JP2002304150A - Plasma display unit - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a plasma display unit, capable of suppressing the amount of heat generation from a PDP(plasma display panel) according to the peripheral ambient temperature and heat generation from a power source circuit part. SOLUTION: In this plasma display device, a temperature sensor 6 detects the peripheral ambient temperature of the display device to output it as a temperature detection value S6. A temperature-to-voltage conversion circuit 7 converts the temperature detection value S6 into a voltage value, to output it as a temperature voltage value S7. A decision circuit 8 inputs the temperature voltage value S7 and reads out a peripheral ambient temperature, corresponding to the voltage value S7 and proper luminance, corresponding to the peripheral ambient temperature by referring to libraries recorded in a library recording part 10 and decides proper luminance to output it as luminance data S8. A luminance control circuit 9 generates a luminance control signal S9, and outputs it as the luminance data S8. Then, when the proper luminance expressed by the data S8 is high as to the luminance control signal S9, the number of sustaining discharge pulses is made to be increased, and when the proper luminance is low, the number of sustaining discharge pulses is made to be decreased.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a plasma display device having a plasma display panel (hereinafter, referred to as "PDP").

[0002]

2. Description of the Related Art FIG. 9 is a block diagram showing a configuration of a conventional plasma display device (Japanese Patent Laid-Open No. 10-232).
647). An output of the video signal processing circuit 101 is connected to each input of a white balance adjustment circuit 102 and a signal level detection circuit 111, respectively. An output of the white balance adjustment circuit 102 is connected to an input of the A / D conversion circuit 103. A / D conversion circuit 103
Is connected to the input of the PDP control circuit 104. An output of the PDP control circuit 104 is connected to an input of the PDP 105. An output of the PDP 105 is connected to an input of the temperature / voltage conversion circuit 108. The output of the temperature / voltage conversion circuit 108 is connected to each input of the difference circuit 107 and the temperature distribution calculation circuit 110, respectively. The output of the temperature / voltage conversion circuit 106 is supplied to the difference circuits 107 and 1
09 is connected to each input. Difference circuit 10
7 is connected to the input of the white balance adjustment circuit 102. The output of the temperature distribution calculation circuit 110 is connected to the input of the difference circuit 109. Difference circuit 109
Is connected to the input of the fan control circuit 112. An output of the signal level detection circuit 111 is connected to an input of the fan control circuit 112. Fan control circuit 11
The output of 2 is connected to the input of fan 113. The fan 113 cools the panel of the PDP 105, and in reality, a plurality of fans 113 are provided to face the panel of the PDP 105.

Next, the operation will be described. The video signal processing circuit 101 receives the decoded video signal S101 from outside. Then, based on the input decoded video signal S101, a primary color video signal S102 comprising R, G, B
Is generated and output. White balance adjustment circuit 102
Is the primary color video signal S1 from the video signal processing circuit 101.
Enter 02. Then, the input primary color video signal S1
02, and generates and outputs an analog video signal S103 that has been subjected to white balance adjustment. The A / D conversion circuit 103 receives the analog video signal S103 from the white balance adjustment circuit 102. Then, the input analog video signal S103 is A / D converted to generate and output a digital video signal S104 as digital data. The PDP control circuit 104 receives the digital video signal S104 from the A / D conversion circuit 103. Then, based on the input digital video signal S104, a PDP display signal S105 as pixel data is generated and output. The PDP 105 is a PDP control circuit 1
04, a PDP display signal S105 is input. And
A predetermined operation is performed based on the input PDP display signal S105, and an image is reproduced.

In the PDP 105, the surface temperature of the panel is measured, and a temperature measurement value S, which is the measurement result, is obtained.
106 is input to the temperature / voltage conversion circuit 108. The temperature / voltage conversion circuit 108 receives the input temperature measurement value S10
6 is converted to a voltage value and output as a temperature voltage value S107. On the other hand, the temperature / voltage conversion circuit 106 inputs a preset reference temperature S108 from outside. Then, the input reference temperature S108 is converted into a voltage value and output as a temperature voltage value S109. The difference circuit 107 calculates the temperature /
The temperature voltage value S109 is input from the voltage conversion circuit 106, and the temperature voltage value S109 is input from the temperature / voltage conversion circuit 108.
Enter 107. Then, a difference value between the two is obtained, and a white balance adjustment signal S110 corresponding to the difference value is generated and output. White balance adjustment circuit 102
Performs white balance adjustment on the primary color video signal S102 based on the white balance adjustment signal S110 input from the difference circuit 107.

The temperature distribution calculation circuit 110 receives a temperature voltage value S107 from the temperature / voltage conversion circuit 108. Then, based on the input temperature measurement value S107, PDP1
The temperature distribution of the panel surface 05 is obtained by calculation and output as a temperature distribution calculation value S111. The difference circuit 109 is
A temperature voltage value S109 is input from the temperature / voltage conversion circuit 106, and a temperature distribution calculation value S111 is input from the temperature distribution calculation circuit 110. Then, a difference value between the two is obtained, and a temperature control signal S112 corresponding to the difference value is generated and output.

The signal level detection circuit 111 receives the primary color video signal S102 from the video signal processing circuit 101. Then, a signal level is detected based on the input primary color video signal S102, and a signal level signal S113 as a detection result is generated and output. Fan control circuit 11
2 is a signal level signal S from the signal level detection circuit 111.
113 and the temperature control signal S112 from the difference circuit 109. Then, based on the input signal level signal S113 and temperature control signal S112, a fan control signal S114 is generated and output.
The fan 113 receives a fan control signal S114 from the fan control circuit 112. Then, based on the input fan control signal S114, the rotation speed is controlled so that the panel surface temperature of PDP 105 is kept constant. By keeping the panel surface temperature constant, P
White balance adjustment with little change in DP light emission luminance is realized.

[0007]

As described above, in the conventional plasma display device, the panel surface temperature of the PDP is measured, and based on the measurement result, white balance adjustment and fan rotation speed control are performed. I have. Therefore,
When the panel surface temperature of the PDP increases, the PDP can be cooled by increasing the rotation speed of the fan. However, the cooling effect of the fan is limited. The noise generated by the rotation of the motor increases. Therefore, there is a problem that heat generation from the PDP cannot be sufficiently suppressed only by controlling the rotation speed of the fan. The performance of the PDP is also affected by the temperature of the surrounding environment where the plasma display device is installed and the heat generated from the power supply circuit unit provided in the plasma display device. There is also a problem that control according to heat generation from the circuit unit is not performed.

The present invention has been made to solve such a problem, and provides a plasma display device capable of appropriately suppressing the amount of heat generated from a PDP in accordance with the ambient temperature and the heat generated from a power supply circuit. The purpose is to do so.

[0009]

Means for Solving the Problems Claim 1 of the present invention
A plasma display panel, a temperature detecting means for detecting the temperature of the surrounding environment, and a brightness for controlling the brightness of the plasma display panel based on the temperature of the surrounding environment detected by the temperature detecting means. Control means.

A plasma display device according to a second aspect of the present invention is the plasma display device according to the first aspect, wherein the plasma display device is detected by a fan for cooling the plasma display panel and a temperature detecting means. Further, a fan control means for controlling the fan based on the temperature of the surrounding environment is further provided.

According to another aspect of the present invention, there is provided a plasma display device, comprising: a plasma display panel; a power supply unit for supplying power to the plasma display panel; a radiator plate for radiating heat of the power supply unit; The temperature control device includes temperature detecting means for detecting the temperature of the heat sink, and brightness control means for controlling the brightness of the plasma display panel based on the temperature of the heat sink detected by the temperature detecting means.

A plasma display device according to a fourth aspect of the present invention is the plasma display device according to the third aspect, wherein the temperature is detected by a fan for cooling the plasma display panel and a temperature detecting means. Further, a fan control means for controlling the fan based on the temperature of the heat sink is further provided.

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiment 1 FIG. 1 is a block diagram showing a configuration of a plasma display device according to Embodiment 1 of the present invention. An output of the video signal processing circuit 1 is connected to an input of the white balance adjustment circuit 2. The output of the white balance adjustment circuit 2 is connected to the input of the A / D conversion circuit 3. The output of the A / D conversion circuit 3 is connected to the input of the PDP control circuit 4. PD
An output of the P control circuit 4 is connected to an input of the PDP 5. The output of the temperature sensor 6 is connected to the input of the temperature / voltage conversion circuit 7. The output of the temperature / voltage conversion circuit 7 is
It is connected to the input of the decision circuit 8. The output of the decision circuit 8 is connected to the input of the brightness control circuit 9. The output of the brightness control circuit 9 is connected to the input of the PDP control circuit 4. The library recording unit 10 is connected to the decision circuit 8.

The temperature sensor 6 measures the temperature of the surrounding environment of the plasma display device. Here, the “temperature of the surrounding environment” means a temperature around a place where the plasma display device is installed, for example, a temperature several cm away from the main body of the plasma display device. Temperature sensor 6
Are arranged around the plasma display device, and by taking an average value of them, the temperature of the surrounding environment can be accurately detected. The library recording unit 10 records a predetermined library (correspondence table) set in advance. The library describes a relationship among a voltage value, an ambient temperature corresponding to the voltage value, and an appropriate luminance of the PDP 5 corresponding to the ambient temperature (hereinafter referred to as “appropriate luminance”).

Next, the operation will be described. The video signal processing circuit 1 inputs the decoded video signal S1 from outside. Then, based on the input decoded video signal S1,
A primary color video signal S2 including R, G, and B is generated and output. The white balance adjustment circuit 2 receives the primary color video signal S2 from the video signal processing circuit 1. Then, based on the input primary color video signal S2, an analog video signal S3 subjected to white balance adjustment is generated and output. The A / D conversion circuit 3 receives the analog video signal S3 from the white balance adjustment circuit 2. Then, the input analog video signal S3 is A / D converted to generate and output a digital video signal S4 which is digital data.

The temperature sensor 6 detects the temperature of the surrounding environment of the plasma display device and outputs it as a detected temperature value S6. The temperature / voltage conversion circuit 7 receives the temperature detection value S6 from the temperature sensor 6. Then, the input temperature detection value S6 is converted into a voltage value and output as a temperature voltage value S7. The decision circuit 8 inputs the temperature voltage value S7 from the temperature / voltage conversion circuit 7. Then, with reference to the library recorded in the library recording unit 10, the temperature of the surrounding environment corresponding to the input temperature voltage value S7 and the appropriate brightness corresponding to the temperature of the surrounding environment are read, and the appropriate brightness is determined. And outputs it as luminance data S8.

The brightness control circuit 9 receives the brightness data S8 from the decision circuit 8. Then, the input luminance data S8
Based on the brightness control signal S related to the number of sustain discharge pulses.
9 is generated and output. Regarding the luminance control signal S9, the number of sustain discharge pulses is increased when the appropriate luminance represented by the luminance data S8 is high, and is decreased when the appropriate luminance is low.

The PDP control circuit 4 receives the digital video signal S4 from the A / D conversion circuit 3 and the brightness control signal S9 from the brightness control circuit 9. And
Based on the input digital video signal S4, a PDP display signal S5, which is pixel data, is generated and output. At this time, the PDP control circuit 4 receives the input luminance control signal S9
, The number of sustain discharge pulses is changed. PDP5
Receives the PDP display signal S5 from the PDP control circuit 4. Then, a predetermined operation is performed based on the input PDP display signal S5 to reproduce an image.

FIG. 2 is a graph showing the relationship between the ambient temperature and the appropriate luminance among the contents of the library recorded in the library recording section 10. The appropriate luminance decreases as the ambient temperature increases. The reason why the appropriate luminance is constant in a region where the surrounding environment temperature is equal to or lower than T1 is to prevent an increase in the amount of heat generated due to an excessively high luminance. Further, the reason why the appropriate luminance changes in a curve in the region of the temperature T1 or higher is to ease the sense of discomfort given to the viewer of the screen by making the degree of decrease in luminance gentle.

As described above, according to the plasma display device of the first embodiment, the brightness of PDP 5 is controlled by increasing or decreasing the number of sustain discharge pulses according to the temperature of the surrounding environment in which the plasma display device is installed. Therefore, the higher the ambient temperature, the lower the number of sustain discharge pulses
By lowering the brightness of DP5, the amount of heat generated from PDP5 can be suppressed.

Embodiment 2 FIG. FIG. 3 is a block diagram showing a configuration of a plasma display device according to Embodiment 2 of the present invention. The output of the decision circuit 8 is the fan control circuit 11
The output of the fan control circuit 11 is connected to the input of the fan 12. The fan 12 is for cooling the PDP 5 by blowing air, and a plurality of fans 12 are actually arranged facing the panel of the PDP 5.

The library recording unit 15 is connected to the decision circuit 8. The library recording unit 15 records a predetermined library set in advance. The library according to the second embodiment includes a voltage value, an ambient temperature corresponding to the voltage value, an appropriate luminance corresponding to the ambient temperature, and an appropriate rotation speed of the fan 12 corresponding to the ambient temperature. (Hereinafter referred to as “appropriate rotation speed”).

Other configurations of the plasma display device according to the second embodiment are the same as those of the plasma display device according to the first embodiment shown in FIG.

Next, the operation will be described. Decision circuit 8
Inputs the temperature voltage value S7 from the temperature / voltage conversion circuit 7. Then, with reference to the library recorded in the library recording unit 15, the temperature of the surrounding environment corresponding to the input temperature voltage value S7 and the appropriate luminance and appropriate rotation speed corresponding to the temperature of the surrounding environment are read out, An appropriate luminance is determined and output as luminance data S8, and an appropriate rotation speed is determined and output as rotation speed data S10.

The fan control circuit 11 receives the rotation speed data S10 from the decision circuit 8. Then, based on the input rotation speed data S10, a fan control signal S11 relating to the rotation speed of the fan 12 is generated and output. The fan 12 receives a fan control signal S1 from the fan control circuit 11.
Enter 1. Then, the input fan control signal S11
While changing the rotation speed based on the
Cool P5.

Other operations of the plasma display device according to the second embodiment are the same as those of the plasma display device according to the first embodiment shown in FIG.

FIG. 4 is a graph showing the relationship between the ambient temperature and the appropriate rotation speed in the contents of the library recorded in the library recording section 15. The appropriate rotation speed increases as the surrounding environment temperature increases.

As described above, according to the plasma display device according to the second embodiment, the rotation speed of fan 12 is controlled according to the temperature of the surrounding environment where the plasma display device is installed. Therefore, by increasing the rotation speed of the fan 12 when the temperature of the surrounding environment is high,
The cooling effect of the PDP 5 by the fan 12 can be enhanced.

Embodiment 3 FIG. 5 is a block diagram showing a configuration of a plasma display device according to Embodiment 3 of the present invention. An output of the video signal processing circuit 1 is connected to an input of the white balance adjustment circuit 2. The output of the white balance adjustment circuit 2 is connected to the input of the A / D conversion circuit 3. The output of the A / D conversion circuit 3 is PD
It is connected to the input of the P control circuit 4. An output of the PDP control circuit 4 is connected to an input of the PDP 5. The output of the temperature sensor 20 is connected to the input of the temperature / voltage conversion circuit 7. The output of the temperature / voltage conversion circuit 7 is connected to the input of the decision circuit 8. The output of the decision circuit 8 is connected to the input of the brightness control circuit 9. The output of the brightness control circuit 9 is connected to the input of the PDP control circuit 4. The library recording unit 21 is connected to the decision circuit 8.

The plasma display device according to the third embodiment includes a power supply circuit (not shown) for supplying drive power to the PDP 5 and other circuits, and a radiator plate (not shown) attached to the power supply circuit. Have. The heat radiating plate is for radiating heat of the power supply circuit unit. The temperature sensor 20 contacts the heat sink and detects the temperature of the heat sink itself. When a plurality of heat radiating plates are provided, the temperature of each heat radiating plate may be detected and an average value thereof may be obtained. In the library recording unit 21, a predetermined library set in advance is recorded. In the library according to the third embodiment, a relationship between a voltage value, a radiator plate temperature corresponding to the voltage value, and an appropriate luminance corresponding to the radiator plate temperature is described.

Next, the operation will be described. The video signal processing circuit 1 inputs the decoded video signal S1 from outside. Then, based on the input decoded video signal S1,
A primary color video signal S2 including R, G, and B is generated and output. The white balance adjustment circuit 2 receives the primary color video signal S2 from the video signal processing circuit 1. Then, based on the input primary color video signal S2, an analog video signal S3 subjected to white balance adjustment is generated and output. The A / D conversion circuit 3 receives the analog video signal S3 from the white balance adjustment circuit 2. Then, the input analog video signal S3 is A / D converted to generate and output a digital video signal S4 which is digital data.

The temperature sensor 20 detects the temperature of the radiator plate of the power supply circuit and outputs the detected temperature as a temperature detection value S20. The temperature / voltage conversion circuit 7 detects the temperature detection value S from the temperature sensor 20.
Enter 20. Then, the input temperature detection value S20 is converted into a voltage value and output as a temperature voltage value S21. The decision circuit 8 outputs the temperature / voltage value S2 from the temperature / voltage conversion circuit 7.
Enter 1. Then, referring to the library recorded in the library recording unit 21, the inputted temperature voltage value S
The temperature of the radiator plate corresponding to 21 and the appropriate luminance corresponding to the temperature of the radiator plate are read out, the appropriate luminance is determined, and output as luminance data S22.

The brightness control circuit 9 receives the brightness data S22 from the decision circuit 8. Then, the input luminance data S
22, a brightness control signal S23 related to the number of sustain discharge pulses is generated and output. Regarding the brightness control signal S23, the number of sustain discharge pulses is increased when the appropriate brightness represented by the brightness data S22 is high, and reduced when the appropriate brightness is low.

The PDP control circuit 4 receives the digital video signal S4 from the A / D conversion circuit 3 and the brightness control signal S23 from the brightness control circuit 9. Then, based on the input digital video signal S4, a PDP display signal S5 as pixel data is generated and output. At that time, the PDP control circuit 4 changes the number of sustain discharge pulses based on the input luminance control signal S23.
The PDP 5 receives a PDP display signal S5 from the PDP control circuit 4.
Enter Then, a predetermined operation is performed based on the input PDP display signal S5 to reproduce an image.

FIG. 6 is a graph showing the relationship between the heat sink temperature and the appropriate luminance among the contents of the library recorded in the library recording section 21. The appropriate luminance decreases as the heat sink temperature increases. The reason why the appropriate luminance is constant in the region where the heat sink temperature is equal to or lower than T2 is to prevent an increase in the amount of heat generated due to the luminance being too high, as in the first embodiment. Further, the reason why the appropriate luminance changes in a curve in the region of the temperature T2 or higher is that, similarly to the first embodiment, the degree of decrease in the luminance is moderated, thereby giving an uncomfortable feeling given to the viewer of the screen. This is to ease.

As described above, according to the plasma display device of the third embodiment, the number of sustain discharge pulses is increased or decreased in accordance with the temperature of the radiator plate attached to the power supply circuit of the plasma display device. Control brightness. Therefore, the higher the temperature of the heat sink, the lower the number of sustain discharge pulses and the lower the brightness of the PDP 5, thereby suppressing the amount of heat generated from the PDP 5.

Embodiment 4 FIG. FIG. 7 is a block diagram showing a configuration of a plasma display device according to Embodiment 4 of the present invention. The output of the decision circuit 8 is the fan control circuit 11
The output of the fan control circuit 11 is connected to the input of the fan 12.

A library recording unit 25 is connected to the decision circuit 8. The library recording unit 25 records a predetermined library set in advance. The library according to the fourth embodiment describes a relationship between a voltage value, a heat sink temperature corresponding to the voltage value, and an appropriate luminance and an appropriate rotation speed corresponding to the heat sink temperature.

Other structures of the plasma display device according to the fourth embodiment are the same as those of the plasma display device according to the third embodiment shown in FIG.

Next, the operation will be described. Decision circuit 8
Inputs the temperature voltage value S21 from the temperature / voltage conversion circuit 7. Then, with reference to the library recorded in the library recording unit 25, the radiator plate temperature corresponding to the input temperature voltage value S21 and the appropriate luminance and appropriate rotational speed corresponding to the radiator plate temperature are read, and the appropriate luminance is read. Is determined and output as luminance data S22, and an appropriate rotation speed is determined and output as rotation speed data S24.

The fan control circuit 11 receives the rotation speed data S24 from the decision circuit 8. Then, based on the input rotation speed data S24, a fan control signal S25 relating to the rotation speed of the fan 12 is generated and output. The fan 12 receives a fan control signal S2 from the fan control circuit 11.
Enter 5. Then, the input fan control signal S25
While changing the rotation speed based on the
Cool P5.

Other operations of the plasma display device according to the fourth embodiment are the same as those of the plasma display device according to the third embodiment shown in FIG.

FIG. 8 is a graph showing the relationship between the heat sink temperature and the proper rotation speed in the contents of the library recorded in the library recording section 25. The appropriate rotation speed increases as the heat sink temperature increases.

As described above, according to the plasma display device of the fourth embodiment, the rotation speed of fan 12 is controlled in accordance with the temperature of the radiator plate attached to the power supply circuit of the plasma display device. Therefore, when the temperature of the heat radiating plate is high, the cooling effect of the fan 12 on the PDP 5 can be enhanced by increasing the rotation speed of the fan 12.

[0045]

According to the first aspect of the present invention, the heat generation from the plasma display panel can be suppressed by lowering the brightness of the plasma display panel as the temperature of the surrounding environment increases. .

According to the second aspect of the present invention, the cooling effect of the plasma display panel by the fan can be enhanced by increasing the rotation speed of the fan as the temperature of the surrounding environment increases.

According to the third aspect of the present invention, the amount of heat generated from the plasma display panel can be suppressed by lowering the brightness of the plasma display panel as the temperature of the heat sink increases. .

According to the fourth aspect of the present invention, by increasing the rotation speed of the fan as the temperature of the heat sink increases, the cooling effect of the fan on the plasma display panel can be enhanced.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a configuration of a plasma display device according to a first embodiment of the present invention.

FIG. 2 is a graph showing a relationship between a surrounding environment temperature and appropriate luminance among contents of a library according to the first embodiment of the present invention.

FIG. 3 is a block diagram showing a configuration of a plasma display device according to a second embodiment of the present invention.

FIG. 4 is a graph showing a relationship between a surrounding environment temperature and an appropriate rotation speed among contents of a library according to the second embodiment of the present invention.

FIG. 5 is a block diagram showing a configuration of a plasma display device according to a third embodiment of the present invention.

FIG. 6 is a graph showing a relationship between a heat sink temperature and an appropriate luminance among contents of a library according to the third embodiment of the present invention.

FIG. 7 is a block diagram showing a configuration of a plasma display device according to a fourth embodiment of the present invention.

FIG. 8 is a graph showing a relationship between a heat sink temperature and an appropriate rotation speed among contents of a library according to the fourth embodiment of the present invention.

FIG. 9 is a block diagram showing a configuration of a conventional plasma display device.

[Explanation of symbols]

5 PDP, 6, 20 temperature sensor, 7 temperature / voltage conversion circuit, 8 decision circuit, 9 brightness control circuit, 10, 1
5, 21, 25 Library recording unit, 11 fan control circuit, 12 fans.

Claims (4)

[Claims] 1. A plasma display panel, temperature detecting means for detecting a temperature of a surrounding environment, and brightness of the plasma display panel is controlled based on the temperature of the surrounding environment detected by the temperature detecting means. A plasma display device comprising: a brightness control unit. 2. The apparatus according to claim 1, further comprising: a fan for cooling the plasma display panel; and a fan control unit for controlling the fan based on the temperature of the surrounding environment detected by the temperature detection unit. Item 2. The plasma display device according to item 1. 3. A plasma display panel, a power supply unit for supplying power to the plasma display panel, a radiator plate for radiating heat of the power supply unit, and a temperature detector for detecting a temperature of the radiator plate; A brightness control unit that controls brightness of the plasma display panel based on the temperature of the heat sink detected by the temperature detection unit. 4. The apparatus further comprising: a fan for cooling the plasma display panel; and fan control means for controlling the fan based on the temperature of the heat sink detected by the temperature detection means. Item 4. The plasma display device according to item 3.