shown in FIG. The power supply circuit PWU is provided.

FIG. 12 is a timing chart showing display data input from the signal source (main body) to the display control device and signals output from the display control device to the drain driver and the gate driver. The display control device CRL receives a control signal (clock signal, display timing signal, synchronization signal) from a signal source, and transmits a clock D1 (CL1), a shift clock D2 (CL2), and display data as control signals to the drain driver DDR. At the same time, a frame start instruction signal FLM, a clock G (CL3) and display data are generated as control signals to the gate driver GDR.

In the system using the low voltage differential signal (LVDS signal) for transmitting the display data from the signal source,
The LVDS signal from the LVDS transmission circuit on the signal source side is converted into an original signal by an LVDS receiving circuit mounted on a board (generally called an interface board) on which the display control device is mounted, and then the gate driver GDR and Supply to the drain driver DDR.

As apparent from FIG. 12, 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 or the like. High frequency of 40 MHz (megahertz).

Although the present invention has been specifically described based on the embodiments, the present invention is not limited to the above-described embodiments, and various modifications can be made without departing from the gist of the present invention. Needless to say. For example, in the above embodiments, the present invention has been described as being applied to a TN type active matrix type liquid crystal display device. However, an IPS type active matrix type liquid crystal display device, a simple matrix type, and other types of liquid crystal display devices are used. The same applies to devices.

[0080]

As described above, according to the present invention,
The structure of the lower frame and the structure of the reflector have been improved so that the backlight does not push up the liquid crystal panel in the structure in which the liquid crystal panel constituting the liquid crystal display device and its backlight structure are laminated. Accordingly, it is possible to provide a liquid crystal display device in which ripple-like display defects generated on the screen of the liquid crystal panel near the mounting portion of the liquid crystal display device due to a keyboard operation or another external impact are suppressed.

[Brief description of the drawings]

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

FIG. 2 is a plan view of a main part of the lower frame constituting the liquid crystal display device as viewed from the direction of arrow A in FIG. 1;

FIG. 3 is an explanatory view of a second embodiment of the liquid crystal display device according to the present invention.

FIG. 4 is an explanatory view of a third embodiment of the liquid crystal display device according to the present invention.

FIG. 5 is a cross-sectional view of a principal part explaining a fourth embodiment of the liquid crystal display device according to the present invention.

FIG. 6 is a cross-sectional view of a principal part explaining a fifth embodiment of the liquid crystal display device according to the present invention.

FIG. 7 is an external view of a notebook computer which is an example of an electronic device on which the liquid crystal display device according to the present invention is mounted.

FIG. 8 is a plan view illustrating a configuration of one pixel of a liquid crystal panel constituting the liquid crystal display device of the present invention and its periphery.

9 is a cross-sectional view of a thin film transistor (TFT) taken along line 3-3 in FIG.

FIG. 10 is a diagram illustrating a configuration of a general active matrix type liquid crystal display device to which the present invention is applied and a driving system.

FIG. 11 is a block diagram showing a schematic configuration of each driver of the liquid crystal panel and a signal flow.

FIG. 12 is a timing chart showing display data input from a signal source (main body) to a display control device and signals output from the display control device to a drain driver and a gate driver.

FIG. 13 is an external view illustrating an example of a liquid crystal display device.

FIG. 14 is a schematic diagram showing a state in which the liquid crystal display device is mounted on a lid of a mounting device by a side mount method.

FIG. 15 is a schematic cross-sectional view of the vicinity of line BB in FIG. 14;

16 is a schematic cross-sectional view of the vicinity of line BB in FIG. 14 for explaining the cause of the occurrence of a ripple-shaped display defect generated on the display surface of the liquid crystal panel.

FIG. 17 is a schematic diagram illustrating an example of a ripple-like display defect that occurs on a display surface of a liquid crystal panel.

[Explanation of symbols]

 MDL Liquid crystal display device (liquid crystal module) PNL Liquid crystal panel OPS Optical compensation sheet SHD Upper frame TH Screw hole MCA Lower frame GLB Light guide plate RFS Reflection sheet ALS Reflection plate ST Reinforcement member SC Screw INS Inserter DAM Embankment COF Chamfer CFF Missing portion GV ALV recess.

 ──────────────────────────────────────────────────の Continued on the front page (72) Inventor Akinori Matsuda 3681 Hayano, Mobara-shi, Chiba F-term in Hitachi Device Engineering Co., Ltd. (reference) 2H091 FA02Y FA08X FA08Z FA11Z FA14Z FA23Z FA41Z GA13 HA07 LA02 5G435 AA00 BB12 BB15 EE03 EE04 EE08 EE33 FF03 FF08 FF13 GG12 LL07

Claims (10)

[Claims] 1. A liquid crystal display device in which a backlight is laminated on the back surface of a liquid crystal panel via an optical compensation sheet, and is fixedly held between an upper case and a lower case. A guide for accommodating the light guide plate constituting the backlight, and a ridge for holding the optical compensatory sheet between the liquid crystal panel and the liquid crystal panel at least in a part of the periphery thereof. A reflection sheet and a reflection plate are arranged in this order on the back surface of the light plate, and the bank has a mounting portion for fixing the liquid crystal display device to mounting equipment, and the optical compensation sheet of the bank formed with the mounting portion. A chamfered portion is formed at least at a part of the apex angle facing the liquid crystal display device. 2. A liquid crystal display device wherein a backlight is laminated on the back surface of a liquid crystal panel via an optical compensation sheet, and is fixed by being sandwiched between an upper case and a lower case. A guide for accommodating the light guide plate constituting the backlight, and a ridge for holding the optical compensatory sheet between the liquid crystal panel and the liquid crystal panel at least in a part of the periphery thereof. A reflection sheet and a reflection plate are arranged in this order on the back surface of the light plate, and a screw hole for mounting the liquid crystal display device to a mounting device is provided on a side surface of the bank, and the optical compensation of the bank having the screw hole is formed. A liquid crystal display device comprising a chamfer formed at least at a part of a vertex angle facing a sheet. 3. A liquid crystal display device in which a backlight is laminated on the back surface of a liquid crystal panel via an optical compensation sheet, and is fixedly held between an upper case and a lower case. A guide for accommodating the light guide plate constituting the backlight, and a ridge for holding the optical compensatory sheet between the liquid crystal panel and the liquid crystal panel at least in a part of the periphery thereof. A reflection sheet and a reflection plate are arranged in this order on the back surface of the light plate, and a mounting portion for fixing the liquid crystal display device to a mounting device is provided on the bank, and the reflection plate near the mounting portion is removed to remove the reflection plate. A liquid crystal display device, wherein a gap is formed between the back surface of the light guide plate and the upper surface of the recess. 4. A liquid crystal display device in which a backlight is laminated on the back surface of a liquid crystal panel via an optical compensation sheet, and is fixedly held between an upper case and a lower case. A guide for accommodating the light guide plate constituting the backlight, and a ridge for holding the optical compensatory sheet between the liquid crystal panel and the liquid crystal panel at least in a part of the periphery thereof. A reflection sheet and a reflection plate are arranged in this order on the back surface of the light plate, and a screw hole for attaching the liquid crystal display device to a mounting device is provided on a side surface of the bank, and the reflection plate near the screw hole is removed. A liquid crystal display device, wherein a gap is formed between the rear surface of the light guide plate and the upper surface of the concave portion. 5. The liquid crystal display device according to claim 1, wherein the reflector near the mounting portion is removed to form a gap between the back surface of the light guide plate and the upper surface of the recess. 6. The liquid crystal display device according to claim 2, wherein the reflector near the screw hole is removed to form a gap between the back surface of the light guide plate and the upper surface of the recess. 7. A liquid crystal display device in which a backlight is laminated on the back surface of a liquid crystal panel via an optical compensation sheet, and is fixedly held between an upper case and a lower case. A guide for accommodating the light guide plate constituting the backlight, and a ridge for holding the optical compensatory sheet between the liquid crystal panel and the liquid crystal panel at least in a part of the periphery thereof. A reflection sheet and a reflection plate are arranged in this order on the back surface of the light plate, and the bank has a mounting portion for fixing the liquid crystal display device to a mounting device, and a depression portion is formed at least in the vicinity of the mounting portion of the concave portion. And a gap formed between the rear surface of the light guide plate and the upper surface of the concave portion. 8. A liquid crystal display device in which a backlight is laminated on the rear surface of a liquid crystal panel via an optical compensation sheet, and is fixedly held between an upper case and a lower case. A guide for accommodating the light guide plate constituting the backlight, and a ridge for holding the optical compensatory sheet between the liquid crystal panel and the liquid crystal panel at least in a part of the periphery thereof. A reflection sheet and a reflection plate are arranged in this order on the rear surface of the light plate, and a screw hole for mounting the liquid crystal display device to a mounting device is provided on a side surface of the bank, and a recessed portion is formed at least in the vicinity of the mounting portion of the concave portion. A liquid crystal display device, wherein a gap is formed between the rear surface of the light guide plate and the upper surface of the concave portion. 9. The liquid crystal display device according to claim 7, wherein a chamfered portion is formed on at least a part of an apex angle of the bank portion where the mounting portion is formed, the vertex facing the optical compensation sheet. 10. The liquid crystal display device according to claim 8, wherein a chamfered portion is formed on at least a part of an apex angle of the embankment portion where the mounting portion is formed, the vertex facing the optical compensation sheet.