KR20010040065A - Liquid crystal display device - Google Patents

Abstract

PURPOSE: To prevent ripple-shaped visible defect from being generated in the vicinity of the attached part of the mounted instrument due to external shock. CONSTITUTION: 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

Liquid crystal display {LIQUID CRYSTAL DISPLAY DEVICE}

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 through an attachment portion with a mounting apparatus are suppressed.

Liquid crystal display devices are widely employed as display devices capable of high-precision and color display for notebook computers and display monitors.

In a liquid crystal display device, a pair of substrates in which parallel electrodes formed on each inner surface are formed to cross each other, and a simple matrix liquid crystal panel using a liquid crystal panel sandwiching the liquid crystal layer are used. BACKGROUND ART An active matrix liquid crystal display device using a liquid crystal panel having a switching element is known.

In the active matrix liquid crystal panel, a so-called vertical electric field system (generally, TN) is used, as the liquid crystal panel represented by the twisted nematic (TN) system uses a liquid crystal panel formed on each of a pair of upper and lower substrates. The so-called transverse electric field system (generally called an IPS system) using the liquid crystal panel in which the electrode group for pixel selection is provided only in one of a pair of upper and lower boards is called.

In the former liquid crystal panel of the TN method, the liquid crystal is aligned at an angle of 90 degrees, for example, in a pair of [two sheets consisting of a first substrate (lower substrate) and a second substrate (upper substrate)]. Two polarizing plates are arranged on the outer surface of the upper and lower substrates with cross nicol in the absorption axis direction and the absorption axis on the incident side in parallel or intersecting in the rubbing direction.

In such a TN type active matrix liquid crystal panel, when no voltage is applied, incident light becomes linearly polarized light at the incident side polarizer, and the linearly polarized light propagates according to the twist of the liquid crystal layer, and the transmission axis of the exit side polarizer is When the azimuth angles coincide, all linearly polarized light is emitted to form a white display (so-called normally open mode).

In addition, at the time of voltage application, the direction (director) of the unit vector indicating the average alignment direction of the liquid crystal molecular axes constituting the liquid crystal layer is perpendicular to the substrate surface, and since the azimuth angle of the incident-side linearly polarized light does not change, the exit side It is black because it coincides with the absorption axis of the polarizing plate (refer to "Foundation and Application of Liquid Crystal" published by the Industrial Research Council in 1991).

On the other hand, an electrode group or an electrode wiring group for pixel selection is formed only on one side of the pair of substrates, and a voltage is applied between adjacent electrodes (between the pixel electrode and the counter electrode) on the substrate, so that the liquid crystal layer is parallel to the substrate surface. In the liquid crystal panel of the IPS system which switches in the direction, the polarizing plate is arrange | positioned so that black display may be carried out when voltage is not applied (so-called normally closed mode).

The liquid crystal layer of the IPS type liquid crystal panel has a uniform (homogeneous) orientation parallel to the substrate surface in the initial state, and the director of the liquid crystal layer in a plane parallel to the substrate has a parallel or some angle with the electrode wiring direction when no voltage is applied. In addition, when the voltage is applied, the direction of the director of the liquid crystal layer shifts in the direction perpendicular to the direction of the electrode wiring according to the application of the voltage, and the direction of the director of the liquid crystal layer is inclined in the 45 ° electrode wiring direction compared to the direction of the director when no voltage is applied. When the voltage is applied, the liquid crystal layer at the time of voltage application rotates the azimuth angle of polarization by 90 degrees like the half wave plate, and the transmission axis of the emission-side deflection plate coincides with the azimuth angle of the polarization to become white display.

This IPS system liquid crystal panel has a characteristic that the change of color and contrast is small also in the viewing angle, and the wide viewing angle can be achieved (see Japanese Patent Laid-Open No. 5-505247 (Patent No. 2743293)).

In the full colorization of the liquid crystal display device using the above-mentioned various liquid crystal panels, a color filter system is mainstream. This divides a pixel corresponding to one dot of color display into three, and arranges a color filter corresponding to each of three primary colors, for example, red (R), green (G), and blue (B), in each unit pixel. By realizing it. The present invention can be applied to the above-described various liquid crystal display devices.

Although such a liquid crystal display device is mounted on an information device such as a personal computer, a mounting hole is provided on the surface of the corner portion of the liquid crystal display device and is fixed by screws or the like between the information devices. In the case where the device is mounted on a device such as a personal computer, there is no room for providing the attachment holes as described above, so that a side mount system is known in which attachment holes are provided on the side surfaces of the liquid crystal display device and fixed from the side surfaces.

It is an external view explaining an example of a liquid crystal display device, a is a front view, b is a left side view, and c is a right side view. The liquid crystal display device MDL (also referred to as a liquid crystal module) is a liquid crystal panel PNL, an optical compensation sheet composed of a backlight and a prism sheet or a diffusion sheet, a reflective sheet or a reflecting plate, and an upper frame SHD made of a metal plate and a plastic in general. The lower frame MCA of the mold is sandwiched and integrated.

The liquid crystal display device MDL shown in FIG. 13 is attached to a mounting apparatus by the side mount method mentioned above. This side mount system has a screw hole TH which reaches from the upper frame SHD to the lower frame MCA on the side of the liquid crystal display device MDL, and the display part of the mounting apparatus, for example, a personal computer (generally, a cover part), in this screw hole TH. It is attached through the screw between the screw holes in the The CT is a connector for introducing a display signal from the personal computer main body.

The screw hole of the lower frame CA is made by embedding a female screw called an inserter, and the upper frame SHD side is a through hole, and the screw is screwed into the inserter from the mounting apparatus side through this through hole.

It is a schematic diagram which shows the state which attached the liquid crystal display device to the cover of a mounting apparatus in a side mount system. In this configuration example, the reinforcement member ST, which is a substantially U-shaped, preferably metal plate, of high rigidity is provided in the cover CASE of the mounting apparatus, and the screw SC is fixed from the reinforcement member ST through the liquid crystal display device MDL. have.

The reinforcing member ST has a hinge HNG for attaching and closing the cover CASE to the personal computer main body equipped with a keyboard or the like. In this example, the reinforcing member ST is a U-shape having open side members on the left and right sides of the liquid crystal display device MDL, but it is also known that the reinforcing member ST is not only such a shape but also an individual member so as to be an independent side member on each of the left and right sides. .

FIG. 15 is a schematic sectional view near the line B-B in FIG. 14. The liquid crystal display device MDL is formed by integrating and fixing the backlight BL provided on the rear surface of the liquid crystal panel PNL in which two liquid crystal substrates SUB1 and SUB2 are sandwiched by the upper frame SHD and the lower frame MCA. The backlight BL is a light guide plate GLB made of a transparent plastic plate for propagating light from a linear lamp (generally, a cold cathode fluorescent lamp, etc. CFL), not shown, and directed in the liquid crystal panel PNL direction, and the liquid crystal panel PNL side of the light guide plate GLB. It consists of an optical compensation sheet OPS which consists of a prism sheet and a diffusion plate laminated | stacked on it, the reflection sheet RFS provided in the back surface of the light-guide plate GLB, and the reflection plate ALS which is preferably an aluminum plate.

The backlight BL is configured by placing a reflecting plate ALS and a reflecting sheet RFS in a recess ALV formed in most of the central region of the lower frame MCA, placing the light guide plate GLB on the upper portion thereof, and mounting the optical sheet OPS on the upper portion thereof. The optical sheet 0PS is sandwiched between the upper surface of the bank portion DAM formed around the lower frame MCA and the liquid crystal panel PNL through the optical compensation sheet OPS.

The inserter INS is embedded in the bank portion DAM of the lower frame MCA, and the upper frame SHD has a screw hole TH, passes through the screw SC from the screw hole of the reinforcing member ST, and is screwed into the inserter INS that is a female thread. .

In such a fixed structure, when an impact is applied from the outside, it is transmitted from the reinforcing member to the lower frame of the liquid crystal display device through the screw of the attachment portion. As a result, there exists a problem that ripple-type display defects generate | occur | produce on the display surface of a liquid crystal panel.

It is a cross-sectional schematic diagram in the vicinity of the B-B line | wire of FIG. 14 explaining the cause of the ripple-type display defect which arises in the display surface of a liquid crystal panel. The liquid crystal display device MDL is fixed to the inserter INS embedded in the lower frame MCA with the screw SC inserted through the reinforcing member ST. At this time, for example, the impact when the keyboard of the personal computer, which is a mounting apparatus, is knocked is propagated from the reinforcing member ST to the bank portion DAM of the lower frame MCA of the liquid crystal display device MDL. Since the lower frame MCA is a plastic mold and the inserter INS portion of the bank portion DAM in which the screw SC is screwed in is firmly fixed to the reinforcing member ST, this impact causes the optical portion of the bank portion DAM as shown by the arrows in the illustration. The OPS is pushed up to raise the liquid crystal panel PNL, or the light guide plate GLB is pushed up to raise the liquid crystal panel PNL.

As a result, the cell gap of the portion where the liquid crystal panel PNL is pushed up is changed by the vibration of shock, and Δnd of the portion is changed repeatedly at random, resulting in display defects formed in rippled shades on the display screen.

It is a schematic diagram explaining an example of the ripple-type display defect which arises on the display surface of a liquid crystal panel. Since the inserter INS portion of the bank portion DAM in which the screw SC of the lower frame MCA of the liquid crystal display device MDL is twisted is firmly fixed to the reinforcing member ST, Δnd due to the impact is more likely to change than this portion. Therefore, as shown in Fig. 17, a rippled display defect occurs in the inserter INS portion. In addition, such display defects are not limited to those mounted in a side-mount method, but in a structure in which the liquid crystal panel PNL changes partially due to external impact even in a method of mounting on a mounting apparatus from the surface side of the liquid crystal display device MDL. It may occur similarly. Such display defects are likely to occur in the frame structure of recent thinning.

SUMMARY OF THE INVENTION 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 a ripple-type display defect caused by, for example, a typing operation of a keyboard or other external impact is suppressed.

In order to achieve the above object, the present invention provides a structure in which a liquid crystal panel constituting a liquid crystal display device and a backlight structure are laminated so that the rise of the liquid crystal panel due to the backlight does not occur. The shape structure or the structure of the reflecting plate is improved.

Hereinafter, a representative configuration of the liquid crystal display device according to the present invention having the above structure will be described.

(1): In the liquid crystal display device which laminated | stacked the backlight on the back surface of the liquid crystal panel via the optical compensation sheet, and clamped by the upper case and the lower case,

Most of the central region of the lower case includes a bottom portion for mounting the light guide plate constituting the backlight, and includes a horizontal wall for sandwiching the optical compensation sheet between the liquid crystal panel on at least a portion of a peripheral portion of the bottom portion. And a reflecting sheet and a reflecting plate are arranged in this order on the rear surface of the light guide plate housed in the bottom part.

The horizontal wall was provided with an attachment portion for fixing the liquid crystal display device to a mounting device, and a chamfer was formed at at least a part of a vertex angle of the horizontal wall on which the attachment portion was formed to face the optical compensation sheet.

By providing the chamfer on the horizontal wall, even if the horizontal wall moves in the liquid crystal panel direction due to the impact from the outside, the liquid crystal panel is not raised by the chamfer. Therefore, the conventional display defect of the ripple type does not occur. Moreover, although it is preferable to implement the said chamfer in the whole longitudinal direction of the said horizontal wall, when the mechanical strength of the attachment part with a reinforcement member falls, you may form it avoiding the embedding part of this inserter.

(2): In the liquid crystal display device which laminated | stacked the backlight on the back surface of the liquid crystal panel via the optical compensation sheet, and clamped by the upper case and the lower case,

Most of the central region of the lower case includes a recess for accommodating the light guide plate constituting the backlight, and has a bank portion for sandwiching the optical compensation sheet between the liquid crystal panels on at least a portion of the periphery thereof. The reflective sheet and the reflecting plate are arrange | positioned in this order on the back of the light guide plate accommodated in the part,

The chamfer was formed in the side surface of the bank part with the screw hole for attaching the liquid crystal display device to the mounting apparatus, and at least a part of the vertex angle facing the optical compensation sheet of the bank part in which the screw hole was formed.

By chamfering the bank portion, even if the bank portion moves in the liquid crystal panel direction due to an impact from the outside, the liquid crystal panel is not raised by the chamfer. Therefore, the conventional display defect of the ripple type does not occur. Moreover, although it is preferable to implement the said chamfer in the whole length direction of the said bank part, when the mechanical strength of the embedding part of an inserter falls, you may form it avoiding the embedding part of this inserter.

(3): In the liquid crystal display device which laminated | stacked the backlight on the back surface of the liquid crystal panel via the optical compensation sheet, and pinched and fixed by the upper case and the lower case,

Most of the central area of the lower case includes a recess for accommodating the light guide plate constituting the backlight, and includes a bank portion for sandwiching the optical compensation sheet between the liquid crystal panels on at least a portion of the peripheral portion thereof. The reflecting sheet and the reflecting plate are arranged in this order on the back of the light guide plate to be stored in the recess,

The bank portion was provided with an attachment portion for fixing the liquid crystal display device to a mounting apparatus, and the reflective plate near the attachment portion was removed to form a gap between the rear surface of the light guide plate and the upper surface of the concave portion.

An aluminum plate or an aluminum vapor deposition plate is generally used for a reflecting plate, but a gap is formed between a lower case and a light guide plate by lacking this reflecting plate along or near the said attachment part. Therefore, even if the said bank part moves to the direction which pushes up a light guide plate by the impact from the outside, it becomes difficult to contact a light guide plate. Therefore, the conventional display defect of the ripple type does not occur.

(4): 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 sandwiched and fixed by an upper case and a lower case.

Most of the central area of the lower case includes a recess for accommodating the light guide plate constituting the backlight, and includes a bank portion for sandwiching the optical compensation sheet between the liquid crystal panels on at least a portion of the peripheral portion thereof. The reflecting sheet and the reflecting plate are arranged in this order on the back of the light guide plate to be stored in the recess,

A side surface of the bank portion was provided with a screw hole for attaching the liquid crystal display device to a mounting apparatus, and the reflecting plate near the screw hole was removed to form a gap between the rear surface of the light guide plate and the upper surface of the concave portion.

In the same manner as above, a gap is formed between the lower case and the light guide plate by missing the reflecting plate along or near the attachment portion. Therefore, even if the said bank part moves to the direction which pushes up a light guide plate by the impact from the outside, it becomes difficult to contact a light guide plate.

Therefore, the conventional display defect of the ripple type does not occur.

The effect of said (1) and the effect of (3) raise, and a ripple-shaped display defect is suppressed more effectively.

(5) 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 clamped by an upper case and a lower case.

Most of the central region of the lower case includes a recess for accommodating the light guide plate constituting the backlight, and includes a bank portion for sandwiching the optical compensation sheet between the liquid crystal panels on at least part of the peripheral portion. The reflecting sheet and the reflecting plate are arranged in this order on the back of the light guide plate to be stored in the recess,

The bank portion includes an attachment portion for fixing the liquid crystal display device to a mounting apparatus, an inclination portion is formed at least in the vicinity of the attachment portion of the recess portion, and a gap is formed between the rear surface of the light guide plate and the upper surface of the recess portion. It was.

Since a gap is formed between the lower frame and the light guide plate by the inclined portion formed at least in the vicinity of the attachment portion of the concave portion, it is difficult to contact the light guide plate even when the bank portion moves in the direction in which the light guide plate is pushed up by an impact from the outside. Therefore, the conventional display defect of the ripple type does not occur. The inclined portion may be formed all over the end of the light guide plate, or may be formed only in the vicinity of the attachment portion.

(6): A liquid crystal display device in which a backlight is laminated on a rear surface of a liquid crystal panel via an optical compensation sheet, and is clamped by an upper case and a lower case.

Most of the central area of the lower case includes a recess for accommodating the light guide plate constituting the backlight, and includes a bank portion for sandwiching the optical compensation sheet between the liquid crystal panels on at least a portion of the peripheral portion thereof. The reflecting sheet and the reflecting plate are arranged in this order on the back of the light guide plate to be stored in the recess,

A screw hole for attaching the liquid crystal display device to a mounting apparatus is provided on the side of the bank, and an inclined portion is formed at least in the vicinity of the attaching portion of the concave portion, and there is a gap between the rear surface of the light guide plate and the upper surface of the concave portion. Formed.

Similarly to the above (5), since a gap is formed between the lower frame and the light guide plate by the inclined portion formed at least in the vicinity of the screw hole portion (in the vicinity of the embedding portion of the inserter), the impact from the outside is applied. Even if the bank portion moves in the direction of pushing up the light guide plate, it is difficult to contact the light guide plate. Therefore, the conventional display defect of the ripple type does not occur.

In addition, this invention is not limited to said structure, A various change is possible without deviating from the technical idea of this invention.

Other objects and configurations of the present invention will become apparent from the following description of the embodiments.

BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a sectional view of principal parts 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 viewed from the arrow A direction in FIG. 1; FIG.

3 is an explanatory diagram of a second embodiment of a liquid crystal display device according to the present invention;

4 is an explanatory diagram of a third embodiment of a liquid crystal display device according to the present invention;

Fig. 5 is a sectional view of principal parts explaining a fourth embodiment of a liquid crystal display device according to the present invention;

6 is an essential part cross sectional view for explaining a fifth embodiment of a liquid crystal display device according to the present invention;

Fig. 7 is an external view of a notebook personal computer which is an example of an electronic apparatus mounted with a liquid crystal display device according to the present invention.

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

9 is a cross-sectional view of a portion of a thin film transistor (TFT) cut along the line 3-3 of FIG. 8;

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

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

12 is a timing diagram showing display data input from a 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.

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

14 is a schematic diagram illustrating a state in which a liquid crystal display device is attached to a cover of a mounting apparatus in a side mount manner.

FIG. 15 is a schematic sectional view near the line B-B in FIG. 14. FIG.

FIG. 16 is a schematic sectional view near the line B-B in FIG. 14 illustrating a cause of generation of a rippled display defect occurring on a display surface of a liquid crystal panel. FIG.

It is a schematic diagram explaining an example of the ripple-type display defect which arises on the display surface of a liquid crystal panel.

<Description of the code | symbol about the principal part of drawing>

ALS: Reflector

BL: Backlight

CDD: Common Driver

CRL: Display Control Unit

CVD: common voltage generator

DDR: Drain Driver

DL: Video signal line

FIL: Color Filter

GDR: Gate Driver

GL: Scanning Signal Line

LST: Level Shift Circuit

MCA: Lower Frame

MPX: Multiplexer

OPS: Optical Compensation Sheet

PNL: Liquid Crystal Panel

PWU: Power Circuit

TCON: Timing Controller

Hereinafter, with reference to the drawings of the embodiment, according to an embodiment of the present invention will be described in detail. FIG. 1 is a cross-sectional view of an essential part similar to FIG. 15 illustrating the first embodiment of the liquid crystal display according to the present invention. The configuration of the liquid crystal panel PNL and the backlight BL and the fixing structure with the reinforcing member ST of the mounting apparatus have been described with reference to FIG. 15, and thus description thereof is omitted again. In FIG. 1, INS is an inserter (female thread) embedded in the bank part of the lower frame MCA, and the liquid crystal display device MDL is screwed in and screwed the screw SC through the screw hole TH of the upper frame SHD from the reinforcement member ST of a mounting apparatus. do.

In this embodiment, the chamfer COF was implemented at the vertex angle which opposes the optical compensation sheet OPS of the bank part DAM which forms the horizontal wall of lower frame MCA. By this chamfering part COF, even if a lower frame MCA moves as demonstrated in FIG. 16, the said bank part DAM does not push up an optical compensation sheet OPS. Therefore, the cell gap of liquid crystal panel PNL does not fluctuate, and generation | occurrence | production of the ripple-shaped display defect centering on the embedding part of the inserter INS is suppressed like conventionally.

FIG. 2 is a plan view of an essential part of the lower frame constituting the liquid crystal display viewed from the arrow A direction of FIG. 1. In this embodiment, as shown in Fig. 2A, the chamfer COF is performed to avoid the vicinity of the inserter embedded in the bank portion DAM of the lower frame MCA.

2B shows the chamfer COF in the longitudinal direction of the bank portion DAM of the lower frame MCA.

FIG. 2A illustrates a case where the bank portion DAM decreases mechanical strength due to embedding of the inserter INS, and FIG. 2B illustrates a case where there is no fear that the mechanical strength decreases due to embedding of the inserter INS.

In either case, even if the bank portion DAM moves in the liquid crystal panel direction due to the impact from the outside, the bank portion DAM does not contact the liquid crystal panel (directly the optical compensation sheet OPS) by this chamfering COF. Do not raise the panel. Therefore, the conventional display defect of the ripple type does not occur.

3 is an explanatory view of a second embodiment of a liquid crystal display according to the present invention, FIG. 3A is a sectional view of an essential part, similar to that of FIG. 1, and FIG. 3B is a plan view of an essential part, illustrating a lacking state of the reflector.

In this embodiment, the lacking part CFF which lacks at least one part of the bank part DAM side of the reflecting plate ALS which comprises the backlight BL of the lower frame MCA of a liquid crystal display device is formed. In general, the reflecting plate ALS is formed by depositing aluminum on an aluminum plate or a resin sheet. The lacking part CFF of the reflecting plate ALS is formed in the part facing the inserter INS embedded in the bank part of the lower frame MCA. Moreover, what is necessary is just to select the magnitude | size of this lacking part CFF according to the mechanical strength of each structural material which comprises a liquid crystal display device.

With this configuration, even if the bank portion DAM moves in the liquid crystal panel direction due to an impact from the outside, the light guide plate GLB pushes the liquid crystal panel (directly the optical compensation sheet OPS) because there is a gap due to the lacking portion CFF of the reflecting plate RFS. There is no raising. Therefore, the conventional display defect of the ripple type does not occur.

4 is an explanatory view of a third embodiment of a liquid crystal display according to the present invention, FIG. 4A is a cross-sectional view of a main part similar to FIG. 3, and FIG. 4B is a plan view of a main part explaining a lacking state of the reflector.

The present embodiment forms a lacking part CFF that lacks at least a part of the bank DAM side of the reflecting plate ALS constituting the backlight BL of the lower frame MCA of the liquid crystal display device, and the optical part of the bank part DAM of the lower frame MCA. The chamfer OF similar to FIG. 1 is formed in at least a part of the vertex angle facing the compensation sheet OPS.

The chamfered COF formed in the bank portion DAM is not limited to the portion in which the embedding portion of the inserter INS is avoided as shown in FIG. 4B, and if the mechanical strength of the bank portion DAM is sufficiently secured, the bank portion DAM It may be formed over the entire lengthwise direction.

By setting it as the structure of a present Example, in addition to the effect of the structure of FIG. 1, the effect of the structure of FIG. 3 increases, and it can suppress generation | occurrence | production of a ripple-shaped display defect more reliably.

FIG. 5 is a cross-sectional view of an essential part similar to FIG. 1 illustrating the fourth embodiment of the liquid crystal display according to the present invention. In this embodiment, the inclined portion GV is formed on the bank portion DAM side of the bottom portion (concave portion) ALV on which the backlight BL of the lower frame MCA in FIG. 1 is mounted. By forming the inclined portion GV, the lower frame MCA does not push up the light guide plate GLB due to the impact from the outside, and the chamfered COF formed in the bank portion DAM is avoided from pushing up the liquid crystal panel PNL, and the rippled display is avoided. The occurrence of a defect can be suppressed.

Moreover, depending on the mechanical strength of the constituent material of the liquid crystal display device, it is also possible to use only the inclined portion GV formed on the bank portion DAM side of the recessed portion ALV.

6 is a cross-sectional view of an essential part illustrating a fifth embodiment of the liquid crystal display according to the present invention.

In this embodiment, the method of attaching the liquid crystal display device to the reinforcing member ST of the mounting apparatus is a screw fixing method from a plane direction different from the above embodiments.

Also in this attachment method, the impact from the outside may cause a rippled display defect of the liquid crystal panel PNL. In the present embodiment, the inclined portion GV is formed on the bank portion DAM side of the recess ALV that houses the backlight BL of the lower frame MCA, and the chamfer portion COF similar to that of FIG. 1 is also formed in the bank portion DAM.

In addition, for the liquid crystal display device having the attachment structure shown in FIG. 6, a partial CFF may be formed in the reflecting plate RFS in the side mount method described in FIGS. 3 to 5 instead of the inclined portion GV. Moreover, it becomes possible to set it as the structure which combining the chamfer part COF of the bank part DAM, the part CFF lacking in the reflecting plate RFS, and the inclination part GV of the lower frame MCA individually or in combination.

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

7 is an external view of a notebook computer, which is an example of an electronic device having a liquid crystal display device according to the present invention. The notebook personal computer is connected by a keyboard portion (main body portion) and a display portion by a hinge, and the keyboard portion includes a host computer made of a CPU or the like and a keyboard, and the liquid crystal display device MDL according to the present invention described above is provided on the display portion. It is mounted.

The drive circuit board PCB1, PCB2, PCB3, the inverter power supply IV for a backlight, etc. are mounted in the periphery of the liquid crystal panel PNL which comprises this liquid crystal display device MDL. CT is a connector for connecting to the host side, and TCON is a control circuit for generating signal processing, timing signals, and the like for displaying an image on the liquid crystal panel PNL based on the display signal input from the host side.

The liquid crystal display device according to the present invention is not limited to a portable personal computer such as a notebook type as shown in FIG. 7, but can also be used for a display device of a stationary personal computer such as a desktop monitor or other equipment. Of course.

8 is a plan view illustrating one pixel of the liquid crystal panel constituting the liquid crystal display device of the present invention and its surroundings. FIG. 9 is a cross-sectional view of a portion of a thin film transistor (TFT) cut along the line 3-3 of FIG. 8. . Fig. 8 is a block diagram of the vicinity of one pixel of a so-called TN type active matrix liquid crystal display device, each pixel comprising two adjacent scanning signal lines (gate signal lines or horizontal signal lines) GL and two adjacent image signal lines (drain signal lines). Or a vertical signal line) in a region intersecting with the DL (in a region surrounded by four signal lines).

Each pixel includes a thin film transistor TFT, a transparent pixel electrode ITO 1 and a storage capacitor Cadd. The scanning signal lines GL extend in the column direction and are arranged in plural lines in the row direction. The video signal lines DL extend in the row direction and are arranged in plural lines in the column direction.

As shown in Fig. 9, a thin film transistor TFT and a transparent pixel electrode ITO 1 are formed on the lower transparent glass substrate (lower glass substrate) SUB (1) side based on the liquid crystal LC, and the upper transparent glass substrate (upper glass substrate) is formed. ) On the SUB 2 side, the color filter FIL and the pattern BM of the black matrix for light shielding are formed.

The upper and lower transparent glass substrates SUB2, 1 have a thickness of, for example, about 0.7 mm, and film quality such as a scan signal line GL and a light shielding film (black matrix) BM formed thereon are formed. On the surface of the inner side (liquid crystal LC side) of the upper transparent glass substrate SUB 2, the light shielding film BM, the color filter FIL, and the upper alignment film ORI 2 are sequentially laminated and provided.

10 is an explanatory diagram of a configuration and a driving system of a general active matrix liquid crystal display device to which the present invention is applied. This type of liquid crystal display device includes a liquid crystal panel PNL and a data line (also called a drain signal line or a drain line) driving circuit (IC chip), that is, a drain driver DDR, a scanning line (gate signal line or gate line) around the liquid crystal panel PNL. Display control device CRL having a driving circuit (IC chip), i.e., a gate driver GDR, which is a display control means for supplying display data, clock signals, and gradation voltages for image display to these drain driver DDRs and gate driver GDRs; A power supply circuit PWU is provided.

The display data, control signal clock, display timing signal, and synchronization signal from the main body (external signal sources such as a computer, a personal computer or a television receiving circuit) are input to the display control device CRL. The display control device CRL is provided with a gradation reference voltage generator, a timing controller TCON, and the like, and converts display data from the outside into data of 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 front end of the drain driver DDR is provided as it is to the carry input of the next stage drain driver.

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

12 is a timing diagram showing display data input from a 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 the control signals (clock signal, display timing signal, synchronization signal) from the signal source and generates clock D1 (CL1), shift clock D2 (CL2) and display data as control signals to the drain driver DDR. At the same time, the frame start instruction signal FLM, the clock G (CL3), and the display data are generated as control signals to the gate driver GDR.

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

As is 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, and becomes high frequency of about 40 MHz in the XGA display element. .

As mentioned above, although this invention was demonstrated concretely based on an Example, this invention is not limited to the Example mentioned above, Of course, various changes are possible in the range which does not deviate from the summary. For example, the above embodiment has been described as applying the present invention to a TN type active matrix type liquid crystal display device, but the IPS type active matrix type liquid crystal display device, the simple matrix type and other type liquid crystal display device. The same applies to.

As described above, according to the present invention, in the structure in which the liquid crystal panel constituting the liquid crystal display device and the backlight structure are laminated, the shape structure of the lower frame is prevented from raising the liquid crystal panel due to the backlight. In addition, by improving the structure of the reflector, it is possible to provide a liquid crystal display device which suppresses the rippled display defect occurring on the screen of the liquid crystal panel in the vicinity of the mounting portion of the liquid crystal display device due to keyboard operation or other external impact. have.

Claims (14)

In the liquid crystal display device, A liquid crystal panel having a top surface and a back surface; An upper case provided on the front side and a lower frame provided on the back side; and The lower frame includes a horizontal wall portion for sandwiching the peripheral portion of the liquid crystal panel with the upper case, The horizontal wall portion has an upper holding surface opposite to the rear surface of the liquid crystal panel; and And an inclined surface facing inwardly from the holding surface. The method of claim 1, It is provided with the polarizing plate provided in the back surface side of the said liquid crystal panel, And an edge of the polarizer overlapping the inclined surface. The method of claim 1, An attachment portion provided in the horizontal wall portion, The liquid crystal display device further comprises being fixed to an external device at the attachment portion. The method of claim 1, A screw hole provided in the horizontal wall portion; The liquid crystal display device further comprises a screw is fastened to the housing portion in the screw hole. The method of claim 1, And the inclined surface is a C chamfered edge. The method of claim 1, The inclined surface is an R beveled edge. In the liquid crystal display device, Liquid crystal panels; A light guide plate disposed on a rear surface of the liquid crystal panel; A lower frame accommodating the light guide plate; The lower frame includes a bank portion surrounding the periphery of the light guide plate; And It is provided with a bottom part located below the light guide plate, And the gap between the bottom portion and the light guide plate is provided so as to be wider with respect to the other portion at the portion where the peripheral portion and the bottom portion of the light guide plate overlap. The method of claim 7, wherein The gap between the peripheral portion of the light guide plate and the bottom portion of the lower frame is formed by varying the plate thickness of the bottom portion. The method of claim 7, wherein An attachment portion provided in the bank portion, The liquid crystal display device further comprises being fixed to an external device at the attachment portion. The method of claim 7, wherein A screw hole provided in the bank section; The liquid crystal display device further comprises a screw is fastened to the housing portion in the screw hole. In the liquid crystal display device, Liquid crystal panel; and It is provided with the light guide plate arrange | positioned at the back surface of a liquid crystal panel, The light guide plate has an upper surface, a lower surface and a side surface, A lower frame accommodating the light guide plate; The lower frame includes a horizontal wall installed along the side of the light guide plate; And It has a plate portion facing the lower surface of the light guide plate, A sheet provided between the plate portion and the light guide plate; An attachment part installed on the horizontal wall, the edge of the sheet being installed along the horizontal wall; And And providing a space between the plate portion and the light guide plate by providing the edge inward from the horizontal wall near the attachment portion. The method of claim 11, A C chamfered edge is formed on the horizontal wall. The method of claim 11, An R beveled edge is formed on the horizontal wall. The method of claim 11, And the attaching portion is a screw hole.