JPH1054986A - Liquid crystal display device, backlight panel, and method of manufacturing liquid crystal display device - Google Patents

Abstract

(57) [Object] To provide a liquid crystal display device, a backlight panel, and a method of manufacturing a liquid crystal display device, which can be reduced in size or simplified in a manufacturing process. SOLUTION: A liquid crystal panel 10 in which liquid crystal is sandwiched between a pair of substrates 12, 14, an electrode 12a provided inside the substrate 12, and an edge for converting light of a light emitting unit 22 disposed at an end into a surface light source. -Type backlight panel 20,
The substrate 12 is arranged to be displaced from the substrate 14 to form a projection 12a, and the electrode 12b is formed on the projection 12a.
Are exposed, and the light emitting section 22 of the backlight panel 20 is arranged in a region facing the protruding section 12a.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a liquid crystal display device, a backlight panel, and a method for manufacturing a liquid crystal display device.

[0002]

BACKGROUND OF THE INVENTION Since a liquid crystal display is a non-light emitting display, a backlight is used so that it can be used in a dark place. Edge type backlights are available. Since the edge type backlight is provided with the light source at the side end of the illuminating surface, the outer dimensions become large. In particular, in the case of a backlight in which a plurality of point light sources are used as a surface light source by devising the shape of the reflection surface, some distance is required from the point light source to the illuminating surface. This has hindered miniaturization of the liquid crystal display device.

Alternatively, when attaching the backlight to another member, a spacer has been installed under the backlight in order to avoid electric components and the like.
This step not only increased the number of manufacturing steps but also made it difficult to perform positioning.

Alternatively, it has been difficult to cut a long cable into a predetermined length and cut it into an accurate length when connecting the cable to a circuit board. If the dimensions are too short, connection cannot be made, and if the dimensions are too long, sagging occurs to take up space, which hinders miniaturization of the liquid crystal display device.

An object of the present invention is to solve the above-mentioned problems, and an object of the present invention is to provide a liquid crystal display device, a backlight panel, and a method of manufacturing a liquid crystal display device, which can be downsized or the manufacturing process can be simplified. Is to provide.

[0006]

A liquid crystal display device according to the present invention comprises: a liquid crystal panel having liquid crystal sandwiched between a pair of substrates; a pair of electrodes provided on opposite sides of the pair of substrates; An edge-type backlight panel that turns at least one light source arranged as a surface light source, wherein the pair of substrates are arranged so as to be shifted from each other to form a protrusion, and the electrode is formed on the protrusion. Is exposed, and the light source of the backlight panel is arranged in a region facing the protrusion.

In the present invention, since the electrodes are exposed on the protruding portions, electrical connection with the outside is facilitated.
The projecting portion is a region where the liquid crystal is not interposed since the pair of substrates are formed so as to be shifted from each other. Therefore, the protrusion is formed outside the liquid crystal display area. Further, the formation of the protruding portion increases the distance from the side end of the protruding portion to the liquid crystal display area.

On the other hand, an edge type backlight panel is
Some distance is required between the light source and the surface light source area. Therefore, by arranging the light source in a region facing the protrusion, the distance of the protrusion can be effectively used. Thus, the outer shape of the liquid crystal display device can be minimized.

[0009] The backlight panel includes a plurality of point light sources, an effective light emitting portion for uniformly forming a surface light source, and a transition region from the point light source to the effective light emitting portion. At least a part and the point light source may be arranged in a region facing the protrusion.

As described above, in a configuration in which a plurality of point light sources are used as a surface light source, there is a distance between adjacent point light sources, so that the transition region becomes longer than when a line light source is used as a surface light source. Therefore, at this time, arranging at least a part of the transition area and the point light source in the area facing the protrusion is effective in minimizing the outer shape.

The present invention has a light source disposed at an end portion, and a light guide plate for guiding light from the light source and emitting the light in one surface direction to form a surface light source. The surface is processed to reflect light from the light source in the direction of the one surface, and a support portion is integrally formed in a region other than the effective light emitting portion that uniformly turns into a surface light source. An edge type backlight panel is provided.

In the present invention, the light source at the end is made into a surface light source by a light guide plate, and light is emitted in the surface direction. For example, by subjecting the back surface of the light guide plate to Fresnel mirror processing or grain processing, light can be reflected in the plane direction.

Further, in the present invention, the supporting portion is formed integrally with the backlight panel. This support is
Since it is formed in a region other than the effective light emitting portion where uniform surface light source is required, proper reflection of light is not hindered. Thus, since the backlight panel according to the present invention has the support portion, it can be easily attached to another member.

It is preferable that the supporting portion has a positioning portion for positioning with another member. In this way, not only mounting but also positioning can be easily performed.

A liquid crystal display device according to the present invention has the above-mentioned backlight panel, a liquid crystal panel is attached to the one surface, and a circuit board is attached to the other surface.

According to the present invention, the circuit board is mounted on the surface of the backlight panel on which the support is formed. Therefore, the circuit board can be mounted by effectively utilizing the space formed between the support portion and the surface of the backlight panel. Thus, the thickness of the liquid crystal display device can be reduced.

According to the present invention, there is provided a process for obtaining a connecting member by cutting a long cable for making an electrical connection longer than a required dimension, and disposing the connecting member in a direction different from a predetermined disposing direction. Toward, a step of electrically connecting the end to the circuit board, a step of bending the connection member to face the predetermined arrangement direction, and adjusting a bending position of the connection member,
Adjusting the disposition length of the connection member.

According to the present invention, even if there is an error in the length of the connecting member, the disposition length can be adjusted only by adjusting the bending position. By adjusting the disposition length of the connection member in this manner, workability when connecting the tip of the connection member to another member can be improved. Further, since the sag of the connection member can be minimized, the outer shape of the liquid crystal display device can be reduced.

[0019]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described below with reference to the drawings. FIG. 2 is an exploded perspective view schematically showing the liquid crystal display device according to the embodiment of the present invention. FIG. 1 is a side sectional view of the liquid crystal display device according to the present embodiment. As shown in these drawings, this liquid crystal display device includes a liquid crystal panel 10, a backlight panel 20, and a circuit board 30.

The liquid crystal panel 10 has a pair of substrates 12 and 14 made of glass sandwiching liquid crystal (not shown).
Polarizing plates 16 and 18 are attached to the outer surfaces of the substrates 12 and 14, respectively. One substrate 12 has a protruding portion 12a that protrudes in a state shifted from the other substrate 14, and the other substrate 14 has a protruding portion 14a that protrudes in a state shifted from one substrate 12.

A pair of electrodes 12b, 14b for driving the liquid crystal are provided on the opposing surfaces of the substrates 12, 14, respectively.
Is provided. The ends of the electrodes 12b, 14b are exposed on the protruding portions 12a, 14a.

Liquid crystal panel 10 and backlight panel 20
Is adhered and fixed by, for example, a tape-like member provided with an adhesive layer on both surfaces indicated by hatching in FIG. At this time, it is preferable that the tape-shaped member is provided in a region other than the region corresponding to the effective light emitting unit 28 (outside the region). Further, the inside is a space in the present embodiment, but may be in any state as long as it does not hinder the optical path.

The backlight panel 20 includes a light emitting section 22,
It has a light guide plate part 24 and a support part 26. The light emitting unit 22
It includes a light emitting element 22a as a plurality of point light sources. The light guide plate portion 24 is transparent so that light from the light emitting element 22a can be guided. Also, on one surface of the light guide plate portion 24,
Fresnel mirror processing is performed so that light can be emitted to the other surface (see FIG. 1). Further, a reflection plate 24a is attached to the surface on which the Fresnel mirror processing has been performed to prevent light leakage.

As described above, the backlight panel 20
It is of the edge type. Therefore, the light emitting part 22 is provided to protrude to the side of the light guide plate part 24 that emits the surface light. Further, as described above, the substrates 12, 14 of the liquid crystal panel 10 are provided.
Also, the protrusions 12a protruding to the side of the region sandwiching the liquid crystal,
14a are formed.

Therefore, in the present embodiment, the light emitting unit 22 is
By arranging it so as to face the protruding portion 12a, the external dimensions are minimized. That is, the projecting portion 12a of the liquid crystal panel 10 and the light emitting portion 22 of the backlight panel 20 are
By projecting in the same direction, no useless space is created.

In this embodiment, a plurality of light emitting elements 2
The light from 2a is turned into a surface light source in the light guide plate portion 24. Therefore, a certain distance is required to convert the light from the light emitting element 22a as a point light source into a surface light source.

That is, the adjacent light emitting elements 22a, 22
Since there is a distance between “a” and “a”, a surface light source cannot be formed near the light emitting element 22a. As shown in FIG. 1, a transition region 29 having a length l2 is required before reaching an effective light emitting portion 28 (length l1) which requires a uniform surface light source.

As described above, the backlight panel 20
Since the point light source is a surface light source, the distance protruding outward from the effective light emitting unit 28 is increased. Therefore, the effective light emitting unit 28
Arranging the portion protruding from the liquid crystal panel 10 so as to face the protruding portion 12a of the liquid crystal panel 10 is effective in reducing the external dimensions.

The supporting portion 26 is formed on the surface of the light guide plate portion 24 on which the above-described Fresnel mirror processing has been performed, so that the backlight panel 20 can be easily attached to other members. Further, since the support portion 26 is formed integrally with the light guide plate portion 24, the workability can be improved and the manufacturing cost can be reduced as compared with the case where a spacer or the like is used as a separate member. Further, the support portion 26
Since it is formed avoiding the effective light emitting portion 28, it does not hinder the Fresnel mirror processing. That is, it does not prevent the light from the light emitting element 22a from becoming a surface light source.

Further, the supporting portion 26 has a projection 26a at the lower end.
Therefore, if a hole is formed in another member, positioning can be easily performed. The protrusion 26a
Is preferably provided in plurality.

Next, the circuit board 30 includes a drive circuit and a power supply circuit for the liquid crystal panel 10 and the light emitting element 22a. Therefore, the circuit board 30 and the liquid crystal panel 10 are electrically connected by thermocompression bonding of the heat seal 32.
Alternatively, instead of the heat seal 32, a TAB having a semiconductor chip mounted thereon is used, and the TAB is used.
May be electrically connected to the liquid crystal panel 10 by thermocompression bonding using an anisotropic conductive film. The circuit board 30 and the light emitting element 22a are electrically connected by soldering the leads 34.

The circuit board 30 is a surface on which the support portion 26 is formed, and is attached so as to avoid the support portion 26. Therefore, the backlight panel 2
When 0 is attached, the space formed between the backlight unit 20 and the support unit 26 can be effectively utilized.

A flat cable 36 is soldered to the circuit board 30 for further electrical connection. FIG. 3 is a diagram illustrating a process of adjusting the length of the flat cable 36.

The flat cable 36 has a large number of leads arranged in parallel and both sides of which are sandwiched between tape-like insulators, and is integrated so that it can be freely bent with flexibility. .

As shown in FIG. 3, the flat cable 36 has a predetermined length 1 from the end of the backlight panel 20.
Mounted with only 3 protruding. Here, it is difficult to reduce the dimensional error of the flat cable 36.
For example, the flat cable 36 is cut from a length of several meters to a required length and used, but it is difficult to reduce a dimensional error at that time. In addition, it is difficult to reduce the dimensional error when mounting on a board. Therefore, even if there is a large error in the length of the flat cable 36, the flat cable 36 is attached by the following method to absorb the error.

First, the flat cable 36 is cut from a long state so as to be longer than a length l4 required in the arrangement direction. Specifically, there may be an error as long as the length is equal to or greater than the length l4 plus the length at which the flat cable 36 can be folded back.

Then, as shown by a two-dot chain line in FIG. 3, the end of the flat cable 36 is soldered in a direction opposite to the disposing direction. Specifically, soldering is performed by exposing the leads at the ends.

Next, the flat cable 36 is folded back in the direction of arrangement. Thus, the tip of the flat cable 36 protrudes from the end of the backlight panel 20. Then, by adjusting the bending position, the protruding length can be reduced to l3.

According to the above steps, the flat cable 3
Even if there is an error in the length of 6, the error can be absorbed by adjusting the bending position. Since this adjustment operation is simpler than adjusting the dimensions accurately, workability can be improved. Conventionally, when the error in the length of the flat cable is large, the flat cable is slackened by an amount longer than the predetermined length. Can be. If there is no slack, there is no useless space, and the liquid crystal display device can be made thinner. Further, the direction in which the flat cable 36 is bent is not limited to the direction shown in FIG. For example, the flat cable 36 may be bent so that the direction before the bending and the direction after the bending intersect.

The present invention is not limited to the above embodiment, and various modifications are possible. FIG. 4A and FIG. 4B are schematic diagrams showing a modification of the embodiment.

For example, as shown in FIG. 4A, a projection 58 formed by the light emitting section 56 of the backlight panel 54 is accommodated in a space below the projection 52a of the substrate 52 above the liquid crystal panel 50. May be.

Alternatively, as shown in FIG. 4B, the backlight panel 66 may be attached so that the light emitting section 64 is arranged below the projection 62a of the substrate 62 below the liquid crystal panel 60. .

[0043]

[Brief description of the drawings]

FIG. 1 is a side sectional view of a liquid crystal display device according to an embodiment.

FIG. 2 is an exploded perspective view schematically showing a liquid crystal display device according to an embodiment of the present invention.

FIG. 3 is a diagram illustrating a process of adjusting an arrangement length of a flat cable.

FIG. 4 is a schematic diagram showing a modification of the embodiment.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Liquid crystal panel 12 Substrate 12a Projection 12b Electrode 14 Substrate 14a Projection 14b Electrode 20 Backlight panel 22 Light emitting part 22a Light emitting element (point light source) 24 Light guide plate part 24a Reflective plate 26 Support part 26a Projection (positioning part) 28 Effective light emission Part 29 Transient area 30 Circuit board 36 Flat cable (connection member)

Claims (6)

[Claims] 1. A liquid crystal panel in which liquid crystal is sandwiched between a pair of substrates, a pair of electrodes provided on opposing surfaces of the pair of substrates, and at least one light source disposed at an end is a surface light source. An edge-type backlight panel, wherein the pair of substrates are arranged offset from each other to form a protrusion, and one of the electrodes is exposed on the protrusion, and a light source of the backlight panel is A liquid crystal display device arranged in a region facing the protrusion. 2. The liquid crystal display device according to claim 1, wherein the backlight panel includes a plurality of point light sources, an effective light emitting unit that uniformly converts the light source into a surface light source, and a unit extending from the point light source to the effective light emitting unit. A transition region, wherein at least a part of the transition region and the point light source are arranged in a region facing the protrusion. 3. A light source disposed at an end, and a light guide plate for guiding light from the light source and emitting the light in one surface direction to form a surface light source, wherein the light guide plate is provided on the other surface of the light guide plate. Is processed to reflect the light from the light source in the direction of the one surface, and
An edge-type backlight panel in which a support portion is integrally formed in a region other than an effective light-emitting portion that uniformly becomes a surface light source. 4. The backlight panel according to claim 3, wherein the support section has a positioning section for positioning with another member. 5. A liquid crystal display device comprising the backlight panel according to claim 3 or 4, wherein a liquid crystal panel is attached to the one surface, and a circuit board is attached to the other surface. 6. A method for manufacturing a liquid crystal display device, comprising: a step of cutting a long cable for making an electrical connection longer than a required dimension to obtain a connection member; and disposing the connection member in a predetermined arrangement. A step of electrically connecting the end to the circuit board in a direction different from the direction, a step of bending the connection member to face the predetermined arrangement direction, and adjusting a bending position of the connection member. Adjusting the disposition length of the connection member; and a method for manufacturing a liquid crystal display device.