JPH11344938A - Light transmission type display device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a light transmission type liquid crystal display device in which metal shield cases of backlight units are not contacted each other and occurrence of dust caused by shaving is suppressed. SOLUTION: In this device, an angle between a bottom surface part 20c and an internal side surface part 20b of a back shield case 20 is an acute angle being smaller than 90 degrees, preferably 80-89 degrees. And a gap 28 exists among the inner side surface part 20b and a peripheral part of the back shield case 20, and a backlight unit 21 housed in a storing part.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to a light transmission type display device provided with an illuminating means such as a backlight on the back of a display panel.

[0002]

2. Description of the Related Art In recent years, a flat display device (flat display) represented by a liquid crystal display device has been characterized by being thin, light, and low in power consumption. It is used in various fields as a display device such as a navigation system.
Above all, a light transmission type liquid crystal display device configured to irradiate light from the back surface of a display surface with an illumination means such as a backlight has widened its use range because large display luminance can be obtained.

Hereinafter, a conventional light transmission type liquid crystal display device will be described with reference to the drawings.

This liquid crystal display device comprises a liquid crystal panel 1 having a liquid crystal layer sandwiched between a pair of transparent substrates, as shown in FIG. A drive circuit board 2 for driving, a TCP (tape carrier package) 3 for connecting the drive circuit board 2 and the liquid crystal panel 1 by a TAB method, and a plastic frame 4 for stably holding these connections and the like. The liquid crystal panel 1 includes a metal shield case 5 that accommodates these components, improves mechanical strength, and prevents generation of noise, and a backlight unit 6 disposed on the back surface of the liquid crystal panel 1. The metal shield case 5 includes a front shield case 7 disposed on the front side of the liquid crystal panel 1 and a back shield case 8 disposed on the back side. By fitting into the fitting hole 10 of the shield case 8,
Connected and fixed. In the drawings, reference numeral 11 denotes a silicone rubber serving as a cushioning material, and reference numeral 12 denotes an engaging claw portion of a drive circuit board provided on an inner bottom portion of the back shield case 8.

[0005]

However, in the above-described conventional light transmission type liquid crystal display device, the back shield case 8 is formed by bending a metal plate, and the bottom surface portion 8a and the backlight unit housing are formed. The bending angle between the inner side surface portion 8b forming the space is 90
Due to the design and fabrication as °, the bending deformation returns due to the springback of the metal after processing, and the angle between them was an obtuse angle greater than 90 °.

As a result, when the backlight unit 6 is stored on the back surface of the liquid crystal panel 1 or when the backlight unit 6 is removed for replacement, the backlight unit 6 is tilted and projected into the inner backlight unit storage space. There is a problem in that the edge is in contact with the edge of the inner side surface portion 8b of the shield case 8 and is scraped off to generate dust. Further, in the stored state, since the backlight unit 6 is always in contact with the inner side surface 8b (edge) of the back shield case 8, dust due to shavings is generated, which obstructs lighting and reduces display quality. Had been lowered.

SUMMARY OF THE INVENTION The present invention has been made to solve such a problem, and there is provided a light transmission type liquid crystal display device in which there is no contact with a metal shield case of a backlight unit and generation of dust due to shaving is suppressed. The purpose is to provide.

[0008]

According to the present invention, there is provided a light transmission type display device comprising: a light transmission type display panel having a light modulation layer sandwiched between a pair of transparent substrates; a driving circuit for driving the display panel; A display panel, a resin frame for stably maintaining the connection between the display panel and the drive circuit, a metal frame whose main part is formed by bending a metal plate, and which respectively accommodates the display panel and the resin frame; A light transmission type display device, comprising: lighting means housed and arranged on the back of the panel, wherein the driving circuit is held in a direction substantially perpendicular to a display surface of the display panel, wherein the lighting means; A gap is present between the metal frame and an edge of an inner side surface portion of the metal frame extending into the storage space in which the lighting unit is stored.

In the display device of the present invention, the above configuration prevents the backlight unit, which is the lighting means, from coming into contact with the edge of the inner side surface of the metal frame and being scraped off. Therefore, generation of dust due to scraping is suppressed, and high-quality display can be realized.

[0010] Further, in such a structure, the angle formed between the bottom surface portion and the inner side surface portion of the metal frame is smaller than 90 °,
More preferably, it can be realized by setting the angle to 80 ° to 89 °. That is, when the angle formed between the bottom surface portion and the inner side surface portion of the metal frame is an acute angle smaller than 90 °, for example, after forming by bending, even if the bending deformation is slightly returned by the spring back of the metal, it is possible to obtain these angles. Since the angle between them does not exceed 90 °, the backlight unit does not come into contact with the end of the inner side surface of the metal frame when mounting the backlight unit, etc. The generation of shaving dust, which is reduced, is suppressed. When the angle between the bottom surface and the inner side surface of the metal frame is larger than 80 °, the end of the inner side surface of the metal frame is not strongly pressed against the inner resin frame, and the resin frame is damaged. This is preferable because the opening of the storage space can be widened and the backlight unit can be easily mounted.

[0011]

Embodiments of the present invention will be described below with reference to the drawings.

A liquid crystal display device according to one embodiment of the present invention is a normally white mode light transmission type active matrix type liquid crystal display device having a display surface of 5 inches diagonal and capable of color display. It has.

In this liquid crystal display device, as shown in FIGS. 1 and 2, a liquid crystal layer for modulating light transmittance is sandwiched between a pair of transparent substrates (for example, a TFT array substrate and a color filter substrate). The liquid crystal panel 13, a signal line driving circuit board (hereinafter, referred to as X-PCB) 14 for driving signal lines and scanning lines of the liquid crystal panel 13, and a scanning line driving circuit board (hereinafter, referred to as Y-PCB). .)
A tape carrier package (hereinafter, referred to as X-TAB) 16 for connecting a signal line drive circuit, which connects the X-PCB 14 and the liquid crystal panel 13 (TFT array substrate) in a TAB method; A tape carrier package (hereinafter, referred to as Y-TAB) 17 for connecting a scanning line drive circuit, which connects the liquid crystal panel 13 to the liquid crystal panel 13 by a TAB method.
And a plastic frame 18 for stably maintaining the connection between the liquid crystal panel 13 and the above-described drive circuit and the like, and accommodating the plastic frame 18 to mechanically protect against external shocks and the like, and to generate noise and the like. A front shield case 19 and a back shield case 20 for preventing the
1 is provided.

The Y-PCB 15 is connected to an input FFC (flip-flop circuit) 22 for exchanging signals with the outside. Also, Y-PCB
A connection flexible member 23 is connected between the X-PCB 15 and the X-PCB 14, and through this member, the Y-PCB 15 is connected.
Supplies necessary signals to the X-PCB 14.

Next, the front and back shield cases accommodating the liquid crystal panel 13 and the like and the plastic frame 18 will be described in more detail with reference to FIG.

The front shield case 19 has a metal frame portion 19a having an opening for exposing the display surface 13a of the liquid crystal panel 13 on the main surface, and one long side and one short side of the metal frame portion 19a. And a metal side surface portion 19b extending in a direction substantially perpendicular to the display surface 13a of the liquid crystal panel 13 below (on the back side of the liquid crystal panel 13).
The metal side portion 19b forms a storage portion for the plastic frame 18, the X-TAB 16, and the Y-TAB 17. The plastic frame 18 has a resin frame 18 a having an opening slightly smaller than the main surface opening of the front shield case 19, and a liquid crystal below two sides corresponding to the metal side surface 19 b of the resin frame 18 a. And a resin side surface portion 18b extending in a direction substantially perpendicular to the display surface 13a of the panel 13.

A front shield case 19 is arranged on the front surface of the liquid crystal panel 13, and a peripheral portion of the TFT array substrate 24 forming the liquid crystal panel 13 is connected to the front shield case 19 via a silicon rubber 25a as a buffer. It is in contact with the pressing and fixing part of the metal frame part 19a. Further, a plastic frame 18 is disposed on the back of the liquid crystal panel 13, and the TFT array substrate 24 is provided with a resin frame portion 18 a
And is held in contact with the main surface (pressing and fixing surface). Reference numeral 25b indicates a silicon pad.

The back shield case 20 has an L-shape, a substantially concave cross-sectional shape, a main part formed by bending a metal plate, and a fitting hole formed in the outer side surface part 20a. 26, front shield case 19
The protrusion 27 protruding from the metal side surface 19b is fitted and connected and fixed. In the back shield case 20 connected and fixed to the front shield case 19 in this manner, the inner side surface portion 20b is disposed along the inner peripheral surface of the resin side surface portion 18b of the plastic frame 18, and the storage portion is provided on the back surface of the liquid crystal panel 13. Are formed, and the backlight unit 21 is stored in this storage section. Further, the angle θ between the bottom surface portion 20c and the inner side surface portion 20b of the back shield case 20 is smaller than 90 °, more preferably, 80 ° to 89 °. That is, the bending angle of the inner side surface portion 20b with respect to the bottom surface portion 20c of the back shield case 20 is set to an acute angle smaller than 90 °, and after the back shield case 20 is bent,
Even if the bending deformation returns due to springback, the bottom 2
The angle between 0c and the inner side surface portion 20b is set not to exceed 90 °. In this manner, the gap 28 is provided between the inner side surface 20b and the edge of the back shield case 20 and the backlight unit 21 housed in the housing.
Exists.

X-TAB16, Y-TAB17,
And X- connected to the liquid crystal panel 13 through these
The PCB 14 and the Y-PCB 15 are both housed in the gap between the front and back shield cases and the plastic frame 18. In addition, X-TA
The B16 and the X-PCB 14 are housed in the shield case and the gap on the long side of the plastic frame 18, and
-TAB17 and Y-PCB15 are accommodated in the gap on the short side.

Further, the contact between the X-PCB 14 and the front shield case 19 is prevented, and the external joint causes a solder joint between the X-PCB 14 and the X-TAB 16 and a difference between the liquid crystal panel 13 and the X-TAB 16. To prevent the isotropic conductive film (ACF) junction from breaking,
-The lower end of the PCB 14 is engaged and caught by a claw portion 29 formed to project from the bottom of the back shield case 20 into these storage spaces. Y-TAB17 and Y-
The same applies to the Y-PCB 15 connected via the TAB 17, and the lower end of the Y-PCB 15 is engaged with the claw portion of the back shield case 20.

In the liquid crystal display device of the embodiment configured as described above, the angle between the bottom surface 20c and the inner side surface 20b of the back shield case 20 is an acute angle smaller than 90 °. Inner side surface part 2 of 20
0b, the edge, and the backlight unit 21 housed in the housing on the back of the liquid crystal panel 13, an appropriate gap 2
8, the backlight unit 21 comes into contact with the edge of the inner side surface portion 20b of the back shield case 20 when the backlight unit 21 is stored or removed for replacement. , Will not be scraped. In addition, even after the backlight unit 21 is stored and fixed, no dust is generated due to contact with the back shield case 20.

[0022]

As is apparent from the above description, according to the light transmission type liquid crystal display device of the present invention, contact between the backlight unit and the metal shield case is prevented, and dust is generated due to the scraping of the backlight unit. And high quality display can be realized.

[Brief description of the drawings]

1A and 1B show an active matrix type liquid crystal display device according to an embodiment of the present invention, in which FIG. 1A is a perspective view showing a schematic configuration on the front side of a display panel, and FIG. FIG.

FIG. 2 is an exploded perspective view of the active matrix type liquid crystal display device of the embodiment.

FIG. 3 is a cross-sectional view of the liquid crystal display device shown in FIG. 2 taken along line BB.

FIG. 4 is a schematic perspective view of a conventional active matrix type liquid crystal display device.

FIG. 5 is a cross-sectional view along the line AA in the liquid crystal display device of FIG.

[Explanation of symbols]

 13 Liquid crystal panel 14 X-PCB 15 Y-PCB 16 X-TAB 17 Y-TAB 18 Plastic frame 19 ... front shield case 20 ... back shield case 20a ... outer side surface 20b ... inner side surface 20c ... bottom surface 21 ... backlight unit 28 ... gap

Claims (3)

[Claims] A light-transmitting display panel having a light modulation layer sandwiched between a pair of transparent substrates; a driving circuit for driving the display panel; and a connection between the display panel and the display panel and the driving circuit. A resin frame for stably holding, a metal frame whose main part is formed by bending a metal plate, and a metal frame for housing the display panel and the resin frame, respectively, and lighting means housed and arranged on the back surface of the display panel. A light-transmitting display device in which the drive circuit is held in a direction substantially perpendicular to the display surface of the display panel, wherein the lighting device extends to a storage space in which the lighting device is stored. A light-transmitting display device, wherein a gap exists between the metal frame and an edge of an inner side surface portion. 2. An angle between a bottom surface parallel to a display surface of the display panel and an inner side surface extending to a storage space of the illumination means in the metal frame, is an acute angle. The light transmission type display device according to claim 1, wherein 3. The light transmission type display device according to claim 2, wherein the angle between the bottom surface and the inner side surface of the metal frame is 80 ° to 89 °.