KR100293513B1 - Driving method of field emission display device - Google Patents

Abstract

The present invention relates to a method of driving a field emission display device for improving the image quality of the field emission display device.

According to an exemplary embodiment of the present invention, a method of driving a field emission display device includes simultaneously applying a scan pulse to a selected row electrode line and a corresponding anode electrode line, and prevents electrons emitted from the pixel selected by the scan pulse toward an adjacent pixel And applying a voltage not set to the anode electrode lines other than the selected anode electrode line.

According to the present invention, the image quality is improved by preventing crosstalk in the field emission display device.

Description

Driving Method of Field Emission Display

BACKGROUND OF THE INVENTION Field of the Invention The present invention relates to a field emission display device, and more particularly, to a method for classifying a field emission display device for preventing crosstalk of the field emission display device.

In recent years, field emission displays (hereinafter referred to as "FED") are being actively researched for application as next-generation flat panel display devices due to advantages such as excellent display characteristics and manufacturing cost competitiveness. The FED uses a cold cathode that emits electrons by quantum mechanical tunneling by concentrating a high field on a sharp cathode (ie, an emitter tip) like an cathode ray tube using electron beam-excited phosphor emission. At this time, the emitted electrons are accelerated by the voltage between the anode and the cathode to collide with the phosphor film formed on the anode, whereby the phosphor is excited and emitted to display an image.

Referring to FIG. 1, an FED pixel cell according to the related art includes an emitter electrode 2 emitting electrons, a gate electrode 4 extracting electrons from the emitter electrode 2, and the emitted electrons. An anode electrode 6 for inducing and accelerating is provided. The emitter electrode 2 is composed of an emitter conductive layer 2a and an emitter tip 2b, and the emitter driving voltage is applied to the emitter tip 2b in the case of the emitter conductive layer 2a. . In addition, an insulating layer (not shown) is formed between the gate electrode 4 and the emitter conductive layer 2a to electrically isolate the gate electrode 4 and the emitter electrode 2. The anode electrode 6 is formed of a transparent electrode, and a phosphor (not shown) is coated on the lower surface of the anode electrode 6. The scan pulse having a positive voltage level is applied to the gate electrode 4 at the row driver (not shown), and the image data pulse having a negative voltage level at the column driver (not shown) to the emitter electrode 2. When is applied, a voltage above the threshold voltage is supplied between the emitter electrode 2 and the gate electrode 4 to emit electrons from the emitter tip 2b. The emitted electrons are induced by the driving voltage having a constant level applied to the anode electrode 6 and accelerated to collide with the phosphor (not shown) to excite and emit the phosphor. At this time, each pixel (Pixel) of the red (Red (hereinafter referred to as "R"), Green (hereinafter referred to as "G"), Blue (hereinafter referred to as "B") to implement the color It has a sub-pixel. On the other hand, when a fixed voltage having a constant level is applied to the anode electrode 6, since the emitter tip 2b corresponding to each phosphor (not shown) is designated, the former is not required to adjust the anode electrode. Attracted by (6) to cause the phosphor to emit light. However, as the high resolution progresses, the distance per pixel becomes narrower, leading to the problem that electrons are attracted to adjacent pixels, causing crosstalk.

Referring to FIG. 2, a diagram for describing a method of driving a field emission display device is illustrated. As shown in FIG. 2, current is evenly distributed in the emitter conducting layer 2a array by limiting the overcurrent supplied to the emitter tip 2b between the emitter conducting layer 2a and the emitter tip 2b. The resistance layer 16 having a constant resistance value is formed as much as possible. In addition, the anode substrates 6R, 6G, and 6B are formed on the upper substrate so as to correspond to the phosphors 8R, 8G, and 8B of R, G, and B, respectively. The driving voltage is applied to the anode electrodes 6R, 6G, and 6B selected by the switching unit (not shown) according to the image signal to emit the phosphors 8R, 8G, and 8B corresponding to the image signal. In this case, a plurality of emitter tips 2b are formed in one pixel to emit electrons toward the selected phosphors 8R, 8G, and 8B. In this case, R, G, and B must be selected to implement a color, so a high frequency switching circuit is required.

Referring to FIG. 3, a diagram for describing a method of driving a field emission display according to another example is illustrated. As shown in FIG. 3, the emitter array 14 means that the field emission tips (not shown) and the gate electrodes (not shown) are configured in a matrix form. The emitter arrays 14 are configured to match with each phosphor 8. At this time, when voltage is simultaneously supplied to all the anode electrodes 8, crosstalk due to an emission error occurs. For example, the electrons emitted from the emitter array 14a formed at the intersection of the second row line R2 and the third column line C3 are not only the second anode A2 but also the first anode. A problem is induced also in (A1) that causes adjacent phosphors to emit light, thereby causing crosstalk.

Accordingly, an object of the present invention is to provide a method of driving a field emission display device which prevents crosstalk of the field emission display device.

1 is a diagram illustrating a pixel cell structure of a field emission display device according to the related art.

2 is a view for explaining a method of driving a field emission display device according to the prior art.

3 is a view for explaining a method of driving a field emission display device according to another example of the prior art.

4 is a diagram schematically showing a configuration of a field emission display device according to the present invention.

5 is a view for explaining a method of driving a field emission display device according to the present invention.

FIG. 6 is a diagram for explaining another example of the driving waveform of FIG.

* Explanation of symbols for the main parts of the drawings

2,22 emitter electrode 4: gate electrode

6: anode wood electrode 8,26: phosphor

10: upper substrate 12,34: lower substrate

14.24 emitter array 16: resistive layer

28: column driving unit 30: low driving unit

32: anode drive

In order to achieve the above object, the driving method of the field emission display device according to the present invention includes applying a scan pulse to the selected row electrode line and the corresponding anode electrode line at the same time; And applying a voltage set such that electrons are not induced toward adjacent pixels to the anode electrode lines other than the selected anode electrode line.

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

A preferred embodiment of the present invention will be described with reference to FIGS. 4 to 6.

Referring to FIG. 4, a driving device of the field emission display device according to the present invention is connected to m row electrode lines R1 to Rm to sequentially enable the row electrode lines R1 to Rm, respectively. An anode driver 32 connected to the driver 30 and the n anode electrode lines A1 to An to enable the anode electrode lines A1 to An corresponding to the enabled row electrode line. ) And a column driver 28 which is connected to the n column electrode lines C1 to Cn and sequentially supplies the image signal to the column electrode lines C1 to Cn during the period in which the row electrode line is enabled. do. The row driver 30 supplies a scan pulse to sequentially enable the first to m th row electrode lines R1 to Rm. The anode driver 32 enables the anode electrode line corresponding to the enabled row electrode line. Accordingly, since the scan pulse applied to the row electrode line is simultaneously supplied to the anode electrode line corresponding to the row electrode line, the row driving voltage and the anode driving voltage operate in synchronization. In addition, the column driver 28 sequentially supplies the image signal to the first to nth column electrode lines C1 to Cn while the row electrode lines are enabled.

5, the driving method of the field emission display device according to the present invention will be described.

The driving voltage is simultaneously applied to the row electrode line and the corresponding anode electrode line. For example, when a driving voltage (for example, a scan pulse) is applied to the first row electrode line R1, a driving voltage is also applied to the first anode electrode line A1 to correspond to the row electrode line. An anode electrode line is selected at the same time. In fact, the time for displaying the actual image during one frame period is during one horizontal period 1H, so that the driving voltage is supplied only to the corresponding anode line in accordance with the row electrode selection time displayed on the screen. On the other hand, the non-selected anode electrodes A2 to Ak have a voltage (for example, a base voltage or a negative voltage) that does not affect electron emission, that is, a pixel or line adjacent to electrons emitted from the selected pixel or line. The voltage set is not applied to the On the other hand, it will be described in connection with the operation of the row electrode line and column electrode line. When a scan pulse is applied to the first row electrode line R1, the first row electrode line R1 is enabled. While the first row electrode line R1 is enabled, an image signal is sequentially applied to the first to nth column electrode lines C1 to Cn, and in the pixels connected to the first row electrode line C1, The electrons corresponding to the video signal are emitted. Accordingly, a quantity of electrons corresponding to the video signal is emitted from the emitter array 24. At this time, the anode driver 32 applies a driving voltage to the selected anode electrode line to induce electrons emitted from the emitter array 24. On the other hand, the non-selected anode electrode lines A2 to Ak are connected to a ground voltage source or a negative voltage is applied to prevent crosstalk of the emission electrons. By this process, an image corresponding to one line is displayed on the screen. When the process is sequentially performed to the m th row electrode line Rm, an image corresponding to one screen is displayed.

On the other hand, at the intersection of the row electrode lines R1 to Rm and the column electrode lines C1 to Cn, pixels are formed in a matrix form. Since the pixel has a structure in which an emitter electrode (not shown), a gate electrode (not shown), and an anode electrode are disposed up and down at regular intervals, panel capacitance is present. In order to exclude the influence of the capacitance, a scan pulse having a waveform as shown in FIG. 6 which will be described later may be used.

Referring to FIG. 6, a waveform diagram showing a low line driving pulse is illustrated to explain a method of driving a field emission display device according to the present invention. As shown in FIG. 6, the low line driving pulse has a waveform in which a discharge pulse for preventing a discharge delay of the scan pulse is added to a scan pulse for enabling the low line. In this case, the discharge pulse has a phase opposite to that of the scan pulse, thereby rapidly discharging the scan pulse which draws a discharge curve and decreases the voltage level. Accordingly, the scan pulse is quickly returned to the reference level (eg, OV) to prevent the discharge delay of the scan pulse. In addition, the discharge pulse does not affect the scan pulse of the next line. That is, the discharge pulses return to the reference level quickly when the scan pulses enable the corresponding low line, thereby preventing the field emission display from malfunctioning. In addition, the width of the discharge pulse and the magnitude of the voltage level may be set according to the designer's intention to have an optimal waveform corresponding to the panel capacitance of the field emission display device.

As described above, the driving method of the field emission display device according to the present invention has an advantage of improving image quality by preventing crosstalk by simultaneously applying scan pulses to the row electrode line and the corresponding anode electrode line. .

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 (4)

A method of driving a field emission display device that sequentially applies a scan pulse to enable m row electrode lines, Simultaneously applying the scan pulse to the selected row electrode line and the corresponding anode electrode line; And applying a voltage that is set so that electrons emitted from the pixel selected by the scan pulse is not induced toward an adjacent pixel, to an anode electrode line other than the selected anode electrode line. Driving method. The method of claim 1, The scan pulse, And a discharge pulse for accelerating the discharge of the scan pulse is added to the scan pulse. The method of claim 2, And the discharge pulse has a phase opposite to that of the scan pulse. The method of claim 2, And the width and voltage level of the discharge pulse are selected in correspondence with the panel capacitance of the field emission display device.