JPH0882798A - Display device with back light - Google Patents

Abstract

PURPOSE: To radiate heat occurring on electrodes of a linear light source smoothly. CONSTITUTION: In a back light 3 of this liquid crystal display device, base part 11 are provided on the electrodes 9 of a fluorescent tube 6, and clipping contact springs 12 are provided on positions corresponding to the base part 11 of a circuit printed board, and the electrodes 9 of the fluorescent tube 6 are connected electrically to and loaded on a circuit printed board 2 by the base part 11 and the clipping contact springs 12. In such a case, since heat radiation plates 14 are provided on the clipping contact springs 12, the heat occurring on the electrodes 9 of the fluorescent tube 6 are radiated through the base part 11, the clipping contact springs 12 and the heat radiation plates 14. Thus, the heat occurring on the electrodes 9 of the fluorescent tube 6 are radiated smoothly.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a display device with a backlight.

[0002]

2. Description of the Related Art For example, some liquid crystal display devices have a backlight on the back side of the liquid crystal display panel because the liquid crystal display panel itself does not have a self-luminous ability. 3A and 3B show such a conventional liquid crystal display device. In this liquid crystal display device, the case 1
The circuit board 2, the backlight 3, the liquid crystal display panel 4 and the like are housed in this order in this order and covered with the display plate 5. Although not shown in detail, the liquid crystal display panel 4 has a structure in which liquid crystal is sealed between two transparent substrates made of a glass substrate or a resin film, and a polarizing plate is attached to the outside. .

The backlight 3 includes two fluorescent tubes (linear light sources) 6 arranged in parallel, and a light diffusing plate (light diffusing layer) 7 provided above the fluorescent tubes 6 and having an upper surface serving as a light emitting surface. , And a reflection plate (reflector) (not shown) provided below the fluorescent tube 6. Lead wires 8 are connected to both ends of the fluorescent tube 6, and the fluorescent tubes 6 are electrically connected to the circuit board 2 through the lead wires 8. The reflection plate is for preventing light from leaking from the lower surface of the fluorescent tube 6, and is made of a white coating plate or the like. The light diffusing plate 7 is for diffusing the light emitted from the fluorescent tube 6 to make the brightness uniform, and is made of a translucent resin that is cloudy. Then, the light diffused by the light diffusing plate 7 is applied to the lower surface (back surface) of the liquid crystal display panel 4. The circuit board 2 drives the fluorescent tubes 6 and the like.

[0004]

However, in such a conventional liquid crystal display device, the electrode 9 of the fluorescent tube 6 is more likely to generate heat than the other parts of the fluorescent tube 6, and the generated heat is not smoothly dissipated. Therefore, it may be 40 to 50 ° C. higher than room temperature. Therefore, the electrode 9 of the fluorescent tube 6
Are close to the light diffusing plate 7 and the liquid crystal display panel 4, the light diffusing plate 7 and the liquid crystal display panel 4 are heated to cause display unevenness on the liquid crystal display panel 4, or the liquid crystal is white in extreme cases. However, there was a problem that it became unreadable. An object of the present invention is to provide a display device with a backlight that can smoothly dissipate heat generated by the electrodes of the fluorescent tube.

[0005]

The present invention is directed to a display panel, a light diffusion layer disposed on the back surface of the display panel, a linear light source having at least a pair of electrodes, and a reflector for reflecting the light of the linear light source. And a circuit board for driving the linear light source at least, wherein the electrodes of the linear light source are electrically connected to and attached to the circuit board by a connecting member, and the connecting member is a wire. The heat generated by the linear light source is transmitted to the outside air and released.

[0006]

According to the present invention, the electrode of the linear light source is electrically connected to and mounted on the circuit board by the connecting member, and the connecting member transmits the heat generated by the linear light source to the outside air to radiate the heat. The heat generated in the electrode of the linear light source is radiated through the connecting member, and the heat generated in the electrode of the linear light source can be smoothly radiated.

[0007]

1A and 1B show a liquid crystal display device to which an embodiment of the present invention is applied. In these figures, parts having the same names as those in FIGS. 3A and 3B are designated by the same reference numerals, and the description thereof will be appropriately omitted. In this liquid crystal display device, a base 11 is provided on the electrode 9 of the fluorescent tube 6 instead of the conventional lead wire 8 shown in FIGS. 3A and 3B, and a predetermined portion of the circuit board 2 corresponding to the base 11 is provided. Is provided with a clip-type contact spring (connection member) 12.
The clip-type contact spring 12 is made of a material such as a metal having excellent conductivity and thermal conductivity, and as shown in FIG. 2, two contact plates 13a and 13b facing each other have their lower ends at the substrate 13c.
And a rectangular heat dissipation plate 14 at one end of the substrate 13c.
Are integrally provided, and a predetermined portion of the board 13c is electrically connected to the circuit board 2. An inner partition wall 1a is provided inside the clip-type contact spring 12, and the liquid crystal display panel 4 and the like are housed inside the inner partition wall 1a. Further, an outer partition wall 1b is provided outside the clip-type contact spring 12, and a heat dissipation plate 14 is arranged outside the outer partition wall 1b. Then, the fluorescent tube 6 is inserted into the inner partition wall 1a, and both contact plates 1 of the clip-type contact spring 12 are inserted.
An electrode 9 of the fluorescent tube 6 is electrically connected to the circuit board 2 by mounting the base 11 in a state of being sandwiched between 3a and 13b.

Thus, the electrode 9 of the fluorescent tube 6 is electrically connected to and mounted on the circuit board 2 by the clip-type contact spring 12, and the clip-type contact spring 12 transfers the heat generated by the fluorescent tube 6 to the outside air. Therefore, the heat generated at the electrode 9 of the fluorescent tube 6 is radiated through the heat radiating plate 14 of the clip-type contact spring 12, and the heat generated at the electrode 9 of the fluorescent tube 6 can be smoothly radiated. it can. Therefore, it is possible to prevent the display unevenness from occurring in the liquid crystal display panel 4, and it is possible to prevent the liquid crystal from becoming white and incapable of displaying. Further, since the inner partition wall 1a is provided inside the clip-type contact spring 12, the heat generated at the electrode 9 of the fluorescent tube 6 is prevented from being dissipated to the inner partition wall 1a in which the liquid crystal display panel 4 and the like are housed. be able to. Furthermore, since the heat dissipation plate 14 is arranged outside the outer partition wall 1b,
The heat can be dissipated smoothly.

In the above embodiment, the heat dissipation plate 14 is attached to the contact plate 13 with respect to the base plate 13c of the clip type contact spring 12.
The contact plate 13 is provided on the side a, 13b (upper side in FIG. 2).
It may be provided on the opposite side of a and 13b (the lower side of FIG. 2). Further, in the above-described embodiment, the heat dissipation plate 14 is provided on the clip-type contact spring 12, but the invention is not limited to this, and a mesh-like one may be provided, for example. Further, although the straight fluorescent tube 6 is described in the above embodiment, the present invention is not limited to this, and for example, U
It may be a fluorescent tube of a letter tube.

[0010]

As described above, according to the present invention, the electrode of the linear light source is electrically connected to and mounted on the circuit board by the connecting member, and the connecting member heats the linear light source to the outside air. The heat generated in the electrode of the linear light source is radiated through the connecting member, and the heat generated in the electrode of the linear light source can be smoothly radiated.

[Brief description of drawings]

FIG. 1A is a sectional view of a liquid crystal display device to which an embodiment of the present invention is applied, and FIG. 1B is a sectional view taken along line BB thereof.

FIG. 2 is a perspective view showing a clip-type contact spring.

FIG. 3A is a sectional view of a conventional liquid crystal display device, and FIG.
Is a sectional view taken along the line BB.

[Explanation of symbols]

 3 Backlight 4 Liquid Crystal Display Panel 6 Fluorescent Tube (Linear Light Source) 7 Light Diffusing Plate (Light Diffusing Layer) 9 Electrode 11 Base 12 Clip-type Contact Spring (Connecting Member) 14 Heat Sink

Claims (3)

[Claims] 1. A display panel, a light diffusion layer disposed on the back surface of the display panel, a linear light source having at least a pair of electrodes, a reflector for reflecting the light of the linear light source, and at least the linear shape. A display device with a backlight, comprising a circuit board for driving a light source, wherein the electrodes of the linear light source are electrically connected to and attached to the circuit board by a connecting member, and the connecting member is the line. A display device with a backlight, which transmits heat generated by a linear light source to the outside air to radiate the heat. 2. The display device with a backlight according to claim 1, wherein the electrode portion of the linear light source covers a periphery of the electrode portion with a partition wall. 3. The display device with a backlight according to claim 1, wherein the connection member uses a clip-type contact spring.