JP2008139561A - Image display device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent a luminance change by providing the element current meeting image data even if an electron emission element changes with lapse of time, and also to prevent a smear from changing with lapse of time by keeping constant the voltage drop generated by the current flow in a scanning line. <P>SOLUTION: A scanning line current is detected by a detection resistor 1 and current detection data 8 are obtained by an adder/subtractor 5 and an A/Z converter 2. The current detection data 8 are input to a voltage correction circuit 6, which operates the correction amount of the scanning selection voltage and the data voltage and outputs a correction signal 10. A scanning voltage correction circuit 16 performs correction of the scanning selection voltage by using the correction signal 10. Also, the voltage correction circuit 6 generates data electrode driving data 11 from the current detection data 8 and the image data 207 and inputs the data to a data electrode driving circuit 7. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an image display device in which electron-emitting devices are arranged in a matrix.

  In recent years, electron emission elements are provided at the intersections of wirings orthogonal to each other, and the amount of electrons emitted from the electron emission elements is controlled by modulating the voltage or time applied to each electron emission element. Self-luminous matrix-type displays that accelerate and irradiate phosphors are attracting attention. Electron emitting devices used in this type of display include metal / insulating film / metal type, field emission type, and surface conduction type.

  A display panel using electron-emitting devices includes a back plate provided with a plurality of electron-emitting devices arranged in a matrix, wiring for driving these electron-emitting devices, and a front plate coated with a phosphor. It consists of and.

  FIG. 8 is a schematic view of a back plate in the display panel. In FIG. 8, reference numeral 201 denotes an electron-emitting device constituting each pixel. The electron-emitting device 201 is disposed at the intersection of the vertical data line 202 and the horizontal scanning line 203 and is connected to each wiring. D1 to Dm are data electrodes for applying a data signal to each data line 201, and S1 to Sn are scan electrodes for applying a scanning selection voltage and a scanning non-selection voltage to each scanning line 203.

  FIG. 9 is a Log (I) -V characteristic diagram of the voltage V applied to the electron-emitting device 201 and the device current I (logarithmic axis) flowing through the electron-emitting device. In FIG. 9, the device current I flowing with respect to the applied voltage V increases exponentially. The characteristics of the device current I flowing in the electron-emitting device with respect to the applied voltage V to the electron-emitting device are as follows. The threshold voltage Vth when the device current I is a predetermined threshold current Ith and the slope α of the device current I with respect to the applied voltage V And can be expressed approximately.

  FIG. 10 shows a drive circuit for driving a display panel using electron-emitting devices. Note that a case where a current flows through the electron-emitting device when the scanning line voltage is higher than the data line voltage will be described.

  In FIG. 10, the timing controller 205 receives the image signal 210 and the synchronization signal 204, generates and outputs the control signal 208 and the image data 207 to the data electrode drive circuit 7, and controls the scan electrode selection circuit 30 to A signal 214 is generated and output.

  The data electrode drive circuit 7 outputs a data voltage to the data electrodes D1 to Dm on the back plate constituting the display panel 215. The scan electrode selection circuit 30 outputs a scan selection voltage to one of the scan electrodes S <b> 1 to Sm on the back plate constituting the display panel 215.

  In the scan electrode selection circuit 30, one of the scan selection switches SH1 to SHn is selected and turned on based on the control signal 214, and one of the scan electrodes S1 to Sn of the selected scan line is set to the first. A scan selection voltage from the reference voltage source 211 is applied. Further, the plurality of non-select switches SL1 to SLn corresponding to the scan lines in the non-selected state are turned on to supply the scan non-select voltage from the second reference voltage source 212 to the scan electrodes. FIG. 10 shows a case where the scan selection switch SH2 is selected. The high voltage circuit 220 supplies a high voltage to the front plate of the display panel 215.

  FIG. 11 is an operation waveform diagram when line-sequential operation is performed in the drive circuit shown in FIG. In FIG. 11, for example, a signal VSH1 is a control signal for the scan selection switch SH1, and the scan selection switch SH1 is turned on when it is at a high level.

  The vertical scanning starts from the selection operation from the scanning line connected to the scanning electrode S1. When the signal VSH1 becomes high level during the period T1, the scan selection switch SH1 is turned on, and the scan selection voltage is applied to the first scan electrode S1. At this time, the data electrode drive circuit 7 supplies data voltages Vd11 to Vd1m corresponding to the image data 207 to the data electrodes D1 to Dm.

  Next, when the signal VSH2 becomes high level during the period T2, the scan selection switch SH2 is turned on, and the scan selection voltage is supplied to the second scan electrode S2. Data voltages Vd21 to Vd2m at this time are supplied to the data electrodes D1 to Dm. These operations are sequentially performed, and image data for one field is displayed on the display panel.

  As described above, the image display device in which the electron-emitting devices are arranged in a matrix has a problem that the luminance changes due to a change with time of the element current flowing from the front plate to the back plate. In order to solve this problem, Japanese Patent Application Laid-Open Publication No. 2004-228561 detects the emission current by a detection resistor connected to the negative electrode side of the high voltage circuit, performs A / D conversion on the detected current value, and sets the current data in advance. It is described that the voltage applied to the electron-emitting device is controlled so as to match the reference value.

  Also, most of the device current is not emitted as electrons to the front plate, but flows to the scanning line, a voltage drop occurs due to the scanning line resistance and the ON resistance of the selection switch of the scanning electrode selection circuit, and the image quality is improved by a luminance step called smear. to degrade. In order to solve this problem, Japanese Patent Application Laid-Open No. 2005-228561 describes that the data voltage is corrected so as to compensate for the voltage drop of each part of the scanning line determined according to the image signal.

Further, in Patent Document 3 below, even if a voltage drop occurs due to the on-resistance of the selection switch of the scanning electrode selection circuit and the current flowing according to the image signal, the scanning selection voltage output to the scanning electrode has a predetermined reference value. It is described that it drives so that it may become.
Japanese Patent Laid-Open No. 2001-202059 Japanese Patent No. 3311201 JP 2004-86130 A

  The emission current that flows from the front plate to the back plate that determines the luminance of the display panel is (1) the device current I that flows through the electron-emitting device when an applied voltage V is applied to the electron-emitting device, and (2) the device current I. It is determined by multiplication with the ratio of emission current that flows (emission efficiency).

  In the method described in Patent Document 1, when the emission efficiency is deteriorated due to a change over time, the applied voltage V is controlled to increase the element current I in order to set the emission current as a reference value even if the IV characteristic does not change. . As a result, the current flowing through the scanning line increases and the amount of voltage drop increases, so that smear deteriorates.

  Even if smear can be suppressed by the methods described in Patent Documents 2 and 3 at an early stage, image quality deterioration due to smear becomes conspicuous as time passes. Smear is a phenomenon that can be detected more significantly than a change in luminance of the entire screen, and its suppression is desired.

  In Patent Document 1, since an image is displayed by modulating the voltage application time, the applied voltage is controlled so that a specific current value is detected and matched with the reference value. However, in this method, when an image is displayed by voltage amplitude modulation of the data voltage shown in FIG. 11, when the slope α of the IV characteristic shown in FIG. 9 changes with time, an image corresponding to a specific current value is displayed. Aside from the data, a change in luminance occurs in other image data.

  The object of the present invention is to prevent the luminance from being changed even when the electron-emitting device changes with time, and to prevent the luminance from changing, and to keep the voltage drop generated by the current flowing through the scanning line constant. It is to prevent changes with time.

  Thereby, it is possible to provide a highly reliable image display device without image quality deterioration. Further, it is possible to provide an image display device that does not cause a change in luminance due to a change with time in the inclination α of the IV characteristic even when an image is displayed by voltage amplitude modulation.

  The present invention provides a plurality of scanning lines parallel to each other, a plurality of data lines orthogonal to the scanning lines, a back plate having a plurality of electron-emitting devices connected to the intersections of these lines, and the electron-emitting devices. A display panel comprising a front plate having a phosphor that emits light by electrons, scanning electrode selection means connected to the scanning lines, data electrode driving means connected to the data lines, and emission from the electron-emitting devices In the image display device comprising high voltage means for accelerating electrons and irradiating the phosphor, scanning line current detection means for detecting a scanning line current flowing from the scanning electrode selection means to the scanning line, and the scanning line Scanning electrode voltage correction means for correcting a scanning line selection voltage output from the scanning electrode selection means so that the scanning line current becomes a predetermined value based on a detection result of the current detection means. To.

  Further, a scanning line current detecting means for detecting a scanning line current flowing from the scanning electrode selection means to the scanning line, and a current flowing through the electron-emitting device based on a detection result of the scanning line current detecting means corresponds to image data. As described above, the data electrode selection means includes voltage correction means for correcting the data voltage output.

  As described above, according to the present invention, even if the threshold voltage or the slope of the electron-emitting device changes with time by detecting the scanning line current and correcting one or both of the scanning selection voltage and the data voltage, the image data The device current can be changed according to the brightness, and the luminance change can be prevented.

  Further, the voltage drop generated by the current flowing in the scanning line can be made constant, and the smear can be prevented from being deteriorated with time. Therefore, an image display device with high reliability and high image quality can be provided.

  In a display in which conventional electron-emitting devices are arranged in a matrix, smear occurs due to changes in the electron source over time and temperature characteristics, affecting the quality of the displayed image. The present invention is applied to a conventional matrix display. This makes it possible to display a suitable image. The present invention is also effective for an image display device using cold cathode elements such as metal / insulating film / metal type, field emission type, and surface conduction type.

  Embodiments of the present invention will be described below with reference to the drawings.

  An image display apparatus according to the present invention will be described with reference to FIGS. FIG. 1 is a circuit configuration diagram of the present embodiment. FIGS. 2A and 2B are diagrams for explaining the change with time of the IV characteristic of the electron-emitting device.

  In FIG. 1, a power source 3 is a power source that supplies power to the scan electrode voltage correction circuit 16. The detection resistor 1 detects a scanning line current that flows from the power source 3 into the scanning line selected through the scanning electrode voltage correction circuit 16 and the scanning electrode selection circuit 30.

  The adder / subtractor 5 inputs the potential across the detection resistor 1 and outputs an output signal 12 proportional to the voltage difference across the detection resistor 1. The output signal 12 is converted into digital current detection data 8 by the analog-digital (A / D) converter 2 and input to the voltage correction circuit 6.

  The voltage correction circuit 6 generates a correction signal 10 for correcting the output voltage of the scan electrode voltage correction circuit 16. The scan electrode voltage correction circuit 16 uses the correction signal 10 to correct the scan selection voltage output from the scan electrode selection circuit 30 to a predetermined voltage value.

  The voltage correction circuit 6 generates data electrode drive data 11 using the image data 207 and current detection data 8 input from the timing controller and inputs the data electrode drive data 11 to the data electrode drive circuit 7.

  The detection resistor 1, the A / D converter 2, and the adder / subtractor 5 constitute a scanning line current detection circuit 20. 7, 30, 207, 211, 212, 215, and 220 are the same as those in FIG.

  FIGS. 2A and 2B are diagrams for explaining different temporal changes in the IV characteristics of the electron-emitting device. In FIG. 2A, the threshold voltage representing the parallel movement of the IV characteristic in the voltage axis direction changes from Vth to Vth ′. The scan selection voltage output from the scan electrode selection circuit 30 is corrected so as to compensate for the change over time in the threshold voltage of the electron-emitting device.

  This correction will be described. In FIG. 1, image data 207 in which a voltage applied to a predetermined number of electron-emitting devices becomes a threshold voltage Vth is input to the voltage correction circuit 6. The voltage correction circuit 6 scans the current detection data 8 obtained from the scan line current detection circuit 20 and the scan line current value obtained from the image data 207 (specifically, electron emission that emits electrons at the threshold current value Ith). By comparing the number of elements in the scanning line direction and the threshold current value Ith), a correction signal 10 representing the applied voltage Vth ′ necessary for setting the element current to Ith is generated. Using this correction signal 10, the scan electrode correction circuit 16 corrects the scan selection voltage. As a result, even if the threshold voltage of the electron-emitting device changes from Vth to Vth ′, the device current of the electron-emitting device becomes a constant Ith.

Further, as shown in FIG. 2B, in the electron-emitting device, the logarithmic slope of the device current I with respect to the applied voltage V changes with time from α to α ′. The data voltage is corrected so as to correct such a change in inclination.

  This correction will be described. In FIG. 1, image data 207 in which the voltage applied to the electron-emitting device is other than the threshold voltage Vth is sequentially input to the voltage correction circuit 6. The voltage correction circuit 6 obtains the inclination α ′ from the current detection data 8 sequentially obtained from the scanning line current detection circuit 20 and generates the data electrode drive data 11 obtained by multiplying the image data 207 by α / α ′. Using the data electrode drive data 11, the data electrode drive circuit 7 outputs a data voltage to the display panel 215. As a result, the data voltage is corrected to α / α ′ times so as to correspond to the image data 207, so that the element current corresponding to the image data 207 is changed even if the slope of the IV characteristic of the electron-emitting device changes with time. It becomes.

  2A and 2B, the scanning selection voltage and the data voltage are corrected at the same time when the time-dependent changes of the electron-emitting devices exist simultaneously.

  As described above, according to the present embodiment, in a display in which electron-emitting devices are arranged in a matrix, an electron-emitting device is detected by detecting a scanning line current and correcting one or both of a scanning selection voltage and a data voltage. Even if the threshold voltage or inclination of the film changes with time, the device current can be set according to the image data, and the change in luminance can be prevented.

  Further, the voltage drop due to the current flowing in the scanning line can be made constant, and the smear can be prevented from being deteriorated with time. Therefore, an image display device with high reliability and high image quality can be provided.

An image display apparatus according to the present invention will be described with reference to FIG. In this embodiment, the on-resistance Ron of the selection switch SHi (i = 1 to n) of the scan electrode selection circuit 30 and the image data 207 are displayed.
Even when a voltage drop occurs due to the current flowing in response to the scan selection voltage, when the scan selection voltage output to the scan electrode Si (i = 1 to n) is driven to be a predetermined reference voltage, The reference current value is corrected so that the device current does not change even if the threshold voltage changes with time.

  FIG. 3 is a circuit configuration diagram of the present embodiment, and only two scanning lines and a circuit for driving them are shown for ease of explanation. In FIG. 3, reference numerals 2011 to 2014 in the display panel 215 denote electron emitting elements, and 2031 to 2034 denote scanning line resistances corresponding to one pixel. Scan electrode selection circuit 30 includes feedback switches SF1 and SF2 for monitoring the voltages of scan electrodes S1 and S2. The scan electrode voltage correction circuit 16 includes a negative feedback amplifier 13 and an adder 15.

  The voltage of the scan electrode S1 or S2 is input to the negative phase input terminal of the negative feedback amplifier 13 via the feedback switch SF1 or SF2. Power is supplied from the power supply 3 to the power supply terminal 14 of the negative feedback amplifier 13.

  The scanning line current is supplied from the power supply 3 to the display panel 215 via the output element in the negative feedback amplifier 13 and the scan selection switch SH1 or SH2, and is connected between the power supply terminal 14 of the negative feedback amplifier 13 and the power supply 3. The detected resistance 1 is detected.

  The adder 15 adds the voltage of the reference voltage source 211 and the correction signal 10 generated by the voltage correction circuit 6 to generate a reference scanning selection voltage Vref and inputs it to the positive phase input terminal of the negative feedback amplifier 13. .

  First, immediately after turning on the power of the image display device, image data 207 corresponding to an image pattern for detection having all black or a specific gradation is input to the voltage correction circuit 6. Based on the image data 207, the voltage correction circuit 6 generates the correction signal 10 in the same manner as in the first embodiment. Using this correction signal 10, the adder 5 generates a reference scanning selection voltage Vref.

  Next, a normal state in which a moving image is displayed is set. When the scan selection switch SH1 is selected in the first horizontal scanning period, the scan selection switch SH1 and the feedback switch SF1 are turned on, the non-selection switch SL1 is turned off, and the scan selection voltage is applied to the scan electrode S1. . Note that the scan selection switch SH2 and the feedback switch SF2 are off, the non-selection switch SL2 is on, and a scan non-selection voltage is applied to the scan electrode S2.

  In the next horizontal scanning period, the scanning selection switch SH2 and the feedback switch SF2 are turned on, the non-selection switch SL2 is turned off, and the selection voltage is applied to the scanning electrode S2. Note that the scan selection switch SH1 and the feedback switch SF1 are off, the non-selection switch SL1 is on, and a scan non-selection voltage is applied to the scan electrode S1.

  In each horizontal scanning period, the scanning selection voltage output to the scanning electrode becomes equal to the reference scanning selection voltage Vref input to the positive phase input terminal of the negative feedback amplifier 13 by the negative feedback operation. Even if a voltage drop occurs due to the on-resistance Ron of the scanning selection switch and the current flowing according to the image data 207, the voltage of the scanning line does not change.

  Since the time-dependent change in the electron source characteristics is a gradual change, the element current change due to the threshold voltage change is only generated just by generating the reference scan selection voltage Vref immediately after the image display apparatus is turned on. It can be sufficiently prevented.

  According to this embodiment, in a display in which electron-emitting devices are arranged in a matrix, even if a voltage drop occurs due to the ON resistance of the selection switch of the scan electrode selection circuit and the current flowing according to the image data, the scan selection voltage is It becomes a predetermined reference voltage. That is, by detecting the scanning line current and correcting the initial reference voltage, it is possible to prevent smear due to a voltage drop and to cope with image data even if the threshold voltage of the electron-emitting device changes with time. It can be an element current, and a luminance change can be prevented. Therefore, an image display device with high reliability and high image quality can be provided.

  An image display apparatus according to the present invention will be described with reference to FIGS. 4, 5, and 6. 4 is a circuit configuration diagram of this embodiment, and FIGS. 5 and 6 are operation waveform diagrams of FIG. 4, the same reference numerals as those in FIG. 3 denote the same components.

  In FIG. 4, in order to detect the current of the reference scanning line in the non-display area 217 of the display panel 215, the electron-emitting device connected to the intersection of the reference scanning electrode S0 and the reference scanning line and the data line 2009 and 2010 are provided.

  The number of electron-emitting devices connected to the reference scanning line is the same as the number of horizontal pixels in the display area 218. A detection resistor 1 is provided between the reference scan electrode S0 and the scan selection switch SH0. SF0 is a feedback switch, and SL0 is a non-selection switch. Other configurations are the same as those in FIG.

  Next, the operation will be described. First, in the horizontal scanning period of the period T0 shown in FIG. 5, the drive pulse (VS0) 17 is applied to the reference scanning electrode S0, and the reference scanning electrode S0 is driven. The vertical display period starts at time Tstv shown in FIG. 5, the scanning electrode S1 is driven in the horizontal scanning period T1 by the driving pulse (VS1) 18, and the scanning electrode S2 is horizontally scanned by the next driving pulse (VS2) 19. After the driving in the period T2, line sequential driving is performed thereafter.

  For each vertical scanning period, the reference scanning electrode S0 is selected, and scanning line current detection and comparison operation in the voltage correction circuit 6 are performed. The image data input for scanning line current detection is changed every two vertical scanning periods.

  In the first vertical scanning period, the image data 207 is inputted so that the applied voltage to the electron-emitting device becomes the threshold voltage, the scanning line current at this time is detected, and the reference voltage that becomes the scanning selection voltage The value is corrected to compensate for the change in the threshold voltage of the electron-emitting device.

  In the subsequent second vertical scanning period, image data 207 is input so that the voltage applied to the electron-emitting device is other than the threshold voltage, and the scanning line current at this time is detected and the data voltage is corrected. Thus, a change in the slope of the IV characteristic of the electron-emitting device is compensated.

  FIG. 6 is a detailed waveform diagram of the drive pulse 17 for the reference scan electrode S0 in the outside display area 217 and the drive pulses 18 and 19 for the scan electrodes in the display area 218. The rising speed of the drive pulse 17 of the reference scan electrode S0 is determined by the combined resistance obtained by adding the resistance value of the detection resistor 1 to the ON resistance Ron of the scan selection switch SH0 and the capacitance connected to the scan line. Therefore, the scanning line current is detected in a period Tsp after the drive pulse 17 reaches a steady value.

  On the other hand, the rising speed of the drive pulses 18 and 19 of the scan electrodes S1 and S2 is determined by the on-resistance Ron of the scan selection switch and the capacitance connected to the scan line. Therefore, the rising delay of the scan electrode drive waveform due to the detection resistor 1 in the display region 218 does not occur. Therefore, the luminance reduction related to the detection resistor 1 does not occur.

  According to the present embodiment, the same effects as those of the first and second embodiments can be obtained. Further, since the scanning line current is detected using the electron emitting element provided outside the display region, the scanning line current can be detected in a normal state in which a moving image is projected. It is possible to perform correction following the temperature change.

  Furthermore, there is no waveform delay related to the detection resistor, and no luminance reduction occurs. Therefore, an image display apparatus with high reliability and high image quality can be provided.

  An image display apparatus according to the present invention will be described with reference to FIG. FIG. 7 is a circuit configuration diagram of the present embodiment. 7, the same reference numerals as those in FIG. 4 denote the same components.

  In FIG. 7, the scanning line current is detected from the voltage drop amount of the on-resistance Ron of the scanning selection switch SH0. That is, by inputting the output voltage and the negative phase input voltage of the negative feedback amplifier 13 to the adder / subtractor 5, the adder / subtractor 5 outputs an output signal proportional to the product of the on-resistance Ron of the scan selection switch SH0 and the scan line current. 12 is output. The output signal 12 is converted into digital current detection data 8 by using the A / D converter 2 and input to the voltage correction circuit 6.

  As in the third embodiment shown in FIG. 4, the scanning electrode S0 and the electron-emitting devices 2009 and 2010 connected to the scanning line and the data line are provided in the display outside region 217 of the display panel 215 for detecting the scanning line current. Provided for each vertical scanning period, scanning line current detection and comparison calculation in the voltage correction circuit 6 are performed to compensate for changes in threshold voltage and inclination with time.

  According to the present embodiment, the same effects as those of the third embodiment can be obtained, and the detection resistor 1 in the scanning line current detection circuit 20 is not necessary. Therefore, a low-cost, high-reliability, high-quality image display device can be provided.

  In this embodiment, the image data corresponding to the detection image pattern having all black or a specific gradation is obtained in the period from immediately after the power is turned on to the normal display state without providing the outside display area 217. Input can detect and correct the scanning line current.

  In Examples 1 to 4, even if the IV characteristic of the electron-emitting device changes with time, the change in luminance and smear with time is suppressed by setting the device current according to the image data. However, it is not possible to prevent a change in luminance when the emission efficiency of the amount of electrons emitted from the electron-emitting device changes.

  When a change in luminance due to a change in emission efficiency over time becomes a problem, any of the first to fourth examples is used to suppress the change over time due to the IV characteristic first, and then, for example, in the high-voltage circuit 220, the emission current is reduced. This can be solved by detecting and correcting the application time of the data voltage to the electron-emitting device or the output voltage value of the high-voltage circuit so that the emission current matches a preset reference value.

  In the second to fourth embodiments, the voltage of the scan electrode Si (i = 1 to n) serving as the output point of the scan electrode selection circuit 30 is fed back, and the transistors constituting the selection switch SHi (i = 1 to n) are fed back. By controlling the voltage input to the source, the scanning selection voltage is set to a predetermined reference voltage regardless of the voltage drop at the selection switch, but the voltage input to the gate of the transistor constituting the selection switch is controlled. Thus, the scanning selection voltage may be set as the predetermined reference voltage regardless of the voltage drop at the selection switch.

  Further, in the second to fourth embodiments, calculation parameters are generated based on the current detection data 8, the data electrode driving data 11 is calculated from the calculation parameters and the image data 207, and scanning lines determined according to the image data 207. By correcting the data voltage so as to compensate for the voltage drop of each part of the device, even if the IV characteristics of the electron-emitting device change over time, the voltage drop caused by the scanning line resistance is suppressed, and the image quality due to smearing is suppressed. Deterioration can be prevented.

The circuit block diagram of Example 1 of this invention. FIG. 4 is a time-dependent change diagram of electron-emitting device IV characteristics for explaining the first embodiment. The circuit block diagram of Example 2 of this invention. The circuit block diagram of Example 3 of this invention. FIG. 6 is an operation waveform diagram for explaining the third embodiment. FIG. 6 is an operation waveform diagram for explaining the third embodiment. The circuit block diagram of Example 4 of this invention. The structural model figure of the backplate which has arrange | positioned the electron-emitting element in matrix form. The voltage-current characteristic view of an electron-emitting device. The block diagram of the drive circuit of the display panel using an electron emission element. FIG. 11 is an operation waveform diagram for explaining the operation of the drive circuit of FIG. 10.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Detection resistor, 2 ... Analog-digital converter, 3 ... Power supply, 5 ... Adder / subtractor, 6 ... Voltage correction circuit, 7 ... Data electrode drive circuit, 8 ... Current detection data, 10 ... Correction signal, 11 ... Data electrode Drive data, 12 ... Output signal, 13 ... Negative feedback amplifier, 14 ... Power input terminal, 15 ... Adder, 16 ... Scanning electrode voltage correction circuit, 20 ... Scanning line current detection circuit, 30 ... Scanning electrode selection circuit,
DESCRIPTION OF SYMBOLS 201 ... Electron emission element, 202 ... Data line, 203 ... Scanning line, 204 ... Synchronization signal, 205 ... Timing controller, 207 ... Image data, 208 ... Control signal, 210 ... Image signal, 211 ... First reference voltage source, 212 ... second reference voltage source, 214 ... control signal, 215 ... display panel, 220 ... high voltage circuit,
2009-2014 ... Electron emitting elements, 2029-2034 ... Scanning line resistance corresponding to one pixel.

Claims (4)

A plurality of scanning lines parallel to each other, a plurality of data lines orthogonal to the scanning lines, a back plate having a plurality of electron-emitting devices connected to the intersections of these lines, and light emitted from electrons from the electron-emitting devices A display panel comprising a front plate having a phosphor; scanning electrode selection means connected to the scanning lines; data electrode driving means connected to the data lines; and electrons emitted from the electron-emitting devices are accelerated. In the image display device provided with a high-pressure means for irradiating the phosphor,
A scanning line current detection unit for detecting a scanning line current flowing from the scanning electrode selection unit to the scanning line; and the scanning electrode selection so that the scanning line current becomes a predetermined value based on a detection result of the scanning line current detection unit. And an electrode voltage correcting means for correcting the scanning line selection voltage output by the means. A plurality of scanning lines parallel to each other, a plurality of data lines orthogonal to the scanning lines, a back plate having a plurality of electron-emitting devices connected to the intersections of these lines, and light emitted from electrons from the electron-emitting devices A display panel comprising a front plate having a phosphor; scanning electrode selection means connected to the scanning lines; data electrode driving means connected to the data lines; and electrons emitted from the electron-emitting devices are accelerated. In the image display device provided with a high-pressure means for irradiating the phosphor,
A scanning line current detection unit that detects a scanning line current flowing from the scanning electrode selection unit to the scanning line, and a current that flows through the electron-emitting device based on a detection result of the scanning line current detection unit corresponds to image data. An image display device comprising voltage correction means for correcting the data voltage output from the data electrode selection means.   The back plate includes a scanning line provided on at least one side outside the display area, and a plurality of electron-emitting devices connected between the scanning line and the data line, and current flowing through the scanning line is The image display device according to claim 1, wherein the scanning line current detection means detects.   The image display apparatus according to claim 1, wherein the scanning line current detection unit detects the scanning line current in a period immediately after the power is turned on.

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