JP2008111892A - Video display apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a technique for displaying a high quality video by favorably suppressing an afterimage phenomenon and a degradation in luminance. <P>SOLUTION: This video display apparatus includes a plurality of display elements (60) corresponding to each pixel of a display picture, a driving voltage supply part (4) for applying a driving voltage corresponding to a video signal to the display elements, and an afterimage correcting circuit (9) for correcting the driving voltage. The afterimage correcting circuit corrects the driving voltage using a first correction signal which is produced in response to a change in the driving voltage and varies with time, and a second correction voltage for applying an offset to the driving signal. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an image quality correction technique in an image display apparatus using an electron emission element such as a thin film electron source or an organic EL (electroluminescence) element.

  In a video display device using an electric field such as a thin-film electron source or an electron-emitting device, or an organic EL device, a phenomenon called “afterimage” occurs due to a sudden change in luminance of a display video. For example, when a white bright image is displayed on a part of a dark image and a gray image is displayed on the entire surface immediately thereafter, the white image portion is temporarily displayed at a lower brightness than that of the gray image. Is done. The luminance of this video portion becomes equal to the luminance of the gray video as time elapses, but it may take several seconds until both luminances become equal.

  Such a phenomenon of partial reduction in luminance that temporarily occurs with a change in luminance is called an “afterimage phenomenon”, and is known, for example, in Patent Document 1 below. And in patent document 1, in order to reduce this afterimage phenomenon, the signal for driving display elements, such as an organic EL element, is correct | amended according to the correction coefficient according to the difference of the luminance signal between fields.

JP 2003-288052 A

  However, in the above-mentioned Patent Document 1, only a so-called afterimage phenomenon is considered, and the overall luminance reduction is not considered. For example, in a field emission device (FED) using an electron emission element such as a thin film electron source, an image having a luminance corresponding to the drive voltage can be displayed at the moment when the drive voltage is applied to the electron emission element. The luminance decreases with the passage of time, and an image can be displayed only at a luminance lower than the luminance that can be displayed with this driving voltage. That is, since the thin-film electron source is a capacitive electron-emitting device, electric charges are accumulated with the lapse of time for applying a driving voltage to the electron-emitting devices, and this electric charge prevents or reduces the emission of electrons. This is probably because of this. It is considered that the amount of charge accumulated in the electron-emitting device substantially follows the level of the driving voltage.

  Therefore, in a display element in which a desired luminance corresponding to the driving voltage cannot be obtained by such charge accumulation, it is necessary to consider a reduction in luminance due to charge accumulation as well as a reduction in afterimage phenomenon.

  The present invention has been made in view of such problems, and an object of the present invention is to provide a technique capable of displaying a high-quality image while satisfactorily suppressing an afterimage phenomenon and a decrease in luminance. It is in.

  In order to achieve the above object, an image display apparatus according to the present invention includes an improved correction circuit. The correction circuit according to the present invention includes a first correction signal that is generated in response to a change in driving voltage for driving the display element and that changes with time, and a first correction signal that gives an offset to the driving signal. The driving voltage is corrected using the correction signal 2.

  The level of the first correction signal may converge to the offset level over time, and the offset level may increase as the drive voltage level increases. Further, these correction signals may be generated according to the driving history of the electron source.

  According to the present invention, good image quality correction can be performed, and high-quality video can be displayed.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the following embodiments, a passive matrix drive type electron emission element type image display apparatus having an MIM (Metal-Insulator-Metal) type electron source as an electron source will be described as an example. However, this embodiment can be similarly applied to electron sources other than MIM, for example, an SCE (Surface Conduction Electron Emitter) type, a carbon nanotube type, a BSD (Ballistic electron Surface-emitting Device) type, and a Spindt type. Furthermore, the present invention can be similarly applied to a display device using an organic EL element.

  Before describing the embodiment of the present invention, the above-mentioned afterimage phenomenon will be described with reference to FIGS. The upper part of FIG. 1 shows the input signal amplitude, and the lower part shows a display video (video visually recognized by the user) corresponding to the upper input signal. Hereinafter, a display image when the signals shown in FIGS. 1A to 1D are sequentially input will be described.

  FIG. 1A shows an example of a display video signal. The display area 1 has a signal amplitude of 100% (255 gradations in 8-bit digital notation. Hereinafter, the signal amplitude will be described in 8-bit digital notation). Is a signal of 0 gradation. A display image corresponding to the input signal (a) is as shown in (a ′). After inputting the signal of FIG. 1 (a) for a certain time, the video signal shown in FIG. 1 (b) is input. Here, since FIG. 1B is a signal for displaying 128 gradations on the entire screen, both the display areas 1 and 2 in FIG. 1B have 128 gradations. The display image at this time is as shown in FIG. 1 (b ′), and the display area 1 in FIG. 1 (b ′) is the display area 2 in spite of trying to display signals of the same gradation over the entire screen. The brightness is lower than that. If the video signals shown in FIGS. 1 (c) and 1 (d), which are the same signals as in FIG. 1 (b), are input as they are, the displayed video will gradually be displayed as shown in FIG. 1 (c ′). The luminance difference between the display area 1 and the display area 2 becomes small, and after a certain period of time, the luminance difference disappears as shown in FIG.

  FIG. 2 shows the temporal change in luminance in the display areas 1 and 2 of FIG. 1 described above. In FIG. 2, the horizontal axis indicates time, and the vertical axis indicates luminance. In FIG. 1, the solid line indicates the luminance of the display area 1 in FIG. 1, and the dotted line indicates the luminance of the display area 2 in FIG. The time (a) region corresponds to the time during which the video signal in FIG. 1 (a) is input. As is clear from FIG. 2, the luminance of the display area 1 is highest at the moment when the input signal (a) is input, and is displayed at a desired gradation (ie, 255 gradations) corresponding to the input signal (a). . And, it becomes almost constant at the time that has decreased with the passage of time. That is, as time elapses, the gradation obtained with a certain level of input signal becomes lower than the desired gradation. The region of time (b) corresponds to the time during which the video signal in FIG. 1B (same as FIGS. 1C and 1D) is input. At the moment when the input signal is switched from (a) to (b), the luminance of the display area 1 becomes lower than the desired gradation (127 gradations) obtained from the input signal (b). It gradually increases over time (c) and (d), and becomes substantially constant at a certain time.

  On the other hand, the luminance of the display area 2 is equal to a desired gradation (127 gradations) obtained from the input signal (b) at the moment when the input signal is switched from (a) to (b). Then, it gradually decreases over time (c) and (d), becomes substantially constant at a certain time, and becomes equal to the luminance of the display area 1. Further, although not explicitly shown in FIG. 1, when a signal having a signal amplitude of 0% is input to the display area 1 at time (c) and a signal amplitude of 100% is input again at time (d), time (a) ) And time (b), the decrease in luminance is recovered, and the same luminance display as in time (a) is obtained.

  As a result of the study of the afterimage phenomenon represented by FIGS. 1 and 2, the inventors have confirmed the following events (i) to (iv).

    (i) When video is displayed, the luminance decreases according to the input signal and the display time.

    (ii) The luminance decreases greatly as the gray level increases and the time increases.

    (iii) The luminance drop is saturated after a certain time, and the saturation value varies depending on the gradation.

    (iv) The decrease in luminance is recovered by performing low gradation display.

  These events are considered to be caused by the capacitive nature of the MIM type electron source which is a thin film type electron source. That is, it is considered that charges are accumulated in the MIM type electron source depending on the application time of the drive signal corresponding to the input video signal applied to the electron source, and the electron emission is hindered or reduced by the charge. Further, it is considered that the amount of charge accumulated in the electron source substantially follows the drive voltage level. That is, the higher the drive voltage level (the higher the video signal level), the greater the reduction in luminance.

  The present invention is configured in view of the phenomenon related to the afterimage phenomenon, and an example thereof will be described below.

  FIG. 3 shows a first embodiment of a video display apparatus according to the present invention. The video signal is input to the video signal input terminal 3 and supplied to the signal processing circuit 7. In the signal processing circuit 7, for example, resolution conversion that matches the definition of the video signal with the resolution of the display panel 20 is performed. Here, the display panel 20 includes the back substrate 6 and the front substrate 30, and details thereof will be described later.

  In addition to the resolution conversion process, the signal processing circuit 7 performs image quality adjustment such as contrast, brightness, and gamma correction. This image quality adjustment may be made to respond to a manual operation by the user. The signal processed by the signal processing circuit 7 is supplied to the scanning line correction circuit 8. The scanning line correction circuit 8 corrects the signal from the signal processing circuit 7 so as to compensate for a voltage drop due to the wiring resistance of the scanning line 51 provided on the back substrate 6. The signal processed by the scanning line correction circuit 8 is input to the afterimage correction circuit 9. The afterimage correction circuit 9 is connected to an external volatile memory 11, and the volatile memory 11 stores correction parameters for afterimage correction corresponding to each of a plurality of electron-emitting devices or pixels. The afterimage correction circuit 9 corrects the output signal from the scanning line correction circuit 8 using the parameters stored in the volatile memory 11 so as to reduce the above-described afterimage. Details of the afterimage correction circuit 9 will be described later.

  A synchronization signal corresponding to the video signal is input to the synchronization signal input terminal 1 and supplied to the timing controller 2. In the timing controller 2, a timing pulse synchronized with the synchronization signal is generated and supplied to the scanning line control circuit 5, the signal line control circuit 4, and the correction circuit 8.

  On the other hand, the display panel 20 has a back substrate 6 made of a glass substrate and a front substrate 8 also made of a glass substrate. On the rear substrate 6, a plurality of scanning lines 51 extending in the horizontal direction of the screen are arranged side by side in the vertical direction of the screen, and a plurality of signal lines 41 extending in the vertical direction of the screen are arranged in the horizontal direction of the screen. The scanning lines 51 and the signal lines 41 are orthogonal to each other, and an electron source (electron-emitting device) 60 connected to the scanning lines and the signal lines is disposed at each intersection.

  A signal line control circuit 4 that is a drive voltage supply unit is connected to the upper end of the signal line 41. The signal line control circuit 4 generates a drive voltage based on the video signal corrected by the afterimage correction circuit 10 and supplies it to each signal line 41.

  On the other hand, the scanning line control circuit 5 is connected to the left end of the scanning line 51. The scanning line control circuit 5 supplies the scanning line 51 with a scanning voltage for selecting one or two scanning lines 51 in synchronization with the horizontal cycle signal from the timing controller 2. That is, the scanning line control circuit 5 performs vertical scanning by selecting one or two rows of electron sources in order from the top in the horizontal period. In this embodiment, the scanning voltage has the same polarity as the driving voltage. That is, both the driving voltage and the scanning voltage are negative or positive. However, the scanning voltage and the signal voltage may have opposite polarities, for example, the driving voltage may be positive and the scanning voltage may be negative.

  When a signal voltage from the signal line control circuit 4 is supplied to each electron source 60 connected to the scanning line selected by the scanning voltage, a potential difference between the scanning voltage and the signal voltage is generated in each electron source 60. . When this potential difference exceeds a predetermined threshold value, a current flows from the scanning line to the signal line via the electron source. Hereinafter, the current flowing through the electron source is referred to as a drive current. When a drive current flows through the electron source, the electron source generates or emits electrons. When the potential difference is equal to or greater than the threshold value, the drive current and the amount of emitted electrons increase nonlinearly with respect to the potential difference. Such a relationship between the potential difference and the drive current is referred to herein as a drive current characteristic. This drive current characteristic indicates the operation characteristic of the electron source, and typically has a characteristic as shown by a solid line in FIG.

  In addition, a front substrate 30 is disposed facing the back substrate 6, and phosphors 31 are disposed at positions facing the respective electron sources 60 on the surface of the front substrate 30 facing the back substrate 6. Yes. Further, the front substrate 30 is provided with an acceleration electrode (not shown), and the acceleration electrode is connected to the high voltage control circuit 10 so that a high voltage from the high voltage control circuit 10 is supplied. The space between the back substrate 6 and the front substrate 30 is a vacuum atmosphere. The electrons emitted from the electron source 60 are accelerated by the high voltage supplied from the high voltage control circuit 10 to the accelerating electrode, travel in the vacuum, and collide with the phosphor. As a result, the phosphor is excited and emits light. The light is emitted to the outside through a transparent glass substrate constituting the front substrate 30, and an image is formed on the display panel 20.

  Next, details of the afterimage correction circuit 9, which is a characteristic part of the present embodiment, will be described. FIG. 8 shows an example of the drive voltage before correction and the drive voltage waveform corrected by the afterimage correction circuit 9, and shows the drive voltage waveform when the same video signal as shown in FIG. 1 is input. . However, only the drive voltage corresponding to the display area 1 is shown here for ease of explanation. In FIG. 8, the regions (a) to (d) in the time on the horizontal axis correspond to the regions (a) to (d) in FIG. The vertical axis represents voltage value or luminance.

  The solid line indicates the drive voltage waveform before correction. In consideration of the addition of the correction signal, the gradation is compressed in advance by the signal processing circuit 7, the scanning line correction circuit 8, or the afterimage correction circuit 9, for example. . For example, when the gradation of the input video signal is 255, it is compressed to 220, for example, as shown in FIG. The dotted line indicates the luminance of the virtual display image when the drive voltage before correction is applied to the electron source 60. A chain line indicates a corrected drive voltage waveform, and includes a first correction signal including a time change surrounded by a circle and a second correction signal including an offset. The first correction signal is generated in the afterimage correction circuit 9 in response to a change (when switching) of the video signal, and has a characteristic that changes with the passage of time from the change. The characteristic of this change is formed so as to be symmetric with respect to the change in luminance of the display image indicated by the dotted line with reference to the gradation of the drive voltage.

  When a driving voltage of 110 gradations is continuously applied to the electron source 60, the first correction signal converges to a certain value after a predetermined time has elapsed. This value is the offset shown in FIG. 8, and a second correction signal including the offset is generated by the afterimage correction circuit 9 together with the first correction signal. As described above, the amount of charge accumulated in the electron source tends to increase as the drive voltage level increases (in proportion to the drive voltage level). Therefore, the drive voltage gradation increases as the drive voltage gradation increases. And the gradation of the actually displayed image becomes large. Therefore, the afterimage correction circuit 9 changes the offset value according to the gradation of the drive voltage (input video signal). For example, when the driving voltage is 110 gradations and the display brightness can be obtained only for 100 gradations due to the accumulation of charges in the electron source, an offset for 10 gradations is generated, the driving voltage is 220 gradations, When the display luminance can be obtained only for 190 gradations due to the charge accumulation in the electron source, an offset for 30 gradations is generated. That is, the afterimage correction circuit 9 generates an offset having a larger value as the gradation of the drive voltage (input video signal) is higher.

  Such a relationship between the gradation of the drive voltage and the offset is set, for example, by acquiring the drive history of the electron source. For example, a current detection circuit is provided in the scanning line 51, the drive current for each gradation of the drive voltage is detected by this detection circuit, and each gradation of the drive voltage and the display brightness (the display brightness and the drive current are in a proportional relationship). Are stored in the volatile memory 11, the driving history can be acquired. The characteristic of the time change due to the first correction signal can also be set by acquiring the drive history in the same manner.

  In this way, the afterimage correction circuit 9 generates first and second correction signals, and corrects the drive signal for each electron source using the first and second correction signals. As described above, according to the configuration of the afterimage correction circuit 9 according to the present embodiment, the first and second correction signals are used so as to cancel the luminance change and the luminance decrease of the display image indicated by the dotted line in FIG. Since the drive voltage is corrected, the above-mentioned afterimage phenomenon can be reduced, and a decrease in luminance associated with charge accumulation in the electron source can be suppressed.

Next, a specific example of the afterimage correction circuit 9 according to the present embodiment will be described with reference to FIG. The afterimage correction circuit 9 according to the present embodiment has a corrected drive voltage as V _OUT , a drive voltage corresponding to the input video signal as V _in , and a correction parameter at the nth frame as a correction signal as ΔV _n . The drive voltage of each electron source (pixel) is corrected by, for example, the following equation 1 to compensate for the afterimage.

但し、α、βはそれぞれ０≦α≦１、０≦β≦１を満たす定数であり、ΔＶ_n-1は、ｎ−１フレーム目における補正パラメータを示す。

However, α and β are constants that satisfy 0 ≦ α ≦ 1 and 0 ≦ β ≦ 1, respectively, and ΔV _n−1 indicates a correction parameter in the (n−1) th frame.

The afterimage is generated because the drive current characteristic in FIG. 4 changes from the solid line to the dotted line. Equation 1 is an equation for calculating the change amount ΔV _n and the drive voltage V _OUT corresponding to the drive current to be originally flowed in the changed drive current characteristic. Note that Vo in FIG. 4 corresponds to the above-described offset, and a correction signal for the drive voltage in which both the time change and the offset are taken into account is generated by calculating the correction signal according to the characteristics of FIG. Obtainable. The characteristics shown in FIG. 4 can be obtained by monitoring the drive history as described above.

FIG. 5 is a block diagram showing a specific example of the burn-in correction circuit 9. Video signal input to the residual image correction circuit 9 is converted into the drive voltage V _in corresponding to a video signal at gradation voltage conversion block 901. The register 902 stores a value corresponding to α in Equation 1, and a multiplier 903 multiplies V _in by α. On the other hand, the volatile memory 11 holds ΔV _n−1 corresponding to each of all the pixels, and reads ΔV _n−1 corresponding to the pixel to be corrected from the memory IF 904 by the synchronization signal. The read ΔV _n−1 is multiplied by a multiplier 906 by a value corresponding to β in the number 1 stored in the register 905. The multiplication value of V _in and α and the multiplication value of ΔV _n−1 and β are added by an adder 907, held as ΔV _n in the volatile memory 11, and used for correction of the next frame. ΔV _n and V _in are added by the adder 908 and input to the voltage gradation conversion block 909 as V _OUT .

Then, V _OUT is converted into a video signal corresponding to the drive voltage by the voltage gradation conversion block 909 and input to the signal line control circuit 4. With the above configuration, the luminance of the display areas 1 and 2 described in FIG. 3 is as shown in FIG. At time (a) in FIG. 7, the brightness of the display area 1 is constant without decreasing, and at time (b), the brightness of the display area 1 and the display area 2 is the same. Further, at time (d), the luminance of the display area 1 is constant as in time (a).

  As described above, according to the present embodiment, the afterimage phenomenon can be reduced and the decrease in luminance can be suppressed. Therefore, the video display apparatus according to the present embodiment can display a higher quality video.

In the first embodiment, in the short-term burn-in correction circuit 9, the gradation of the video signal is converted into the drive voltage. However, the correction may be performed without conversion into the drive voltage. The present embodiment is an example in which correction is performed without performing conversion to a drive voltage, and details thereof will be described with reference to FIG. The difference from the first embodiment is the formula used for correction and the configuration of the afterimage correction circuit 9. The afterimage correction circuit 9 according to this embodiment has a corrected drive voltage as D _OUT , a drive voltage corresponding to the input video signal as D _in , and a correction parameter as a correction signal at the nth frame as ΔD _n . The drive voltage of each electron source (pixel) is corrected by, for example, the following formula 2 to compensate for the afterimage. This number 2 is an expression for calculating the effective drop of the video signal due to the afterimage.

但し、α、βはそれぞれ０≦α≦１、０≦β≦１を満たす定数であり、ΔＤ_n-1は、ｎ−１フレーム目における補正パラメータを示す。

However, α and β are constants that satisfy 0 ≦ α ≦ 1 and 0 ≦ β ≦ 1, respectively, and ΔD _n−1 indicates a correction parameter in the (n−1) th frame.

FIG. 6 is a block diagram showing a specific example of the afterimage correction circuit 9 in the second embodiment. Short burn-correction circuit 9 video signal D _in input to, is multiplied by the value a multiplier 903 which corresponds to the number 2 alpha stored in the register 902. On the other hand, the volatile memory 11 holds ΔD _n−1 corresponding to each of all the pixels, and reads ΔD _{n−1 of the} pixel to be corrected from the memory IF 904 by the synchronization signal. The read ΔD _n−1 is multiplied by a multiplier 906 by a value corresponding to β in Equation 2 stored in the register 905. The product of D _in and α. And the multiplication value of ΔD _n−1 and β is added by an adder 907, held as ΔD _n in a volatile memory, and used for correction of the next frame. ΔD _n and D _in are added by an adder 908 and input to the signal line control circuit 4 as D _OUT .

  With the above configuration, it is possible to correct the afterimage without using the gradation voltage conversion block and the voltage gradation conversion block. Even in the correction according to this embodiment, the afterimage phenomenon and the luminance decrease can be corrected as shown in FIG.

The figure for demonstrating an afterimage phenomenon and a brightness fall. The figure for demonstrating an afterimage phenomenon and a brightness fall. The figure which shows the 1st Example which concerns on this invention. The figure which shows an example of the relationship between a drive voltage and a drive current. FIG. 3 is a block diagram showing a specific example of a position of an afterimage correction circuit 9 in the first embodiment. The block diagram which shows the specific example of the position of the afterimage correction circuit 9 in 2nd Example. The figure which shows the effect of this invention. The figure which shows the waveform of the drive voltage correct | amended by this embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Synchronization signal input terminal, 2 ... Timing controller, 3 ... Video signal input terminal, 4 ... Signal line control circuit, 5 ... Scanning line control circuit, 6 ... Display panel, 7 ... Signal processing circuit, 8 ... Scanning line voltage correction Circuit 9 Short-term burn-in correction circuit 10 High-voltage control circuit 11 Volatile memory 41-43 Signal line 51-53 Scan line 901 Gradation voltage conversion block 902 Register 903 Multiplication 904 ... memory IF, 905 ... register, 906 ... multiplier, 907 ... adder, 908 ... adder, 909 ... voltage gradation conversion block

Claims (16)

In the video display device,
A plurality of display elements corresponding to each pixel of the display screen;
A driving voltage supply unit that applies a driving voltage corresponding to a video signal to the display element;
A correction circuit for correcting the drive voltage from the drive voltage supply unit,
The correction circuit uses the first correction signal that is generated in response to the change in the drive voltage and changes with time, and the second correction signal for giving an offset to the drive signal. An image display device that corrects a voltage.   The video display device according to claim 1, wherein the level of the first correction signal is converged to the level of the offset as time elapses.   2. The video display device according to claim 1, wherein the level of the offset changes according to the level of the drive voltage.   4. The video display device according to claim 3, wherein the level of the offset increases as the level of the drive voltage increases.   2. The video display device according to claim 1, wherein the display element is composed of organic EL (electroluminescence).   The video display device according to claim 1, wherein the display element includes an electric field or an electron-emitting device. In the video display device,
A plurality of scan lines;
A scanning line control circuit connected to at least one of the left and right ends of the plurality of scanning lines and sequentially applying a scanning voltage to the plurality of scanning lines;
Multiple signal lines,
A signal line control circuit that is connected to the plurality of signal lines and applies a driving voltage corresponding to the input video signal to the plurality of signal lines;
An electron source connected to intersections of the plurality of scanning lines and the plurality of signal lines, respectively, and emitting electrons in accordance with a potential difference between the scanning voltage and the driving voltage;
A phosphor that emits light when excited by electrons emitted from the electron source;
A correction circuit for correcting each drive voltage applied to the electron source,
The correction circuit uses the first correction signal that is generated in response to the change in the drive voltage and changes with time, and the second correction signal for giving an offset to the drive signal. An image display device that corrects a voltage.   8. The video display device according to claim 7, wherein the electron source is configured by sandwiching an insulator between two metal layers.   8. The video display device according to claim 7, wherein the level of the first correction signal is converged to the offset level over time, and the level of the offset increases as the level of the drive voltage increases. A characteristic video display device. In the video display device,
A plurality of scan lines;
A scanning line control circuit connected to at least one of the left and right ends of the plurality of scanning lines and sequentially applying a scanning voltage to the plurality of scanning lines;
Multiple signal lines,
A signal line control circuit that is connected to the plurality of signal lines and applies a driving voltage corresponding to the input video signal to the plurality of signal lines;
An electron source connected to intersections of the plurality of scanning lines and the plurality of signal lines, respectively, and emitting electrons in accordance with a potential difference between the scanning voltage and the driving voltage;
A phosphor that emits light when excited by electrons emitted from the electron source;
A correction circuit for correcting each drive voltage applied to the electron source,
The video display device, wherein the correction circuit corrects the driving voltage using a correction signal corresponding to a driving history of the electron source.   The video display device according to claim 10, wherein a correction signal added to each drive voltage is changed by the input video signal.   The video display device according to claim 10, further comprising a memory unit connected to the correction circuit and configured to hold a value calculated from a driving history of the electron source.   13. The video display device according to claim 12, wherein the memory unit holds correction signal data corresponding to each electron source.   13. The video display device according to claim 12, wherein data stored in the memory unit is changed by the input video signal. 11. The video display device according to claim 10, wherein the correction circuit corrects the drive voltage by adding the correction signal to the drive voltage, and the drive signal corrected by the correction signal is expressed as V. _OUT , when the drive voltage corresponding to the input video signal is V _in and the correction signal is expressed as ΔV _n as a correction parameter in the nth frame, the drive signal is corrected based on the following formula 1. A video display device characterized by the above.

However, 0 ≦ α ≦ 1 and 0 ≦ β ≦ 1, and ΔV _n−1 represents a correction parameter in the (n−1) th frame. The video display device according to claim 10, wherein the correction circuit corrects the drive voltage by adding the correction signal to the input video signal, and the corrected video signal is represented by D _OUT , an input video signal D _in, further said correction signal, when expressed in [Delta] D _n as a correction parameter based on the pixel driving history in the n th frame, and characterized in that to correct the drive signal based on the following Expression 2 Video display device.

However, 0 ≦ α ≦ 1 and 0 ≦ β ≦ 1, and ΔD _n−1 represents a correction parameter in the (n−1) th frame.

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