JP3827866B2 - Liquid crystal display - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a liquid crystal display device.
[0002]
[Prior art]
In the liquid crystal display panel, the transparent substrates disposed opposite to each other with the liquid crystal interposed therebetween are used as an envelope, and the light transmittance of the liquid crystal of a large number of pixels formed in the spreading direction of the liquid crystal can be controlled.
[0003]
For this reason, usually, a backlight unit is disposed on the back surface of the liquid crystal display panel, and the liquid crystal display panel and the backlight unit are assembled into a module together with a casing surrounding them.
[0004]
Here, the casing is composed of a box-shaped resin frame and an upper frame engaged with the resin frame in order to reduce the weight of the module.
[0005]
The backlight unit is housed in the resin frame, and the liquid crystal display panel is placed on the resin frame so as to face the backlight unit, and is pressed against the resin frame by the upper frame. It has become.
[0006]
[Problems to be solved by the invention]
However, the liquid crystal display device having such a configuration has revealed the following disadvantages as the liquid crystal display panel is enlarged (for example, 18 inches in size).
[0007]
First, since the casing is a flat type having a relatively small thickness, for example, a structure that has extremely low strength against twisting when opposite rotational forces are applied to both sides on one diagonal line. It is that.
[0008]
Further, along with the increase in size of the liquid crystal display device, there has been a problem that the strength against deformation such as bending and distortion of the housing is small.
[0009]
For this reason, the liquid crystal display panel in the casing is easily twisted, and the interval between the transparent substrates constituting the envelope of the liquid crystal display panel (corresponding to the liquid crystal layer thickness) changes, which adversely affects the display. Has been pointed out.
[0010]
In addition, it is pointed out that due to the deformation of the casing, connection failure of the flexible wiring board connecting the peripheral circuit and the liquid crystal display panel occurs, or the wiring layer itself of the flexible wiring board is disconnected.
[0011]
In addition, as a backlight unit that increases with the liquid crystal display panel, it is effective to use a so-called direct type from the viewpoint of light efficiency.
[0012]
Here, the direct type backlight unit is composed of a plurality of cathode ray tubes arranged to face the liquid crystal display panel, and a reflector for guiding light from the cathode ray tube to the liquid crystal display panel side. Is.
[0013]
However, about eight cathode ray tubes of the backlight unit are required, and accordingly, a power supply circuit for supplying power to them becomes large.
[0014]
For this reason, it has been pointed out that the module including this power supply circuit must have a shape having a protruding portion in the power supply circuit portion, and a special configuration for protecting the power supply circuit is also required. Yes.
[0015]
The present invention has been made based on such circumstances, and an object thereof is to provide a liquid crystal display device having a strong structure that resists twisting.
[0016]
Another object of the present invention is to provide a liquid crystal display device in which a power supply circuit is protected.
[0017]
[Means for Solving the Problems]
Of the inventions disclosed in this application, the outline of typical ones will be briefly described as follows.
[0018]
Means 1.
In a liquid crystal display device comprising: a liquid crystal display panel; a backlight unit disposed on the back side of the liquid crystal display panel with respect to the observation side; and a casing for modularizing the liquid crystal display panel and the backlight unit.
The housing includes a side surface portion in which at least a pair of opposite sides of the outer shape viewed from the observation side extends to the back surface side.
[0019]
In the liquid crystal display device configured in this way, the casing has a substantially U-shaped cross section along a line orthogonal to the side surface portion.
[0020]
For example, this structure can greatly increase the strength against twisting when opposite rotational forces are applied to both sides on one diagonal line.
[0021]
Mean 2.
A liquid crystal display panel, a backlight unit disposed on the back side of the liquid crystal display panel with respect to the viewing side, a casing for modularizing the liquid crystal display panel and the backlight unit, and a power source for supplying power to the liquid crystal display panel A liquid crystal display device comprising a circuit,
The housing includes a side surface portion in which at least a pair of opposite sides of the outer shape viewed from the observation side extends to the back side,
The liquid crystal display device according to claim 1, wherein the power supply circuit is disposed between the side surface portion and the back surface of the housing.
[0022]
The liquid crystal display device configured as described above has an effect produced by the means 1, and the power supply circuit is configured to include a barrier (the side surface portion) in the vicinity thereof, so that external obstacles are protected. .
[0023]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of a liquid crystal display device according to the present invention will be described below with reference to the drawings.
Example 1.
[Equivalent circuit of liquid crystal display]
FIG. 1 is an equivalent circuit diagram showing an embodiment of a liquid crystal display device according to the present invention. Although this figure is a circuit diagram, it is drawn corresponding to the actual geometric arrangement.
[0024]
In this embodiment, the present invention is applied to a liquid crystal display device adopting a so-called lateral electric field method that is known to have a wide viewing angle.
[0025]
First, there is a liquid crystal display panel 1, and the liquid crystal display panel 1 includes a transparent substrate 1 </ b> A or 1 </ b> B arranged opposite to each other with liquid crystal as an envelope. In this case, one transparent substrate (lower substrate in the figure: matrix substrate 1A) is formed slightly larger than the other transparent substrate (upper substrate in the figure: color filter substrate 1B), and the lower and right sides in the figure. The peripheral edges of the are almost flush with each other.
[0026]
As a result, the periphery of the left side of the transparent substrate 1A in the drawing and the periphery of the upper side in the drawing are extended outward with respect to the other base transparent plate 1B. As will be described in detail later, this portion is a region where a gate drive circuit and a drain drive circuit are mounted.
[0027]
Pixels 2 arranged in a matrix are formed in the overlapping region of each transparent substrate 1A, 1B. The pixels 2 extend in the x direction in the drawing and are arranged in parallel in the y direction. A switching element TFT formed in a region surrounded by video signal lines 4 extending in the direction and arranged in parallel in the x direction, and driven by supply of a scanning signal from one scanning signal line 3, and the switching element And a pixel electrode to which a video signal supplied from one video signal line 4 is applied via a TFT.
[0028]
Here, as described above, each pixel 2 adopts a so-called lateral electric field method, and includes a counter electrode and an additional capacitor element in addition to the switching element TFT and the pixel electrode, as will be described in detail later. It is supposed to be.
[0029]
Each scanning signal line 3 has one end (the end on the left side in the figure) extending to the outside of the transparent substrate 1B and is connected to an output terminal of a gate drive circuit (IC) 5 mounted on the transparent substrate 1A. It is like that.
[0030]
In this case, a plurality of gate driving circuits 5 are provided, and the scanning signal lines 3 are grouped together adjacent to each other, and the grouped scanning signal lines 3 are adjacent to each adjacent gate driving circuit 5. Each is connected.
[0031]
Similarly, each video signal line 4 has one end (upper end in the figure) extending to the outside of the transparent substrate 1B and is connected to the output terminal of the drain drive circuit (IC) 6 mounted on the transparent substrate 1A. Connected.
[0032]
Also in this case, a plurality of drain drive circuits 6 are provided, and the video signal lines 4 are grouped together adjacent to each other, and each of the grouped video signal lines 4 is adjacent to each other. Are connected to each other.
[0033]
On the other hand, there is a printed circuit board 10 (control board 10) disposed in the vicinity of the liquid crystal display panel 1 on which the gate drive circuit 5 and the drain drive circuit 6 are mounted, and the printed circuit board 10 includes a power supply circuit 11 and the like. In addition, a control circuit 12 for supplying input signals to the gate drive circuit 5 and the drain drive circuit 6 is mounted.
[0034]
The signal from the control circuit 12 is supplied to the gate drive circuit 5 and the drain drive circuit 6 via flexible wiring boards (gate circuit board 15, drain circuit board 16A, drain circuit board 16B). .
[0035]
That is, on the gate drive circuit 5 side, a flexible wiring board (gate circuit board 15) having terminals connected to face the input side terminals of the gate drive circuits 5 is arranged.
[0036]
A part of the gate circuit board 15 extends to the control board 10 side, and the extension part is connected to the control board 10 via the connection part 18.
[0037]
An output signal from the control circuit 12 mounted on the control board 10 is input to each gate drive circuit 5 via the wiring layer on the control board 10, the connection portion 18, and the wiring layer on the gate circuit board 15. It has come to be.
[0038]
Also, on the drain drive circuit 6 side, drain circuit boards 16A and 16B having terminals connected to face the input side terminals of the respective drain drive circuits 6 are arranged.
[0039]
The drain circuit boards 16A and 16B are partly extended to the control board 10 side, and are connected to the control board 10 via the connection parts 19A and 19B at the extended parts.
[0040]
The output signal from the control circuit 12 mounted on the control board 10 is driven by each drain through the wiring layer on the control board 10, the connection portions 19A and 19B, and the wiring layer on the drain circuit boards 16A and 16B. The signals are input to the circuits 16A and 16B.
[0041]
The drain circuit boards 16A and 16B on the drain drive circuit 6 side are divided into two as shown in the figure. This is for preventing adverse effects due to thermal expansion due to, for example, an increase in the length of the drain circuit board in the x direction in the drawing as the liquid crystal display panel 1 is enlarged.
[0042]
The output from the control circuit 12 on the control board 10 is input to the corresponding drain drive circuit 6 via the connection part 19A of the drain circuit board 16A and the connection part 19B of the drain circuit board 16B.
[0043]
Further, a video signal is supplied to the control board 10 from the video signal source 22 through the interface board 24 by the cable 23 and is input to the control circuit 12 mounted on the control board 10.
[0044]
In this figure, the liquid crystal display panel 1, the gate circuit board 15, the drain circuit boards 16A and 16B, and the control board 10 are drawn so as to be positioned in substantially the same plane. Is bent at the gate circuit board 15 and the drain circuit boards 16A and 16B, and is positioned so as to be substantially perpendicular to the liquid crystal display panel 1.
[0045]
This is because the so-called frame area is reduced. Here, the frame means an area between the outline of the outer frame of the liquid crystal display device and the outline of the display unit. By reducing this area, the area of the display unit can be increased with respect to the outer frame. be able to.
[0046]
[LCD module]
FIG. 2 is an exploded perspective view showing an embodiment of the module of the liquid crystal display device according to the present invention.
[0047]
The liquid crystal display device shown in the figure is roughly divided into a liquid crystal display panel module 400, a backlight unit 300, a resin frame 500, a middle frame 700, an upper frame 800, etc., which are modularized.
Hereinafter, each of these members will be described sequentially.
[0048]
[LCD panel module]
The liquid crystal display panel module 400 is connected to the liquid crystal display panel 1, a gate driving IC 5 and a drain driving IC 6 each including a plurality of semiconductor ICs mounted around the liquid crystal display panel 1, and input terminals of these driving ICs. And a flexible gate circuit board 15 and drain circuit boards 16 (16A, 16B).
[0049]
That is, an output from the control board 10 described in detail later is input to the gate drive IC 5 and the drain drive IC 6 on the liquid crystal display panel 100 via the gate circuit board 15 and the drain circuit boards 16A and 16B, and the output of each of these drive ICs. Are input to the scanning signal line 2 and the video signal line 3 of the liquid crystal display panel 1.
[0050]
Here, as described above, the liquid crystal display panel 1 is composed of a large number of pixels whose display area is arranged in a matrix, and the configuration of one of these pixels is as shown in FIG. .
[0051]
In the figure, scanning signal lines 3 and counter voltage signal lines 50 extending in the x direction are formed on the main surface of the matrix substrate 1A. Then, a region surrounded by each of these signal lines 3 and 50 and a video signal line 2 extending in the y direction described later is formed as a pixel region.
[0052]
That is, in this embodiment, the counter voltage signal line 50 is formed so as to run between the scanning signal lines 3 and pixel regions are formed in the ± y directions with the counter voltage signal line 50 as a boundary. become.
[0053]
By doing in this way, the counter voltage signal line 50 arranged in parallel in the y direction can be reduced to about half of the conventional one, and the area closed by that can be shared to the pixel area side, The area of the pixel region can be increased.
[0054]
In each pixel region, the counter voltage signal line 50 is formed with counter electrodes 50A extending in the y direction integrally therewith, for example, at three true intervals. Each of these counter electrodes 50A extends close to each other without being connected to the scanning signal line 3, of which two on both sides are disposed adjacent to the video signal line 3 and the remaining one is positioned at the center. It has been.
[0055]
Further, the main surface of the transparent substrate 1A on which the scanning signal line 3, the counter voltage signal line 50, and the counter electrode 50A are formed as described above is covered with the scanning signal line 3 and the like, and is made of, for example, an insulating film made of a silicon nitride film. A film is formed. This insulating film serves as an interlayer insulating film for insulating the scanning signal line 3 and the counter voltage signal line 50 with respect to the video signal line 2 to be described later, and serves as a gate insulating film with respect to the thin film transistor TFT as a storage capacitor Cstg. Is functioning as a dielectric film.
[0056]
On the surface of this insulating film, first, a semiconductor layer 51 is formed in the formation region of the thin film transistor TFT. The semiconductor layer 51 is made of, for example, amorphous Si, and is formed on the scanning signal line 3 so as to be superposed on a portion close to the video signal line 2 described later. As a result, a part of the scanning signal line 3 also serves as the gate electrode of the thin film transistor TFT.
[0057]
A video signal line 2 extending in the y direction and arranged in parallel in the x direction is formed on the surface of the insulating film. The video signal line 2 is integrally provided with a drain electrode 2A formed so as to extend to a part of the surface of the semiconductor layer 51 constituting the thin film transistor TFT.
[0058]
Further, a pixel electrode 53 connected to the source electrode 53A of the thin film transistor TFT is formed on the surface of the insulating film in the pixel region. The pixel electrode 53 is formed by extending the center of each counter electrode 50A in the y direction. That is, one end of the pixel electrode 53 also serves as the source electrode 53A of the thin film transistor TFT and extends in the y direction as it is, and further extends in the x direction on the counter voltage signal line 50 and then extends in the y direction. It has a letter shape.
[0059]
Here, a portion of the pixel electrode 53 that overlaps the counter voltage signal line 50 forms a storage capacitor Cstg that uses the insulating film as a dielectric film between the counter voltage signal line 50 and the portion. For example, when the thin film transistor TFT is turned off, the storage capacitor Cstg has an effect of storing video information in the pixel electrode 53 for a long time.
[0060]
The surface of the semiconductor layer 51 corresponding to the interface between the drain electrode 2A and the source electrode 53A of the thin film transistor TFT described above is doped with phosphorus (P) to form a high concentration layer. Contact is being made. In this case, the high-concentration layer is formed over the entire surface of the semiconductor layer 51, and after forming each electrode, the high-concentration layer other than the electrode formation region is etched using the electrode as a mask. It can be set as said structure.
[0061]
A protective film made of, for example, a silicon nitride film is formed on the upper surface of the insulating film on which the thin film transistor TFT, the video signal line 2, the pixel electrode 53, and the storage capacitor Cstg are formed. An alignment film is formed to constitute a so-called lower substrate of the liquid crystal display panel 1.
[0062]
Although not shown, a black matrix (reference numeral 54 in FIG. 3) has an opening in a portion corresponding to each pixel region in a portion on the liquid crystal side of a transparent substrate (color filter substrate) 1B serving as a so-called upper substrate. Corresponding to) is formed.
[0063]
Further, a color filter is formed covering an opening formed in a portion corresponding to the pixel region of the black matrix 54. The color filter has a color different from that in the pixel region adjacent in the x direction, and has a boundary on the black matrix 54.
[0064]
In addition, a flat film made of a resin film or the like is formed on the surface on which the black matrix and the color filter are formed, and an alignment film is formed on the surface of the flat film.
[0065]
〔Backlight〕
A backlight unit 300 is disposed on the back surface of the liquid crystal display panel module 400.
[0066]
The backlight unit 300 is a so-called direct type, and includes a plurality of (eight in the figure) cold cathode ray tubes 35 extending in the x direction and arranged in parallel in the y direction. The reflector 36 is configured to irradiate the light from the cold cathode ray tube 35 to the liquid crystal display panel module 400 side.
[0067]
The reflector 36 is formed in a wave shape, for example, in the juxtaposed direction (y direction) of the cold cathode ray tubes 35. In other words, each cold cathode ray tube 35 has an arcuate concave portion where the cold cathode ray tube 35 is disposed, and has a shape having a sharp convex portion between the cold cathode ray tubes, and all of the light from each cold cathode ray tube is converted into the liquid crystal. The shape is efficient for irradiating the display panel module side.
[0068]
(Resin frame)
The resin frame 500 constitutes a part of the outer frame of the modularized liquid crystal display device, and accommodates the backlight unit 300.
[0069]
Here, the resin frame 500 has a box shape having a bottom surface and a side surface, and an upper end surface of the side surface can mount a diffusion plate (not shown) disposed so as to cover the backlight unit 300. ing.
[0070]
This diffusion plate has a function of diffusing light from each cold cathode ray tube 35 of the backlight unit 300, and thereby, the liquid crystal display panel module 400 side can be irradiated with uniform light with no unevenness of brightness. It can be done.
[0071]
In this case, the resin frame 500 is formed with a relatively small thickness. This is because the reduction in mechanical strength can be reinforced by the middle frame 700 described later.
[0072]
A DC / AC inverter board 40 that is one of the power supply circuits 11 is attached to the back surface of the resin frame 500.
[0073]
The DC / AC inverter board 40 constitutes a part of a power supply device for supplying power to each cold cathode ray tube 35 of the backlight unit 300, and the connection from the DC / AC inverter board 40 is connected to each cold cathode ray tube 35. It is designed to be connected to the terminals at both ends.
[0074]
FIG. 4 is a view of the resin frame 500 as seen from the back surface thereof, that is, the surface opposite to the side on which the backlight unit 300 is disposed.
[0075]
As is apparent from the figure, the resin frame 500 is formed with protrusions 500A in which the sides parallel to the x direction protrude along the sides.
[0076]
That is, the resin frame 500 is provided with a side surface portion 500B in which a pair of sides (sides parallel to the x direction) with respect to the outer shape viewed from the observation side of the liquid crystal display device extend to the back side. Is formed.
[0077]
The reason for this configuration is that the resin frame 500 also has an effect of imparting strength against twisting due to the reverse rotational force on the diagonal line. This is because the strength of the housing constituted by the combination of the above is made sufficient.
[0078]
Further, the height of the side surface portion 500B of the resin frame 500 is formed to be higher than the height of the DC / AC inverter board 40, as will be apparent from the following description, and thus becomes relatively large. However, as described above, the control board 10 is disposed close to the side surface portion 500B so as to face the side surface portion 500B (actually, via the middle frame 700).
[0079]
For this reason, there is an effect that the control substrate 10 having a complicated circuit configuration can be configured as a large one.
[0080]
In addition, since the control frame 10 in this case has the middle frame 700 between the control substrate 10 and the liquid crystal display panel module 400 side, an effect of having a shielding function against electromagnetic waves is also achieved.
[0081]
In this embodiment, the protrusion 500A is provided on each side parallel to the x direction. However, the present invention is not limited to this, and the same may be provided on each side parallel to the y direction. It goes without saying that the effects of
[0082]
[DC / AC inverter board]
FIG. 5 is a view showing the DC / AC inverter board 40 disposed on the back surface of the resin frame 500.
[0083]
The DC / AC inverter board 40 is equipped with transformers 71 corresponding to the number of cold cathode ray tubes 35 of the backlight unit 300 (eight in this embodiment). Are arranged so as to substantially overlap one end side (high pressure side).
[0084]
This is because when power is supplied to each cold cathode ray tube 35, the length of the wiring can be made as short as possible.
[0085]
The DC / AC inverter board 40 is arranged via a shield plate 72 made of metal attached to the back surface of the resin frame 500, but a part of the shield plate 72 (DC / AC An opening 72A is provided in a substantially mounting portion of the inverter board 40). This is to avoid the generation of eddy current in the shield plate 72 by the transformer 71.
[0086]
And the DC / AC inverter board | substrate 40 attached in this way is the height of the grade which does not protrude from the projection part 500B of the said resin frame 500 also including the mounted component.
[0087]
In other words, the protrusion 500B of the resin frame 500 is set sufficiently high so that the DC / AC inverter board 40 including the mounted components does not protrude.
[0088]
[Medium frame]
An intermediate frame 700 is disposed between the liquid crystal display panel module 400 and the diffusion plate.
[0089]
The middle frame 700 is formed of a relatively thin metal plate having an opening 42 formed in a portion corresponding to the display area of the liquid crystal display panel module 400.
[0090]
The middle frame 700 has a function of pressing the diffusion plate against the resin frame 500 and a function of placing the liquid crystal display panel module 400.
[0091]
Therefore, a spacer 44 for positioning the liquid crystal display panel 100 is attached to a part of the upper surface of the middle frame 700 on which the liquid crystal display panel module 400 is placed. As a result, the liquid crystal display panel 100 can be accurately positioned with respect to the middle frame 700.
[0092]
The inner frame 700 has a shape in which the side surface 46 is integrally formed. In other words, the inner frame 700 has a shape in which the opening 42 is formed on the bottom surface of a substantially metal plate.
[0093]
The intermediate frame 700 having such a shape is fitted to the resin frame 500 with the diffusion plate 600 disposed therebetween. In other words, the middle frame 700 is stacked on the resin frame 500 so that the inner wall of the side surface 46 faces the outer wall of the side surface of the resin frame 500.
[0094]
The middle frame 700 of the metal plate configured in this way constitutes one frame (housing) together with the resin frame 500, and the mechanical frame without increasing the thickness of the resin frame 500. Strength can be improved.
[0095]
That is, each of the middle frame 700 and the resin frame 500 is improved in mechanical strength by being fitted as described above even if the mechanical strength is not sufficient. It has strength against twisting around.
[0096]
In addition, the protrusion 500A formed on the resin frame 500 also increases the strength against twisting around the diagonal line of the box.
[0097]
For this reason, there exists an effect which can ensure sufficient intensity | strength, without enlarging what is called a frame in the module of a liquid crystal display device.
[0098]
Further, the middle frame 700 itself has an effect that the mechanical strength is increased and the handling in the previous stage of the assembly of the module is facilitated as compared with a substantially planar one having no side surface.
[0099]
In this embodiment, the control board 10 and the DC / DC converter board 11 are arranged to face each other on a part of the side surface 46 of the middle frame 700. In other words, the frame is arranged perpendicular to the liquid crystal display panel module 400, thereby reducing the frame.
[0100]
In this case, the control board 10 is connected to the flexible gate circuit board 15 and the drain circuit boards 16A and 16B attached to the liquid crystal display panel module 400 via the connecting portions 18, 19A and 19B, respectively. The above-described arrangement is achieved by bending.
[0101]
As described above, the side surface 46 of the middle frame 700 can avoid the influence of the electromagnetic wave generated from the control board 10 on other members by doing so.
[0102]
In the above-described embodiment, the box shape is described as the shape of the middle frame 700. However, it is not necessary to be a complete box shape, and at least one side surface may be formed.
[0103]
This is because such an intermediate frame 700 is not planar, but has a bent portion, and thereby has a structure in which mechanical strength is improved.
[0104]
[Upper frame]
The upper frame 800 has a function of pressing the liquid crystal display panel module 400, the middle frame 700, and the diffusion plate toward the resin frame 500, and constitutes the outer frame of the module of the liquid crystal display device together with the resin frame 500. It is like that.
[0105]
The upper frame 500 is formed with an opening (display window) 48 in a portion corresponding to the display area of the liquid crystal display panel module 400 on a metal plate having a substantially box shape, and is locked to the resin frame 500, for example. It can be attached.
[0106]
The upper frame 800 also has a function as a shield material.
[0107]
[Assembly of the above parts]
FIG. 6 is a view showing the assembly of the components shown in FIG. 2. The center is a plan view seen from the upper frame 800 side, and the left, right, upper and lower views are side views seen from that direction.
[0108]
Here, from the left and right drawings in the figure, the DC / AC inverter board 40 arranged on the back surface of the resin frame 500 is arranged without protruding from the side surface of the upper frame 800 (in other words, in an unobservable state). It turns out that.
[0109]
Further, from the left and right drawings in the figure, it is found that the resin frame 500 has a U-shaped cross section due to the protrusion 500A.
[0110]
As described above, the resin frame 500 having such a shape has a large resistance to twisting due to the reverse rotational force on the diagonal.
[0111]
[Configuration in which cooling means is attached to the assembly]
FIG. 7 is a perspective view showing a configuration in which a cooling unit and a power supply circuit connected to the DC / AC inverter board 40 are attached to the assembly shown in FIG.
[0112]
In the figure, a shield material 100 is disposed so as to cover the back side of a resin frame 500, and a pair of cooling fans 102A and 102B are attached to the lower side of the shield material 100.
[0113]
Of the pair of cooling fans 102A and 102B, one cooling fan 102A is disposed so as to overlap the lower part of the DC / AC inverter board 40, and a portion of the shield material 100 to which the cooling fan is attached serves as an air flow path. Are provided.
[0114]
As a result, the air flowing in by the cooling fan 102A cools the lower part of the DC / AC inverter board 40, and the air slightly warmed by the cooling rises to reach the upper part of the DC / AC inverter board 40. Can be cooled.
[0115]
For this reason, a hole 104 through which the air is released is formed in the upper part of the shield material 100, and the air is sufficiently circulated.
[0116]
In FIG. 7, the hole 104 is formed in the upper part of the frame body in parallel in the x direction. However, it goes without saying that at least the electrode portions of the cold cathode ray tube 35 may be formed so as to substantially overlap each other, and the diameter of the hole may be increased.
[0117]
The cooling in this case can cool not only the DC / AC inverter board 40 but also the cold cathode ray tube 35 disposed via the resin frame 500 at the same time.
[0118]
Here, it is known that the cold cathode ray tube 35 is not heated all over, but is heated particularly at the electrode portions at both ends thereof.
[0119]
For this reason, since the one cooling fan 102A is disposed so as to overlap with one end portion of the cold cathode ray tube 35, one end portion of each cold cathode ray tube 35 can be sufficiently cooled.
[0120]
For this reason, of the pair of cooling fans 102A and 102B, the other cooling fan 102A is arranged so as to overlap the other end of the cold cathode ray tube 35.
[0121]
For these reasons, each cold cathode ray tube 35 is sufficiently cooled by the cooling fans 10A and 102B at both ends (electrode portions) thereof, so that it is not heated.
[0122]
This brings about an effect that the liquid crystal in the liquid crystal display panel 1 does not cause the characteristic deterioration due to the heating, so that the quality can be ensured for a long time.
[0123]
Further, since a relatively large space is formed between the pair of cooling fans 102A and 102B, the space can be effectively used by arranging the power supply circuit 106 connected to the DC / AC inverter board 40. It becomes like this.
[0124]
The shield member 100 is configured to have a side surface 100A that is bent so as to come into contact with the side surface of the assembly in order to further reinforce the twisting of the assembly shown in FIG. .
[0125]
FIG. 8 is a configuration diagram viewed from the display surface side, and it is clear that the side surface 100A of the shield material 100 is bent so as to abut against the four side surfaces of the assembly.
[0126]
The shield material 100 has a configuration in which a power supply circuit 106 is mounted on the upper surface thereof. However, it goes without saying that the power supply circuit 106 may be mounted on the shield plate 72 shown in FIG.
[0127]
In this case, the shielding material 100 can shield the power supply circuit 106 in a shape in which the corresponding region is swollen, and can prevent propagation of electromagnetic waves to the outside of the liquid crystal display device. It becomes like this.
[0128]
7 and 8, a support base is attached to the lower side thereof, and the liquid crystal display device described in this embodiment can be used as a so-called liquid crystal display monitor.
[0129]
[Assembly with the cooling means attached]
FIG. 9 is a diagram showing the configuration shown in FIG. 7 (and FIG. 8), in which the center is a plan view seen from the upper frame 800 side, and each of the left, right, top and bottom figures shows a side view seen from that direction. .
[0130]
As is clear from this figure, even when all the necessary parts for the liquid crystal display monitor are attached, the thickness can be reduced, and the most important advantages of the liquid crystal display monitor can be configured without damaging it. Become.
[0131]
[Other Examples]
In the above-described embodiments, a liquid crystal display device called a so-called lateral electric field method has been described.
[0132]
However, it goes without saying that the present invention can also be applied to other types of liquid crystal display devices such as a vertical electric field method.
[0133]
This is because there is only a main difference in the structure of the pixel that controls the light transmittance of the liquid crystal, and the rest of the configuration other than that is almost the same.
[0134]
【The invention's effect】
As is apparent from the above description, according to the liquid crystal display device of the present invention, a structure having high strength against twisting can be provided.
Further, the power supply circuit can be protected.
[Brief description of the drawings]
FIG. 1 is an equivalent circuit diagram showing an embodiment of a liquid crystal display device according to the present invention.
FIG. 2 is an exploded perspective view showing an embodiment of a liquid crystal display device according to the present invention.
FIG. 3 is a plan view showing an embodiment of a pixel configuration of a liquid crystal display device according to the present invention.
FIG. 4 is a (back) perspective view showing an embodiment of a resin frame used in the liquid crystal display device according to the present invention.
FIG. 5 is a plan view showing one embodiment of the arrangement of DC / AC inverter substrates used in the liquid crystal display device according to the present invention.
6 is a diagram showing an assembly of each component shown in FIG. 2, in which the center is a plan view seen from the observation side, and each of the left, right, upper and lower views shows a side view seen from that direction.
FIG. 7 is a perspective view showing an embodiment of the arrangement of cooling fans used in the liquid crystal display device according to the present invention.
8 is a perspective view showing a configuration when the configuration shown in FIG. 7 is viewed from the opposite side. FIG.
9 is a diagram showing the configuration shown in FIG. 7 (and FIG. 8), in which the center is a plan view seen from the observation side, and each of the left, right, upper and lower figures shows a side view seen from that direction.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Liquid crystal display panel, 10 ... Control board, 40 ... DC / AC inverter board, 71 ... Transformer, 72 ... Shield plate, 300 ... Backlight unit, 500 ... Resin frame, 500A ... Projection part, 500B ... Side part, 102A, 102B ... Cooling fan, 106 ... Power supply circuit. 400 ... Liquid crystal display panel module, 700 ... Middle frame, 800 ... Upper frame.

Claims (6)

In a liquid crystal display device comprising a liquid crystal display panel, a backlight unit disposed on the back side of the liquid crystal display panel with respect to the observation side, and a casing for modularizing the liquid crystal display panel and the backlight unit,
The housing has a bottom shape and a side surface to form a box shape,
The backlight is housed between the bottom surface of the housing and the liquid crystal display panel,
The side surface extends to the back side from the bottom surface , and includes a protruding portion formed along the side of the housing .
The liquid crystal display device wherein the protrusions, wherein Rukoto that have a continuous surface from the side. In a liquid crystal display device comprising: a liquid crystal display panel; a backlight unit disposed on the back side of the liquid crystal display panel with respect to the viewing side; a resin frame housing the backlight unit; and a power supply circuit.
The resin frame has a box shape having a bottom surface and a side surface,
The backlight is housed between the bottom surface of the resin frame and the liquid crystal display panel,
The side surface extends to the back side from the bottom surface , and includes a protruding portion formed along the side of the resin frame ,
The projections have a continuous surface from the side Rutotomoni,
The liquid crystal display device, wherein the power supply circuit is disposed on the bottom surface of the resin frame and between the protrusions. The liquid crystal display panel includes a video signal driving circuit mounted on one side thereof, and a control circuit connected to the video signal driving circuit,
The liquid crystal display device according to claim 1, wherein the control circuit is housed in a side surface of the housing or the resin frame.   The backlight unit includes a plurality of cathode ray tubes disposed to face the liquid crystal display panel, and a reflector that guides light from the cathode ray tubes to the liquid crystal display panel side. 3. The liquid crystal display device according to any one of 1 and 2.   3. The liquid crystal display device according to claim 2, wherein the height of the protrusion is configured to be higher than the thickness of the power supply circuit disposed on the bottom surface of the resin frame.   6. The liquid crystal display device according to claim 2, wherein the power supply circuit comprises an inverter circuit.

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