JP2000333190A - Color plane display device and heat liberation device of driver circuit-in color plane display device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a color plane display device with a thin profile and a light by improving a heat liberation characteristic. SOLUTION: Driver IC chips 36R, 36G, 36B that apply a voltage to a data electrode of a plasma address type liquid crystal display device are mounted on a driver board 32. One heat liberation member 60 that cools the driver IC chips is provided to the three driver IC chips that apply a drive voltage to three adjacent electrodes at least for three primary colors. The voltage applied to the three data electrodes for displaying one pixel is maximized when a single color is displayed, then the heat liberation member 60 with a heat liberation capacity when any of the three driver IC chips takes a maximum load is provided to the 3 driver IC chips so as to reduce the heat liberation capacity of the heat liberation member 60 in comparison with the case that one heat sink is provided to one driver IC chip. As a result, the plasma address type liquid crystal display device can be manufactured with a thin profile and a light weight.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a display device and a heat radiating device in the display device. The present invention particularly relates to a heat dissipation technology of a driver circuit in an active matrix type color flat panel display device such as a plasma addressed liquid crystal display device and a plasma display device, and more specifically, to such a color flat panel display device. The present invention relates to a heat radiator capable of reducing the thickness, weight, and cost, and a color flat panel display device having the heat radiator.

[0002]

2. Description of the Related Art There is a demand for a display device having a large display surface as a color flat display device capable of realizing a thin and flat large screen. As such a display device, recently, a plasma-addressed liquid crystal display device (PALC (Plasma
Addressed Liquid Crysta
1) Display devices), plasma display devices, and the like are receiving attention.

[0003] PALC is an example of a color flat panel display.
A display device is illustrated. The PALC display device uses a principle of applying a voltage for controlling liquid crystal by a switch using plasma discharge, and can realize a high-quality display device with a relatively simple structure. As a result, it is used as a large-screen color flat panel display.

FIG. 13 is a perspective view showing a sectional structure of a PALC display device. The PALC display device 1 includes a backlight 10, a polarizing plate 12, a plasma substrate 13, partition walls (ribs) 14, a thin glass plate (microsheet) 15, a liquid crystal layer 16, and a transparent electrode (ITO). Data electrode 18, a color filter 20, and a polarizing plate 22. In the color filter 20, three types of color filters of red (R), green (G), and blue (B) are arranged in a plurality of units as one unit that defines one pixel. A plurality of data electrodes 18 are formed at positions overlapping the color filters so as to face the color filters.

[0005] The plasma substrate 13 and the thin glass 15 are hollowly spaced by a partition 14 having a predetermined length, and a plurality of scanning grooves 24 are formed in the plasma substrate 13. An anode electrode 26 and a cathode electrode 28 are formed in pairs in the scanning grooves 24 so as to be parallel to each other. The scanning groove 24 forms a horizontal scanning line corresponding to an effective screen of the PALC display device 1.
The direction of the data electrode 18 is orthogonal to the directions of the anode electrode 26 and the cathode electrode 28.

The thin glass 15 in front of the partition wall 14 forms an insulating layer, and the thin glass 15 forms a scanning groove 2.
4 is sealed. Plasma substrate 13 and thin glass 1
5 is filled with a plasma gas, for example, a mixed rare gas such as helium.

A scan voltage of a negative pulse is applied to the cathode electrode 28 from a driver circuit (not shown), and a pair of the anode electrode 26 and the cathode electrode 28 is formed by a plasma pulse supplied at a predetermined timing. Between them, a plasma discharge occurs. As illustrated in FIG. 14, in the scanning groove 24, the plasma gas is ionized by the plasma discharge into plasma particles, and an electric conductor (plasma channel) is formed until the ionized plasma particles are completely extinguished. And performs the same operation as the switching element. This operation is called plasma switching.

In front of the thin glass 15, a liquid crystal layer 16 forming pixels in a matrix, a striped color filter 20 corresponding to the three primary colors of R, G, and B, and a stripe driving pixels of the liquid crystal layer 16. A data electrode 18 formed of a transparent electrode film is formed, and a front glass 21 is further disposed in front of the data electrode 18. The orientation of the data electrode 18 corresponding to R, G, B of the transparent electrode film is determined by the anode electrode 26 and the cathode electrode 2 in the scanning groove 24.
8, and the orthogonal portion (intersection) is one pixel. Color filter 20 of three primary colors (R, G, B)
By supplying a video signal for one horizontal line to each of the three data electrodes 18 overlapping with each other, and by sequentially discharging the plasma gas in the scanning grooves 24 in the vertical direction, the pixels of the pixels where the data electrodes 18 and the scanning grooves 24 intersect are formed. A video signal voltage is applied to the liquid crystal. The voltage is applied to the liquid crystal with reference to the potential of the anode electrode 26. The voltage (anode electrode voltage) _VA applied to the anode electrode 26 and the data electrode 1
8 part of the potential difference between the voltage (data electrode voltage) V _D applied is applied to the liquid crystal layer 16.

In order to avoid the application of a DC voltage to the liquid crystal which causes the burn-in phenomenon of the panel, the anode electrode voltage V
As illustrated the _A in FIG. 15, the polarity for each horizontal period for one and the voltage value for each horizontal period (voltage level) is a rectangular wave switching to high and low data electrode voltage V _D of the anode electrode voltage V _A Are inverted, and the direction D of applying the voltage to the liquid crystal is switched every horizontal cycle.

As described above, by controlling the voltage applied to the liquid crystal, the transmittance of the luminous flux emitted from the backlight 10 can be made different for each pixel to display a color image. That is, by controlling the transmission amount of light polarized by the liquid crystal layer 16 by the polarizing plates 12 and 22 arranged on the incident side and the emission side of the PALC display device 1,
Also in the LC display device 1, a color image can be displayed on the same principle as that of a normal TFT liquid crystal display device.

FIG. 16 is a diagram illustrating a driver module 30 provided around the data electrode 18 and having a driver IC chip for applying a drive voltage to the data electrode 18 in the PALC display device 1 illustrated in FIG. It is. A red driver I for applying a driving voltage to each of the R, G, and B display data electrodes 18 is provided on the driver substrate 32.
A plurality of sets of the C chip 36R, the driver IC chip 36G for green, and the driver IC chip 36B for blue are mounted. 1
Three driver IC chips 36 for applying a voltage to three adjacent R, G, B data electrodes 18 that define pixels.
R, 36G, at 36B, 1 pair, respectively, constitute one driver IC units 36 ₁ to 36 _6. In this specification, three driver IC chips 36 for one pixel are used.
One set of R, 36G, and 36B is called a driver IC unit. For example, one driver IC unit 36 ₁ in the driver IC chip 36R, 36G, data electrodes 18 for one pixel in 36B drives. Further, in this specification, a plurality of driver IC chips 36
A module on which R, 36G, and 36B are mounted is referred to as a driver module 30. Driver IC chip 3 for data electrode 18
6R, 36G, 36B are respectively connected to a plurality of corresponding data electrodes 18 via connection flexures 34.

When the output voltage of the driver IC chip changes, the voltage V _D applied to three adjacent data electrodes 18 changes, and an image is displayed on the PALC display device 1. The data electrode 18 which is a transparent electrode is called a data electrode because it serves to transmit a video data signal in this manner.

FIG. 17 is a perspective view of the driver module 30 illustrated in FIG. On the driver board 32, a plurality of sets of driver IC chips 36R, 36 for the data electrodes 18 are provided.
G, 36B are mounted. One finned heat radiating plate 44 is attached to each of the driver IC chips 36R, 36G, 36B via a heat conductive sheet 42. The heat conductive sheet 42 is the driver IC chip 36
R, 36G, and 36B are used to enhance the adhesion between the radiating plate 44 and the radiating fins. Each of the radiating plates 44 with radiating fins is provided with a driver IC chip 36R, 36G, 36.
B is designed to exhibit heat dissipation performance so that its driver IC chip is not damaged by its own heat generation even when each of the B's is in a maximum driving state, for example, a state of continuous operation at the maximum power.

In the large-sized PALC display device 1, a cooling fan is provided inside the PALC display device 1 in order to enhance the heat radiation performance of the driver IC chip and to suppress the temperature rise inside the PALC display device 1. A method of forcibly cooling the radiating plate 44 with radiating fins by wind from a fan and forcibly discharging hot air to the outside of the PALC display device 1 may be adopted.

FIGS. 18 (A) to 18 (C) show three pixels defining one pixel in the driver module 30 illustrated in FIG.
FIG. 6 is a diagram illustrating a heat radiation state when each of the driver IC chips 36R, 36G, and 36B is in a maximum load state. Driver IC chips 36R, 36G, 3
6B and the radiating plate 44 with radiating fins are provided in a one-to-one relationship. FIG. 18A shows a red driver IC indicated by oblique lines.
The chip 36R operates at the maximum load, and the other green driver IC chip 36G and blue driver IC chip 3
When no load is applied to 6B, the red driver IC chip 36
A large amount of heat is radiated from the radiating plate 44 with the radiating fin mounted on the R, and the radiating plate 4 with the fin mounted on the green driver IC chip 36G and the blue driver IC chip 36B.
This indicates that there is not much heat dissipation from the sample No. 4. FIG.
FIG. 18B shows a case where the green driver IC chip 36G indicated by oblique lines is operating at the maximum load, and FIG. 18C shows a case where the blue driver IC chip 36B indicated by oblique lines is operating at the maximum load. 18A, and heat radiation similar to the example illustrated in FIG. 18A is performed.

As described above, when one radiating plate with radiating fins 44 is provided independently for each one driver IC chip, one radiating plate with radiating fins 44 is the maximum of one driver IC chip. It is designed to have a heat dissipation capacity under load. Normally, the heat dissipation capacity of the heat dissipation plate 44 with heat dissipation fins is designed to be larger than the heat dissipation capacity of the driver IC chip at the maximum load. The heat dissipation capacity of the heat dissipation plate with the heat dissipation fins is basically defined by the surface area of the heat dissipation plate with the heat dissipation fins. In order to further increase the heat dissipation capacity, a method such as forced air cooling is applied.

[0017]

Since the PALC display device 1 has a large number of driver IC chips, it is difficult to use a heat radiating plate with heat fins having a large flat surface for the PALC display device 1 area. Therefore, as a method for securing the surface area of the radiator plate with the radiator fins, as illustrated in FIG. 17, the height of the radiator fins is increased or the number of the radiator fins is increased. Increasing the height of the radiating fins increases the depth of the PALC display device 1, so that
There is a problem that the weight increases, contrary to the reduction in thickness of the display device 1. Increasing the number of heat dissipating fins makes the heat dissipating plate with heat dissipating fins more complicated, which increases the price of the heat dissipating plate with heat dissipating fins, and eventually increases the overall price of the PALC display device 1. The above-mentioned problem becomes more remarkable as the size of the PALC display device 1 increases.

In the above example, a PALC display device is illustrated as a color flat display device. However, other color flat display devices similar to the PALC display device, such as a plasma display device, also encounter the above-described problems.

An object of the present invention is to provide a heat radiating device capable of reducing the thickness and weight of a color flat panel display device such as a PALC display device without deteriorating the heat radiation characteristics. Another object of the present invention is to provide a color flat panel display in which such a heat dissipation device is efficiently mounted.

[0020]

According to a first aspect of the present invention, at least a driver substrate for applying a voltage to at least three electrodes for displaying three primary colors for displaying an image on one pixel is mounted. A heat radiation device for a driver circuit in a color flat panel display device, wherein one heat radiation means is provided for each of the three driver IC chips.

An image in which the load on the driver IC increases most;
For example, even when displaying the full screen R, G, B single color,
The three R, G, and B driver ICs for one pixel do not simultaneously increase the load, and as shown in FIGS. 18A to 18C, the temperature of the driver IC chip becomes high. In consideration of the fact that there is only one, at least three driver IC chips for one pixel are collectively dissipated by one heat dissipating means.
It is smaller than the total heat dissipation capacity of the three heat dissipation means when one heat dissipation means is provided for each driver IC chip. The reduction in the heat dissipation capacity of the heat dissipation means means that the dimensions are smaller than the three heat dissipation means when one heat dissipation means is provided for each driver IC chip. As a result, the color flat panel display can be reduced in size and weight. For example, the heat dissipation capacity of the heat dissipation means is 3 when one heat dissipation means is provided for each driver IC chip.
It is about 2/3 or less of the total heat dissipation capacity of the individual heat dissipation means.

The heat dissipating means is a heat dissipating plate having a flat surface and an uneven surface on which heat dissipating fins are defined, and the flat surface of the heat dissipating means faces the driver IC chip.

Preferably, an elastic heat conductive elastic member having a predetermined thickness is interposed between the driver IC chip and the flat surface of the heat radiating means. As a result, the state of thermal contact between the driver IC chip and the radiator is improved.

Preferably, the heat dissipating means reduces the area of the flat surface of the heat dissipating means in accordance with the decrease in the heat dissipating capacity, and reduces the area of the at least three driver IC chips facing the heat dissipating means. Reduce the installation interval. As a result, the area of the color flat panel display can be reduced.

Preferably, the height of the radiating fins of the radiating means is reduced according to the decrease of the radiating capacity.
As a result, the color flat panel display can be made thin.

Preferably, the number of the radiating fins of the radiating means is reduced according to the reduction of the radiating capacity.
As a result, a low-cost and lightweight heat radiation means can be used.

[0027] More preferably, there is provided a refrigerant for cooling the radiator. Thereby, the heat radiation effect of the heat radiation means is promoted. As a result, the size of the heat radiating means can be further reduced.

Preferably, the refrigerant is a gas refrigerant for forcibly cooling the heat radiating means. By the forced cooling, the heat radiation effect of the heat radiation means is further promoted. As a result, the heat radiating means can be further downsized.

[0029] More preferably, the direction of the flow of the gaseous refrigerant and the direction of the radiating fins of the radiating means match or substantially match. As a result, the cooling effect by the refrigerant is further promoted.

More preferably, the heat dissipating means includes a heat dissipating plate having a flat surface, an uneven surface on which heat dissipating fins are defined, and a heat pipe for transmitting the temperature of the heat dissipating plate to the outside. The cooling effect becomes remarkable by the heat pipe.

According to a second aspect of the present invention, there is provided a color flat panel display device having the above-described heat radiating device. The color flat panel display of the present invention is thin and lightweight. Therefore, it is suitable for upsizing.

[0032]

DESCRIPTION OF THE PREFERRED EMBODIMENTS As an embodiment of a color flat panel display device and a heat radiator of a driver circuit in the color flat panel display device of the present invention, a plasma addressed liquid crystal display device (PALC display device) and a driver circuit in the PALC display device are described. An example of the heat radiating device will be described.

First Embodiment A first embodiment of the present invention will be described with reference to FIGS. FIG. 1 is a perspective view of a heat radiator of a driver circuit in a PALC display device according to a first embodiment of the present invention. The heat dissipation device of the driver circuit of the PALC display device illustrated in FIG. 1 corresponds to the heat dissipation device described with reference to FIG. 17, and is an enlarged view of the driver module 30 illustrated in FIG. In the driver module 30 described with reference to FIG. 17, one radiating plate 44 with radiating fins is provided for each driver IC chip. However, the driver module 30 according to the first embodiment of the present invention illustrated in FIG. In the driver module 30A, three driver IC chips 36R, 36R,
One heat radiation member 60 is provided for each of 6G and 36B.

The heat dissipation device of the driver circuit in the PALC display device illustrated in FIG. 1 is applied to the PALC display device described with reference to FIGS. Therefore, also in the first embodiment of the present invention, the PALC display device has the structure illustrated in FIG. 13 and performs the display operation described with reference to FIGS. Further, also in the present embodiment, the method of applying the voltage V _A applied to the anode electrode 26 and the voltage V _D applied to the data electrode 18 is basically performed by the method illustrated in FIG. Driver IC chips 36R, 36 for applying data electrode voltage V _D to data electrode 18
The operations of G and 36B themselves are the same as those described above.

In the driving method of the PALC display device illustrated in FIG. 13, the load on the driver IC chip is maximized when displaying a full-screen R, G, B monochromatic image. In the heat dissipation device of the driver circuit in the PALC display device illustrated in FIG. 1, it is necessary to satisfy an effective heat dissipation performance that does not cause thermal damage to the driver IC chip even when the maximum load state is continuous. At such a maximum load, three drivers I which supply the data electrode voltage V _D to the data electrode 18 of one pixel are provided.
Considering the operation of the C chips 36R, 36G, 36B,
It can be seen that the three driver IC chips 36R, 36G, 36B are not driven simultaneously. That is, the driver IC chip to become a high temperature the maximum load, three driver IC chips 36R for applying a data electrode voltage V _D to a single color display of the data electrode 18, 36G, which is one of the 36B. Therefore, the maximum load on the heat dissipation device of the driver circuit in the PALC display device is 3 in the case of the monochrome display.
It is only necessary that one of the driver IC chips 36R, 36G, 36B can effectively dissipate heat.

FIG. 2 shows the PA illustrated in FIGS.
Three driver IC chips 36 in LC display device 1
FIG. 3 is a diagram illustrating a connection state between R, 36G, and 36B and a data electrode 18. The outputs of the red driver IC chip 36R, the green driver IC chip 36G, and the blue driver IC chip 36B change according to the video signal, and the data electrodes 18
Data electrode voltage applied (potential) V _D is controlled to. At this time, the parasitic capacitance component 50 generated between the adjacent data electrodes 18 greatly affects the load of the driver IC chip for the data electrodes 18.

FIG. 3 is a diagram illustrating a connection state between the circuit of the driver IC chip 36G for green and the driver IC chip 36B for blue and the parasitic capacitance component 50 illustrated in FIG. A parasitic capacitance component 50 exists between any two adjacent data electrodes 18, for example, between the green data electrode 18G and the blue data electrode 18B.
Is green driver IC chip 36G and blue driver I
It becomes the load of the C chip 36B.

When an arbitrary same image is displayed in one horizontal synchronization and the next one horizontal synchronization, the voltage waveforms of the anode voltage and the driver IC output are those illustrated in FIGS. 4A to 4C. 4A to 4C, a symbol _VA indicates a voltage (potential) applied to the anode electrode 26, and a symbol _VDG indicates a data electrode applied to the G data electrode 18 from the green driver IC chip 36G. The symbol V _DB indicates a data electrode voltage (potential) applied to the B data electrode 18 from the blue driver IC chip 36B. According to the operation principle of the PALC display device 1 illustrated in FIGS. 13 and 14, the waveform of the anode electrode voltage _VA is a rectangular wave whose voltage level switches every horizontal synchronization. The waveform of the data electrode voltage (potential) V _D is, for example, the green data electrode 18.
V _DG (green driver IC chip 36G
Output voltage) and the waveform of the voltage V _DB (output voltage of the blue driver IC chip 36B) applied to the blue data electrode 18 in the “state 1” and the “state 2”. _The waveform has the absolute value of amplitude equal to that of _A and the polarity is inverted every horizontal cycle.

The waveforms of the potentials between the output terminals of the green driver IC chip 36G and the blue driver IC chip 36B in "state 1" and "state 2" of FIGS. 4A to 4C are shown in FIGS. The waveform illustrated in FIG. "State 1"
And the state 2, the green data electrode 18G
Capacitance component 50 between the blue data electrode 18B and the blue data electrode 18B
Charge direction is reversed. The difference in potential between the electrodes of the parasitic capacitance component 50 is a high voltage V _H and the low voltage V _L, V _H -
_VL . When displaying video data, “state 1” and “state 2” are alternately repeated. Therefore, the potential difference between the adjacent data electrodes is equal to the parasitic capacitance component 50.
, And the parasitic capacitance component 5
0 is green driver IC chip 36G, blue driver IC
It acts as a load for the tip 36B. The load on the driver IC chips 36R, 36G, and 36B is maximized during the display of R, G, and B monochromatic video images or the like in which the potential difference between the data electrodes is maximized.

A case where a full-screen G (green) monochromatic image is displayed, which is one of the conditions for maximizing the load on the driver IC, will be described with reference to FIGS. 7A to 7C. FIG. 7A shows a circuit connection state similar to that of FIG. 2, and FIG. 7B shows a data electrode voltage (potential) V _D at the time of displaying an image in any one horizontal synchronization.
Shows the waveform, FIG. 7 (C) shows the waveform of the next horizontal synchronization of the image display when the data electrode voltage (potential) V _D. FIG.
(B), continues to be displayed green monochrome picture by alternately repeated illustrated data electrode voltage V _D is the (C).

When the adjacent electrode is viewed from the G electrode 18, the potential difference between the adjacent electrodes 18 becomes maximum in the state illustrated in FIGS. 7B and 7C. Therefore, the parasitic capacitance component 50 on both sides is the green driver IC chip 36.
The green driver I acts as a large load for G
The heat generated by the C chip 36G becomes very large. For example,
When the adjacent electrode is viewed from the R electrode 18, the G electrode has a large potential difference with respect to the R electrode, but the B electrode has the same potential.
When the adjacent electrode is viewed from the electrode for B, G
The electrode for R has a large potential difference, but the electrode for R has the same potential. As a result, the load of the driver IC chip 36R for red and the driver IC chip 36B for blue due to the parasitic capacitance component 50 at this time is almost half of that of the driver IC chip 36G for green. Heat generation of the blue driver IC chip 36B is smaller than heat generation of the green driver IC chip 36G.

The above is the principle of the load generation by the parasitic capacitance component 50 generated between the data electrodes which occupies most of the load components of the driver IC. Due to this load, the driver IC is used to display R, G, B monochrome images, etc.
Although the total load increases, the loads on the three driver IC chips 36R, 36G, and 36B do not increase at the same time.

Therefore, as illustrated in FIG. 1, a plurality of sets of driver IC chips 36R, 36G, and 36B mounted on the driver board 32 have a red data electrode and a green data electrode used for displaying one pixel of video. Driver IC chips 36 for supplying a voltage to the blue data electrode
One heat dissipating member (heat sink) 60 is provided for each of R, 36G, and 36B via a heat conductive sheet 62. When one of the three driver IC chips 36R, 36G, and 36B becomes high in temperature, the temperature is increased as shown in FIGS. 8A to 8C. Dissipated from 60. The shaded portions of the driver IC chips 36R, 36G, and 36B in FIGS. 8A to 8C correspond to the corresponding data electrodes 18 for monochrome display.
And supplies the data electrode voltage V _D to indicate a state of being heated to a high temperature. In this specification, the driver board 3
2 sets of driver IC chips 36R, 36 mounted on
6G, 36B, heat dissipating member 60, and heat conductive sheet 6
2 is collectively called a driver module 30A.

In the case of the full-screen single-color display, the load increase of the display color driver IC is about twice as much as the load increase of the other two colors of driver ICs due to the parasitic capacitance component 50 between the data electrodes. Therefore, the heat dissipating member 6 having a heat dissipating capacity approximately twice as large as that when one heat sink is used for one driver IC chip.
0, one driver IC chip 36R, 36
G and 36B can be dissipated. That is, the heat radiating member 60 is connected to the driver IC chip 36 illustrated in FIG.
One radiating plate with radiating fins 4 in the case where one radiating plate with radiating fins 44 is provided for each of R, 36G, 36B
However, considering the cooling of the three driver IC chips, the heat radiation plate with three heat radiation fins 4 is larger than the heat radiation capacity of the heat radiation plate 4.
4 is about 2/3 of the total heat dissipation capacity.

The heat radiating member 60 is made of aluminum, copper, or the like. Aluminum is desirable from the viewpoints of thermal conductivity, weight reduction, and workability. Also in the present embodiment,
Preferably, a heat dissipating member 60 made of aluminum was used.

From the upper surface of the driver IC chip,
When the heat is dissipated through the driver IC chip 36R,
It is desirable that the upper surfaces of the 6G and 36B and the lower surface (flat surface) of the heat radiating member 60 be completely in contact (contact). For this purpose, for example, the driver IC chips 36R, 36G,
It is desirable that the upper surface of 36B be completely flat and the lower surface of the heat dissipating member 60 be completely flat. However, it is difficult to completely flatten the facing surfaces of the two. Further, three driver IC chips 36R, 36
It is difficult to make the upper surfaces of the three driver IC chips 36R, 36G, 36B completely uniform in height according to the mounting situation of the G, 36B on the substrate 32. Therefore, in the present embodiment, as a preferred example, the heat conductive sheet 62 is interposed between the upper surface of the driver IC chip and the lower surface of the heat radiating member 60. The heat conductive sheet 62 functions as a heat transfer means for effectively transmitting heat from the driver IC chip to the heat radiating member 60, and the three driver IC chips 36R, 36
It functions as height adjustment means for compensating for unevenness in the height of the G and 36B and / or unevenness on the lower surface of the heat radiating member 60. The heat conductive sheet 62 has good thermal conductivity, and
It is desirable to be made of a resilient material of some thickness. As such a heat conductive sheet 62,
Sumitomo 3M double-sided adhesive type heat conductive sheet with a thickness of 0.25 mm, manufactured by Sumitomo 3M, No. 5510, thickness 0.4 to 0.4 mm
A 7.5 mm single-sided adhesive type heat conductive sheet, a non-adhesive type heat conductive sheet having a thickness of 1.02 to 5.08 mm, manufactured by Commerics Inc., A574, or the like can be used.

The three driver IC chips 36R, 36
The G and 36B and the heat radiating member 60 are thermally connected via a heat conductive sheet 62 using an adhesive. as a result,
The heat of the driver IC chip is effectively transmitted to the heat radiating member 60.

The heat conductive sheet 62 may be divided for each driver IC chip as shown in the figure, or one heat conductive sheet 62 having substantially the same area as the lower surface of the heat radiation member 60 may be divided into three driver IC chips. It may be used for an IC chip.

According to the present invention, the heat dissipating capacity of one heat dissipating member 60 for the three driver IC chips is reduced.
, In particular, to reduce the surface area of the heat radiating member 60. There are various methods for reducing the heat radiation surface area of the heat radiation member 60, for example, (1) a method of reducing the surface area of the heat radiation member 60 facing the driver IC chip, and (2) a method of reducing the radiation fin of the heat radiation member 60. (3) a method of combining the above (1) to (3), (5) a thermal conductivity higher than that of the finned radiating plate 44. Various methods such as a method of manufacturing the heat dissipating member 60 with a low-cost and low-priced material, preferably, a size smaller than the sum of three heat dissipating plates 44 with heat dissipating fins can be adopted.

When the method (1) is applied, the distance between the three driver IC chips 36R, 36G, 36B can be reduced, the size of the driver module 30A can be reduced, and the heat radiation of the driver circuit in the PALC display device can be achieved. The device can be miniaturized. According to the method (1), three driver IC chips 36R, 36G, and 36 when three heat radiating plates 44 with heat radiating fins made of the same material as the heat radiating member 60, for example, aluminum are used.
The area of the surface facing B can be reduced to about 1/2 or less. Even when the heat radiation capacity is designed with a margin, the area can be reduced to about 2/3 or less. As a result, the length in the length direction of the driver module 30A is reduced from about 1/2 to about 2/3.
Can be reduced to a degree. When such a method is applied, the heat dissipation device of the driver circuit in the PALC display device, and eventually, the weight of the PALC display device is reduced.

When the method (2) is applied, the number of radiating fins whose processing is complicated is reduced, so that the cost of the radiating member 60 is reduced.

When the method (3) is applied, the height of the heat radiating fins of the heat radiating member 60 is reduced, so that the PALC display device can be made thin, small, and lightweight. Further, the price of the PALC display device can be reduced.

When the method (4) is applied, the advantages described above are integrated.

If the method (5) is applied, the heat radiator of the driver circuit in the PALC display device, and eventually the PA
The cost of the LC display device can be reduced.

Modification of First Embodiment FIG. 9 is a diagram illustrating a modification of the first embodiment of the present invention. The heat radiating device of the driver circuit in the PALC display device illustrated in FIG. 9 is different from the heat radiating member 60 illustrated in FIG.
An example in which the temperatures of three driver IC chips 36R, 36G, and 36B are dissipated by using a heat dissipating member 70 having A to 70F is illustrated. Lower surface of heat radiation member 70 and driver IC
A heat conductive sheet 72 is interposed between the chips 36R, 36G, and 36B. In this example, the heat radiation member 70 is made of aluminum. Compared with the heat radiating member 60 illustrated in FIG. 1 and the heat radiating member 70 illustrated in FIG. 9, since the heat radiating member 70 has the six heat radiating fins 70A to 70F, the overall dimensions (three-dimensional dimensions) are provided. Although small, the overall surface area is large. That is, the heat radiation member 70
The heat radiating area is the driver IC chip 36R, 36
FIG. 1 shows the area of the heat dissipating member 70 on the surface facing G, 36B and the driver IC chips 36R, 36G, 36B.
Assuming that the plane area of the heat radiating member 60 illustrated in FIG. Therefore, the heat dissipation performance of the heat dissipation member 70 is higher than that of the heat dissipation member 60. As a result, the height of the plurality of radiating fins 70A to 70F of the radiating member 70 can be made lower than the height of the radiating fins 60A and 60B of the radiating member 60. Therefore, the PALC display device can be made thinner. In this modified embodiment, the other effects are the same as those described above.

Second Embodiment First Embodiment In the first embodiment described with reference to FIGS.
In order to further enhance the cooling effect (heat radiation effect) of the heat radiation members 60 and 70, the direction of the heat radiation fins provided on the heat radiation members 60 and 70 is changed to the direction of the flow of the refrigerant around the driver module 30A, for example, the flow of air. It is desirable to match with the direction of. The reason is that the air as an example of the refrigerant comes into more contact with the heat radiating members 60 and 70, and the heat radiating member 6
This is because the effect of eliminating heat from 0 and 70 is increased. The air as the refrigerant may be in the case of natural convection in the PALC display device or in the case of being forcedly cooled with a cooling fan.

FIG. 10 shows a first embodiment of the second embodiment of the present invention. In the heat dissipation device of the driver circuit in the PALC display device illustrated in FIG. 1, cooling fins at both ends of the heat dissipation member 60 illustrated in FIG. FIG. 6 is a diagram showing a case where the direction of air is matched with the flow A of air in the PALC display device. In FIG. 10, the flow A of the air and the directions of the fins 60 </ b> A and 60 </ b> B at both ends of the heat radiation member 60 match. As described above, the radiation fins 60A, 60A of the radiation member 60 are provided.
When the direction of B and the flow A of air match, the radiation fins 6
Since the contact area between 0A and 60B and the air increases, the heat radiation effect of the heat radiation member 60 by the air increases. As a result, the driver IC chip 36R,
The effect of dissipating the heat of 36G and 36B is improved. In this manner, the direction of the heat radiating fins 60A and 60B of the heat radiating member 60 is made to coincide with the direction of the air flow, so
Of the first embodiment can be made smaller than that of the first embodiment. As a method of reducing the heat radiation capacity of the heat radiation member 60, any one of the methods (1) to (5) described above can be employed.

The radiation fins 60A, 60B of the radiation member 60
As a method of matching the direction of the air flow with the direction A of the air flow, a method of determining the direction of the heat radiating member 60 so as to match the air flow A near the driver module 30A in the PALC display device, or a method of radiating the heat radiating member A method of adjusting the flow of air so as to match the direction of the radiation fins 60 can be applied. As the latter method, it is desirable to use a fan as the forced air cooling means to create a flow of air that matches the direction of the heat radiating member 60.

Second Embodiment FIG. 11 shows the direction of the plurality of radiating fins 70A to 70H of the radiating member 70 and the flow A of air in the PALC display device in the radiator of the driver circuit in the PALC display device illustrated in FIG. It is a figure which shows the 2nd form matched. The number of the plurality of radiating fins 70A to 70H of the radiating member 70 illustrated in FIG. 11 is different from the number of the radiating fins 70A to 70F of the radiating member 70 illustrated in FIG. Is appropriately set according to the heat radiation characteristics of the heat radiation member. The heat radiation member 70 is also made of aluminum.

In the second embodiment of the second embodiment, similarly to the first embodiment, in order to further enhance the cooling effect (radiation effect) of the radiation member 60, the direction of the radiation fins provided on the radiation member is changed around the driver module 30A. This is an example in which the direction of the flow of the refrigerant, for example, the direction of the flow of the air is matched to enhance the heat radiation effect. Also in the third embodiment, the air as an example of the refrigerant may be in the case of natural convection in the PALC display device, or may be in the case of forcible air cooling using a cooling fan.

The heat radiating member 60 illustrated in FIGS.
11 has eight heat radiating fins 70A to 70H, the heat radiating area of the heat radiating member 70 is smaller than that of the driver IC chip 36R,
Assuming that the plane area of the heat radiating member 70 facing the 36G and 36B is equal to the plane area of the heat radiating member 60 illustrated in FIG. 1 facing the driver IC chips 36R, 36G and 36B, The heat radiation performance of the heat radiation member 70 is high because it becomes large. Since a large number of radiating fins are air-cooled in addition to the high radiating performance of the radiating member 70,
The heat radiation performance of the heat radiation member 70 is further enhanced. Therefore, the height of the plurality of radiating fins 70A to 70H of the radiating member 70 can be sufficiently reduced. As a result, when air cooling is performed using the heat radiating member 70, the PALC display device can be made thinner, and the PALC display device can be reduced in weight.

By rotating the direction of the radiating fins 70A to 70H of the radiating member 70 illustrated in FIG. 11 by 90 degrees, the flow A of the air and the directions of the radiating fins 70A to 70H of the radiating member 70 can be matched. According to such a method, the length of the radiating fins 70A to 70H of the radiating member 70 is increased, the height can be reduced, and the reduction in thickness of the PALC display device can be further promoted. Further, the driver IC chip 36R,
Since the area of the flat surface on the lower surface of the heat radiating member 70 opposed to 36G and 36B can be reduced, the size of the driver module 30A can be reduced.

The second embodiment described with reference to the first and second embodiments has been described focusing on portions different from the first embodiment described above, but other portions are different from those of the first embodiment. The same is true. The second embodiment is also applicable to bare chip mounting and the like.

Third Embodiment The heat radiation of a plurality of driver IC chips 36R, 36G, 36B by one heat radiation member 60, 70 is described in the third embodiment.
Not limited to individual. Many driver IC chips 36R,
If 36G and 36B can be radiated by one radiating member, PAL
The area of the entire heat dissipating member of the C display device can be reduced, and the PALC display device can be made thinner.
The weight of the ALC display device can be reduced.

However, the driver IC chips 36R, 36R
If the number of G and 36B increases, it becomes difficult to make the heights uniform, so even if a heat conductive sheet is used, the upper surfaces of many driver IC chips 36R, 36G and 36B and the lower surface of the heat dissipating member are separated. It is difficult to achieve sufficient adhesion. Therefore, a large number of drivers I
When radiating heat from the C chips 36R, 36G, 36B, it is desirable to increase the thickness of the heat conductive sheet for height adjustment.

FIG. 12 shows a third embodiment of the present invention.
FIG. 11 is a diagram illustrating a heat radiator of a driver circuit in a PALC display device when one heat radiating member 80 is used for nine driver IC chips 36R, 36G, and 36B. A thick heat conductive medium 82 is interposed between the driver IC chips 36R, 36G, 36B and the heat radiating member 80 for height adjustment, and the driver IC chips 36R, 36G, 36B, the heat radiating member 80 and the adhesive are connected.

Driver IC for One Heat Dissipating Member 80
As the number of chips increases, the mechanical warpage of the driver substrate 32 and the driver IC chips 36R, 36G, 36B
Unevenness in mounting height, warpage of lower surface of heat dissipation member 80,
The driver IC chips 36R, 36R
There is a portion where the distance between the upper surfaces of the G and 36B and the lower surface of the heat radiating member 80 increases. Therefore, the heat conduction medium 82 eliminates the defective contact between the driver IC chips 36R, 36G, and 36B and the heat dissipation member 80.

For example, about 9 to 12 driver ICs
When the chip is dissipated by one heat dissipating member 80, the heat dissipating member 80 corresponds to the area of 9 to 12 heat dissipating members when one heat dissipating member is provided for each driver IC chip.
Was able to be reduced to about 1/2 to about 1/4.

FIG. 12 illustrates an example in which the direction of a large number of radiating fins of the heat radiating member 80 is orthogonal to the paper surface. Therefore, it is desirable that the flow of air as a refrigerant coincides with the direction of these radiating fins. Of course, the direction of the heat radiation fins of the heat radiation member 80 may be different from that illustrated in FIG. 12 and may be parallel to the plane of the paper as illustrated in FIG.

In practicing the present invention, various modifications can be made without being limited to the above-described embodiment.
For example, the shapes of the heat radiation members 60, 70, 80 are not limited to those illustrated. In order to enhance the heat radiation effect of the heat radiation members 60, 70, and 80, as described above, it is desirable to forcibly blow the air near the driver module 30 to the heat radiation member using a cooling fan or the like.
The forced cooling of the heat dissipating member can significantly reduce the area of the heat dissipating member.

The refrigerant for effectively cooling the heat radiating member is not limited to air, and various refrigerants can be used.
Further, the refrigerant is not limited to a gas, but may be a liquid. In this case, a method in which the liquid refrigerant directly contacts the heat radiating member to directly radiate heat, for example, a method in which a hole is formed in the heat radiating member and the liquid refrigerant passes through the hole can be used. Preferably, the heat radiating members 60, 7
It is also possible to connect a heat pipe to 0,80 to dissipate heat more quickly and effectively. When the size of a PALC display device is increased, a method of promoting heat radiation from a heat radiation member using a heat pipe in a limited space becomes very effective.

In the above embodiment, the heat dissipating member and
The case where the driver IC chips are brought into contact with a plurality of driver IC chips arranged in a row has been described as an example, but the driver IC chips may be arranged in a plurality of rows, a rectangular arrangement, or various other arrangement methods.

The driver board 32 on which such a plurality of driver IC chips and the heat radiating member are mounted is desirably disposed above the PALC display device 1 from the viewpoint of air convection. It is desirable to provide a hole through which high-temperature air is discharged. With such an arrangement, it is possible to prevent other circuits inside the PALC display device from being damaged or malfunction due to high temperature.

In the above embodiment, a PALC display device has been exemplified as a color flat display device. However, the present invention is not limited to a PALC display device, and other color flat display devices conforming to the same structure and operation principle as the PALC display device. The present invention can also be applied to a device, for example, a plasma display device.

[0075]

According to the present invention, it is possible to provide a heat radiation device for a driver circuit in a small, lightweight, and thin color flat panel display device.

According to the present invention, the color flat panel display device can be made thin by applying the heat radiating device of the driver circuit in the color flat panel display device to the color flat panel display device. That is, according to the present invention, the driver I
The heat radiating means for releasing heat generated in the C chip can be reduced in size, and the number of heat radiating means can be reduced, so that the color flat panel display device can be reduced in size, in particular, thin.

The thinness and miniaturization of the color flat panel display according to the present invention lead to the weight reduction of the color flat panel display.
The number of driver IC chips increases as the color flat panel display increases in size and definition. Therefore, as the color flat panel display becomes larger and has higher definition, the effect of the weight reduction according to the present invention becomes more remarkable.

According to the present invention, the heat sink of the driver IC can be reduced in weight. Since a large number of driver ICs are arranged for driving the panel, the weight reduction of the heat radiating plate leads to a large weight reduction of the entire color flat panel display device. The effect of weight reduction by this heat radiation method will be further increased with the future increase in size and definition of panels.

As a result of the above-described effects, according to the present invention, the price of the color flat panel display is reduced. That is,
According to the present invention, the heat dissipating means has a very simple structure, so that the price of the heat dissipating means alone decreases, and the number of heat dissipating means also decreases, so that the cost of the entire heat dissipating means decreases.

[Brief description of the drawings]

FIG. 1 is a PAL as a first embodiment of a heat radiator of a driver circuit in a color flat panel display according to the present invention.
It is a perspective view of the heat dissipation device of the driver circuit in C display device.

FIG. 2 is a sectional view of a heat radiator of a driver circuit in a PALC display device as a modification of the first embodiment of the heat radiator of the driver circuit in the color flat panel display device of the present invention.

FIGS. 3A to 3C are diagrams illustrating a state where heat is released from a heat radiating member when one of the driver IC chips illustrated in FIG. 1 has a high temperature. .

FIG. 4 is a view illustrating a direction of a radiating fin of a radiating member in a radiating device of a driver circuit in the PALC display device illustrated in FIGS. 1 and 2 and a driver I in the PALC display device;
It is the figure which illustrated the 1st relationship with the direction of the flow of the wind near C chip.

FIG. 5 is a view illustrating a direction of a radiation fin of a heat radiation member in a heat radiation device of a driver circuit in the PALC display device illustrated in FIGS. 1 and 2 and a driver I in the PALC display device;
It is the figure which illustrated the 2nd relation with the direction of the flow of the wind near C tip.

FIG. 6 is a diagram illustrating a heat radiator of a driver circuit in a PALC display device in a case where one heat radiating member is used for nine driver IC chips as a fifth embodiment of the present invention. .

FIGS. 7A to 7C illustrate a first embodiment of the present invention in which a full-screen green monochrome image is displayed, which is one of the conditions for maximizing the load on the driver IC. FIG. 7A is a diagram showing a circuit connection state, and FIG.
(B) is a waveform diagram of a data electrode voltage V _D at any one horizontal synchronization of the video display, FIG. 7 (C) is a waveform diagram of a data electrode voltage V _D at the next horizontal sync of the video display is there.

FIGS. 8A to 8C show three drivers I which define one pixel in the driver module illustrated in FIG. 1;
It is the figure which illustrated the heat radiation state at the time of each of C chip each being in the maximum load state.

FIG. 9 is a diagram illustrating a modification of the first embodiment of the present invention.

FIG. 10 is a view showing a first embodiment of the second embodiment of the present invention, in a heat dissipation device for a driver circuit in the PALC display device illustrated in FIG. 1; It is a figure which shows the case where the flow A of the air in a PALC display apparatus was made to correspond.

FIG. 11 shows a second embodiment of the second embodiment of the present invention. In the heat dissipation device of the driver circuit in the PALC display device illustrated in FIG. 9, the heat dissipation fins at both ends of the heat dissipation member illustrated in FIG. It is a figure showing the case where the direction and the flow A of the air in the PALC display device were matched.

FIG. 12 is a perspective view of a heat radiator of a driver circuit in a PALC display device according to a second embodiment of the third embodiment of the present invention.

FIG. 13 is a perspective view showing a cross-sectional structure of a PALC display device.

FIG. 14 is a diagram illustrating the operation principle of the PALC display device illustrated in FIG. 13;

Figure 15 is a waveform diagram of the voltage V _D applied to the voltage V _A and the data electrodes applied to the anode electrode of the PALC display apparatus illustrated in FIG. 13.

FIG. 16 is a diagram illustrating a driver module having a driver IC chip disposed around data electrodes and applying a drive voltage to the data electrodes in the PALC display device illustrated in FIG. 13;

FIG. 17 is a perspective view of the driver module illustrated in FIG. 16;

18 (A) to 18 (C) illustrate heat radiation states when each of the three driver IC chips defining one pixel in the driver module illustrated in FIG. 17 is in the maximum load state, respectively. FIG.

[Explanation of symbols]

Is applied to the 1 ... PALC display device 10 ... backlight 12 ... polarization plate 13 ... plasma substrate 14 .. partition 15 ... thin glass 16 ... liquid crystal layer 18 ... data electrodes V _D · data electrode voltage 20 ... applied to the color filter 21 ... voltage 28 ... cathode electrode V _K .. cathode electrode applied to the front glass 22 ... polarizing plate 24 ... scanning groove 26 .. the anode electrode V _a · anode electrode Driver voltage 32, 30A, driver module 32, driver board 34, connection flexible 36, driver IC unit 36R, red driver IC chip 36G, green driver IC chip 36B, blue driver IC chip 42 heat conduction sheet 44 heat dissipation plate with heat dissipation fins 50 parasitic capacitance components 60, 70, 80 heat dissipation member 6 2,72,82-.Heat conductive sheet (heat conductive medium)

Claims (18)

[Claims] At least one heat radiating means is provided for each of three driver IC chips mounted on a driver board for applying a voltage to three electrodes for displaying three primary colors for displaying an image on one pixel. The heat radiation device of the driver circuit in the color flat panel display device provided. 2. The heat dissipating means is a heat dissipating plate having a flat surface and an uneven surface on which heat dissipating fins are defined, wherein the flat surface of the heat dissipating means faces the driver IC chip. 2. A heat radiating device for a driver circuit in a color flat panel display device according to claim 1, wherein a resilient heat conductive elastic member having a predetermined thickness is interposed between said driver IC chip and said flat surface of said heat radiating means. . 3. The heat dissipating means is a heat dissipating plate having a flat surface and an uneven surface on which heat dissipating fins are defined, wherein the flat surface of the heat dissipating means faces the driver IC chip. 3. The heat dissipating means according to claim 2, wherein the flat surface area of the heat dissipating means is reduced in accordance with the decrease in the heat dissipating capacity, and the installation interval of the driver IC chip facing the heat dissipating means is reduced. Heat dissipation device for driver circuit in color flat panel display. 4. The heat dissipating means is a heat dissipating plate having a flat surface and an uneven surface on which heat dissipating fins are defined, wherein the flat surface of the heat dissipating means faces the driver IC chip. 3. The heat radiating device for a driver circuit in a color flat panel display device according to claim 2, wherein a height of said heat radiating fin of said heat radiating means is reduced in accordance with a decrease in said heat radiating capacity. 5. The heat dissipating means is a heat dissipating plate having a flat surface and an uneven surface on which heat dissipating fins are defined, wherein the flat surface of the heat dissipating means faces the driver IC chip. 3. The heat radiating device for a driver circuit in a color flat panel display device according to claim 2, wherein the number of said heat radiating fins of said heat radiating means is reduced in accordance with a decrease in said heat radiating capacity. 6. A radiator for a driver circuit in a color flat panel display according to claim 1, further comprising a refrigerant for cooling said radiator. 7. A radiator for a driver circuit in a color flat panel display according to claim 6, wherein said refrigerant is a gas refrigerant for forcibly cooling said radiator. 8. The heat dissipating means is a heat dissipating plate having a flat surface and an uneven surface on which heat dissipating fins are defined, wherein the flat surface of the heat dissipating means faces the driver IC chip. 8. The heat radiating device for a driver circuit in a color flat panel display device according to claim 7, wherein the direction of the flow of the gaseous refrigerant and the direction of the radiating fins of the heat radiating means coincide with each other. 9. The heat dissipating means includes a heat dissipating plate having a flat surface, an uneven surface on which heat dissipating fins are defined, and a heat pipe for transmitting the temperature of the heat dissipating plate to the outside. 2. A heat radiating device for a driver circuit in a color flat panel display device according to claim 1, wherein a flat surface of the means faces the driver IC chip. 10. At least for each of three driver IC chips mounted on a driver substrate for applying a voltage to three electrodes for displaying three primary colors for displaying an image on one pixel,
An active matrix type color flat panel display device having a heat dissipation device provided with one heat dissipation means. 11. The heat dissipating means is a heat dissipating plate having a flat surface and an uneven surface on which heat dissipating fins are defined, wherein the flat surface of the heat dissipating means faces the driver IC chip. 11. The color flat panel display according to claim 10, wherein an elastic heat conductive elastic member having a predetermined thickness is interposed between the driver IC chip and the flat surface of the heat radiating means. 12. The heat dissipating means is a heat dissipating plate having a flat surface and an uneven surface on which heat dissipating fins are defined, wherein the flat surface of the heat dissipating means faces the driver IC chip. 12. The heat dissipating means according to claim 11, wherein the flat surface area of the heat dissipating means is reduced in accordance with the decrease in the heat dissipating capacity, and the installation interval of the driver IC chip facing the heat dissipating means is reduced. Color flat panel display. 13. The heat dissipating means is a heat dissipating plate having a flat surface and an uneven surface on which heat dissipating fins are defined, wherein the flat surface of the heat dissipating means faces the driver IC chip. 12. The color flat panel display according to claim 11, wherein the height of the heat radiating fins of the heat radiating means is reduced as the heat radiating capacity decreases. 14. The heat dissipating means is a heat dissipating plate having a flat surface and an uneven surface on which heat dissipating fins are defined, wherein the flat surface of the heat dissipating means faces the driver IC chip. 12. The color flat panel display according to claim 11, wherein the number of the radiating fins of the radiating means is reduced in accordance with the reduction of the radiating capacity. 15. A color flat panel display according to claim 10, further comprising a refrigerant for cooling said heat radiating means. 16. A color flat panel display according to claim 15, wherein said refrigerant is a gas refrigerant for forcibly cooling said heat radiating means. 17. The heat dissipating means is a heat dissipating plate having a flat surface and an uneven surface on which heat dissipating fins are defined, wherein the flat surface of the heat dissipating means faces the driver IC chip. 17. The color flat panel display according to claim 16, wherein the direction of the flow of the gaseous refrigerant and the direction of the radiating fins of the radiating means are made to match or substantially match. 18. The heat dissipating means includes a heat dissipating plate having a flat surface, an uneven surface on which heat dissipating fins are defined, and a heat pipe for transmitting the temperature of the heat dissipating plate to the outside. 11. The color flat panel display according to claim 10, wherein a flat surface of the means faces the driver IC chip.