KR20010100663A - Field Emission Display and Method of Driving the same - Google Patents

Abstract

The present invention relates to a field emission display device capable of increasing color purity and driving at low voltage.

The field emission display device of the present invention has the same color of adjacent phosphors between pixel cells.

According to the field emission display device of the present invention, the color purity can be improved by arranging the phosphors so that the colors of the sub pixels are the same. In addition, since the AC voltage is applied only to the anode electrodes formed on the two phosphors at the same time, color purity can be improved and power consumption can be minimized.

Description

Field emission display device and driving method thereof {Field Emission Display and Method of Driving the same}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a field emission display device and a driving method thereof, and more particularly, to a field emission display device and a driving method thereof which are driven at a low voltage while increasing color purity.

Recently, various flat panel displays have been developed to reduce weight and volume, which are disadvantages of cathode ray tubes (CRTs). Such flat panel displays include liquid crystal displays (hereinafter referred to as "LCD"), field emission displays (hereinafter referred to as "FED"), and plasma display panels (hereinafter referred to as "PDP"). And electroluminescence (hereinafter referred to as "EL"). In order to improve the display quality, research and development have been actively conducted to increase the brightness, contrast and color purity of flat panel displays.

The FED concentrates a high field on a sharp cathode (emitter), emits electrons by a quantum mechanical tunnel effect, and displays an image by exciting the phosphor using the emitted electrons.

1 and 2, an FED having an upper glass substrate 2 on which an anode electrode 4 and a phosphor 6 are stacked, and a field emission array 32 formed on the lower glass substrate 8. Is shown. The field emission array 32 includes the cathode electrode 10 and the resistive layer 12 formed on the lower glass substrate 8, and the gate insulating layer 14 and the emitter 22 formed on the resistive layer 12. ) And a gate electrode 16 formed on the gate insulating layer 14. The cathode electrode 10 supplies a current to the emitter 22, and the resistive layer 12 limits the overcurrent applied from the cathode electrode 10 toward the emitter 22, thereby making it uniform to the emitter 22. It serves to supply current. The gate insulating layer 14 insulates between the cathode electrode 10 and the gate electrode 16. The gate electrode 16 is used as an extraction electrode for drawing electrons. A spacer 40 is installed between the upper glass substrate 2 and the lower glass substrate 8. The spacer 40 supports the upper glass substrate 2 and the lower glass substrate 8 so as to maintain a high vacuum state between the upper glass substrate 2 and the lower glass substrate 8.

In order to display an image, a negative (-) cathode voltage is applied to the cathode electrode 10 and a positive (+) anode voltage is applied to the anode electrode 4. The gate voltage of positive polarity (+) is applied to the gate electrode 16. Then, the electron beam 30 emitted from the emitter 22 is accelerated toward the anode electrode 4. The electron beam 30 collides with the red, green, and blue phosphors 6 to excite the phosphors 6. At this time, visible light of any one of red, green, and blue colors is generated according to the phosphor 6. The fluorescent substance 6 is arrange | positioned in order of red, green, and blue like FIG. Thus, when the electron beam 30 generated in the subpixel or pixel is accelerated toward the phosphor 6, the phosphor 6 of another color adjacent to the light is emitted by the diffusion of the electron beam 30. In addition, a high voltage of about 10 mA is applied to all the anode electrodes 4 formed on the phosphor 6 to accelerate electrons. Therefore, the electron beam 30 is diffused by the high voltage applied to the anode electrode 4. As a result, not only a lot of power consumption is consumed, but also the color purity of the displayed image is lowered.

Accordingly, it is an object of the present invention to provide a field emission display device and a method of driving the same, which increase color purity and are driven at a low voltage.

1 is a perspective view showing a field emission display device;

FIG. 2 is a cross-sectional view of the field emission display device shown in FIG. 1. FIG.

3 is a plan view illustrating a pixel arrangement of the field emission display device illustrated in FIG. 1.

4 is a cross-sectional view of a field emission display device according to an embodiment of the present invention.

FIG. 5 is a plan view illustrating a pixel arrangement of the field emission display shown in FIG. 4. FIG.

6 is a block diagram illustrating an anode electrode driver according to an exemplary embodiment of the present invention.

7 is an output waveform diagram of an anode electrode driver shown in FIG. 6;

8 is a view showing in detail the driving unit shown in FIG.

<Description of Symbols for Main Parts of Drawings>

2: upper glass substrate 4: anode electrode

6,56: phosphor 8: lower substrate

10 cathode electrode 12 resistive layer

14 gate insulating layer 16 gate electrode

22 emitter 30 electron beam

32: field emission array 40: spacer

60: control unit 62,64,66: drive unit

68: switch 70: transformer

In order to achieve the above object, the field emission display device of the present invention has the same color of adjacent phosphors between pixel cells.

The field emission display device of the present invention includes an anode driver for supplying AC signals having different phases to the anode so that subpixel cells for displaying different colors are driven at different times.

In the field emission display device of the present invention, the adjacent phosphors of the pixel cells have the same color, and the sub-pixel cells for displaying different colors are driven at different times to supply AC signals having different phases to the anodes, respectively. An anode drive unit is provided.

The driving method of the field emission display device of the present invention includes the steps of determining the same color of the adjacent phosphor between the pixel cells, and supplying an AC voltage to the anode electrode.

Other objects and features of the present invention in addition to the above objects will become apparent from the description of the embodiments with reference to the accompanying drawings.

Hereinafter, exemplary embodiments of the present invention will be described with reference to FIGS. 4 to 8.

4 and 5 are views showing the arrangement of the phosphor according to the first embodiment of the present invention.

4 and 5, the FED according to the first embodiment of the present invention has an upper glass substrate 2 having an anode electrode 4 formed thereon and a phosphor 56 having the same subpixel colors of adjacent pixels. ) And a field emission array 32 formed on the lower glass substrate 8. The phosphor 56 emits red (R), green (G), blue (B), blue (B), red (R), green (G), and green (green) colors so that sub-pixels of adjacent pixels can emit light of the same color. G), blue (B), and red (R) in that order. In other words, the pixel colors of adjacent pixels are arranged identically. When the phosphor 56 is disposed in this way, the color to be displayed is displayed even when the electron beam 30 is diffused and collides with the sub-pixels of adjacent pixel cells. In addition, the phosphor 56 of the present invention is red (R), blue (B), green (G), green (G), red (R), blue (B), blue (B), green (G), It may be arranged in the order of red (R).

6 and 7 are diagrams illustrating a driving circuit and a driving waveform according to a second embodiment of the present invention.

6 and 7, the driving circuit according to the second exemplary embodiment of the present invention includes an R driver 62 for supplying an AC voltage to an anode electrode formed on the red phosphor R, and a green phosphor G. G drive unit 64 for supplying an alternating voltage to the anode electrode formed on the ()), B drive unit 66 for supplying an alternating voltage to the anode electrode formed on the blue phosphor (B), R drive unit 62 ), A control unit 60 for controlling the G driving unit 64 and the B driving unit 66. The controller 60 outputs a control signal to drive the drivers 62, 64, 66. The drivers 62, 64, and 66 supply an alternating voltage of about 10 mA to the anode electrode in response to the control signal of the controller 60. In this case, the AC voltages supplied from the driving units 62, 64, and 66 are supplied to the anode electrode formed on the red phosphor R and the anode electrode formed on the blue phosphor B as shown in FIG. 7. After the AC voltage is supplied to the anode electrodes formed on the red and blue phosphors R and B, the AC voltage is supplied to the anode electrodes formed on the red and green phosphors R and G. After the AC voltage is supplied to the anode electrodes formed on the red and green phosphors R and G, the AC voltage is supplied to the anode electrodes formed on the green and blue phosphors G and B. That is, the control unit 60 supplies the AC voltage only to the anode electrodes formed on the two phosphors at the same time. Compared with the conventional method, conventionally, all anode electrodes were supplied with a constant DC voltage of about 10 mA. However, in the present invention, since the AC voltage is supplied only to the anode electrodes formed on the two phosphors at the same time, the electron beam diffusion phenomenon can be minimized. Therefore, the color purity can be improved and the power consumption supplied to the anode can be minimized.

8 is a view illustrating in detail the driving units shown in FIG. 6.

Referring to FIG. 8, the driving units of the present invention are configured with a transformer 70 to prevent the AC voltage of about 10 kV supplied to the anode electrode from being supplied to the controller 60. First, the switch 68 is turned on to supply a control signal supplied from the controller 60 to the transformer 70. The transformer 70 receiving the control signal from the control unit 60 amplifies an AC signal input from a supply unit (not shown) and supplies the amplified AC signal to the anode electrode. At this time, the switch 68 is turned off to prevent the high voltage AC signal from being supplied to the controller 60.

As described above, according to the field emission display device and the driving method thereof according to the present invention, color purity can be improved by arranging the phosphors so that the colors of the sub pixels are the same. In addition, since the AC voltage is applied only to the anode electrodes formed on the two phosphors at the same time, color purity can be improved and power consumption can be minimized.

Those skilled in the art will appreciate that various changes and modifications can be made without departing from the technical spirit of the present invention. Therefore, the technical scope of the present invention should not be limited to the contents described in the detailed description of the specification but should be defined by the claims.

Claims (12)

In a field emission display device in which pixel cells containing red, green, and blue phosphors are arranged in a matrix form, And the color of the adjacent phosphor is the same between the pixel cells. The method of claim 1, And the phosphors are arranged in order of red, green, blue, blue, red, green, green, blue, and red. The method of claim 1, The phosphor is disposed in the order of red, blue, green, green, red, blue, blue, green, red. A subpixel cell in which anodes are formed on red, green, and blue phosphors, respectively; And an anode driver for supplying AC signals having different phases to the anode so that the subpixel cells for displaying different colors are driven at different times. The method of claim 4, wherein And a control unit for supplying a control signal for driving the anode driver. The method of claim 5, The anode drive unit, A red driver for supplying the AC signal to an anode electrode on the red phosphor in response to the control signal; A green driver for supplying the AC signal to an anode electrode on the green phosphor in response to the control signal; And a blue driver for supplying the AC signal to an anode electrode on the blue phosphor in response to the control signal. The method of claim 6, And the control signal is simultaneously supplied to two of the red, green, and blue driving units. The method of claim 6, The red, green and blue drivers, A transformer for amplifying the AC voltage to receive an AC voltage from a power supply and to supply the anode electrode; And a switch for receiving the control signal. The method of claim 8, And the switch is turned on when the control signal is input and is turned off when the amplified AC voltage is supplied to the anode electrode. In the method of driving a field emission display device in which an anode electrode is formed on red, green and blue phosphors, and pixel cells containing the red, green and blue phosphors are arranged in a matrix form. Determining the color of the adjacent phosphor between the pixel cells to be the same; And supplying an alternating current voltage to the anode electrode. The method of claim 10, And the AC voltage is simultaneously supplied to two anode electrodes of the red, green, and blue anode electrodes. In the field emission display device in which an anode electrode is formed on red, green, and blue phosphors, and pixel cells containing the red, green, and blue phosphors are arranged in a matrix form. The colors of the adjacent phosphors between the pixel cells are identically disposed, And an anode driver for supplying AC signals having different phases to the anode so that the subpixel cells for displaying different colors are driven at different times.