JP2003005157A - Liquid crystal display device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a liquid crystal display device preventing dust from entering into even when there are a worked relief part and a gap caused by press work in parts constituting the liquid crystal display device or a structural gap generated on a place to lock a reflection sheet. SOLUTION: A spacer 6 formed with a platy elastic member is embedded in a space provided in a structure of a peripheral frame 4. Also a dust entering preventing tape 3 is stuck to and covers a part with the worked relief part 2b and the gap 2d existing in the vicinity of a drawing part 2a on a sheet metal member such as a rear side cover 2.

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 that displays characters and images, and more particularly to a liquid crystal display device that prevents dust from entering.

[0002]

2. Description of the Related Art Liquid crystal display devices are smaller and lighter in weight than cathode ray tubes (cathode ray tubes) and consume less power. The technology has been progressing, and a wide variety of liquid crystal display devices have been commercialized and spread. However, when dust enters from the outside into the illumination unit that emits light from the back side of the liquid crystal display module, even small dust appears on the display screen due to illumination, so it is necessary to have a structure that does not allow the dust to enter from the outside.

A conventional liquid crystal display device will be described below with reference to FIG.
This will be described with reference to FIGS. 7 and 8. FIG. 6 is an exploded perspective view of a conventional liquid crystal display device, FIG. 7 is a sectional view of the conventional liquid crystal display device, and FIG. 8 is an exploded rear view of the conventional liquid crystal display device. Reference numeral 1 denotes the entire liquid crystal display device for displaying characters and images, in which a pair of transparent substrates on which display electrodes are laid face each other at appropriate intervals, a liquid crystal material is injected into the intervals, and the periphery of the transparent substrate is sealed with a sealing material. A liquid crystal panel that is configured by sealing with, a plurality of drive circuits that are arranged around the liquid crystal panel for displaying the liquid crystal panel, a circuit board on which the drive circuits are mounted, and the liquid crystal module And a lighting unit and the like arranged behind the lamp and transmitting the light emitted from the lamp to the entire rear surface of the liquid crystal display module.

Reference numeral 2 denotes a back cover, which is a component forming the back surface of the liquid crystal display device 1, and is made of, for example, sheet metal. 2a
Is a squeezed portion provided on the left and right sides of the back cover 2, and when there is a locally high portion inside the back cover 2, by partially squeezing the back cover 2 to raise the surface height,
A locally high part can be formed. Reference numeral 2b denotes a crushing portion which is necessary when pressing the squeezed portion 2a, and 2c is a bent portion. 2d squeezing part 2
It is a gap formed on the left and right of the squeezing portion 2a in order to squeeze a into a trapezoid.

Reference numeral 4 denotes an outer peripheral frame which holds the liquid crystal display module and constitutes the main body of the liquid crystal display device, and is made of, for example, resin injection molding. 4a is a peripheral frame 4
Side surface portions 4b provided on the left and right sides of the outer peripheral frame 4 have concave section portions 4c on the inner side of the left and right side surface portions 4a of the outer circumferential frame 4, and side surface portions 4a sandwich the concave section portion 4b of the outer peripheral frame 4 on both sides. And the side surface portion 4a, which is a protruding gate portion that is connected in a gate-holding shape on a surface higher than the concave portion 4b in cross section.
Is part of. 4d is a space formed by the upper surface of the concave section 4a and the lower surface of the protruding gate section 4c, and has a slit shape when viewed from the front.

Reference numeral 5 is a reflection sheet for reflecting the light emitted from the lamp on the entire back surface of the liquid crystal display module 1, and is made of, for example, a white polyester sheet. Reference numerals 5a are locking projections provided on the left and right of the reflection sheet 5a for positioning. Reference numeral 7 denotes a light guide plate for transmitting the light emitted from the lamp to the entire back surface of the liquid crystal display module 1, which is a part of the illumination unit, and is made of, for example, a transparent acrylic resin. Reference numeral 7 a denotes a concave positioning portion provided on the left and right for positioning the light guide plate 7 inside the outer peripheral frame 4.

The conventional liquid crystal display device configured as described above is assembled as follows. First, the liquid crystal display module is attached to the outer peripheral frame 4. Next, an illumination unit section that illuminates the liquid crystal display module from the back side is configured. In the illumination unit portion, the light guide plate 7 and the reflection sheet 5 are inserted in this order in the portion surrounded by the side surface portions 4a of the outer peripheral frame 4 provided on the left and right of the outer peripheral frame 4. Here, the light guide plate 7 and the reflection sheet 5 are surrounded on the left and right side surfaces by the side surface portion 4 a of the outer peripheral frame 4. Further, the light guide plate 7 has concave positioning portions 7a on the left and right, and the light guiding plate 7b has a concave section 4b provided inside from the side surface portion 4a of the outer peripheral frame 4 in the left and right positioning portions 7a. 7 is arranged on the outer peripheral frame 4. Since the concave section 4b of the outer peripheral frame 4 is inserted into the concave positioning portion 7a of the light guide plate 7, the light guide plate 7 in the outer peripheral frame 2 can be positioned both vertically and horizontally.

Next, the reflection sheet 5 is placed on the light guide plate 7. Here, the positioning portion 7 of the light guide plate 7 is also provided on the reflection sheet 5.
When the positioning portion having the same size as a is provided, the reflection sheet 5 is, for example, a polyester sheet and has a small thickness.
If the side surface portion 4a of the outer peripheral frame 4 is not sufficiently higher than the surface of the light guide plate 7, the reflection sheet 5 will move over the side surface portion 4a of the outer peripheral frame 4 and shift when the liquid crystal display device receives a shock or vibration. . Therefore, the reflection sheet 5 is provided with a locking projection 5a, and the outer peripheral frame 4 is provided with a slit hole 4d so that the locking projection 5a can be positioned on a surface higher than the sectional recessed portion 4b of the outer peripheral frame 4. Slit hole 4
d is a concave section 4 when the outer peripheral frame 4 is injection-molded.
b, and a protruding gate portion 4c having a shape in which the side surface portion 4a is connected to the side surface portion 4a and the surface higher than the concave portion 4b in cross section in a gate-holding shape with the concave portion 4b in cross section sandwiched therebetween. As a result, a space and a slit hole 4d are formed between the lower surface of the protruding gate portion 4c and the upper surface of the concave portion 4b in cross section. The reflection sheet 5 can be positioned by inserting the locking projection 5a of the reflection sheet 5 into the slit hole 4d in this space.

Next, the back cover 2 is attached to the outer peripheral frame 4 to form an illumination unit section. Here, in order to position the reflection sheet 5 by the locking projections 5a of the reflection sheet 5, a projection gate portion 4c is provided on the outer peripheral frame 4, but since this is higher than the side surface portion 4a, the back cover 2 is In order to cover the protruding gate portion 4c, a squeezing process is partially performed to provide a squeezing process part 2a. By providing the trapezoidal squeezed portion 2a by pressing, the back cover 2 is provided with a squeezed portion 2b and a gap 2d by pressing. The bent portion 2c is aligned with the side surface portion 4a, and the squeezed portion 2a is placed on the protruding gate 4c.
Attach the back cover 2. The illumination unit is configured as described above and arranged in the liquid crystal display device 1.

[0010]

However, in the above-mentioned conventional structure, the light guide plate 7 and the light guide plate 7 are reflected through the slit holes 4d formed in the outer peripheral frame 4 for allowing the locking projections 5a of the reflection sheet 5 to pass therethrough. There is a problem that dust enters between the sheet 5 and the sheet 5. As for the invasion of the dust, in addition to the dust floating in the outside air, the dust accumulated in the concave section 4b having a concave section inside the slit hole 4d enters. Since the outer peripheral frame 4 is formed of resin, static electricity is likely to be generated, and therefore dust is likely to be accumulated in the recessed shape (the corner of the box shape). In particular, dust is likely to be accumulated on a portion having a complicated shape such as the slit hole 4d or the concave portion 4b in cross section, and it is difficult to remove the dust. On the other hand, since static electricity is generated between the light guide plate 7 and the reflection sheet 5, dust in the vicinity is easily absorbed and invaded. Therefore, in addition to the dust floating in the outside air, the slit hole 4d of the outer peripheral frame 4 and the concave portion 4b in cross section are provided.
The dust that has accumulated on the outer peripheral frame 4 enters between the light guide plate 7 and the reflection sheet 5 through the slit holes 4d of the outer peripheral frame 4.

On the other hand, since there is a bite-processed part 2b and a gap 2d on the left and right of the squeezed-processed part 2a of the back cover 2, there is also a problem that external dust enters from this part. Such a problem of dust invasion is a problem relating to all contact points between the outer peripheral frame 4 and the back cover 2, but in particular, invasion of dust from the above-mentioned sites is a serious problem.

Therefore, an object of the present invention is to solve the above-mentioned problems of the prior art, and to fix a reflection sheet by forming a gap or a gap in a component of a liquid crystal display device by press working. An object of the present invention is to provide a liquid crystal display device that can prevent dust from entering even when a structural gap is generated at a location.

[0013]

In order to achieve this object, a liquid crystal display device according to claim 1 of the present invention has at least a light guide plate which constitutes an illumination unit, and a reflection sheet which is arranged on the back surface side of the light guide plate. And a peripheral frame that holds these from the outer peripheral side, a back cover that holds these from the back side, and a slit hole formed to allow the locking projection of the reflection sheet to pass through the side surface of the outer peripheral frame. In a liquid crystal display device having a concave cross-section formed inside the hole, a spacer for preventing dust intrusion is attached inside the concave cross-section of the outer peripheral frame, and the end face of the attached spacer is the light guide plate end face. Characterized by extending to the outside. The spacer may be attached with a double-sided tape or the like, or may be fitted inside the recessed section.

According to the present invention, since the spacer for preventing dust from entering is attached to the inside of the recessed section of the outer peripheral frame, dust is prevented from accumulating in the recessed section of the outer peripheral frame. Further, since the end surface of the spacer extends to the outside of the end surface of the light guide plate, even if dust adheres to the end surface of the spacer, since it is separated from the end surface of the light guide plate, it is less susceptible to static electricity due to the light guide plate and the reflection sheet. Therefore, it is possible to prevent the dust accumulated in the concave portion in section from entering between the light guide plate and the reflection sheet through the slit holes of the outer peripheral frame as in the conventional case.

A liquid crystal display device according to claim 2 of the present invention is
In a liquid crystal display device including at least a light guide plate that constitutes an illumination unit, a reflection sheet that is arranged on the back side of the light guide plate, an outer peripheral frame that holds these from the outer peripheral side, and a back cover that holds these from the back side. It is characterized in that a tape for preventing dust intrusion is attached so as to cover a gap generated at a contact portion between the outer peripheral frame and the back cover.

According to the present invention, since the dust intrusion prevention tape is attached to the gap formed at the contact portion between the outer peripheral frame and the back cover, the gap between the contact portion between the outer peripheral frame and the back cover is formed. This will prevent dust from entering.

A liquid crystal display device according to claim 3 of the present invention comprises:
On the premise of the invention as set forth in claim 2, a locking projection is formed on the reflection sheet, and a gap formed at a contact portion between the outer peripheral frame and the back cover has a locking projection of the reflection sheet on a side surface portion of the outer peripheral frame. It is a gap formed between the slit hole formed for passing through and the left and right of the squeezed portion provided on the back cover to cover the slit hole. It is characterized by having left and right side portions that cover at least a gap formed on the left and right of the processed portion.

According to the present invention, since the tape for preventing dust intrusion covers at least the gap formed on the left and right of the squeezed portion of the back cover, dust from the gap formed on the left and right of the squeezed portion provided on the back cover is prevented. It will prevent intrusion.

The liquid crystal display device according to claim 4 of the present invention is
At least the light guide plate that constitutes the lighting unit, the reflection sheet that is arranged on the back surface side of the light guide plate, the outer peripheral frame that holds these from the outer peripheral side, and the back cover that holds these from the rear surface side are provided. Has a slit hole formed to allow the locking projection of the reflection sheet to pass therethrough, and a concave section having a concave section inside the slit hole, and is provided on the back cover corresponding to these positions. In a liquid crystal display device that has a gap that can be formed on the left and right of the squeezed portion, a spacer for preventing dust intrusion is attached inside the concave portion of the outer peripheral frame, and the end surface of the attached spacer extends beyond the end surface of the light guide plate. On the other hand, a dust intrusion prevention tape having left and right side portions covering at least the gap formed on the left and right of the squeezed portion of the back cover is attached. And wherein the door.

According to the present invention, since the dust invasion preventing spacer is attached to the inside of the concave section of the outer frame, the dust is prevented from accumulating in the concave section of the outer frame. Further, since the end surface of the spacer extends to the outside of the end surface of the light guide plate, even if dust adheres to the end surface of the spacer, since it is separated from the end surface of the light guide plate, it is less susceptible to static electricity due to the light guide plate and the reflection sheet. Therefore, it is possible to prevent the dust accumulated in the concave portion in section from entering between the light guide plate and the reflection sheet through the slit holes of the outer peripheral frame as in the conventional case.
Further, since the dust intrusion prevention tape covers at least the gap formed on the left and right of the squeezed portion of the back cover, it prevents dust from entering through the gap formed on the left and right of the squeezed portion provided on the back cover. . Therefore,
Make sure that there are gaps or gaps formed by press working at the contact points between the outer frame and the back cover that make up the liquid crystal display device, or that there are structural gaps at the points for locking the reflection sheet. Even in such a case, it is possible to prevent dust from entering.

A liquid crystal display device according to claim 5 of the present invention is
On the premise of the invention according to claim 1 or 4, the spacer for preventing dust intrusion is a plate-shaped elastic member having a size that fits inside the center of the recessed section of the outer peripheral frame. To do. The plate-shaped elastic member is, for example, urethane rubber or the like.

According to the present invention, when the dust intrusion preventing spacer is mounted inside the concave section of the outer frame, the dust intruding spacer is fitted into the concave section of the outer frame while elastically deforming. It can be attached without using double-sided tape.
Moreover, when a rubber material such as urethane rubber is used as the spacer material, static electricity is less likely to be generated, so that dust is less likely to be adsorbed to the spacer portion.

[0023]

BEST MODE FOR CARRYING OUT THE INVENTION An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a rear perspective view of a liquid crystal display device according to an embodiment of the present invention, FIG. 2 is a rear view of a liquid crystal display device according to the embodiment of the present invention, and FIG. 3 is a liquid crystal display according to the embodiment of the present invention. FIG. 4 is a sectional view of the device, FIG. 4 is an exploded perspective view of the liquid crystal display device according to the embodiment of the present invention, and FIG. 5 is an exploded rear view of the liquid crystal display device according to the embodiment of the present invention. Reference numeral 1 denotes an entire liquid crystal display device 1 for displaying characters and images, which includes a liquid crystal module and a lighting unit.
The liquid crystal module is configured by facing a pair of transparent substrates on which display electrodes are laid at appropriate intervals, injecting a liquid crystal material into the intervals, and sealing the periphery of the transparent substrate with a sealing material S. The panel includes a panel, a plurality of driving circuits arranged around the liquid crystal panel for displaying the liquid crystal panel, and a circuit board on which the driving circuit is mounted. The lighting unit is disposed behind the liquid crystal module and transmits the light emitted from the lamp to the entire back surface of the liquid crystal module.

Reference numeral 2 denotes a back cover, which is a component that constitutes the back surface of the liquid crystal display device 1, and is made of, for example, sheet metal. 2a
Is a squeezed portion provided on the left and right sides of the back cover 2, and when there is a locally high portion inside the back cover 2, by partially squeezing the back cover 2 to raise the surface height,
Can cover high parts inside. Reference numeral 2b denotes a crushing portion required for pressing the squeezed portion 2a, and reference numeral 2c denotes a bent portion. 2d is a squeezed portion 2a
This is a gap that can be formed on the left and right sides of the squeezing portion 2a for trapezoidal processing. Reference numeral 3 is a dust intrusion prevention tape, and 3a is a recess provided in the dust intrusion prevention tape 3. The tape 3 for preventing dust intrusion according to the present embodiment is made of polyester and has a thickness of about 0.05 mm.

Reference numeral 4 denotes an outer peripheral frame which holds the liquid crystal display module and constitutes the main body of the liquid crystal display device, and is made of, for example, resin injection molding. 4a is a side surface portion provided on the left and right sides of the outer peripheral frame 4, 4b is a concave section of the outer peripheral frame provided inside from the left and right side surface portions 4a of the outer peripheral frame 4, and 4c is a protruding gate portion. The side surface portion 4a is a portion which is connected to the side surface portion 4a in a gate-holding manner at a plane higher than the side surface portion 4a and the concave portion 4b in cross section with the concave portion 4b in cross section interposed therebetween, and is a part of the side surface portion 4a. 4d is a space formed by the upper surface of the concave section 4a and the lower surface of the protruding gate section 4c, which serves as a slit hole.

Reference numeral 5 is a reflection sheet for reflecting the light emitted from the lamp on the entire back surface of the liquid crystal display module 1, and is made of, for example, a white polyester sheet. Reference numeral 5a is a positioning projection provided on the left and right of the reflection sheet 5. 6 is a spacer. Reference numeral 7 denotes a light guide plate for transmitting the light emitted from the lamp to the entire back surface of the liquid crystal display module 1, which is a part of the illumination unit, and is made of, for example, a transparent acrylic resin. Reference numeral 7 a denotes a concave positioning portion provided on the left and right for positioning the light guide plate 7 inside the outer peripheral frame 4.

In the liquid crystal display device 1 configured as described above, first, the liquid crystal module is attached to the outer peripheral frame 4. Next, an illumination unit section that illuminates the liquid crystal module from the back side is constructed. The light unit is placed inside the outer peripheral frame 4 in the order of the light guide plate 7 and the reflection sheet 5. The side surfaces of the light guide plate 7 and the reflection sheet 5 are surrounded by the side surface portion 4 a of the outer peripheral frame 4. Also, the light guide plate 7 has concave positioning portions 7a on the left and right,
The side surface portion 4 of the outer peripheral frame 4 is provided on the left and right positioning portions 7a.
The light guide plate 7 is arranged on the outer peripheral frame 4 so that the concave portion 4b provided inside from a is inserted. The concave positioning portion 7a of the light guide plate 7 is provided with the concave portion 4b in cross section of the outer peripheral frame 4.
Therefore, the light guide plate 7 can be positioned in the front-rear direction and the left-right direction in the outer peripheral frame 4.

Next, the reflection sheet 5 is placed on the light guide plate 7. Here, the positioning portion 7 of the light guide plate 7 is also provided on the reflection sheet 5.
When the positioning portion having the same size as a is provided, the reflection sheet 5 is, for example, a polyester sheet and has a small thickness.
If the side surface portion 4a of the outer peripheral frame 4 is not sufficiently higher than the surface of the light guide plate 7, when the liquid crystal display device 1 is subjected to shock or vibration, the reflection sheet 5 will move over the side surface portion 4a of the outer peripheral frame 4 and be displaced. I will end up. Therefore, the reflection sheet 5 is provided with a locking projection 5a, and the outer peripheral frame 4 is provided with a slit hole 4d so that the locking projection 5a can be positioned on a surface higher than the side surface portion 4a of the outer peripheral frame 4. Slit hole 4d
When the outer peripheral frame 4 is injection-molded, the concave section 4b
And the side surface portion 4a and the concave portion 4b with the concave portion 4b in between.
It is formed by providing a projecting gate portion 4c having a shape that is connected like a gate at a surface higher than b. As a result, a space and a slit hole 4d are formed between the lower surface of the protruding gate portion 4c and the upper surface of the concave portion 4b in cross section. The reflection sheet 5 can be positioned by inserting the locking projection 5a of the reflection sheet 5 into the slit hole 4d in this space. When the protruding gate portion 4c is provided by injection molding, the slit hole 4 is formed.
Since a space is formed under d, external dust enters from this space. Therefore, the spacer 6 is attached or fitted with a double-sided tape or the like on the lower side of the locking projection 5a of the reflection sheet 5 and inside the concave section 4b of the outer peripheral frame 4.

The spacer 6 for preventing dust invasion is arranged so as to fill the concave inner side of the concave section 4b of the outer peripheral frame 4, and an elastically deformable member such as urethane rubber is preferable. Spacer 6 to prevent dust from entering
Is a plate-like elastic member having a size that fits inside the concave section 4b of the outer peripheral frame 4, and its size is approximately the same as or slightly larger than the inner portion of the concave section 4b. When urethane rubber is used, a force is applied in the direction of expanding the concave inner side of the concave section 4b due to its elasticity,
Moreover, since the coefficient of friction with the resin outer peripheral frame 4 is high,
Positional deviation does not occur easily and can be attached without using double-sided tape. The spacer 6 for preventing dust intrusion may be made of the same material as the resin outer peripheral frame 4. In this case, since there is no elasticity, the dimension may be almost the same as the inner portion of the concave portion 4b in cross section, and a double-sided tape may be used to prevent displacement.

Further, since the end surface of the spacer 6 extends to the outside of the end surface of the light guide plate 7, even if dust adheres to the end surface of the spacer 6, it is separated from the end surface of the light guide plate 7 and therefore the light guide plate 7 and the reflection sheet. Less susceptible to static electricity due to 5. In particular, if urethane rubber is used for the spacer 6,
Since static electricity is less likely to be generated in the urethane rubber, it is possible to obtain an effect that dust is less likely to be attracted to the end surface of the spacer 6.

Next, the back cover 2 is attached to the outer peripheral frame 4 to form an illumination unit section. In order to position the reflection sheet 5 by the locking projections 5a of the reflection sheet 5, the outer peripheral frame 4 is provided with a projection gate portion 4c. However, since this is higher than the side surface portion 4a, the back cover 2 has this projection. In order to cover the protruding gate portion 4c, the squeezing processing is partially performed to provide the squeezing processing portion 2a. By providing the trapezoidal squeezed portion 2a by press working, the back cover 2 has a crevice-processed portion 2b and a gap 2d formed by press working. After attaching the back cover 2, a tape 3 for preventing dust intrusion is attached. The tape 3 for preventing dust intrusion is provided with the concave portion 3a. Therefore, when this portion is attached so as to come to the bent portion 2c of the back cover 2, it is on the left and right of the squeezed portion 2a of the back cover 2. , The bite 2b and the gap 2d can be covered.

As described above, according to this embodiment, even if the components constituting the liquid crystal display device have a cracked portion or a gap by press working or a gap in the internal structure, the liquid crystal It is possible to prevent dust from entering from the outside of the display device. Note that, in addition to the above, a space or a gap is structurally formed in the outer peripheral frame 4 that constitutes the liquid crystal display device 1, so that external dust enters from that portion. It is possible to prevent dust from entering from the outside by attaching a spacer also to such a portion to close a space or a gap. Also, if it is a sheet metal part other than the back cover, there will be a bite and a gap by pressing or bending, so attach dust prevention tape to that part to prevent dust from entering from the outside. be able to.

[0034]

As described above, according to the present invention, even when the components constituting the liquid crystal display device have a crack or a gap due to the press working or a gap in the internal structure, the present invention has the above structure. It is possible to prevent dust from entering from the outside of the liquid crystal display device.

[0035]

[Brief description of drawings]

FIG. 1 is a rear perspective view of a liquid crystal display device according to an embodiment of the present invention.

FIG. 2 is a rear view of the liquid crystal display device according to the embodiment of the present invention.

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

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

FIG. 5 is an exploded rear view of the liquid crystal display device according to the embodiment of the present invention.

FIG. 6 is an exploded perspective view of a conventional liquid crystal display device.

FIG. 7 is a sectional view of a conventional liquid crystal display device.

FIG. 8 is an exploded rear view of a conventional liquid crystal display device

[Explanation of symbols]

1 ... Liquid crystal display module 2 …… Back cover 2a ... Squeezing part 2b ... Gripper processing part 2c ... Bent part 2d …… Gap 3 ...... Tape for preventing dust intrusion 3a ... recess 4 ... Outer frame 4a ... Side plate 4b: concave section 4c ... Projection gate 4d …… Slit hole 5 ... Reflective sheet 5a ... protrusion 6 ... Spacer 7 ...... Light guide plate 7a ... Positioning unit

Claims (5)

[Claims] 1. A light guide plate which constitutes at least an illumination unit, a reflection sheet which is arranged on the back side of the light guide plate, an outer peripheral frame which holds these from the outer peripheral side, and a back cover which holds these from the back side. A liquid crystal display device having a slit hole formed in a side surface portion of the outer peripheral frame for passing the locking projection of the reflection sheet, and a concave section having a concave section inside the slit hole. A liquid crystal display device, characterized in that a spacer for preventing dust intrusion is attached to the inside of the recessed section, and the end face of the attached spacer extends beyond the end face of the light guide plate. 2. A light guide plate which constitutes at least an illumination unit, a reflection sheet which is arranged on the back side of the light guide plate, an outer peripheral frame which holds these from the outer peripheral side, and a back cover which holds these from the back side. In the liquid crystal display device, a tape for preventing dust intrusion is attached so as to cover a gap formed at a contact portion between the outer peripheral frame and the back cover. 3. A locking projection is formed on the reflection sheet, and a gap formed at a contact portion between the outer peripheral frame and the back cover is formed to allow the locking projection of the reflection sheet to pass through a side surface of the outer peripheral frame. Is a gap formed between the formed slit hole and the left and right of the squeezed portion provided on the back cover to cover the slit hole, and the dust intrusion prevention tape is provided on the left and right of the squeezed portion of the back cover. The liquid crystal display device according to claim 2, further comprising left and right side portions that cover at least the gap that can be formed. 4. A light guide plate constituting at least an illumination unit, a reflection sheet arranged on the back surface side of the light guide plate, an outer peripheral frame for holding these from the outer peripheral side, and a back cover for holding these from the back surface side. , Having a slit hole formed in the side surface portion of the outer peripheral frame for passing the locking projection of the reflection sheet, and a concave section having a concave section inside the slit hole, corresponding to these positions In a liquid crystal display device having a gap left and right of a squeezed portion provided on the back cover, a spacer for preventing dust intrusion is attached inside the concave portion of the outer frame,
The end face of the attached spacer extends to the outside of the end face of the light guide plate, and dust-prevention tape is attached that has left and right side portions that cover at least the gap formed on the left and right of the squeezed portion of the back cover. Liquid crystal display device characterized by. 5. The dust-preventing spacer is a plate-shaped elastic member having a size that fits inside the center of the recessed section of the outer peripheral frame. Liquid crystal display device.