KR20070022549A - Electron emission display device and control method thereof - Google Patents

Abstract

An electron emission display device according to an embodiment of the present invention comprises a panel divided into an effective portion and an invalid portion, the plurality of electron emitting elements are provided in the effective portion; A data driver for applying a data signal to the panel; A scan driver for applying a scan signal to the panel; A power supply unit applying a first power source VS1, a second power source VS2, and a third power source VS3 to the data driver, the scan driver, and the anode electrode provided in the panel, respectively; A temperature sensor for measuring an exothermic state of the electron emission device provided in the panel; And a control unit configured to control the power supply unit through the measured temperature value provided from the temperature sensor so as to vary the power applied to the data driver, the scan driver, and the anode electrode, respectively.

Electron emission display device

Description

ELECTRONIC EMISSION DISPLAY DEVICE AND CONTROL METHOD THEREOF

1 is a block diagram illustrating an electron emission display device according to an exemplary embodiment of the present invention.

FIG. 2 is a cross-sectional view of a specific area of the panel employed in the electron emission display element shown in FIG. 1. FIG.

3 is a block diagram illustrating a part of an internal configuration of the controller illustrated in FIG. 1.

<Explanation of symbols for the main parts of the drawings>

100 panel 102: effective part

104: invalid part 110: an electron emitting device

112: dummy electron emitting device 200: data driver

300: scan driver 400: power supply

500: control unit 510: digital converter

600: temperature sensor

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electron emission display device, and more particularly, to an electron emission display device for controlling a voltage applied to a cathode / gate electrode and an anode electrode of each pixel in order to overcome the heat generation phenomenon of the electron emission display device. will be.

BACKGROUND ART A thin, lightweight flat panel display is used as a display device of a portable information terminal such as a personal computer, a cellular phone, a PDA, or a monitor of various information devices. Such flat panel displays include LCDs using liquid crystal panels, organic light emitting displays using organic light emitting diodes, and PDPs using plasma panels.

The flat panel display can be classified into a memory driving method and a non-memory driving method in terms of structurally divided into an active matrix and a passive matrix, and a light emission principle.

In general, the active matrix method has meaning with the memory driving method, and the passive matrix method has meaning with the non-memory driving method. The active matrix method and the memory driving method emit light at a period of a frame unit. The passive matrix method and the non-memory driving method emit a light at a period of a line unit.

As for the medium- and large-sized flat panel displays that are currently commercialized, TFT-LCD (Thin Film Transistor Liquid Crystal Display) is an active matrix method, and OLED, which is being developed as a new display device, is also an active method.

On the other hand, as a new display element, an electron emission display device is a passive matrix method, and unlike other flat panel devices, a non-memory driving method selects horizontal lines sequentially and emits light only when a selected one of the horizontal lines is selected. Apply the scan method. That is, the driving method has a constant duty ratio.

Such an electron emission display device includes an electron emission device for each pixel, and the electron emission device emits electrons from the cathode electrode in response to a voltage between the cathode electrode and the gate electrode. It is a device that is accelerated by the anode electrode and collides with a phosphor to operate in a manner of emitting light.

In general, the electron-emitting device has a method using a hot cathode and a cold cathode as an electron source, the electron emitting device using a cold cathode, FEA (Field Emitter Array) type, SCE (Surface Conduction Emitter) type , MIM (Metal-Insulator-Metal) type, MIS (Metal-Insulator-Semiconductor) type, BSE (Ballistic electron Surface Emitting) type and the like are known.

The FEA type electron emitting device uses a material having a low work function or a high function as an electron emission source to emit electrons by an electric field difference in vacuum, and has a sharp tip structure or carbon type. Devices that apply electron emission sources to materials or nanomaterials have been developed.

In addition, the SCE type electron emission device is a device in which an electron emission part is formed by providing a conductive thin film between two electrodes disposed to face each other on a substrate and providing a micro crack in the conductive thin film. The device utilizes a principle that electrons are emitted from the electron emission portion, which is the fine gap, by applying a voltage to an electrode to flow a current to the surface of the conductive thin film.

Also. The MIM and MIS electron emission devices each form an electron emission portion formed of a metal-dielectric layer-metal (MIM) and a metal-dielectric layer-semiconductor (MIS) structure, and are disposed between two metals or metals and semiconductors having a dielectric layer interposed therebetween. When a voltage is applied to the device, a device using the principle of emitting electrons while moving and accelerating from a metal having a high electron potential or a metal having a low electron potential toward the metal.

The BSE-type electron emitting device forms an electron supply layer made of a metal or a semiconductor on an ohmic electrode by using the principle that electrons travel without scattering when the size of the semiconductor is reduced to a dimension region smaller than the average free stroke of electrons in the semiconductor. And an insulating layer and a metal thin film formed on the electron supply layer to emit electrons by applying power to the ohmic electrode and the metal thin film.

In the conventional electron emission display device, the electron emission device included in each pixel emits electrons from the cathode electrode in response to the voltage between the cathode electrode and the gate electrode, and the emitted electrons are accelerated by the anode electrode. The light emitting device collides with the phosphor and emits light, and a heat generation phenomenon is caused by a voltage applied to the cathode / gate electrode and the anode electrode.

In particular, as the driving voltage applied to the electron emission display device increases recently, the heat generation phenomenon becomes more severe, and if the proper heat dissipation is not performed on the generated heat, not only the panel may be damaged but also the driving circuit may be damaged. It becomes possible.

The present invention is to overcome this problem, by measuring the temperature of the panel or drive circuit through a temperature sensor, and if the measured temperature is higher than the reference value, the control unit controls the power supply to the cathode / gate electrode and / in each pixel; Another object of the present invention is to provide an electron emission display device and a method of controlling the same, which reduce heat generation of a panel and reduce power consumption by adjusting a voltage applied to an anode electrode.

In addition, the present invention is provided with at least one dummy electron emission element in the non-effective portion of the panel, by measuring the current value through the dummy electron emission element to maintain the same emission current value when controlling the power supply unit Another object of the present invention is to provide an electron emission display device and a method of controlling the same, which maintain the same brightness and other characteristics even when the voltage applied to the pixel is varied.

In order to achieve the above object, an electron emission display device according to an exemplary embodiment of the present invention includes a panel divided into an effective part and an invalid part, and having a plurality of electron emission elements provided in the effective part; A data driver for applying a data signal to the panel; A scan driver for applying a scan signal to the panel; A power supply unit applying a first power source VS1, a second power source VS2, and a third power source VS3 to the data driver, the scan driver, and the anode electrode provided in the panel, respectively; A temperature sensor for measuring an exothermic state of the electron emission device provided in the panel; And a control unit configured to control the power supply unit through the measured temperature value provided from the temperature sensor so as to vary the power applied to the data driver, the scan driver, and the anode electrode, respectively.

Here, at least one dummy electron emission device may be further provided in an ineffective part of the panel, and the dummy electron emission device may be a device having the same cathode and anode characteristics as the electron emission device provided in the effective part of the panel. .

The temperature sensor may measure heat generated from the cathode electrode and / or the anode electrode of the electron emission device and provide it to the controller, and is provided on the upper and / or lower surface of the panel.

The control unit may further include a digital converter for converting a temperature measurement value provided from the temperature sensor into a digital value; A comparator for storing a digital value corresponding to the reference temperature in advance and comparing the digital value with the converted reference value; When the measured temperature value is higher than the reference temperature, it characterized in that it comprises a controller for controlling the power supply to vary the power provided to the data driver, the scan driver and the anode electrode, respectively.

In addition, the control unit measures a current value output from the dummy electron emission device provided in the invalid portion of the panel, and based on this the variable power supply value applied by the power supply to maintain the same emission current value It characterized by controlling the size of.

In addition, the electron emission display device control method according to an embodiment of the present invention comprises the steps of measuring the heat (temperature) generated in the panel; Converting the measured temperature into a digital value and comparing the measured temperature with a previously stored reference value; When the measured temperature is higher than the reference value, the step of varying the power supply (VS1, V2S, VS3) applied to the data driver, the gate driver and the anode electrode.

Here, the current value is measured through at least one dummy electron emission element 112 provided in at least one non-effective portion of the panel to control the size of the variable power source so that the electron emission elements maintain the same emission current value. Steps are further included.

In addition, the measured temperature is characterized in that the heat generated from the cathode electrode or the anode electrode of the electron-emitting device provided in the panel,

When it is determined that the temperature measured by the anode electrode exceeds the reference value, the first and second voltages VS1 and VS2 provided to the data driver and the scan driver are applied high, and the third voltage VS3 provided to the anode electrode. ) Is lowered, and when it is determined that the temperature measured by the cathode electrode exceeds the reference value, the third voltage VS3 provided to the anode electrode is applied high, and the data driver 200 and the scan driver 300 are applied. It characterized in that the first and second voltages (VS1, VS2) provided to the low.

In this case, the magnitudes of the variable first voltage VS1, the second voltage VS2, and the third voltage VS3 may be determined based on a current value measured by a dummy electron emission device provided in an invalid portion of the panel. The electron-emitting devices included in the effective portion of are controlled to maintain the same emission current value.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

1 is a block diagram illustrating an electron emission display device according to an exemplary embodiment of the present invention.

Referring to FIG. 1, an electron emission display device according to an exemplary embodiment of the present invention may include a panel 100 including a plurality of electron emission devices 110, a data driver 200, a scan driver 300, and a power supply 400. ) And a control unit 500, and further includes a temperature sensor 600 for checking the heating state of the panel.

The panel 100 is divided into an effective part 102 for displaying an image by a plurality of electron emission devices 110 and an ineffective part 104 located at an outer portion of the effective part and not contributing to image formation. .

In addition, the panel 100 includes n scan lines S1, S2,... Sn, m data lines D1, D2, ... Dm, and an anode electrode, and the scan lines S1, S2, ... Sn) and the data lines D1, D2, ... Dm are formed to cross each other.

In addition, the anode electrode may be formed over the entire area of the panel. However, this may be formed in the form of a plurality of stripes formed in a row direction similar to the scan lines, or may be formed in the form of a plurality of stripes formed in a column direction similar to the data lines, or may be formed in a mesh form.

Even when the anode electrode is formed in the form of a plurality of stripes or in the form of a mesh, the same voltage is generally applied to the entire anode electrode.

In addition, the electron emission element 110 serves as each pixel, which includes a cathode electrode, a gate electrode, and an anode electrode, and is located at an effective portion 102 of the panel, that is, an area where a scan line and a data line cross each other. Is formed.

In this case, any one of the scan line and the data line serves as the cathode electrode, and the other one of the scan line and the data line serves as the gate electrode.

In addition, the present invention is characterized in that at least one dummy electron emitting device 112 is provided in the ineffective area 104 of the panel 100, the current value is measured through the dummy electron emitting device 112 Accordingly, when the power supply unit 400 controls the power supply unit 400, the pixels maintain the same emission current value even though the power supply unit provides power to the electron emission element 110 provided in the effective unit 102 of the panel. The same luminance and other characteristics are maintained even when the voltage applied to the cathode / gate electrode and the anode electrode is varied.

The data driver 200 applies a data signal corresponding to the input image data DATA to the data lines D1, D2,..., Dm. In the present invention, a pulse width modulation (PWM) type data driver will be described. However, any data driver for adjusting the electron emission period of the electron emission device 110 in response to the input image data will be described. Included in the category.

In addition, the scan driver 300 sequentially applies a scan signal to the scan lines S1, S2,... Sn.

Preferably, the power supply unit 400 is configured of a switching mode power supply (SMPS), and a first power source VS1 and a second power source VS2 are respectively provided to the data driver 200, the scan driver 300, and the anode electrode. ) And a third power supply VS3.

In addition, the temperature sensor 600 may be provided on the upper and / or lower surface of the panel 100, and serves to measure the heating state of the electron emission device 110 provided in the panel 100. do.

Generally, the most severe heat generation in the panel 100 is a cathode electrode and an anode electrode of each electron emission element 110 provided in the effective portion 102, so that the temperature sensor 600 is the cathode electrode and the anode Measures the heat generated from the electrode and delivers it to the control unit 500.

The controller 500 receives an image signal and outputs a data signal corresponding thereto to the data driver 200, and applies a scan signal corresponding thereto to the scan driver 300.

In addition, the controller 500 converts the measured temperature value provided from the temperature sensor 600 to a digital value corresponding to a reference temperature by converting a digital value, and when the measured temperature value is higher than the reference temperature, the power supply unit ( The control unit 400 controls the data driver 200, the scan driver 300, and the first power source VS1, the second power source VS2, and the third power source VS3 respectively provided to the anode electrode.

That is, according to the present invention, the control unit 500 controls the power supply unit 400 to supply the data driver / scan driver and the anode electrode based on the result measured by the temperature sensor 600. When the measured temperature is higher than the reference temperature by comparing the measured temperature with the reference temperature, it is characterized in that the control to provide a variable.

In addition, the controller 500 measures the current value output from the dummy electron emission device 112 through the dummy electron emission device 112 provided in the ineffective region 104 of the panel 100, By appropriately controlling the voltage provided by the power supply unit 400 so that the electron emission devices 110 included in the effective unit 102 of the panel 100 maintain the same emission current value based on the measured value, The same luminance and other characteristics are maintained even if the voltage applied to each electron emission element is varied.

Here, the dummy electron emission device 112 is a device having the same cathode and anode characteristics as the electron emission device 110 provided in the effective portion 102, and is provided in at least one of the non-effective portions 104. .

1 illustrates a case where a total of four dummy electron emission devices 112 are provided at each corner of the panel 100, and the control unit 500 controls the four dummy electron emission. The current value is measured from the device 112 and the average value is taken. As described above, the average of the current values measured by the plurality of dummy electron emission devices 112 is compared with the reference current value, thereby reducing the error.

FIG. 2 is a cross-sectional view of a specific area of a panel employed in the electron emission display device illustrated in FIG. 1.

That is, this is a cross-sectional view of the electroluminescent element provided in the panel, which is only one embodiment, and the present invention is not limited to the electroluminescent element structure shown in FIG. 2.

Referring to FIG. 2, the panel includes an electron emission substrate 120 and an image forming substrate 130. In addition, the electronic device may further include a spacer 140 that maintains a constant gap between the electron emission substrate 120 and the image forming substrate 130.

The electron emission substrate 120 is a substrate that emits electrons in response to the voltage between the cathode electrode 122 and the gate electrode 124. The back substrate 121, the cathode electrode 122, the insulating layer 123, and the gate are provided. The electrode 124 and the electron emission part 125 are provided.

The back substrate 121 may be, for example, a glass or silicon substrate. When the back substrate 121 is formed by back exposure using a carbon nanotube (CNT) paste as the electron emission unit 125, a transparent substrate such as a glass substrate may be formed. desirable.

The cathode electrode 122 may be formed in a stripe shape on the rear substrate. The cathode electrode 122 is supplied with a data signal or a scan signal applied from the data driver or the scan driver. Accordingly, the cathode electrode 122 may be a conductor, and for the same reason as the back substrate 121, may be a transparent conductor such as indium tin oxide (ITO).

The insulating layer 123 is formed on the back substrate 121 and the cathode electrode 122, and electrically insulates the cathode electrode 122 from the gate electrode 124. The insulating layer 123 may be made of an insulating material, for example, PbO and SiO ₂ mixed glass.

The gate electrode 124 is disposed on the insulating layer 123 in a predetermined shape, for example, in a direction crossing the cathode electrode 122 on a stripe, and each data signal or scan signal applied from the data driver or the scan driver. Is supplied. The gate electrode 124 is made of a metal having good conductivity, such as at least one conductive metal material selected from gold (Au), silver (Ag), platinum (Pt), aluminum (Al), chromium (Cr), and alloys thereof. Can be. The insulating layer 123 and the gate electrode 124 have at least one first opening 126 at the intersection of the cathode electrode 122 and the gate electrode 124 so that the cathode electrode 122 is exposed.

The electron emission unit 125 is electrically connected to and positioned on the cathode electrode 122 exposed by the first opening 126, and includes a carbon nanotube; Nanotubes by graphite, diamond, diamond-like carbon or a combination thereof; Or a nanowire of Si or SiC.

The image forming substrate 130 is a substrate for forming an image by collision of electrons emitted from the electron emission substrate 120 to emit light. The image forming substrate 130 includes a front substrate 131, an anode electrode 132, a phosphor 133, and a light shielding film. 134 and a metal reflective film 135.

The front substrate 131 is preferably made of a transparent material such as glass so that light emitted from the phosphor 133 is transmitted to the outside.

The anode electrode 132 is preferably made of a transparent material such as an ITO electrode so that light emitted from the phosphor 133 is transmitted to the outside. The anode electrode 132 accelerates the electrons emitted from the electron emitting device even better. To this end, a high voltage positive voltage is applied to the anode electrode 132 to accelerate the electrons toward the phosphor 133.

The phosphor 133 emits light due to the collision of electrons emitted from the electron emission substrate 120, and is selectively disposed on the anode electrode 132 at random intervals. Examples of the G phosphor, that is, the phosphor that develops green color include, for example, ZnS: Cu, Zn ₂ SiO ₄ : Mn, ZnS: Cu + Zn ₂ SiO ₄ : Mn, Gd ₂ O ₂ S: Tb, Y ₃ Al ₅ O ₁₂ : Ce, ZnS: Cu, Al, Y ₂ O ₂ S: Tb, ZnO: Zn, ZnS: Cu, Al + In ₂ O ₃ , LaPO ₄ : Ce, Tb, BaO ㅇ 6Al ₂ O ₃ : Mn, (Zn, Cd) S: Ag, (Zn, Cd) S: Cu, Al, ZnS: Cu, Au, Al, Y ₃ (Al, Ga) ₂ O ₁₂ : Tb, Y ₂ SiO ₅ : Tb, or LaOCl: Tb Can be used. In addition, the B phosphor, i.e., a phosphor that develops blue color, may be, for example, ZnS: Ag, ZnS: Ag, Al, ZnS: Ag, Ga, Al, ZnS: Ag, Cu, Ga, Cl, ZnS: Ag + In ₂ O. ₃ , Ca ₂ B ₅ O ₉ Cl: Eu ²⁺ , (Sr, Ca, Ba, Mg) ₁₀ (PO ₄ ) ₆ Cl ₂ : Eu ²⁺ , Sr ₁₀ (PO ₄ ) ₆ C ₂ : Eu ²⁺ , BaMgAl ₁₆ O ₂₆ : Eu ²⁺ , CoO, Al ₂ O ₃ Added ZnS: Ag, ZnS: Ag or Ga may be used. Further, the R phosphor, i.e., the phosphor emitting red color, may be, for example, Y ₂ O ₂ S: Eu, Zn ₃ (PO ₄ ) ₂ : Mn, Y ₂ O ₃ : Eu, YVO ₄ : Eu, (Y, Gd) BO ₃ : Eu, --Zn ₃ (PO ₄ ) ₂ : Mn, (ZnCd) S: Ag, (ZnCd) S: Ag + In ₂ O ₃ , or Fe ₂ O ₃ added Y ₂ O ₂ S: Eu Can be used.

The light shielding film 134 is disposed at random intervals between the phosphors 133 to absorb and block external light and prevent optical crosstalk, thereby improving contrast ratio.

The metal reflective film is formed on the phosphor 133 to better focus electrons emitted from the electron emission substrate 120, and reflects light emitted from the phosphor 133 to the front substrate 131 by collision of electrons. To improve reflection efficiency. On the other hand, if the metal reflecting film serves as an anode electrode, the formation of the anode electrode 132 is optional and may be an unnecessary component.

3 is a block diagram illustrating a part of an internal configuration of the controller illustrated in FIG. 1.

However, the configuration of the controller 500 shown in FIG. 3 omits the description of the basic components of the controller provided in the general electron emission display device, and controls the power supply unit 400 for supplying the variable power source. Only the components are described.

That is, a component for receiving an image signal and outputting a data signal corresponding thereto to the data driver 200 and applying a scan signal corresponding thereto to the scan driver 300 will be omitted.

Referring to FIG. 3, the controller 500 includes a digital converter 510 for converting a temperature measurement provided from the temperature sensor 600 into a digital value; A comparator (520) for storing a digital value corresponding to the reference temperature in advance and comparing the digital value with the converted reference value; When the measured temperature value is higher than the reference temperature, the first power source VS1 and the second source which control the power supply unit 400 and provide the data driver 200, the scan driver 300, and the anode electrode ANODE, respectively. A controller 530 for varying the power supply VS2 and the third power supply VS3 is included.

In addition, the digital converter 510 receives a current measured through at least one dummy electron emission device (112 of FIG. 1) included in an invalid portion of the panel, and converts the current into a digital value, and thus the comparator 520. By comparing the converted digital value with a digital value corresponding to a pre-stored reference current value, when the controller 530 controls the power supply unit 400, each of the electron-emitting device of the panel refers to the reference Control to maintain the same emission current value corresponding to the current value.

Hereinafter, referring to FIGS. 1 and 3, a method of controlling an electron emission display device according to an exemplary embodiment of the present invention which adjusts a voltage applied to a cathode / gate electrode and an anode electrode of each pixel in order to overcome the heat generation phenomenon of the electron emission display device. To explain.

As described above, the most heat generating portion of the electron emission display device is a cathode / gate electrode and an anode electrode of each electron emission device 110 provided in the panel 100.

That is, a resistance exists in the cathode electrode region, and when a voltage is charged or discharged to the cathode, a large portion of the cathode is radiated by heat. In this case, the electron emission portion formed on the cathode electrode is formed. The problem is that it can cause damage.

In addition, when excessive current is generated due to excessive current generated in the anode electrode, there is a problem in that image quality is degraded due to deterioration of the phosphor formed on the surface of the anode electrode.

Accordingly, the present invention is provided with a temperature sensor 600 for measuring the heat generation generated in the panel 100, the panel 100 or a driving circuit, that is, the data driver 200 and / through the temperature sensor 600 Alternatively, when the temperature of the scan driver 300 is measured and the measured temperature is higher than the reference value, the controller 500 controls the power supply 400 to apply voltages VS1 and V2S to the data driver, the gate driver, and the anode electrode. By adjusting VS3), the heat generation phenomenon generated in the cathode / gate electrode and / or the anode electrode in each electron emission element 110 included in the panel is overcome.

In addition, at least one dummy electron emitting device 112 is provided at the ineffective part 104 of the panel 100, and the controller 500 measures the current value through the dummy electron emitting device 112. When the power supply unit 400 is controlled, each electron emission device 110 maintains the same emission current value, thereby maintaining the same brightness and other characteristics even when the voltage applied to the pixel, that is, the electron emission device 110 is varied. Keep it.

In more detail, when heat generation is generated in the cathode electrode as a result of the measurement by the temperature sensor 600, that is, when it is determined that the temperature measured by the cathode electrode exceeds the reference value, the controller of the controller 500 ( The 530 controls the power supply unit 400 to apply a high third voltage VS3 provided to the anode electrode, and the first and second voltages VS1 provided to the data driver 200 and the scan driver 300. , VS2) is applied low.

That is, since the amount of heat generated at each electrode is proportional to the square of the applied voltage, when the applied voltage is lowered, heat is also reduced and power consumption can be lowered accordingly.

However, in this case, since the emission current value generated in each electron emission element 110 must be kept constant, the variable voltages provided, that is, the first voltage VS1, the second voltage VS2, and the third voltage ( As described above, the size of VS3 is adjusted so that each electron emission device 110 maintains the same emission current value when controlling the power supply unit 400 through the current value measured by the dummy electron emission device 112 as described above. do.

On the other hand, when the heat sensor is generated as a result of the measurement by the temperature sensor 600, that is, when it is determined that the temperature measured by the anode electrode exceeds the reference value, the controller 530 of the control unit 500 is By controlling the power supply unit 400, the first and second voltages VS1 and VS2 provided to the data driver 200 and the scan driver 300 are high, and the third voltage VS3 provided to the anode electrode is applied. Apply low.

However, even in this case, since the emission current value generated in each electron emission element 110 must be kept constant, the variable voltages provided, that is, the first voltage VS1, the second voltage VS2, and the third voltage As described above, the size of VS3 is such that each electron emission element 110 maintains the same emission current value when the power supply unit 400 is controlled through the current value measured by the dummy electron emission element 112 as described above. Adjusted.

Here, the dummy electron emitting device 112 is a device having the same cathode and anode characteristics as the electron emitting device 110 provided in the effective portion 102, and may be provided with at least one, and according to the embodiment of FIG. In this case, a total of four dummy electron emitting devices 112 are provided at each corner of the panel 100. Accordingly, the controller 500 determines a current value from the four dummy electron emitting devices 112. Measure and take the average value. As described above, the average of the current values measured by the plurality of dummy electron emission devices 112 is compared with the reference current value, thereby reducing the error.

According to the present invention, by measuring the temperature of the panel or driving circuit, and by adjusting the voltage applied to the cathode / gate electrode and / or the anode electrode in each pixel based on this, it is possible to reduce the heat generation of the panel and lower the power consumption In addition, at least one dummy electron emission element may be provided in an ineffective part of the panel, and the current value may be maintained when the power supply unit is controlled by measuring a current value through the dummy electron emission element, thereby maintaining the same current value. Even if the applied voltage is varied, there is an advantage of maintaining the same brightness and other characteristics.

Claims (13)

A panel divided into an effective part and an invalid part, wherein the effective part includes a plurality of electron emission elements; A data driver for applying a data signal to the panel; A scan driver for applying a scan signal to the panel; A power supply unit applying a first power source VS1, a second power source VS2, and a third power source VS3 to the data driver, the scan driver, and the anode electrode provided in the panel, respectively; A temperature sensor for measuring an exothermic state of the electron emission device provided in the panel; And a control unit configured to control the power supply unit through the measured temperature value provided from the temperature sensor, and to vary the power applied to the data driver, the scan driver, and the anode electrode, respectively. The method of claim 1, And at least one dummy electron emission device is further provided at an ineffective portion of the panel. The method of claim 2, The dummy electron emission device is an electron emission device, characterized in that the electron emission element provided in the effective portion of the panel, the cathode and the anode having the same characteristics. The method of claim 1, And the temperature sensor measures heat generated from the cathode electrode and / or the anode electrode of the electron emission device and provides the heat to the controller. The method of claim 4, wherein And the temperature sensor is provided on an upper surface and / or a lower surface of the panel. The method of claim 1, The control unit includes a digital converter for converting a temperature measurement value provided from the temperature sensor into a digital value; A comparator for storing a digital value corresponding to the reference temperature in advance and comparing the digital value with the converted reference value; And a controller configured to control the power supply to vary the power provided to the data driver, the scan driver, and the anode electrode when the measured temperature value is higher than a reference temperature. The method of claim 1, The controller measures a current value output from a dummy electron emission device provided in an invalid portion of the panel, and based on this, the magnitude of a variable power supply value applied by the power supply unit to maintain the same emission current value. And an electron emission display device. Measuring heat (temperature) generated in the panel; Converting the measured temperature into a digital value and comparing the measured temperature with a previously stored reference value; And varying power (VS1, V2S, VS3) applied to the data driver, gate driver, and anode electrode when the measured temperature is higher than the reference value. The method of claim 8, Measuring the current value through the dummy electron emission element 112 provided at least one of the non-effective portion of the panel and controlling the size of the variable power source so that the electron emission element to maintain the same emission current value The method of claim 1, further comprising an electron emission display device. The method of claim 8, And the temperature measured is heat generated at a cathode electrode or an anode electrode of the electron emission device of the panel. The method of claim 10, When it is determined that the temperature measured by the anode electrode exceeds the reference value, the first and second voltages VS1 and VS2 provided to the data driver and the scan driver are applied high, and the third voltage VS3 provided to the anode electrode. A method of controlling an electron emission display device, characterized in that low) is applied. The method of claim 10, If it is determined that the temperature measured at the cathode electrode exceeds the reference value, The third voltage VS3 provided to the anode electrode is applied high, and the first and second voltages VS1 and VS2 provided to the data driver 200 and the scan driver 300 are applied low. Electronic emission display device control method. The method of claim 11 or 12, The magnitudes of the variable first voltage VS1, the second voltage VS2, and the third voltage VS3 may be determined based on a current value measured by a dummy electron emission device provided in an invalid portion of the panel. The electron emission display device control method according to claim 1, wherein the electron emission devices provided in the unit are controlled to maintain the same emission current value.

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