KR100664028B1 - Field emission display panel and driving method thereof - Google Patents

Abstract

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a field emission display panel capable of improving image quality by reducing electric field distortion caused by charges accumulated in a spacer, and a driving method thereof, wherein a 4N is formed between a spacer supporting an upper substrate and a lower substrate and a spacer. In a method of driving a field emission display panel having a matrix structure in which N is 1 to 5 scan lines, 2N (N is 1 to 5) scan lines adjacent to both sides of the spacer when the first frame is driven. Driving only cells of the system; And driving only the cells that were not driven when the first frame is driven during the next frame driving of the first frame, thereby reducing image distortion of the electron beam around the spacer and improving image quality. By sufficiently securing the discharge time of the accumulated electrons, it is possible to prevent damage to the panel due to abnormal discharge of the accumulated electrons, and to reduce the power consumption due to the reduction of the switching frequency of the driving unit for driving the scan line. .

Description

Field emission display panel and driving method thereof {FIELD EMISSION DISPLAY PANEL AND DRIVING METHOD THEREOF}

1 is a perspective view of a field emission display panel having a general matrix structure.

2 is a diagram illustrating a conventional method for driving a field emission display panel.

3 is a plan view (b) of the shape (a) and the light emission shape of the electron beam according to the conventional driving method of FIG.

4 is an exemplary diagram illustrating a method of driving a field emission display panel for an odd numbered frame according to the present invention.

FIG. 5 is a plan view (b) of the field emission display panel with respect to the shape (a) of the electron beam and the light emission shape according to the driving method of FIG. 4; FIG.

6 is an exemplary diagram illustrating a method of driving a field emission display panel for an even numbered frame according to the present invention.

FIG. 7 is a plan view (b) of the field emission display panel with respect to the shape (a) of the electron beam and the light emission shape according to the driving method of FIG.

** Description of the symbols for the main parts of the drawings **

20: scan line 30: data line

50: spacer 70: phosphor

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a field emission display panel and a driving method thereof, and more particularly, to a field emission display panel and a driving method thereof capable of improving image quality by reducing field distortion caused by charges accumulated in a spacer.

With the rapid development of information and communication technology and the demand for visualization of diversified information, the demand for electronic display devices has increased and the required features have been diversified. For example, in an environment in which mobility is emphasized, such as a portable information device, a display device having a small weight, volume, and power consumption is required, and when used as an information transmission medium for the public, a display device having a wide viewing angle is required.

In addition, a display device for satisfying such a requirement is required to be large, low in price, high performance, high definition, thin, and lightweight, so that a light and thin plate that can replace the existing CRT is required to satisfy such a requirement. The development of display devices is urgently needed.

CRT, which currently occupies most of information display media, has excellent performance, but the larger the screen, the larger the volume and weight, and the higher the voltage and power consumption. Therefore, the rise of flat panel displays is inevitable. Among the flat panel displays currently being developed or produced, liquid crystal display (LCD), plasma display (PDP), and fluorescent display (VFD: Vacuum Fluorescent Display) are commercialized by large manufacturers. The field emission display device (FED), which is expected to be put to practical use in the near future, is drawing attention as a next-generation flat panel display device for overcoming all the disadvantages of these display devices.

Figure 1 shows the FED structure of the matrix structure. As shown, the electrons 80 are formed by the scan electrode 20 and the data electrode 30 formed in a matrix structure on the lower substrate 10, and an electric field applied to the scan electrode 20 and the data electrode 30. And an emitter electrode 40 emitting a light source, a phosphor 70 formed on the upper substrate 60, and a spacer 50 supporting the upper substrate 60 and the lower substrate 10. .

2 illustrates a conventional method of driving a field emission display panel, and it can be seen that data pulses and scan pulses for image data are synchronously applied. That is, when data corresponding to the first scan line SCAN 1 is applied to the data lines D1 to Dm as data pulses of positive voltage, the negative voltage synchronized with the data pulse is applied to the first scan line SCAN 1. A scan pulse is applied to operate a cell corresponding to the first scan line SCAN 1, and this process is sequentially performed for all scan lines SCAN 1 to SCAN n.

3 is a plan view (b) of the shape (a) and the light emission shape of the electron beam according to the conventional driving method of FIG. As shown, a cell is formed where the data lines D1 to Dm and the scan lines SCAN 1 to SCAN n vertically intersect, and all of the formed cells, that is, cells of a scan line adjacent to the spacer 50, and It can be seen that the electron beams are all emitted from the cells of non-adjacent scan lines. Therefore, all the phosphors emit light by the electron beam to display one frame data.

However, before the electrons emitted from the emitter electrode 40 reach the phosphor by the high voltage applied to the upper substrate (anode electrode) 60, the electrons around the spacer 50 accumulate on the surface of the spacer 50. The phenomenon occurs, which causes the electric field distribution near the spacer 50 to be distorted differently from the portion where the spacer 50 does not exist. Therefore, the electric field distribution distortion around the spacer 50 affects the flow of electrons, thereby causing distortion in the acceleration path of electrons due to the high voltage applied to the first anode electrode. That is, when viewed from the front of the panel, the light around the spacer 50 may appear darker or brighter, and the light emitting part may be irregularly distorted. Therefore, where the spacer 50 is present, the shape due to the influence of the spacer 50 appears.

In order to prevent the electric field distortion caused by the electrons accumulated on the surface of the spacer, a method of applying a voltage that neutralizes the electrons accumulated in the spacer and simultaneously neutralizes the electrons accumulated in the current flow through the spacer. Methods have been applied to adjust the resistivity of the spacer so that it can escape.

In addition, the dielectric constant of the spacer may be similar to the vacuum dielectric constant in order to reduce the electric field distortion caused by the structural shape in terms of the breakage or somewhat unevenness of the spacer, or an auxiliary electric field may be installed on the spacer to artificially apply an electric field from the outside. In order to maintain the potential of the spacer evenly, attempts have been made.

However, methods other than the method of adjusting the resistivity of the spacer have a problem in that structural and driving methods are complicated and additional cost is required for panel fabrication.

In addition, the method of adjusting the specific resistance of the spacer is that the electrons accumulated over time after driving the FED do not sufficiently fall out, so that the electric field distortion phenomenon due to the electrons accumulated in the peripheral portion of the spacer gradually occurs, and the visible shape is noticeably distorted. There was this.

Accordingly, the present invention has been made to solve the above-mentioned conventional problems, and only drives scan lines that are not adjacent to the spacer when driving the first frame, and drives only scan lines adjacent to the spacer when driving the next frame of the first frame. It is an object of the present invention to provide a field emission display panel and a driving method thereof capable of improving image quality by reducing a phenomenon in which an electron beam around a spacer is distorted by driving in an interlaced manner.

In addition, the present invention by sufficiently securing the discharge time of the electrons accumulated on the spacer surface, it is possible to prevent damage to the panel due to the abnormal discharge of the accumulated electrons, and to reduce the power consumption by reducing the switching frequency of the drive unit for driving the scan line It is an object of the present invention to provide a field emission display panel and a driving method thereof that can be reduced.

In the field emission display panel of the present invention for achieving the above object, 4N (N is 1 to 5) scan lines are formed between a spacer supporting an upper substrate and a lower substrate and a spacer, and thus, a first frame. In driving, only 2N (N is 1 to 5) scanline cells adjacent to both sides of the spacer are driven, and in the next frame driving of the first frame, only the cells of the scanline that are not driven when the first frame is driven. It is characterized by driving.

The field emission display panel driving method of the present invention for achieving the above object is an electric field of a matrix structure in which 4N (N is 1 to 5) scan lines are formed between the spacer supporting the upper substrate and the lower substrate and the spacer. A method of driving an emission display panel, the method comprising: driving only 2N scan lines adjacent to both sides of the spacer while driving a first frame; And driving only cells that were not driven when the first frame was driven during the next frame driving of the first frame.

A preferred embodiment of the field emission display panel and a driving method thereof according to the present invention having the above characteristics will be described in detail with reference to the accompanying drawings.

Hereinafter, the detailed description of the present invention assumes that four scan lines are formed between the spacers and the first spacer is positioned between the third scan line SCAN 3 and the fourth scan line SCAN 4. .

FIG. 4 shows driving waveforms for odd-numbered frames in the field emission display panel driving method of the present invention. As shown in FIG. 4, scan lines SCAN 1,2,5,6 .. It can be seen that scan pulse is applied only to .n-3, n-2 and scan pulse is not applied to scan lines SCAN 3,4,7,8 ... n-1, n adjacent to the spacer. have.

In addition, it can be seen that a scan pulse is applied to the second scan line SCAN 2 and a scan pulse is directly applied to the fifth scan line SCAN 5. That is, scan pulses are sequentially applied to the scan lines SCAN 1,2,5,6 ... n-3, n-2 that are not adjacent to the spacer, so that only cells of the scan line that are not adjacent to the spacer are driven. Let's do it.

5 is a plan view (b) of the field emission display panel of the present invention with respect to the shape (a) of the electron beam and the light emission shape by the odd-numbered frame driving method according to the present invention. As shown, only the cells of the scan line adjacent to the spacer 50 are free of movement of the electrons 80 (FIG. 5A), and the scan lines SCAN 1,2,5,6 not adjacent to the spacer 50 are shown. Only the cells of ...) are operated so that the phosphor 70 of the corresponding cell emits light by an electron beam to display odd frame data (FIG. 5B).

As the odd-numbered frame is displayed by the driving of the scan line not adjacent to the spacer 50, the even-numbered frame is indicated by the driving of the scan line adjacent to the spacer 50, and a driving method thereof is shown in FIG. It was.

FIG. 6 illustrates driving waveforms for even-numbered frames in the method of driving a field emission display panel according to the present invention. As shown in FIG. 6, scan lines adjacent to the spacer 50 are shown. It can be seen that the scan pulse is applied only to n-1, n, and the scan pulse is not applied to the scan lines SCAN 1,2,5,6 ... that are not adjacent to the spacer 50.

In addition, it can be seen that the scan pulse is applied to the fourth scan line SCAN 4 and the scan pulse is immediately applied to the seventh scan line SCAN 7 as in the odd frame driving method shown in FIG. 4. That is, scan pulses are sequentially applied to the scan lines SCAN 3, 4, 7, 8... Adjacent to the spacer 50 to drive only the cells of the scan line adjacent to the spacer 50.

Fig. 7 shows a plan view (b) of the field emission display panel of the present invention with respect to the shape (a) of the electron beam and the light emission shape by the even-numbered frame driving method according to the present invention. As shown, the path of movement of electrons 80 spans both periphery of spacer 50 (FIG. 7A), and thus scan lines SCAN 3, 4, 7, 8... Adjacent to spacer 50. ) Only the cells corresponding to the < RTI ID = 0.0 >) < / RTI > and the phosphor 70 of the corresponding cell emit light by the electron beam to display even-numbered frame data (FIG. 7B).

As described above, the present invention separates the image data into odd frames and even frames with adjacent frames and adjacent frames, and assembles images similarly to the existing interlacing method to drive two scan lines by skipping them. . By driving in this way, the time is applied to the spacer and the voltage is applied again, and thus, the time allowance is about twice as compared with the conventional driving method, and the time when the charge accumulated in the spacer naturally disappears by the spacer resistance is also about twice as long. It can be secured. Therefore, the electric field distortion around the spacer due to the charge accumulated in the spacer can be reduced, and the image quality can be improved. The structure of the field emission display panel for implementing the present invention can be used only in a structure in which four scan lines are formed between the spacer supporting the upper substrate and the lower substrate and the spacer.

In addition, by including the driving time of the lines that do not drive even when driven in a similar interlace method as the present invention in the driving time of the driving line, the average driving time of the entire cell is kept the same as the existing driving time, so Has little effect. For example, since the number of scan lines driven per frame is reduced by half compared to the number of drive lines shown in FIG. 2, when the present invention is driven with the same data pulse width and scan pulse width as in FIG. It is reduced by half compared to the driving time of FIG. Therefore, in order to make one frame driving time the same as in the present invention, by increasing the data pulse width and the scan pulse width shown in FIGS. 4 and 6 to twice the data pulse width and the scan pulse width shown in FIG. This problem can be solved.

In addition, since the present invention increases the data pulse width and the scan pulse width, the switching frequency of the driver for applying the data pulse and the scan pulse can be reduced, thereby reducing switching power consumption.
In the embodiment of the present invention, it is assumed that four scan lines are formed between the spacer and the spacer, but the present invention is not limited thereto, and four scan lines, eight scan lines, and 12 scans are formed between the spacers and the spacers. Lines, ... 20 scan lines may exist. As such, the reason for limiting the number of scan lines to a multiple of 4 is that when the scan lines are driven alternately every frame, the quantitative ratio of the driven scan lines must be equal.
That is, during driving of the first frame, only half (2N) of the scan lines (4N) between the spacers and the spacers are driven, and each quarter (i.e. N) is on both sides (adjacent to the spacer). It is driven separately (ie 2N in the center is not driven, only N in each side).
Subsequently, when driving the second frame (next frame of the first frame), only 2N scan lines positioned in the center of the scan lines between the spacers are driven.
That is, although an embodiment of the present invention refers to the case where four scan lines are formed, the present invention is applied even when eight scan lines are formed, and the same applies to the case where there are 12, 16, and 20 scan lines. to be.
However, the limit of the number of scan lines existing between the spacers and the spacers is limited to 20 because, in case of more than 20 scan lines exist between the spacers and the spacers, the structural features of the spacers that must withstand a considerable pressure, the device characteristics Because it may lead to degradation.

As described in detail above, the present invention drives the scan line that is not adjacent to the spacer when driving the odd frame, and drives the electron beam around the spacer by driving the interlace method that drives only the scan line adjacent to the spacer when driving the even frame. By reducing the phenomena, the image quality can be improved.

In addition, the present invention by sufficiently securing the discharge time of the electrons accumulated on the spacer surface, it is possible to prevent damage to the panel due to the abnormal discharge of the accumulated electrons, and to reduce the power consumption by reducing the switching frequency of the drive unit for driving the scan line There is an effect that can be reduced.

Claims (4)

4N (N is 1 to 5) scan lines are formed between the spacer supporting the upper substrate and the lower substrate and the spacer, and 2N (N is 1 to 5) adjacent to both sides of the spacer when the first frame is driven. And driving only the cells of the scan lines, and driving only the cells of the scan lines which were not driven when the first frame was driven when the next frame of the first frame is driven. delete In a driving method of a field emission display panel having a matrix structure in which 4N (N is 1 to 5) scan lines are formed between a spacer supporting an upper substrate and a lower substrate and between the spacers. Driving only 2N (N is 1 to 5) cells of the scanline adjacent to both sides of the spacer when the first frame is driven; And Driving only cells that were not driven when driving the first frame when driving the next frame of the first frame; The driving method of the field emission display panel, characterized in that made. The scan pulse width of claim 3, wherein the scan pulse width is applied to the scan line. A method of driving a field emission display panel, wherein the scan pulse width is twice the width of a scan pulse applied when all the scan lines are driven to display one frame data.

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