JP2002156913A - Gas discharge type display device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a gas discharge type display device which has high display quality by suppressing the temperature of a display panel low with simple constitution and making the temperature difference in the panel surface small even when the panel luminance of a PDP is made high. SOLUTION: A heat-conductive sheet 2 is provided between the display panel 1 and a heat radiation plate 3 so as to be nearly in contact with the display panel 1 and heat radiation plate 3, and the heat-conductive sheet 2 is made of a sheet of 800 to 1,000 W/m deg.C in heat conductivity and 0.1 to 0.5 mm in thickness.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a gas discharge type display device having means for efficiently radiating heat generated in a display panel for displaying characters and images by utilizing gas discharge.

[0002]

2. Description of the Related Art In recent years, gas discharge type display devices (plasma display panels, hereinafter referred to as PDPs) have been used as flat display devices in information terminals such as portable computers, and have clear display and wide viewing angles. Its application field is expanding.

In PDPs, the higher the display brightness, the more
A large amount of heat is generated, the temperature of the display panel becomes high, and the display quality characteristics of the display panel deteriorate. Further, operating the display panel at a high temperature for a long time is not preferable in terms of performance and characteristics of the display panel. For example, this may reduce the reliability of a driver circuit for driving a display panel. Further, if a state in which there is a large temperature difference in the plane of the display panel continues for a long time, the glass constituting the display panel is distorted, which leads to breakage of the glass.

Accordingly, in order to lower the temperature of the display panel during operation and to reduce the distortion of the glass which may cause the glass breakage, the temperature difference within the display panel is reduced.
It is necessary to improve the performance and quality of the whole PDP.

[0005] As a countermeasure against this, a conventional PDP employs FIG.
As shown in an exploded perspective view and a sectional view of (a) and (b), a ventilation fan 22 is provided on a back surface of a display panel 21 by a spacer 23.
In this case, the temperature of the display panel 21 is lowered by blowing air to the display panel 21 through the intermediary.

[0006]

When the display panel surface is installed in parallel with the vertical direction and is turned on, the temperature distribution in the surface of the display panel 21 becomes as shown in FIG. 4 due to natural convection of heat. The difference in temperature between the high-temperature part and the low-temperature part occurs over ten degrees. Further, the temperature difference within the panel surface also increases depending on the image pattern displayed on the panel. For example, as shown in FIG. 5, when a bright background (dark display) continues for a long time on a dark background (dark display), the temperature difference between the bright region and the surrounding dark region becomes considerably large. If such a state continues for a long time, the glass constituting the display panel 21 is distorted, and the possibility that the display panel 21 is damaged is increased. In particular, if a temperature difference of 20 ° C. or more occurs in the plane of the display panel 21, the display panel 21 is likely to be damaged.

In the conventional gas discharge type display device provided with the ventilation fan 22, the temperature of the display panel 21 can be lowered, but it is difficult to reduce the temperature difference in the surface of the display panel 21. Was. Further, the noise of the motor of the ventilation fan 22 is disturbing, and electric power for driving the motor of the ventilation fan 22 is required.
There was a problem that the whole became large.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems. Even when the panel brightness of a PDP is increased, the temperature of the display panel can be kept low by a simple structure and the temperature difference in the panel surface can be reduced. An object of the present invention is to provide a gas discharge type display device which is small and has high display quality.

[0009]

In a gas discharge type display device according to the present invention, a heat conductive sheet is provided between a display panel and a radiator plate so as to be substantially in close contact with the display panel and the radiator plate; The heat conductive sheet has a heat conductivity of 800 to 10
It is constituted by a sheet of 00 W / m ° C and a thickness of 0.1 to 0.5 mm.

According to this configuration, the heat in the display panel surface during operation is conducted to the heat radiating plate through the heat conductive sheet and radiated into the air, thereby lowering the temperature in the display panel surface. The temperature difference in the display panel can be reduced. Further, it is possible to improve the adhesion between the heat conductive sheet and the display panel and the heat radiating plate by absorbing the warpage between the display panel and the heat radiating plate, and to reduce the external impact.

[0011]

(Embodiment 1) FIG. 1 (a),
(B) is an exploded perspective view (a) and a cross-sectional view (b) showing the gas discharge type display device according to the first embodiment of the present invention. The display panel 1 includes a heat conductive sheet 2 and a heat sink 3. I have. The protrusions 4 of the heat radiating plate 3 are for efficiently dissipating heat. The heat conductive sheet 2 reduces the in-plane temperature difference of the display panel 1 and more efficiently transfers the heat of the display panel 1 to the radiator plate 3 to radiate heat from the radiator plate 3 into the air, thereby reducing the temperature of the display panel 1. It acts to lower it. In addition, the use of a gel-like soft material as the heat conductive sheet 2 has an effect as a cushioning material, and has an effect of protecting the display panel 1 from external impact.

In the present embodiment, a 26-inch display panel is used, and a thickness of 1 mm to
A heat conductive sheet 2 made of a 5 mm gel-like silicon sheet and a heat radiating plate 3 made of aluminum are sequentially attached,
White display was performed over the entire display panel with a power of 120 W.
In this case, the temperature of the display panel was reduced by about 25 ° C. as compared with the case where nothing was attached. As the heat conductive sheet 2, a heat conductive sheet such as a rubber sheet can be used in addition to the silicon sheet.

(Embodiment 2) Since the display panel 1 and the radiator plate 3 are slightly warped, both of them are connected to the heat conductive sheet 2.
The heat conductive sheet 2 should have high flexibility in order to improve heat conductivity by protecting the display panel 1 from external impact. Also, reduce the temperature difference in the panel surface,
In order to enhance the effect of lowering the temperature of the panel, the heat conductivity of the heat conductive sheet 2 is preferably higher. However, when a material having a high thermal conductivity is used as the heat conductive sheet 2, the metal component in the material is high.
Poor flexibility. Therefore, as shown in the cross-sectional view of FIG. 2, the heat conductive sheet 2 is made flexible with a high heat conductive sheet (first heat conductive sheet) 6 such as a metal sheet or a carbon sheet having a high heat conductivity. It has a two-layer structure with a standard thermal conductive sheet (second thermal conductive sheet) 7 such as a rich gel-like silicon sheet. The high thermal conductive sheet 6 has a thickness of 0.1 to
The thickness is reduced to 0.5 mm to provide flexibility. The temperature difference in the display panel surface due to the heat generated in the display panel 1 is reduced by the high heat conductive sheet 6. The heat transmitted to the high heat conductive sheet 6 is efficiently transmitted to the heat radiating plate 3 by the standard heat conductive sheet 7, and is radiated from the heat radiating plate 3 to the air. In addition, since the heat conductive sheet 2 has elasticity, external vibrations and shocks are reduced and transmitted to the display panel 1 to enhance the effect of preventing the panel from being damaged, and the adhesion between the display panel 1 and the heat sink 3 is improved. And the efficiency of heat conduction is increased.

In this embodiment, the high thermal conductive sheet 6 is a high thermal conductive carbon sheet having a high thermal conductivity (a thermal conductivity of 800 to 1000 W / m ° C. and a thickness of 0.1 to 0.5 m).
m) as a standard heat conductive sheet 7 as a gel silicon sheet (thermal conductivity is 1 to 5 W / m ° C., thickness is 1 to 5 m
Using m), a pattern display of a central bright display and a peripheral dark display as shown in FIG. 5 was performed. At this time, the temperature distribution on the center XX line (see FIG. 5) of the display panel was as shown by the solid line 8 in the characteristic diagram of FIG. A broken line 9 in FIG. 6 indicates a temperature distribution on the center XX line (see FIG. 5) of the display panel when the pattern display as shown in FIG. 5 is performed in the gas discharge display device according to the first embodiment. Is shown. As shown in FIG. 6, in the characteristics of the display panel according to the present embodiment (solid line 8), the heat in the display panel surface is different from the characteristics of the display panel according to the first embodiment (dashed line 9) from the center to the end. The temperature difference within the display panel surface was significantly reduced. This is because the high thermal conductivity carbon sheet has a high thermal conductivity of 800 to
This is due to having a temperature of 1000 W / m ° C.
Further, the heat conductivity of the high thermal conductivity carbon sheet is lower in the thickness direction than in the direction of the sheet surface, but by making the thickness thinner as described above, heat is efficiently transmitted in the thickness direction.

In the first embodiment and the present embodiment,
According to FIG. 6, the temperature difference in the display panel surface is smaller than 20 ° C., and damage to the display panel can be avoided.

As the high thermal conductive sheet 6, a copper foil or an aluminum foil can be used in addition to the high thermal conductive carbon sheet. As the standard heat conductive sheet 7, a rubber sheet or the like can be used in addition to the silicon sheet.

[0017]

As described above, according to the present invention, a heat conductive sheet is provided between a display panel and a heat radiating plate so as to be substantially in close contact with the display panel and the heat radiating plate. By forming the conductive sheet from a sheet having a thickness of 0.1 to 0.5 mm, not only the temperature of the display panel during operation is reduced, but also the temperature difference in the display panel surface is reduced, and high reliability is achieved. It is possible to provide a display device. Further, since a ventilation fan is not used unlike the conventional case, there is no noise from the motor, and power for driving the motor and space for mounting the motor are not required.

[Brief description of the drawings]

FIG. 1A is an exploded perspective view of a gas discharge type display device according to a first embodiment of the present invention; FIG.

FIG. 2 is a sectional view of a gas discharge type display device according to a second embodiment of the present invention.

3A is an exploded perspective view of a conventional gas discharge type display device, and FIG.

FIG. 4 is a schematic diagram of a temperature distribution in a display panel surface due to natural convection of heat.

FIG. 5 is a display surface diagram showing a display pattern.

FIG. 6 is a temperature distribution characteristic diagram of the display panel of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Display panel 2 Heat conductive sheet 3 Heat sink 4 Projection 6 1st heat conductive sheet (high heat conductive sheet) 7 2nd heat conductive sheet (standard heat conductive sheet)

Continuation of the front page F term (reference) 5C040 GA10 GH10 KB11 KB29 MA02 MA13 5G435 AA12 AA16 AA18 BB06 GG44 HH18

Claims (2)

[Claims] 1. A heat conductive sheet is provided between a display panel and a heat sink so as to be substantially in close contact with the display panel and the heat sink, and the heat conductive sheet has a thickness of 0.1 to 0. .
A gas discharge type display device composed of a 5 mm sheet. 2. A heat conductive sheet is provided between a display panel and a heat sink so as to be substantially in close contact with the display panel and the heat sink, and the heat conductive sheet has a heat conductivity of 800 to
A gas discharge type display device comprising a sheet having a thickness of 1000 W / m ° C and a thickness of 0.1 to 0.5 mm.