JPH1082987A - Liquid crystal display device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make a liquid crystal display device bright and small in plane external shape and to eliminate electrical problems, such as capacitor coupling, by arranging an L-shaped fluorescent lamp in the lower parts on the two sides arranged with a driver IC. SOLUTION: This liquid crystal display device has a structure obtd. by placing a main circuit board 4 on which signal receiving systems, control system circuits, etc., are mounted on the rear surface of a liquid crystal display panel block 3 and vertically arranging a sub-circuit board 5 coupled to the circuit board 4 by lead wires as a power supply circuit. The L-shaped fluorescent lamp 10 which is the light source of the liquid crystal display panel block 3 is supplied with a power source via the lead wires 13, 14 with a connector 11 from an inverter circuit mounted on the sub- circuit board 5. At this time, the L-shaped fluorescent lamp 10 is superposed sectionally on the liquid crystal panel driving IC in the lower parts on the two sides where the IC for driving of the X electrodes and Y electrodes of the liquid crystal panel 2 is arranged, thereby, the protrusion of a back light 8 from the external shape of the liquid crystal panel 2 is minimized and the plane external shape of the liquid crystal display panel block 3 is diminished. Further, the panel is made brighter by the increase in the total luminous fluxes.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a liquid crystal display device with a backlight. In particular, it relates to a television using the same.

[0002]

2. Description of the Related Art There are a direct type backlight and a sidelight type backlight for a liquid crystal display.

[0003] The structure of a liquid crystal display panel using a direct-type backlight or a sidelight-type backlight will be described below with reference to FIGS.

FIG. 8 shows the basic structure of a direct backlight. The light beam emitted from the fluorescent tube (22) is reflected directly or by the reflector (20), enters the diffuser (21), is diffused, and becomes a uniform surface light source.

FIG. 9 shows the basic principle of a sidelight type backlight. A light beam (23) emitted from a fluorescent tube (22) as a light source is distributed by a light guide plate (25) made of a transparent plastic and provided with a light distribution pattern (24) to become a surface light source. Direct fluorescent tube (26) 1 utilizing this basic principle
The conventional panel block (27) for this use is shown in FIGS.
It is. The light emitted from the direct fluorescent tube (26) is transmitted and distributed by the light guide plate (25), passes through the diffusion film (28), is collected by the light collecting film (29), and is collected by the liquid crystal panel (3).
0) is illuminated. Power is supplied to the direct fluorescent tube (26) from an inverter circuit (not shown) through a lead wire (3) with a connector.
Perform in 1).

[0006]

However, in the liquid crystal display device using the above-mentioned conventional backlight, in the direct type, a diffuser is used to obtain a uniform surface light source, and the highest luminance is obtained. When the distance between the fluorescent tube and the diffuser plate is short, the amount of luminous flux to be attenuated increases and the efficiency decreases, and the efficiency becomes low. In the direct fluorescent tube single lamp sidelight type shown in FIGS. 8 and 9, since the light flux incident on the light emitting area is small and the light is incident from one side of the rectangular light guide plate, the optical path length is required to transmit the light flux to all the light emitting areas. The longer the light flux is attenuated, the lower the efficiency and the darkness, and the need for a wiring area for the lead wires drawn out of the fluorescent tube increases the planar outer shape of the panel block and the width of the non-display area around the display area. Become, There is a problem that the stray capacitance is affected by lengthening the pressure lead wire, or that the luminous efficiency of the fluorescent tube is reduced due to capacitive coupling by wiring the GND lead wire near the fluorescent tube. Was.

Accordingly, an object of the present invention is to provide a liquid crystal display device which is bright, has a small planar outer shape, and has no electrical problems such as capacitive coupling.

[0008]

According to the present invention, there is provided a panel block including a panel on which driver ICs are arranged on two sides, and an L-shaped fluorescent tube for illuminating the panel and a backlight having a light guide plate. The present invention is characterized in that an L-shaped fluorescent tube is arranged below the two arranged sides. According to the above configuration, there is an effect that a bright and small panel block can be formed.

Further, a first lead wire connected to a first base of the L-shaped fluorescent tube is arranged along a side different from the two sides of the panel.

According to the above configuration, the width of the non-display portion of the panel block can be reduced, and there is an effect that a decrease in efficiency of the fluorescent tube can be prevented.

Further, a second lead wire connected to a second base of the L-shaped fluorescent tube and the first lead wire are overlapped around the second base and drawn out from the panel block. It is characterized by becoming.

According to the above construction, there is an effect that the planar outer shape of the panel block can be reduced, and interference between the high-voltage end of the fluorescent tube and the low-voltage lead can be prevented.

[0013]

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

(Embodiment 1) FIGS. 1, 2, 3, 4, and 5 are drawings showing an embodiment of a liquid crystal display device according to the present invention. To explain the configuration, a metal shield case A
(6), liquid crystal panel (2), plastic frame (7), backlight (8), shield case B (9)
A television (1) having a liquid crystal display panel block (3) as a display body is provided with a main circuit board (4) on which a receiving system, a control system circuit, and the like are mounted on the back of the liquid crystal display panel block (3). An L-shaped fluorescent tube (10), which is a light source of the liquid crystal display panel block (3), has a structure in which a sub-circuit board (5) connected to the board and a lead wire is used as a power supply circuit and is disposed at the lower left. Power is supplied from an inverter circuit (not shown) mounted in (5) via the lead wires 1, 2 (13) and (14) with the connector (11). At this time, an IC (12) for driving the X electrode and the Y electrode of the liquid crystal panel is disposed on the L-shaped fluorescent tube (10).
By overlapping the liquid crystal panel driving IC (12) in a cross section below the side, the protrusion of the backlight (8) from the outer shape of the liquid crystal panel (2) can be minimized, and the flat surface of the liquid crystal display panel block (3) can be suppressed. The external shape can be reduced. Further, since the fluorescent tube is L-shaped and the total luminous flux is increased, it can be made brighter than a conventional backlight using a single straight tube.

FIG. 6 is a diagram showing a main part of an embodiment of a liquid crystal display panel block according to the second aspect of the present invention. Lead wires 1 (13) are drawn from both ends of the L-shaped fluorescent tube (10) in a direction parallel to the long side of the L-shaped fluorescent tube (10) and toward the long side, and the lead wire 2 (14) is connected to the short side of the fluorescent tube. Are pulled out in the direction opposite to the terminal on the short side, and these terminals are combined into a connector (11) to improve product assemblability. In the above configuration, the long side end of the L-shaped fluorescent tube (10) close to the inverter circuit for driving the L-shaped fluorescent tube (10) is set to a high voltage, and connected by the shortest distance with the lead wire 2 (14). , A conductor (GN) adjacent to the lead wire 2 (14).
D), the luminous efficiency is increased, and the short side end (lead wire 1 (13)) far from the inverter circuit is not affected by performance. In this configuration, the lead wire 1 (13) is connected to the backlight light emitting portion (shaded portion in the drawing) (1).
5) A liquid crystal display panel is formed by wiring the L-shaped fluorescent tube (10) in a substantially rectangular shape using the space created by the protruding portion of the fluorescent tube non-light emitting portion (hatched portion in the figure) (16). The planar outer shape of the block (3) can be reduced. Further, the lead wire 1 (13) and the L-shaped fluorescent tube (1
0) do not overlap and the overlap between the lead wire 1 (13) and the lead wire 2 (14) is small, so that electrical interference such as capacitive coupling is suppressed, so that a decrease in the luminous efficiency of the fluorescent tube can be prevented.

FIG. 7 is a view showing a main part of an embodiment of the liquid crystal display panel block according to the third aspect of the present invention, around the high-voltage terminal portion of the fluorescent tube. The lead wire 1 (1
3) 2 and (14) are pulled out from the panel block to connect with the circuit. At this time, a hook (17) is integrally formed around the end of the fluorescent tube high-voltage portion of the frame (7), and the lead wire 2 is formed.
(14) is locked, and the lead wire 1 (13) is raised by the rib (19) provided on the frame so that the fluorescent tube terminal and the lead wire 1 (13) are overlapped in the cross-sectional direction so as to have a spatial distance. I pulled it out. With this configuration, the lead wire does not protrude outside the fluorescent tube terminal in a plan view, and the planar outer shape of the panel block can be reduced. Further, it is possible to prevent electrical problems such as sparks that may occur when the lead tube 1 (13) comes into contact with the terminal of the fluorescent tube high voltage unit.

[0017]

As described above, the liquid crystal display device of the present invention can be made bright by arranging the fluorescent tube of the backlight in an L-shape and arranging it on two sides of the driving IC of the liquid crystal panel. By laying out the lead wires of the fluorescent tube in the space created by the fluorescent tube non-light-emitting part of the backlight, and furthermore, drawing out the lead wires from the panel block in an overlapping manner around the fluorescent tube high-voltage part, and drawing out the liquid crystal display panel block. The size of the liquid crystal display device can be reduced by reducing the planar outer shape.

In addition, the fluorescent tube and the lead wire drawn out of the fluorescent tube can be wired so as not to interfere with each other, and the high-voltage side lead wire can be shortened to prevent a reduction in the luminous efficiency of the fluorescent tube. By providing wiring with a spatial distance to the fluorescent tube high voltage terminal, it is possible to prevent electrical problems such as sparks from occurring.

[Brief description of the drawings]

FIG. 1 is a diagram showing an outline of a liquid crystal television using the present invention.

FIG. 2 is a diagram showing a panel block structure of the present invention.

FIG. 3 is a detailed view showing an embodiment of the first embodiment.

FIG. 4 is a sectional view taken along line AA of FIG. 3;

FIG. 5 is a sectional view taken along line BB of FIG. 3;

FIG. 6 is a detailed view showing an embodiment according to claims 2 and 3;

FIG. 7 is a detailed view showing an embodiment according to claim 3;

FIG. 8 is a basic structural diagram of a direct backlight.

FIG. 9 is a diagram showing a basic principle of a sidelight type backlight.

FIG. 10 is a diagram showing a panel block using a conventional sidelight type backlight.

FIG. 11 is a diagram showing a relationship between a conventional panel block and a direct fluorescent tube.

[Explanation of symbols]

 1. LCD TV 2. Liquid crystal panel 3. Liquid crystal display panel block 4. Main circuit board 5. Sub circuit board 6. Shield case A7. Frame body 8. Backlight 9. Shield case B 10. L-shaped fluorescent tube 11. Connector 12. Liquid crystal panel drive IC 13. Lead wire 1 14. Lead wire 2 15. Backlight emitting section 16. Fluorescent tube non-light emitting section 17. Hook of frame 18. Rib of frame 19. Fluorescent tube of direct backlight 20. Reflector 21. Diffusion plate 22. Fluorescent tube 23. Luminous flux 24. Light distribution pattern of light guide plate 25. Light guide plate 26. Direct fluorescent tube 27. Conventional panel block 28. Diffusion film 29. Light collecting film 30. Liquid crystal panel 31. Lead wire with connector

Claims (3)

[Claims] 1. A panel block comprising a panel on which driver ICs are disposed on two sides, and a backlight having an L-shaped fluorescent tube for illuminating the panel and a light guide plate, wherein the driver IC is disposed. L at the bottom of two sides
A liquid crystal display device comprising a letter-shaped fluorescent tube. 2. The panel according to claim 1, wherein a first lead wire connected to a first base of the L-shaped fluorescent tube is arranged along a side different from the two sides of the panel. Liquid crystal display device. 3. A second lead wire connected to a second base of the L-shaped fluorescent tube and the first lead wire are overlapped around the second base and drawn out from the panel block. 3. The liquid crystal display device according to claim 2, wherein: