JP2840588B2 - Liquid crystal display - Google Patents

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 provided with a lighting device.

[0002]

2. Description of the Related Art Conventionally, a liquid crystal display device is provided with an illuminating device behind a liquid crystal cell. This illuminator used a fluorescent lamp covered with a reflecting mirror, but was thicker to uniformly illuminate a wide display surface. Therefore, Japanese Patent Application Laid-Open No. 64-782
As disclosed in Japanese Patent Publication No. 83, an apparatus has been proposed in which a light guide is used and a light source is provided on a side surface thereof to reduce the thickness.

However, in this device, since the liquid crystal cell, the light guide, and the light source are arranged and integrated in the frame, there is a problem that it is difficult to remove the light source that is frequently replaced due to failure or life. .

[0004] On the other hand, as a technique related to attachment and detachment of a light source, those disclosed in Japanese Utility Model Laid-Open Nos. 62-121885 and 62-173755 are known.

[0005] The former discloses a structure in which a fluorescent tube unit is detachably attached to a case in which a liquid crystal display is mounted, thereby improving the workability of replacing the fluorescent tube. However, since the light guide is attached and detached simultaneously with attachment and detachment of the fluorescent tube,
When the fluorescent tube is attached or detached, dust easily adheres between the liquid crystal display and the light guide plate, and the dust caused by the dust appears on the display surface of the liquid crystal display, resulting in a new problem that display quality deteriorates.

The latter includes a light source section including a halogen lamp and the like in a lower body and a liquid crystal light shutter and a cylindrical optical transmission body in an upper body of upper and lower bodies which can be freely opened and closed around a hinge. A structure is disclosed in which the optical head is fixed and the light source unit and the optical head are reliably positioned by opening and closing the upper body about the hinge. However, the structure in which the light source unit is mounted on the optical head is a very large structure because it is the entire structure of the apparatus including the upper and lower bodies and the hinge that allows the body to open and close. In addition, since the light source unit and the optical head are attached and detached each time the upper body is opened and closed, even when it is not necessary to replace the lamp of the light source unit, the light source unit is exposed and dust adheres to the light source unit. It is also an easy structure.

[0007]

SUMMARY OF THE INVENTION In consideration of this point, the present invention provides a liquid crystal display device that performs illumination using a light guide.
An object of the present invention is to provide a thin display device in which a light source can be easily attached and detached without affecting a display state, and a structure for attachment and detachment is simplified.

[0008]

A liquid crystal display device according to the present invention comprises a liquid crystal cell, a light guide disposed on the back of the liquid crystal cell, and a side of the light guide facing a side surface of the light guide. In a liquid crystal display device having a linear light source disposed therein and a lamp house accommodating the linear light source therein, the liquid crystal cell and the light guide are disposed between a base and a frame, and a flat main body is formed. Constitute
A light source section is formed by disposing the linear light source in the lamp house, and a connecting section is provided between the main body section and the light source section so as to connect them so as to form a single flat plate. The light source unit is attached to the main body from outside the main body by means of a unit.

In the liquid crystal display device according to the present invention, a liquid crystal cell, a light guide disposed on the back of the liquid crystal cell, and a circuit board are disposed and fixed between the base and the frame, and the side surfaces of the light guide are fixed. A flat main body facing the outside, and a light source having a linear light source inside a lamp house independent of the main body are provided, and both are a single flat plate between the main body and the light source. A connecting portion for connecting the two is provided so that the linear light source is opposed to the side surface of the light guide by the connecting portion, and the light source portion is mounted on a side portion of the main body portion. Features.

With the above arrangement, the light source can be mounted after the liquid crystal cell, the light guide, the circuit board, etc. are arranged and fixed between the base and the frame, and the main body is assembled. Workability can be improved. In addition, when the main body is disassembled when replacing the linear light source, dust and the like are likely to be generated between the liquid crystal cell and the light guide, which is likely to cause a deterioration in display quality. Since the independent lamp house is mounted, the lamp house can be removed without disassembling the main body, and it is possible to effectively prevent the deterioration of display quality due to the adhesion of dust or the like. Furthermore, by connecting the main body part and the light source part by a connecting part to form one flat plate, the device can be made thinner and its handling can be facilitated.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a sectional view of a main part of a liquid crystal display device according to an embodiment of the present invention, and FIG. 2 is an exploded perspective view thereof. The liquid crystal display device of the embodiment is mainly composed of a main body and a light source.

First, the main body will be described. In the drawing, reference numeral 1 denotes a base made of an iron plate having a rising portion and a mounting surface in the periphery. Reference numeral 2 denotes a circuit board made of glass epoxy or paper phenol, on which an active element (not shown) is disposed. Reference numeral 3 denotes a substantially rectangular parallelepiped light guide made of acrylic resin. Reference numeral 4 denotes a liquid crystal cell including a field effect type liquid crystal panel and polarizers arranged above and below the panel. Reference numeral 5 denotes a holding frame made of an iron plate having an opening near the center, and has fixing claws on two opposing sides.

A hole is provided in the base 1 and the circuit board 2 at a position facing the claw of the holding frame 5.
A circuit board 2, a light guide 3, and a liquid crystal cell 4 are sequentially placed on a base 1.
After the holding frame 5 is placed and the claws of the holding frame 5 are inserted into the holes of the circuit board 2 and the base 1, the components are fixed by twisting. In this manner, a flat main body in which the liquid crystal cell 4, the light guide 3, the circuit board 2, and the like are accommodated and fixed between the base 1 and the frame 5 is formed. Here, the main body is configured such that one side surface of the light guide 3 faces the outside of the main body.

Next, a description will be given of a light source unit mounted on the main body unit from the outside. In the drawing, reference numeral 6 denotes a reflection sheet made of a polyester film or polycarbonate provided with a metal deposition film or a mirror-finished aluminum foil. The reflection sheet 6 is provided as needed to reflect the light source. In a case where the same function is achieved by another configuration, for example, a configuration in which the reflection sheet is not provided as in the related art is known. You can also. Reference numeral 7 denotes a linear light source formed of a rod-shaped fluorescent lamp, and has a light source fixture 8 formed of a substantially rectangular parallelepiped insulator at both ends thereof.
A lead wire set 9 composed of a lead wire and a connector is connected to the light source fixture 8.

Reference numeral 10 denotes a lamp house which is independent of the main body, and comprises an upper lamp house 11 and a lower lamp house 12, both of which are made of iron plates. The upper lamp house 11 has a rising portion, and the rising portion has a stepped bent portion and a 3
It has an upper hinge portion 13 which has been cut out at two places.
Similarly, the lower lamp house 12 also has a rising portion, a stepped bent portion, and a lower hinge portion 14 provided with three notches. The upper hinge portion 13 and the lower hinge portion 14 are engaged to form the lamp house 10 having the hinge portion 15. The hinge 15 allows the linear light source 7, the reflection sheet 6, and the light source fixture 8 to be disposed inside the lamp house 10 by opening the edge of the lamp house 10 opposite to the hinge 15. When the reflection sheet 6 is not provided, the lamp house 10 also functions as a reflection member of the light source 6 to some extent.

The upper lamp house 11, the other edge of the reflection sheet 6, the light guide 3, the circuit board 2, and the reflection sheet 6
A nut 17 is fastened through a small screw 16 into one end of the lower lamp house 12 and a hole provided in each of the lower lamp houses 12 to complete the present apparatus. Here, the small screw 16 and the nut 17
Constitutes a connecting portion that connects the main body portion and the light source portion, and the connecting portion forms the device into one flat plate.

With the above structure, one edge of the reflection sheet 6 is adhered to the edge of the back surface of the circuit board 2 or the edge of the back surface of the light guide 3, and the other edge of the reflection sheet 6 is The edge is adhered to the surface of the light guide 3. Further, since the reflection sheet 6 has extensibility, the reflection sheet 6 is disposed so as to wrap the light source while maintaining a certain space between the reflection sheet 6 and the linear light source 7, so that the reflection efficiency is good.

Further, since the lamp house 10 has a hinge portion, one side edge is opened to open the linear light source 7 and the reflection sheet 6.
Can be attached and detached. The lamp house 10 containing the linear light source 7 is provided with a main body, that is, a holding frame 5.
Base 1 on which liquid crystal cell 4, light guide 3 and circuit board 2 are arranged
Not integrated with Therefore, the linear light source can be easily attached and detached.

The assembling procedure for mounting the light source unit on the main body and the procedure for replacing the linear light source 7 are described below.
Although the description is simplified as matters that can be easily understood by those skilled in the art based on the description of the above-described embodiment, supplementary explanations will be given below with additional matters obvious to those skilled in the art for reference.

First, a supplementary description will be given of an assembling procedure when the light source unit is mounted on the main body. First, an adhesive is applied to one edge of the reflection sheet 6 and fixed to the edge of the back surface of the circuit board 2. Alternatively, before fixing the light guide 3 described above,
The reflection sheet 6 having one edge coated with an adhesive is connected to the light guide 3.
May be fixed to the edge of the back surface of. Next, after enclosing the linear light source 7 inside the reflection sheet 6, the reflection sheet 6 having the other edge coated with an adhesive is fixed to the edge of the surface of the light guide 3. Subsequently, the edge of the lamp house 10 opposite to the hinge portion 15 is opened, and the light source fixtures 8 at both ends of the linear light source 7 are positioned and arranged on the lower lamp house 12.
Is closed, the linear light source 7 and the reflection sheet 6 are accommodated inside the lamp house 10. Subsequently, small holes are respectively formed in the upper lamp house 11 and the other edge of the reflection sheet 6, the light guide 3, the circuit board 2, one edge of the reflection sheet 6, and the lower lamp house 12. The liquid crystal display device is completed by attaching the light source unit to the main body by fastening the nut 17 through the screw 16. As described above, since the light source unit can be mounted from outside the main body after the main body is assembled, the workability of assembling the liquid crystal display device can be improved.

Then, when the light source 7 is turned on, a part of the light of the light source 7 is directly incident on the side surface of the light guide 3, and the other part of the light of the light source 7 is reflected by the reflection sheet 6, and then the light is guided. Body 3
Incident indirectly on the side surface of.

When the reflection sheet 6 is not provided as is conventionally known, the edge of the lamp house 10 opposite to the hinge portion 15 is opened, and the light source fixtures 8 at both ends of the linear light source 7 are attached to the lower lamp. The lamp house 10 is positioned and arranged on the house 12.
Is closed to dispose and fix the linear light source 7 inside the lamp house 10. Subsequently, a nut 17 is fastened through a small screw 16 into a hole provided in each of the upper lamp house 11, the light guide 3, the circuit board 2, and the lower lamp house 12, so that the light source section is mounted on the main body. Thus, the liquid crystal display device is completed. Also in this case, since the light source unit can be mounted after the main body unit is assembled, the workability of assembling the liquid crystal display device can be improved. In addition, part of the light of the light source 7 directly enters the side surface of the light guide 3, and after being reflected by another lamp house 10, the light of the light source 7 indirectly enters the side surface of the light guide 3.

Next, the case where the linear light source 7 is replaced will be supplementarily described. First, the nut 17 is loosened and the small screw 16 is removed. Next, the edge of the lamp house 10 opposite to the hinge portion 15 is opened to expose the other end of the reflection sheet 6, and the adhesive with the surface of the light guide 3 is peeled off to remove the other end of the reflection sheet 6. The light guide 3 is peeled off from the surface. Here, the adhesion between the reflection sheet 6 and the light guide 3 may be set to a degree that is weak enough to perform temporary fixing, so that the reflection sheet 6 can be easily peeled off. That is, the reflection sheet 6 and the light guide 3
Is fixed by fastening the small screw 16 and the nut 17 via the lamp house 10, so there is almost no necessity of firmly bonding. Next, the reflection sheet 6
The linear light source 7 is replaced in a state where the other end of the linear light source 7 is separated from the light guide 3. When the replacement is completed, the replacement work of the linear light source is completed by assembling in the same procedure as in the case of assembling. Here, when the linear light source is replaced, it is not necessary to disassemble the main body, so that it is possible to avoid a decrease in display quality caused by dust and the like attached to the disassembly of the main body. Since the main body does not need to be disassembled, light source replacement workability can be improved as compared with the case where the main body needs to be disassembled.

When replacing the linear light source 7 without the reflection sheet 6, the nut 17 is loosened and the small screw 16 is removed.
The lamp housing 10 is removed from the side surface of the light guide 3 by opening the edge opposite to the hinge portion 15 of the lamp house 10. Next, the linear light source 7 is replaced. When the replacement is completed, the replacement work of the linear light source is completed by assembling in the same procedure as in the case of assembling. Also in this case, when the linear light source is replaced, it is not necessary to disassemble the main body, so that it is possible to avoid a decrease in display quality caused by dust or the like attached due to the disassembly of the main body. ,
Since the main body does not need to be disassembled, the light source replacement workability can be improved as compared with the case where the main body needs to be disassembled.

[0025]

As described above, according to the present invention, the liquid crystal cell, the light guide disposed on the back surface of the liquid crystal cell, and the light guide disposed on the side of the light guide facing the side surface of the light guide. In a liquid crystal display device comprising a linear light source and a lamp house accommodating the linear light source therein, the liquid crystal cell and the light guide are arranged between a base and a frame to form a flat main body. A light source portion is formed by arranging the linear light source in the lamp house, and a connecting portion is provided between the main body portion and the light source portion so as to connect them so as to form a single flat plate. Since the light source unit is attached to the main unit from outside the main unit by the connecting unit, the light source unit can be attached after the main unit is assembled, and the mounting workability of the linear light source can be improved. In addition, if the main body is disassembled when the linear light source is replaced, dust and the like are likely to be adhered between the liquid crystal cell and the light guide, which is likely to cause a reduction in display quality. The light source unit can be removed without disassembling the main unit because it is attached to the main unit from the outside of the main unit, improving the workability of replacing the linear light source and improving the display quality due to dust adhesion. The deterioration can be effectively prevented, and the display quality can be maintained in a good state. Furthermore, by connecting the main body portion and the light source portion by a connecting portion to form one flat plate, the device can be made thinner and the handling thereof can be facilitated.

[Brief description of the drawings]

FIG. 1 is a sectional view of a main part of a liquid crystal display device according to an embodiment of the present invention.

FIG. 2 is an exploded perspective view of the embodiment.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Base 2 Circuit board 3 Light guide 4 Liquid crystal cell 5 Holding frame 6 Reflection sheet 7 Linear light source 10 Lamp house 15 Hinge part

──────────────────────────────────────────────────続 き Continuation of the front page (72) Inventor Norio 3-201 Minamiyoshikata, Tottori City, Tottori Prefecture Tottori Sanyo Electric Co., Ltd. 62-173755 (JP, U) (58) Fields investigated (Int. Cl. ⁶ , DB name) G02F 1/1335 530

Claims (3)

(57) [Claims] A liquid crystal cell, a light guide disposed on the back surface of the liquid crystal cell, a linear light source disposed on a side of the light guide and facing a side surface of the light guide , in the liquid crystal display device having a lamp house accommodating the said linear light source therein, the liquid crystal cell between the base and the frame member, and placing the light guide constitutes a flat body portion, said lamp house by arranging the linear light source in addition to constituting the light source section, and the body portion of the light source unit
A link connecting the two so that they form a single plate
A liquid crystal display device comprising: a connection portion; and the light source portion is attached to the main body portion from outside the main body portion by the connection portion . 2. A flat plate in which a liquid crystal cell, a light guide disposed on the back of the liquid crystal cell, and a circuit board are arranged and fixed between a base and a frame, and a side surface of the light guide faces outside. and Jo of the main body portion provided with a light source unit having a linear light source in the interior of the separate lamp house and the body portion, both so both become a single flat between the light source portion and the body portion A liquid crystal display, wherein the light source unit is mounted on a side of the main body in a state where a connecting portion for connecting a user is provided, and the linear light source faces the side surface of the light guide by the connecting portion. apparatus. 3. The liquid crystal display device according to claim 1, wherein the lamp house is detachably attached to the main body.