JPH06194652A - Liquid crystal display device - Google Patents

Abstract

PURPOSE:To make the luminance of a screen high, to make an entire device thin in structure and small in size and to easily exchange a lamp. CONSTITUTION:As to a liquid crystal display device using a light transmission plate type backlight unit; a lamp unit and a backlight unit are held in a liquid crystal holder 7 so that the lamp unit may be arranged on the side face of the backlight unit, and IC chips for horizontal and vertical drivers 4b, 4b', 5a and 5a' are respectively mounted on one right-and-left edge part and one up-and-down edge part of a liquid crystal panel 1, and the IC chips are attached to a reverse position opposed to the lamp unit.

Description

Detailed Description of the Invention

[0001]

The present invention relates to a laptop personal computer,
The present invention relates to a transmissive liquid crystal display device such as a word processor and a liquid crystal television.

[0002]

2. Description of the Related Art A transmission type liquid crystal display device of this type used in a conventional liquid crystal television is shown in FIG.
The one using the direct reflection type backlight unit as shown in (b) or FIGS. 4 (a) and 4 (b) was the mainstream. First, in FIGS. 3A and 3B, a U-shaped fluorescent lamp is used for the backlight unit. Here, the upper and lower end edges of the glass plate 2 constituting the liquid crystal panel 1 are The horizontal driver IC chips 4a and 4b are TAB-mounted, and the vertical driver IC chips 5a and 5a 'are TAB-mounted on the left edge portion.
These IC chips 4a, 4b and 5a, 5a 'are connected to and fixed to the driver substrate 6 in a structure surrounding the liquid crystal holder 7. Inside the liquid crystal holder 7, a lamp unit 3 including a U-shaped fluorescent lamp 31, a reflection plate 32, a diffusion plate 33 and an inverter unit 34 is inserted from the right side. A lamp drive circuit is incorporated in the inverter unit 34 and is electrically connected to the U-shaped fluorescent lamp 31. When replacing the lamp, the fluorescent lamp 31 can be replaced while pulling out the lamp unit 3 in the direction of arrow A and taking out the entire unit.

In the liquid crystal display device having such a structure, the driver TAB has a bent structure so that the image frame around the display portion can be made small, but it is difficult to make the lamp 31 small in diameter because of the U-shape processing of the lamp 31, so that the lamp unit 3 is made smaller. Since it became thicker, the entire device was thicker. On the other hand, in FIGS. 4A and 4B, a straight tube fluorescent lamp 31 'is used as a lamp unit, and basically the same as the one using the U-shaped fluorescent lamp described above. It has a structure. Here, the horizontal driver IC chips 4a and 4b, the vertical driver IC chips 5a and 5b, and the driver substrate 6 are mounted on a plane with respect to the liquid crystal panel 1 to thin the entire device. In the case of the straight tube fluorescent lamp 31 ', the diameter of the lamp itself can be reduced, so that the lamp unit 3 can be made thin and the entire device can be made thin.

[0004]

However, in the conventional liquid crystal display device, there is a natural limit to making the entire device thinner and smaller and at the same time increasing the screen brightness. That is, with the above-mentioned conventional direct reflection type backlight unit, it is difficult to reduce the thickness, and when the lamp brightness is increased and the tube current of the lamp is increased, the heat generation of the lamp is also increased and the horizontal and vertical mounting is performed on the periphery of the display screen. Since the driver IC may be damaged, it is not easy to satisfy both requirements at the same time.

In view of the above point, the present invention provides a liquid crystal display device capable of increasing the screen brightness and simultaneously making the entire device thin and small.

[0006]

In order to solve the above-mentioned problems, according to the present invention, at least a straight tube type lamp and a lamp reflector having a structure for wrapping the lamp and reflecting the light of the lamp in one direction are integrated. A lamp unit, a light guide plate that allows the light of the lamp to enter from a side surface and be uniformly propagated and diffused over the entire display screen, and arranged on the back side of the light guide plate,
A reflector for reflecting light from the back surface of the light guide plate, a diffuser plate for diffusing light from the front surface of the light guide plate, and a diffused light from the diffuser plate having a directional characteristic that substantially matches the viewing angle characteristic of the liquid crystal panel. A light guide plate type backlight unit including a light collecting plate, a liquid crystal panel that constitutes a liquid crystal display screen, and a liquid crystal holder that holds the lamp unit, the backlight unit, and the liquid crystal panel in a predetermined positional relationship. In a liquid crystal display device, horizontal and vertical driver IC chips are mounted respectively on the upper, lower, left and right edges of the liquid crystal display screen, and the IC chips oppose the lamp unit. It is installed in the opposite position.

Further, according to the present invention, the lamp unit can be detachably attached to the liquid crystal holder.

[0008]

This makes it possible to reduce the thickness of the entire device, and in particular, the driver IC chip is arranged in the opposite position apart from the lamp unit, so that the driver IC is damaged even when the brightness of the screen is increased. There is no.

Further, since the lamp unit is detachably attached to the liquid crystal holder, the lamp can be easily replaced.

[0010]

FIG. 1 shows an embodiment of a liquid crystal display device of the present invention using a light guide plate type backlight. Here, the same parts as those of the conventional example shown in FIGS. 3 and 4 are denoted by the same reference numerals. Here, 1 is a glass plate 2 in which a TFT (thin film transistor) that constitutes a pixel, a RGB color filter, a black matrix between each pixel and a bus line to each pixel are provided, and a liquid crystal is sealed inside, as in the conventional example. , A driver board 6 on which horizontal and vertical driver IC chips 4b, 4b ', 5a, 5a' are mounted, respectively, and the liquid crystal panel is formed in a flat plate shape.
In particular, the horizontal driver IC chips 4b and 4b 'are arranged at the lower end portion of the glass plate 2, and the vertical driver IC chips 5a and 5a are arranged at the left end portion of the glass plate 2, respectively. It is electrically connected to the TFT pixel. Further, 3 is a lamp unit having a built-in straight tube type fluorescent lamp 31, and the lamp unit 3 is arranged on the side surface (the upper surface in the drawing) of the backlight unit 8. As shown in detail in FIGS. 2 (a) and 2 (b), the lamp unit 3 is held in a state in which a lamp reflector 32 encloses a straight tube fluorescent lamp 31 in a lamp holder 35, and as a safety device. Thermal fuse 36
a and 36a 'are built in. The lead wire of the lamp 31 has electrode terminals 37a, 37a provided outside the lamp holder via thermal fuses 36a, 36a '.
It is electrically connected to ´.

The backlight unit 8 allows the light from the fluorescent lamp 31 to enter from the side surface and propagate uniformly over the entire display screen.
A light guide plate 9 for diffusing and arranged on the back side of the light guide plate 9,
A reflecting plate 10 for reflecting the light from the back surface of the light guide plate, a diffusing plate 11 for diffusing the light from the front surface of the light guiding plate, and a direction in which the diffused light from the diffusing plate 11 substantially matches the viewing angle characteristics of the liquid crystal panel 1. And a condenser plate 12 for condensing light with a characteristic, and these are arranged on the back surface of the glass plate 2 in a state of being laminated in a flat plate shape. And the liquid crystal panel 1 and the lamp unit 3
The backlight unit 8 is held by the liquid crystal holder 7. The light emitted from the fluorescent lamp 31 and the light reflected by the lamp reflector 32 are incident from the side surface of the light guide plate 9 of the backlight unit 8,
Light is uniformly propagated and diffused in the light guide plate 9, and light from the back surface of the light guide plate 9 is reflected by the reflection plate 10 and projected from the front surface of the light guide plate 9 to the liquid crystal panel 1 side. In this case, the light from the front surface of the light guide plate 9 is more evenly diffused by the diffusion plate 11, and is further condensed by the condensing plate 12 in the front direction of the liquid crystal panel 1. As a result, the light from the condenser plate 12 is condensed in the directional characteristic that substantially matches the viewing angle characteristic of the liquid crystal panel 1, and the front luminance is significantly increased. The fluorescent lamp 31 is integrated with the lamp reflector 32 and the like to form the lamp unit 3, and the lamp unit 3 is detachably attached to the liquid crystal holder 35. Therefore, if it becomes necessary to replace the lamp 31 due to its life or damage, the entire unit can be replaced so that even an amateur can easily replace the lamp.

[0012]

Since the liquid crystal display device of the present invention has a structure in which the fluorescent lamp is arranged on the side surface of the backlight unit, the overall thickness of the device can be reduced. Further, since the driver IC chip on the liquid crystal panel is arranged in the opposite position apart from the lamp unit, there is no possibility of damaging the driver IC even when the brightness of the screen is increased. Further, since the lamp unit is detachably attached to the liquid crystal holder, the lamp can be easily replaced.

[Brief description of drawings]

1A and 1B are respectively a front view and a side sectional view of an embodiment of a liquid crystal display device of the present invention.

2A and 2B are a front view and a side view of a lamp unit used in the same embodiment, respectively.

3A and 3B are a front view and a side sectional view of a conventional example of a liquid crystal display device.

4A and 4B are a front view and a side sectional view of another conventional example of a liquid crystal display device.

[Simple explanation of symbols]

 1 Liquid crystal panel 2 Glass plate 3 Lamp unit 4b, 4b 'Horizontal driver IC chip 5a, 5a' Vertical driver IC chip 6 Driver substrate 7 Liquid crystal holder 8 Backlight unit 9 Light guide plate 10 Reflector plate 11 Diffuser plate 12 Light collector plate 31 Fluorescent lamp 32 Lamp reflector 35 Lamp holder

Claims (3)

[Claims] 1. A lamp unit in which at least a straight tube type lamp and a lamp reflector which has a structure for wrapping the lamp and which reflects the light of the lamp in one direction are integrated, and the light of the lamp is incident from a side surface and displayed. A light guide plate for uniformly propagating and diffusing over the entire screen, a reflector plate arranged on the back side of the light guide plate for reflecting light from the back surface of the light guide plate, and a diffuser plate for diffusing light from the front surface of the light guide plate, A light guide plate type backlight unit including a light collecting plate that collects diffused light from the diffusing plate into a directional characteristic that substantially matches the viewing angle characteristics of the liquid crystal panel, a liquid crystal panel that constitutes a liquid crystal display screen, and the lamp unit. In a liquid crystal display device comprising a liquid crystal holder for holding the backlight unit and the liquid crystal panel in a predetermined positional relationship, one for each of the upper, lower, left and right sides of the liquid crystal display screen. Horizontal edge, be one that each mounting IC chip vertical drivers, and the liquid crystal display device the IC chip, characterized in that attached to the opposite position opposing the said lamp unit. 2. The liquid crystal display device according to claim 1, wherein the lamp unit is attached to an upper edge portion of a liquid crystal display screen, and the horizontal driver IC chip is attached to a lower edge portion of the liquid crystal display screen. 3. The liquid crystal display device according to claim 1, wherein the lamp unit is detachably attachable to a liquid crystal holder.