JP2015222278A - Method for driving image display device, image display device, and image display system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To generate light emission capable of detecting coordinates from a position close to and a position away from an image display surface.SOLUTION: One field is configured with a plurality of subfields including: a proximity y coordinate detection subfield SFy1 in which an operation to apply a y coordinate detection pulse to a first number of scanning electrodes at the same time while keeping a y coordinate detection voltage applied to a data electrode is successively performed; a remote y coordinate detection subfield SFy2 in which an operation to apply a y coordinate detection pulse to a second number of scanning electrodes greater than the first number at the same time while keeping a y coordinate detection voltage applied to a data electrode is successively performed; a proximity x coordinate detection subfield SFx1 in which an operation to apply an x coordinate detection pulse to a third number of data electrodes at the same time while keeping an x coordinate detection voltage applied to a scanning electrode is successively performed; and a remote x coordinate detection subfield SFx2 in which an operation to apply an x coordinate detection pulse to a fourth number of data electrodes greater than the third number at the same time while keeping an x coordinate detection voltage applied to a scanning electrode is successively performed.

Description

  The present invention relates to an image display device driving method, an image display device, and an image display system capable of handwritten input using an electronic pen.

  A typical plasma display panel as a large-screen image display element includes a front substrate on which a plurality of display electrode pairs including a pair of scan electrodes and sustain electrodes are formed, and a rear substrate on which a plurality of data electrodes are formed. A large number of discharge cells are formed between them. Then, ultraviolet rays are generated by gas discharge in the discharge cell, and the phosphors of red, green and blue colors are excited and emitted by the ultraviolet rays to perform color display.

  As a method for driving a plasma display panel, a subfield method in which one field period is composed of a plurality of subfields and an image is displayed by a combination of subfields that emit light is generally used. Each subfield has an initialization period, an address period, and a sustain period. In the initializing period, initializing discharge is generated, and wall charges necessary for address discharge are formed. In the address period, address discharge is selectively generated in the discharge cells in accordance with the image to be displayed, and wall charges necessary for the sustain discharge are formed. In the sustain period, a sustain pulse is alternately applied to the scan electrode and the sustain electrode to generate a sustain discharge, and the phosphor layer of the corresponding discharge cell emits light.

  In recent years, an application as an electronic blackboard that can input characters, pictures, and the like from an image display surface, such as a blackboard or a whiteboard, using such a plasma display panel has been studied. For example, in Patent Document 1, a position coordinate detection period is provided in one field only at the time of position coordinate detection, light emission for position coordinate detection is generated within this period, and the position coordinates are detected at the timing when the light emission is detected by an electronic pen. A method of detecting is described.

JP 2001-318765 A

  However, the discharge for detecting the position coordinates is a slightly weaker discharge than the sustain discharge for displaying an image, and the luminance of the light emission accompanying the discharge is slightly lower. Therefore, in order to receive the light emission of the discharge for detecting the position coordinates, it is necessary to use the electronic pen in contact with the image display surface of the image display device or close to the image display surface.

  On the other hand, when an image display system capable of drawing in a presentation or the like is used, there is a demand for drawing from a position far from the image display surface of the image display device or displaying a cursor. However, there has been a problem that the emission of discharge for detecting position coordinates cannot be detected from a position away from the image display surface.

  SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and a method for driving an image display device that generates light emission capable of detecting coordinates from a position in contact with or close to the image display surface and a position away from the image display surface. An object is to provide a display device and an image display system capable of drawing using an electronic pen.

  To achieve the above object, the present invention provides an image having a plurality of scan electrodes and sustain electrodes extending in a first direction, and a plurality of data electrodes extending in a second direction intersecting the first direction. An image display device driving method using a display element, wherein an image display subfield for displaying an image for one field period, and a first number of scan electrodes while a y-coordinate detection voltage is applied to a data electrode Y-coordinate detection subfield for proximity that sequentially applies the operation of applying y-coordinate detection pulses simultaneously to the second number of scan electrodes larger than the first number while applying the y-coordinate detection voltage to the data electrodes. Remote y-coordinate detection subfield for sequentially performing the operation of applying the coordinate detection pulse, and the operation of simultaneously applying the x-coordinate detection pulse to the third number of data electrodes while applying the x-coordinate detection voltage to the scan electrodes. The proximity x-coordinate detection subfield to be performed and the remote operation for sequentially applying the x-coordinate detection pulses to the fourth number of data electrodes larger than the third number while the x-coordinate detection voltage is applied to the scan electrodes. and a plurality of subfields including an x-coordinate detection subfield. By this method, it is possible to provide a driving method of an image display device that generates light emission capable of detecting coordinates from a position close to the image display surface and a position away from the image display surface.

  The present invention also provides an image using an image display element having a plurality of scan electrodes and sustain electrodes extending in a first direction, and a plurality of data electrodes extending in a second direction intersecting the first direction. A driving method of a display device, wherein one field period is applied to an image display subfield for displaying an image and a scan electrode of “1” which is a first number while a y-coordinate detection voltage is applied to a data electrode. A proximity y-coordinate detection subfield that sequentially performs an operation of applying a y-coordinate detection pulse, and a second number of scan electrodes that is greater than the first number “1” while the y-coordinate detection voltage is applied to the data electrodes. And a remote y-coordinate detection subfield for sequentially applying the y-coordinate detection pulse to the x-coordinate detection pulse, and the x-coordinate detection pulse to the data electrode “1” which is the third number while the x-coordinate detection voltage is applied to the scan electrode. Operation to apply The x-coordinate detection pulse is applied to the fourth number of data electrodes larger than “1”, which is the third number, while the x-coordinate detection subfield for proximity is sequentially applied and the x-coordinate detection voltage is applied to the scan electrodes. And a remote x-coordinate detection subfield that sequentially performs operations, and a plurality of subfields. This method can also provide a driving method of an image display device that generates light emission capable of detecting coordinates from a position close to the image display surface and a position away from the image display surface.

  The present invention also provides an image display element having a plurality of scan electrodes and sustain electrodes extending in a first direction, and a plurality of data electrodes extending in a second direction intersecting the first direction, and one field period. An image display device comprising a drive circuit configured by a plurality of subfields and driving an image display element, wherein the drive circuit includes an image display subfield for displaying an image for one field period, and a data electrode The proximity y-coordinate detection subfield that sequentially applies the y-coordinate detection pulse to the first number of scan electrodes while applying the y-coordinate detection voltage to the first electrode, and the y-coordinate detection voltage applied to the data electrodes. A remote y-coordinate detection subfield for sequentially performing an operation of simultaneously applying y-coordinate detection pulses to a second number of scan electrodes greater than one, and an x-coordinate detection voltage applied to the scan electrodes A proximity x-coordinate detection subfield for sequentially performing an operation of simultaneously applying x-coordinate detection pulses to the three data electrodes, and a fourth number greater than the third number while the x-coordinate detection voltage is applied to the scan electrodes. The image display element is driven by a plurality of subfields including a remote x-coordinate detection subfield that sequentially performs an operation of simultaneously applying an x-coordinate detection pulse to the data electrodes. With this configuration, it is possible to provide an image display device that generates light emission capable of detecting coordinates from a position close to the image display surface and a position away from the image display surface.

  The present invention also provides an image display element having a plurality of scan electrodes and sustain electrodes extending in a first direction, and a plurality of data electrodes extending in a second direction intersecting the first direction, and one field period. An image display device comprising a drive circuit configured by a plurality of subfields and driving an image display element, wherein the drive circuit includes an image display subfield for displaying an image for one field period, and a data electrode A y-coordinate detection subfield for proximity that sequentially applies an y-coordinate detection pulse to the first number “1” scan electrode while the y-coordinate detection voltage is applied to the data electrode, and a y-coordinate detection voltage to the data electrode. A remote y-coordinate detection subfield that sequentially applies an y-coordinate detection pulse to a second number of scan electrodes that is greater than the first number “1” while being applied, and x-coordinate detection to the scan electrodes. A proximity x-coordinate detection subfield that sequentially applies an x-coordinate detection pulse to the third number “1” data electrode while applying a pressure, and the x-coordinate detection voltage applied to the scan electrode. And a remote x-coordinate detection subfield that sequentially performs an operation of simultaneously applying an x-coordinate detection pulse to a fourth number of data electrodes that is greater than “1” that is the number of 3. The image display element is driven. Also with this configuration, it is possible to provide an image display device that generates light emission capable of detecting coordinates from a position close to the image display surface and a position away from the image display surface.

  The present invention also provides an image display device according to the above, an electronic pen that calculates coordinates on the display screen of the image display device that receives and indicates light emission of the image display device, and a drawing signal based on the coordinates calculated by the electronic pen. The electronic pen calculates the y coordinate using the light emission of the proximity y coordinate detection subfield when receiving the light emission of the proximity y coordinate detection subfield. If the light emission of the remote y coordinate detection subfield is received without receiving the light emission of the proximity y coordinate detection subfield, the y coordinate is calculated using the light emission of the remote y coordinate detection subfield, and the proximity x When the light emission of the coordinate detection subfield is received, the x coordinate is calculated by using the light emission of the proximity x coordinate detection subfield, and the light emission of the proximity x coordinate detection subfield is not received. If you receive emission target detection subfield and calculates the x-coordinate with the emission of a remote for x-coordinate detection subfield. With this configuration, an image display device that generates light emission capable of detecting coordinates from a position close to the image display surface and a position away from the image display surface, and an image display system capable of drawing using an electronic pen are provided. Can do.

  According to the present invention, a driving method of an image display device that generates light emission capable of detecting coordinates from a position close to the image display surface and a position away from the image display surface, an image display device, and drawing using an electronic pen It is possible to provide a possible image display system.

It is a disassembled perspective view of the panel of the image display system in embodiment of this invention. It is an electrode array figure of the panel of the image display system. It is a drive voltage waveform figure applied to the panel of the image display system. It is a drive voltage waveform figure applied to the panel of the image display system. It is a circuit block diagram of the image display system. It is a schematic diagram explaining the position coordinate detection method of the image display system. It is a timing chart explaining the position coordinate detection method of the image display system. It is a schematic diagram explaining the position coordinate detection method of the image display system. It is a timing chart explaining the position coordinate detection method of the image display system. It is a schematic diagram which shows an example of drawing of the image display system. It is another drive voltage waveform figure applied to the panel of the image display system.

  Hereinafter, an image display system according to an embodiment of the present invention will be described with reference to the drawings, taking as an example an image display system using a plasma display panel (hereinafter abbreviated as “panel”).

(Embodiment)
First, the panel and its driving method will be described.

  FIG. 1 is an exploded perspective view of panel 10 of the image display system according to the embodiment of the present invention. On the glass front substrate 11, a plurality of display electrode pairs 14 made up of scanning electrodes 12 and sustaining electrodes 13 are formed. A dielectric layer 15 is formed so as to cover the display electrode pair 14, and a protective layer 16 is formed on the dielectric layer 15. A plurality of data electrodes 22 are formed on the rear substrate 21, a dielectric layer 23 is formed so as to cover the data electrodes 22, and a grid-like partition wall 24 is formed thereon. Then, on the side surface of the partition wall 24 and the dielectric layer 23, any one of the phosphor layer 25R that emits red light, the phosphor layer 25G that emits green light, and the phosphor layer 25B that emits light of each blue color. 25 is provided.

  The front substrate 11 and the rear substrate 21 are arranged to face each other so that the display electrode pair 14 and the data electrode 22 intersect with each other with a minute discharge space interposed therebetween, and the outer periphery thereof is sealed with a sealing material such as glass frit. Has been. A discharge gas is sealed in the discharge space. The discharge space is partitioned into a plurality of sections by barrier ribs 24, and discharge cells are formed at intersections of scan electrode 12, sustain electrode 13, and data electrode 22, respectively. These discharge cells discharge and emit light to display an image.

  FIG. 2 is an electrode array diagram of panel 10 of the image display system in the embodiment of the present invention. The panel 10 includes n scan electrodes SC1 to SCn (scan electrode 12 in FIG. 1) and n sustain electrodes SU1 to SUn (sustain electrode 13 in FIG. 1) extending in the first direction. The m data electrodes D1 to Dm (data electrode 22 in FIG. 1) extending in the second direction intersecting with the first direction are arranged. A discharge cell is formed at a portion where one pair of scan electrode SCi (i = 1 to n) and sustain electrode SUi intersects one data electrode Dj (j = 1 to m), and the discharge cell is in the discharge space. M × n are formed. Here, the three discharge cells formed at the intersection of the three adjacent data electrodes and the pair of display electrodes are a red subpixel, a green subpixel, and a blue subpixel. These three color sub-pixels constitute one pixel. Therefore, for example, if the panel 10 is a high definition panel having 1080 × 1920 pixels, n = 1080 and m = 1920 × 3 = 5760. Hereinafter, for convenience, the first direction is referred to as a row direction, and the second direction is referred to as a column direction.

  Next, the drive voltage waveform of the image display apparatus will be described. In the present embodiment, one field period is composed of a plurality of image display subfields for displaying an image and a plurality of coordinate detection subfields for detecting coordinates.

  First, details of the image display subfield will be described. The image display subfield has a predetermined luminance weight, and an image is displayed by controlling light emission / non-light emission for each discharge cell in each image display subfield.

  The image display subfields in the present embodiment are eight subfields SF1 to SF8 having an initialization period, a writing period, and a sustain period. The luminance weights of the subfields SF1 to SF8 are, for example, (1, 34). 21, 13, 8, 5, 3, 2). However, the subfield configuration such as the number of subfields and the luminance weight is not limited to the above.

  FIG. 3 is a drive voltage waveform diagram applied to panel 10 of the image display system according to the embodiment of the present invention. Drive voltage applied to each electrode of panel 10 in subfields SF1 to SF3 among the image display subfields. The waveform is shown.

  In initialization period Pi of subfield SF1, voltage 0 (V) is applied to data electrodes D1 to Dm, voltage 0 (V) is applied to sustain electrodes SU1 to SUn, and voltage from voltage Vi1 is applied to scan electrodes SC1 to SCn. An upward ramp voltage that rises to Vi2 is applied. Next, the voltage 0 (V) is applied to the data electrodes D1 to Dm, the voltage Ve is applied to the sustain electrodes SU1 to SUn, and the downward ramp voltage descending from the voltage 0 (V) to the voltage Vi4 is applied to the scan electrodes SC1 to SCn. Apply.

  Then, a weak initializing discharge occurs in all the discharge cells, the wall voltage on scan electrodes SC1 to SCn and the wall voltage on sustain electrodes SU1 to SUn are weakened, and the wall voltage on data electrodes D1 to Dm is written. It is adjusted to a value suitable for operation. Note that the luminance of light emission due to weak initialization discharge is low.

  In the subsequent address period Pw, voltage 0 (V) is applied to data electrodes D1 to Dm, voltage Ve is applied to sustain electrodes SU1 to SUn, and voltage Vc is applied to scan electrodes SC1 to SCn.

  Next, a scan pulse of voltage Va is applied to scan electrode SC1 in the first row, and voltage is applied to data electrode Dk (k = 1 to m) of the discharge cell to be emitted in the first row among data electrodes D1 to Dm. Vd write pulse is applied. Then, an address discharge is generated in the discharge cells in the first row to which the address pulse is applied, and wall voltage is accumulated on scan electrode SC1 and sustain electrode SU1. Thus, the address operation is performed in the discharge cells that should emit light in the first row. On the other hand, the address operation is not performed in the discharge cells to which the address pulse is not applied. Next, a scan pulse is applied to scan electrode SC2 in the second row, and an address pulse is applied to data electrode Dk of the discharge cell to be emitted in the second row among data electrodes D1 to Dm. Then, address discharge occurs in the discharge cells in the second row to which the address pulse is applied.

  Similarly, scan pulses are sequentially applied to scan electrodes SC3 to SCn and address pulses are applied to data electrodes Dk of the discharge cells to be emitted, and address discharge is performed in the discharge cells to be emitted in the third to nth rows. Are generated sequentially. The address discharge generated at this time is a slightly weaker discharge than the sustain discharge described later, and the luminance of light emission accompanying the discharge is also slightly lower.

  In the subsequent sustain period Ps, the voltage 0 (V) is applied to the data electrodes D1 to Dm. A sustain pulse of voltage Vs is applied to scan electrodes SC1 to SCn, and voltage 0 (V) is applied to sustain electrodes SU1 to SUn. Then, a sustain discharge occurs in the discharge cell in which the address discharge has occurred. Then, the polarity of the wall voltage on scan electrode SCi and sustain electrode SUi is reversed. In the discharge cells that have not performed the address operation, no sustain discharge occurs, and the wall voltage at the end of the initialization period Pi is maintained.

  Subsequently, voltage 0 (V) is applied to scan electrodes SC1 to SCn, and a sustain pulse is applied to sustain electrodes SU1 to SUn. Then, the sustain discharge occurs again in the discharge cell that has caused the sustain discharge. Then, the polarities of the wall voltage on scan electrode SCi and the wall voltage on sustain electrode SUi are reversed. Similarly, sustain pulses of the number corresponding to the luminance weight are alternately applied to scan electrodes SC1 to SCn and sustain electrodes SU1 to SUn, and sustain discharge is continuously generated in the discharge cells that have caused address discharge in address period Pw. Let The sustain discharge generated at this time is a strong discharge, and the luminance of light emission accompanying the discharge is high.

  At the end of sustain period Ps, voltage 0 (V) is applied to data electrodes D1 to Dm, voltage 0 (V) is applied to sustain electrodes SU1 to SUn, and voltage 0 (V) is applied to scan electrodes SC1 to SCn. An upward ramp voltage that rises from 1 to the voltage Vr is applied. Then, a weak erasing discharge is generated in the discharge cell that has generated the sustain discharge, and the wall voltage on scan electrode SCi and on sustain electrode SUi is weakened while the wall voltage on data electrode Dk remains.

  In initialization period Pi of subfield SF2, voltage 0 (V) is applied to data electrodes D1 to Dm, voltage Ve is applied to sustain electrodes SU1 to SUn, and voltage from voltage 0 (V) is applied to scan electrodes SC1 to SCn. A downward ramp voltage that falls to Vi4 is applied. Then, a weak initializing discharge is generated in the discharge cell that has caused the sustain discharge in the immediately preceding subfield SF1, the wall voltage on scan electrode SCi and the wall voltage on sustain electrode SUi are weakened, and the wall on data electrode Dk is weakened. The voltage is adjusted to a value suitable for the write operation. On the other hand, the discharge cells that have not caused the sustain discharge in the immediately preceding subfield SF1 are not discharged, and the wall voltage at the end of the initialization period Pi in the immediately preceding subfield SF1 is maintained.

  Since the operation in the writing period Pw of the subfield SF2 is the same as the operation in the writing period Pw of the subfield SF1, description thereof is omitted. The operation in the subsequent sustain period Ps is the same as the operation in the sustain period Ps of the subfield SF1 except for the number of sustain pulses. The operations of subfields SF3 to SF8 are the same as those of subfield SF2 except for the number of sustain pulses.

  Next, the coordinate detection subfield will be described. The coordinate detection subfield in the present embodiment includes a synchronization detection subfield, a proximity y coordinate detection subfield, a proximity x coordinate detection subfield, a remote y coordinate detection subfield, and a remote x coordinate detection subfield. With the field.

  The synchronization detection subfield is a subfield in which the electronic pen emits light to synchronize with the light emission timing of the panel 10, and has an initialization period, a writing period, and a synchronization detection period.

  The proximity y-coordinate detection subfield and the remote y-coordinate detection subfield are subfields that emit light for detecting the y-coordinate on the image display surface pointed to by the electronic pen. Both the initialization period and the y-coordinate detection are detected. It has a period and an erasing period. Here, the proximity y-coordinate detection subfield is a subfield that emits light for accurately detecting the y-coordinate at a position on or near the image display surface, and the remote y-coordinate detection subfield is an image display. This is a subfield that generates light for detecting the y-coordinate even from a distance some distance from the surface.

  The proximity x-coordinate detection subfield and the remote x-coordinate detection subfield are subfields that emit light for detecting the x-coordinate on the image display surface pointed to by the electronic pen. Both the initialization period and the x-coordinate detection are detected. It has a period and an erasing period. Here, the proximity x-coordinate detection subfield is a subfield that emits light for accurately detecting the x-coordinate at a position on or near the image display surface, and the remote x-coordinate detection subfield is an image display. This is a subfield that generates light for detecting the x-coordinate even from a distance some distance from the surface.

  Here, the coordinate in the row direction is the x coordinate, and the coordinate in the column direction is the y coordinate.

  FIG. 4 is a drive voltage waveform diagram applied to panel 10 of the image display system in the embodiment of the present invention, and shows drive voltage waveforms applied to each electrode of panel 10 in each of the coordinate detection subfields.

  In the initialization period Pi of the synchronization detection subfield SFo, the voltage 0 (V) is applied to the data electrodes D1 to Dm, the voltage Ve is applied to the sustain electrodes SU1 to SUn, and the voltage 0 (V) is applied to the scan electrodes SC1 to SCn. To the voltage Vi4 is applied. Then, the wall voltage on each electrode is adjusted to a value suitable for the write operation.

  In the address period Pw of the synchronization detection subfield SFo, the voltage 0 (V) is applied to the data electrodes D1 to Dm, the voltage Ve is applied to the sustain electrodes SU1 to SUn, and the voltage Vc is applied to the scan electrodes SC1 to SCn. Thereafter, an address pulse of voltage Vd is applied to data electrodes D1 to Dm, and a scan pulse of voltage Va is applied to scan electrodes SC1 to SCn. Then, address discharge occurs in all the discharge cells. In this embodiment, in order to shorten the driving time, a scan pulse is simultaneously applied to scan electrodes SC1 to SCn and an address pulse is simultaneously applied to data electrodes D1 to Dm, so that address discharge is simultaneously performed in all discharge cells. Is generated.

  After the address discharge has converged, the voltages of scan electrodes SC1 to SCn are returned to voltage Vc, and the voltages of data electrodes D1 to Dm are returned to voltage 0 (V).

  In the synchronization detection period Po of the synchronization detection subfield SFo, the synchronization detection pulse of the voltage Vso is applied to the scan electrodes SC1 to SCn and the sustain electrode at the time to1 after the time To0 has elapsed from the time to0 when the address discharge was last generated. A voltage 0 (V) is applied to SU1 to SUn, and synchronous detection discharge is generated in all the discharge cells. Next, at time to2 after time To1 has elapsed from time to1, voltage 0 (V) is applied to scan electrodes SC1 to SCn, and a synchronous detection pulse of voltage Vso is applied to sustain electrodes SU1 to SUn to detect synchronization again. Generate a discharge. Next, at time to3 after the lapse of time To2 from time to2, a synchronization detection pulse is applied to scan electrodes SC1 to SCn, and voltage 0 (V) is applied to sustain electrodes SU1 to SUn. Is generated. Subsequently, at time to4 after time To3 has elapsed from time to3, voltage 0 (V) is applied to scan electrodes SC1 to SCn and a synchronous detection pulse is applied to sustain electrodes SU1 to SUn, and a fourth synchronous detection discharge is performed. generate.

  Here, time To1, time To2, and time To3 are predetermined time intervals. As described later, synchronous detection is performed by detecting four discharges that occur at intervals of time To1, time To2, and time To3. The discharge is specified. In the present embodiment, time To0, time To1, time To2, and time To3 are, for example, 50 μs, 40 μs, 20 μs, and 30 μs, respectively. Note that the synchronous detection discharge itself generated at this time is a strong discharge similar to the sustain discharge, and the luminance of light emission accompanying the discharge is high.

  At the end of the synchronization detection period Po, the voltage 0 (V) is applied to the data electrodes D1 to Dm, the voltage 0 (V) is applied to the sustain electrodes SU1 to SUn, and the voltage 0 (V) is applied to the scan electrodes SC1 to SCn. ) To the voltage Vr, and the wall voltage on scan electrode SCi and sustain electrode SUi is weakened.

  In the initialization period Pi of the proximity y coordinate detection subfield SFy1, the voltage 0 (V) is applied to the data electrodes D1 to Dm, the voltage Ve is applied to the sustain electrodes SU1 to SUn, and the voltage 0 is applied to the scan electrodes SC1 to SCn. A downward ramp voltage that falls from (V) to voltage Vi4 is applied. Then, a weak initializing discharge occurs in all the discharge cells, and the wall voltage on each electrode is adjusted to a value suitable for the coordinate detection operation.

  In the y coordinate detection period Py1 of the proximity y coordinate detection subfield SFy1, an operation of simultaneously applying a y coordinate detection pulse to the first number of scan electrodes while applying the y coordinate detection voltage Vdy to the data electrodes D1 to Dm. Do it sequentially. In the following description, it is assumed that the first number is “1”, but the first number may be “2” or more.

  First, voltage 0 (V) is applied to data electrodes D1 to Dm, voltage Ve is applied to sustain electrodes SU1 to SUn, and voltage Vc is applied to scan electrodes SC1 to SCn.

  Next, the y coordinate detection voltage Vdy is applied to the data electrodes D1 to Dm. Then, a y-coordinate detection pulse of voltage Vay is applied to scan electrode SC1 in the first row. Then, discharge for y coordinate detection (y coordinate detection discharge) occurs in the discharge cells in the first row. Thus, the first pixel row emits light.

  Next, the y coordinate detection pulse is applied to the scan electrode SC2 in the second row while the y coordinate detection voltage Vdy is applied to the data electrodes D1 to Dm. Then, y coordinate detection discharge is generated in the discharge cells in the second row. Thus, the second pixel row emits light.

  Similarly, the y-coordinate detection pulses are sequentially applied to the scan electrodes SC3 to SCn while the y-coordinate detection voltage Vdy is applied to the data electrodes D1 to Dm, so that the third to nth pixel rows are sequentially emitted. .

  Thus, in the y coordinate detection period Py1 of the proximity y coordinate detection subfield SFy1, the y coordinate detection pulse is simultaneously applied to the first number of scan electrodes while the y coordinate detection voltage Vdy is applied to the data electrodes D1 to Dm. Perform operations sequentially. In the present embodiment, since the first number is “1”, the phrase “sequentially applying the y-coordinate detection pulse to the first number of scan electrodes simultaneously” is “one scan electrode. It goes without saying that the operation of applying the y-coordinate detection pulse is sequentially performed.

  Note that the y-coordinate detection discharge generated at this time is a discharge similar to the address discharge, which is slightly weaker than the sustain discharge, and the luminance of light emission accompanying the discharge is also slightly lower.

  In this way, in the y-coordinate detection period Py1, the horizontal line that emits light with the thickness of one pixel row moves pixel by pixel from the upper end to the lower end of the image display surface. Therefore, as will be described later, the y-coordinate of the image display surface pointed to by the electronic pen can be detected by receiving the light emission of the horizontal line with the electronic pen located near the image display surface and knowing the timing of the light emission.

  In the erasing period Pe of the proximity y-coordinate detection subfield SFy1, the voltage 0 (V) is applied to the data electrodes D1 to Dm, the voltage 0 (V) is applied to the sustain electrodes SU1 to SUn, and the scan electrodes SC1 to SCn are applied. An ascending ramp voltage that rises from voltage 0 (V) to voltage Vr is applied to generate a weak erase discharge in the discharge cell.

  The operation in the initialization period Pi of the proximity x-coordinate detection subfield SFx1 is the same as the operation in the initialization period Pi of the proximity y-coordinate detection subfield SFy1.

  In the x coordinate detection period Px1 of the proximity x coordinate detection subfield SFx1, the operation of simultaneously applying the x coordinate detection pulse to the third number of data electrodes while applying the x coordinate detection voltage Vax to the scan electrodes SC1 to SCn. Do it sequentially. In the following description, the third number is assumed to be “3”, but the third number may be a number other than “3”.

  First, voltage 0 (V) is applied to data electrodes D1 to Dm, voltage Ve is applied to sustain electrodes SU1 to SUn, and voltage Vax is applied to scan electrodes SC1 to SCn.

  Next, with the x coordinate detection voltage Vax being applied to the scan electrodes SC1 to SCn, the x coordinate detection pulse of the voltage Vdx is applied to the data electrodes D1 to D3 in the first column to the third column. Then, discharge for detecting the x coordinate (x coordinate detection discharge) is generated in the discharge cells in the first column to the third column. Thus, the first pixel column emits light.

  Next, the x coordinate detection pulse is applied to the data electrodes D4 to D6 in the fourth column to the sixth column while the x coordinate detection voltage Vax is applied to the scan electrodes SC1 to SCn. Then, discharge for detecting the x coordinate occurs in the discharge cells in the fourth to sixth columns. Thus, the second pixel column emits light.

  Similarly, with the x coordinate detection voltage Vax being applied to the scan electrodes SC1 to SCn, the x coordinate detection pulse is sequentially applied to the data electrodes of each of the three columns, and the discharge cell columns are discharged in three columns to discharge the mth column. Light is emitted sequentially until reaching the cell row.

  In this way, in the x coordinate detection period Px1 of the proximity x coordinate detection subfield SFx1, the x coordinate detection pulse is simultaneously applied to the third number of data electrodes while the x coordinate detection voltage Vax is applied to the scan electrodes SC1 to SCn. Perform operations sequentially. In the present embodiment, since the third number is “3”, the operation of sequentially applying the x-coordinate detection pulses to the three data electrodes is sequentially performed. Here, if the third number is “1”, the phrase “sequentially applying the x-coordinate detection pulse to the third number of data electrodes at the same time” means “one data electrode It goes without saying that the operation of applying the x-coordinate detection pulse is sequentially performed.

  Note that the x-coordinate detection discharge generated at this time is the same discharge as the address discharge, which is slightly weaker than the sustain discharge, and the luminance of the light emission accompanying the discharge is slightly lower.

  Thus, in the x-coordinate detection period Px1, the vertical line that emits light with the thickness of one pixel column moves from the left end portion to the right end portion of the image display surface by one pixel column. Therefore, as will be described later, the x-coordinate of the image display surface pointed to by the electronic pen can be detected by receiving the light emission of the vertical line with the electronic pen located near the image display surface and knowing the timing of the light emission.

  The operation of the erasing period Pe of the proximity x coordinate detection subfield SFx1 is the same as the operation of the erasing period Pe of the proximity y coordinate detection subfield SFy1.

  The operation during the initialization period Pi of the remote y coordinate detection subfield SFy2 is the same as the operation during the initialization period Pi of the proximity y coordinate detection subfield SFy1.

  In the y coordinate detection period Py2 of the remote y coordinate detection subfield SFy2, the y coordinate is simultaneously applied to the second number of scan electrodes larger than the first number while the y coordinate detection voltage Vdy is applied to the data electrodes D1 to Dm. The operation of applying the detection pulse is sequentially performed. In the following description, the second number is assumed to be “8”, but the second number may be other than “8”.

  First, voltage 0 (V) is applied to data electrodes D1 to Dm, voltage Ve is applied to sustain electrodes SU1 to SUn, and voltage Vc is applied to scan electrodes SC1 to SCn.

  Next, the y coordinate detection voltage Vdy is applied to the data electrodes D1 to Dm. Then, the y coordinate detection pulse of voltage Vay is applied to a plurality of rows larger than the proximity y coordinate detection subfield SFy1, in this embodiment, the scan electrodes SC1 to SC8 in the first row to the eighth row. Then, discharge for detecting the y coordinate occurs in the discharge cells in the first to eighth rows. Thus, the first to eighth pixel rows emit light.

  Next, with the y coordinate detection voltage Vdy applied to the data electrodes D1 to Dm, the y coordinate detection pulse is applied to the scan electrodes SC2 to SC16 in the next plurality of rows, in the present embodiment, the ninth to sixteenth rows. Apply. Then, discharge for detecting the y coordinate occurs in the discharge cells in the 9th to 16th rows. Thus, the 9th to 16th pixel rows emit light.

  Similarly, in this embodiment, the y coordinate is applied to the scan electrodes SC17 to SCn by a plurality of rows larger than the proximity y coordinate detection subfield SFy1 while the y coordinate detection voltage Vdy is applied to the data electrodes D1 to Dm. The detection pulses are sequentially applied every 8 rows, and the 17th to nth pixel rows are sequentially emitted light by 8 rows.

  Thus, in the y-coordinate detection period Py2 of the remote y-coordinate detection subfield SFy2, the second number larger than the first number while applying the y-coordinate detection voltage Vdy to the data electrodes D1 to Dm, this embodiment In FIG. 5, the operation of applying y-coordinate detection pulses simultaneously to the eight scanning electrodes is sequentially performed.

  As described above, in the remote y-coordinate detection subfield SFy2, the y-coordinate detection discharge is simultaneously emitted in a plurality of rows, that is, 8 pixel rows in the present embodiment, more than in the proximity y-coordinate detection subfield SFy1. Therefore, the luminance of the light emission associated with the discharge is stronger than the light emission associated with the y coordinate detection discharge in the proximity y coordinate detection subfield SFy1.

  Thus, in the remote y-coordinate detection period Py2, the horizontal line that emits light with a thickness of 8 pixel rows moves from the upper end portion to the lower end portion of the image display surface by 8 pixel rows. Therefore, as will be described later, even when the position is far from the image display surface, the electronic pen can receive the emission of the horizontal line, and the y coordinate of the image display surface pointed to by the electronic pen can be detected. However, since the horizontal line moves by 8 pixel rows, the y-coordinate detection accuracy decreases to 1/8.

  The operation of the erasing period Pe of the remote y coordinate detection subfield SFy2 is the same as the operation of the erasing period Pe of the proximity y coordinate detection subfield SFy1.

  The operation in the initialization period Pi of the remote x-coordinate detection subfield SFx2 is the same as the operation in the initialization period Pi of the proximity x-coordinate detection subfield SFx1.

  In the x-coordinate detection period Px2 of the remote x-coordinate detection subfield SFx2, the x-coordinate is simultaneously applied to the fourth number of data electrodes larger than the third number while the x-coordinate detection voltage Vax is applied to the scan electrodes SC1 to SCn. The operation of applying the detection pulse is sequentially performed. In the following description, it is assumed that the fourth number is “24”, but the fourth number may be a number other than “24”.

  First, voltage 0 (V) is applied to data electrodes D1 to Dm, voltage Ve is applied to sustain electrodes SU1 to SUn, and voltage Vax is applied to scan electrodes SC1 to SCn.

  Next, with the x-coordinate detection voltage Vax being applied to the scan electrodes SC1 to SCn, a plurality of columns larger than the proximity x-coordinate detection subfield SFx1, in the present embodiment, the first to 24th column data electrodes An x coordinate detection pulse of voltage Vdx is applied to D1 to D24. Then, discharge for detecting the x coordinate occurs in the discharge cells in the first to 24th columns. Thus, the first to eighth pixel columns emit light.

  Next, with the x-coordinate detection voltage Vax being applied to the scan electrodes SC1 to SCn, the x-coordinate detection pulses are applied to the data electrodes D25 to D48 in the next plurality of columns, in this embodiment, the 25th to 48th columns. Apply. Then, discharge for detecting the x coordinate occurs in the discharge cells in the 25th to 48th columns. Thus, the 9th to 16th pixel columns emit light.

  Similarly, in the present embodiment, a plurality of columns more than the proximity x-coordinate detection subfield SFx1, with the x-coordinate detection voltage Vax being applied to the scan electrodes SC1 to SCn. Coordinate detection pulses are sequentially applied to sequentially emit light by 24 discharge cell rows, that is, 8 pixel rows, up to the mth discharge cell row.

  Thus, in the x-coordinate detection period Px2 of the remote x-coordinate detection subfield SFx2, the fourth number larger than the third number, with the x-coordinate detection voltage Vax being applied to the scan electrodes SC1 to SCn, the present embodiment In FIG. 4, the operation of simultaneously applying x-coordinate detection pulses to 24 data electrodes is sequentially performed.

  As described above, in the remote x-coordinate detection subfield SFx2, multiple x-coordinate detection subfields SFx1 more than the proximity x-coordinate detection subfield SFx1, and in this embodiment, the x-coordinate detection discharge is simultaneously emitted for every eight pixel columns. Therefore, the luminance of the light emission associated with the discharge is stronger than the light emission associated with the x coordinate detection discharge in the proximity x coordinate detection subfield SFx1.

  In this way, in the remote x-coordinate detection period Px2, the vertical line emitting light with the thickness of 8 pixel columns moves by 8 pixel columns from the left end to the right end of the image display surface. Therefore, as will be described later, even when the position is far from the image display surface, the electronic pen can receive the emission of vertical lines, and the x coordinate of the image display surface indicated by the electronic pen can be detected. However, since the vertical line moves by 8 pixel columns, the detection accuracy of the x coordinate is lowered to 1/8.

  The operation of the erasing period Pe of the remote x-coordinate detection subfield SFx2 is the same as the operation of the erasing period Pe of the proximity x-coordinate detection subfield SFx1.

  As described above, in the present embodiment, the coordinate detection subfield includes the synchronization detection subfield SFo, the two y coordinate detection subfields SFy1 and SFy2, and the two x coordinate detection subfields SFx1 and SFx2. Yes.

  In the proximity y-coordinate detection period Py1, the horizontal line that emits light with the thickness of the first number of pixel rows moves from the upper end portion to the lower end portion of the image display surface by the first number of pixel rows to detect the proximity x-coordinate detection. In the period Px1, the vertical lines that emit light with the thickness of the (third number / 3) pixel column move from the left end portion to the right end portion of the image display surface by the (third number / 3) pixel row. For this reason, although the luminance of light emitted from these discharges is low, the coordinates can be detected with high accuracy. As will be described later, in order to detect the coordinates with an electronic pen that is in contact with or close to the image display surface. Used.

  In the remote y-coordinate detection period Py2, the horizontal line that emits light with the thickness of the second number of pixel rows moves from the upper end portion to the lower end portion of the image display surface by the second number of pixel rows. In the detection period Px2, the vertical line that emits light with the thickness of the (fourth number / 3) pixel column moves from the left end portion to the right end portion of the image display surface by the (fourth number / 3) pixel row. Therefore, although the accuracy of coordinates to be detected is deteriorated, the luminance of light emission accompanying these discharges is higher than that in the remote y-coordinate detection period Py1, so that an electronic pen located at a position away from the image display surface as will be described later. Even so, the coordinates can be detected.

  In the above description, the first number is “1”, the second number is “8”, the third number is “3”, and the fourth number is “24”. It is not limited to. For example, the second number is “40”, the fourth number is “120”, and horizontal lines that emit light with a thickness of 40 pixel rows in the remote y coordinate detection period Py2 are from the upper end to the lower end of the image display surface. Forty-eight pixel rows may be moved, and in the remote x-coordinate detection period Px2, vertical lines that emit light with a thickness of 40 pixel columns may be moved by 40 pixel columns from the left end to the right end of the image display surface. By doing so, the accuracy of the coordinates to be detected is deteriorated, but since the luminance of light emission accompanying these discharges is further increased, the distance of the coordinate detection of the electronic pen is increased to, for example, about 8 m, and remote control can be performed even in a large conference room. Can be done.

  In this embodiment, the voltage value applied to each electrode is, for example, voltage Vi1 = 150 (V), voltage Vi2 = 350 (V), voltage Vi4 = −175 (V), voltage Va = voltage Vay = voltage Vax. = −200 (V), voltage Vc = −50 (V), voltage Vs = voltage Vso = 205 (V), voltage Vr = 205 (V), voltage Ve = 155 (V), voltage Vd = voltage Vdy = voltage Vdx = 55 (V). However, these voltage values are merely examples, and it is desirable to set them to optimum values as appropriate in accordance with the characteristics of the panel 10 and the specifications of the image display apparatus.

  Next, the configuration of the image display system will be described.

  FIG. 5 is a circuit block diagram of image display system 100 in the embodiment of the present invention. The image display system 100 is based on the image display device 30, the electronic pen 50 that calculates coordinates on the display screen of the image display device 30 that receives and indicates the light emission of the image display device 30, and the coordinates calculated by the electronic pen 50. And a drawing device 40 that generates a drawing signal and outputs the drawing signal to the image display device 30. A plurality of electronic pens 50 may be provided.

  The image display device 30 includes a panel 10 and a drive circuit. The drive circuit drives the panel 10 by configuring one field period with a plurality of subfields including an image display subfield for displaying an image and a coordinate detection subfield for detecting coordinates. The drive circuit includes an image signal processing unit 31, a data electrode drive unit 32, a scan electrode drive unit 33, a sustain electrode drive unit 34, a control unit 35, and a power supply unit that supplies power necessary for each circuit block ( (Not shown).

  The image signal processing unit 31 switches or synthesizes the input image signal and the image signal output from the drawing device 40, and converts them into image data indicating light emission / non-light emission for each subfield. In addition, horizontal and vertical synchronization signals are output to the control unit 35. The control unit 35 generates various control signals for controlling the operation of each circuit block based on the synchronization signal, and supplies the control signal to each circuit block.

  As shown in FIG. 3, in the image display subfield, the data electrode driving unit 32 converts the image data into address pulses corresponding to the data electrodes D1 to Dm, and applies them to the data electrodes D1 to Dm. . In the coordinate detection subfield, the drive voltage waveform shown in FIG. 4 is applied to each of the data electrodes D1 to Dm.

  Scan electrode driver 33 applies the drive voltage waveforms shown in FIGS. 3 and 4 to each of scan electrodes SC1 to SCn based on the control signal. Sustain electrode drive unit 34 applies the drive voltage waveforms shown in FIGS. 3 and 4 to each of sustain electrodes SU1 to SUn based on the control signal.

  The electronic pen 50 is for inputting characters and pictures from the image display surface of the image display device 30, and includes a light receiving element 52, a synchronization detection unit 54, a coordinate calculation unit 56, and a transmission unit 58. Have.

  The light receiving element 52 receives light emitted from the image display device 30 and outputs a light reception signal to the synchronization detection unit 54 and the coordinate calculation unit 56. In order to efficiently collect the emitted light, a configuration in which lenses are combined may be used.

  The synchronization detection unit 54 detects light emission generated at a time interval corresponding to a predetermined number sequence determined in advance from the received light signal, and identifies the synchronization detection discharge in the synchronization detection period Po of the synchronization detection subfield SFo. A coordinate reference signal synchronized with the y-coordinate detection subfields SFy1 and SFy2 and the x-coordinate detection subfields SFx1 and SFx2 is generated based on the received light signal.

  In the present embodiment, the synchronization detection unit 54 searches the received light signal for four consecutive lights whose light emission intervals are time To1, time To2, and time To3. When four consecutive luminescences are detected, the start time ty01 and the x coordinate of the y-coordinate detection period Py1 are determined based on one of the luminescences, for example, the luminescence generated at the time to1, based on a predetermined time. A coordinate reference signal having rises at the start time tx01 of the detection period Px1, the start time ty02 of the y coordinate detection period Py2, and the start time tx02 of the x coordinate detection period Px2 is generated and output to the coordinate calculation unit 56.

  The coordinate calculation unit 56 includes a counter for measuring the length of time, and an arithmetic circuit that performs an operation on the output of the counter. Then, the x coordinate and the y coordinate on the display screen of the image display device 30 indicated by the electronic pen 50 are calculated based on the coordinate reference signal output from the control unit 35 and the light reception signal output from the light receiving element 52.

  First, a case where the electronic pen 50 is used while being in contact with the image display surface of the image display device 30 or a case where the electronic pen 50 is used at a position close to the image display surface will be described.

  FIG. 6 is a schematic diagram for explaining the position coordinate detection method of the image display system 100 according to the embodiment of the present invention. In the case where the electronic pen 50 is used while being in contact with the image display surface of the image display device 30, the image display is performed. The case where it uses in the position close | similar to a surface is shown. FIG. 7 is an example of a timing chart for explaining the position coordinate detection method of the image display system 100 according to the embodiment of the present invention. The drive voltage waveforms of the scan electrodes SC1 to SCn and the drive voltage waveforms of the data electrodes D1 to Dm. The light receiving signal in this case is shown together with the coordinate reference signal. Here, the threshold value th indicates the lowest level of the received light signal that allows the light receiving element 52 to detect light emission stably.

  As described above, in the y coordinate detection period Py1 of the proximity y coordinate detection subfield SFy1, the horizontal line Ly1 moving from the upper end portion to the lower end portion of the image display surface is displayed. Then, at time tyy1 when the horizontal line Ly1 passes through the coordinates (x, y) of the image display surface pointed to by the electronic pen 50, the light receiving element 52 receives light emission of the horizontal line Ly1. Therefore, the light receiving element 52 outputs a light reception signal indicating light reception at time tyy1. Further, in the x coordinate detection period Px1 of the proximity x coordinate detection subfield SFx1, a vertical line Lx1 moving from the left end portion to the right end portion of the image display surface is displayed. Then, at time txx1 when the vertical line Lx1 passes through the coordinates (x, y) of the image display surface pointed to by the electronic pen 50, the light receiving element 52 receives light emission of the vertical line Lx1. Therefore, the light receiving element 52 outputs a light reception signal indicating light reception at time txx1.

  Here, the time from time ty01 to time ty1 is time Ty1, the time from time ty01 to applying the y coordinate detection pulse to the first scan electrode SC1 is time Ty01, and the cycle of applying the y coordinate detection pulse is time Ty11. Then, the coordinate calculation part 56 calculates | requires y coordinate by dividing time (Tyy1-Ty01) by time Ty11. Further, assuming that the time from time tx01 to time txx1 is time Txx1, the time until the first application of the x coordinate detection pulse is time Tx01, and the cycle of applying the x coordinate detection pulse is time Tx11, the coordinate calculation unit 56 Divide (Txx1-Tx01) by time Tx11 to obtain the x coordinate.

  When the light receiving element 52 receives the light emission of the horizontal line Ly1 of the proximity y coordinate detection subfield SFy1, it also receives the light emission of the horizontal line Ly2 of the remote y coordinate detection subfield SFy2, and the proximity x coordinate detection subfield SFx1. When the light emission of the vertical line Lx1 is received, the light emission of the vertical line Lx2 of the remote x-coordinate detection subfield SFx2 is also received. However, when the light emission of the horizontal line Ly1 is received, the coordinate calculation unit 56 detects the y coordinate using the light emission of the horizontal line Ly1. When the light emission of the vertical line Lx1 is received, the x coordinate is detected using the light emission of the vertical line Lx1.

  Next, the case where the electronic pen 50 is used far away from the image display surface of the image display device 30 will be described.

  FIG. 8 is a schematic diagram for explaining the position coordinate detection method of the image display system 100 according to the embodiment of the present invention, and shows a case where the electronic pen 50 is used separately from the image display surface of the image display device 30. . FIG. 9 is another example of a timing chart illustrating the position coordinate detection method of the image display system 100 according to the embodiment of the present invention. The drive voltage waveforms of the scan electrodes SC1 to SCn and the drive of the data electrodes D1 to Dm. The light reception signal in this case is shown together with the voltage waveform and the coordinate reference signal. Here again, the threshold th indicates the lowest level of the received light signal that allows the light receiving element 52 to detect light emission stably.

  As described above, the horizontal line Ly1 displayed in the y coordinate detection period Py1 of the proximity y coordinate detection subfield SFy1 and the vertical line Lx1 displayed in the x coordinate detection period Px1 of the proximity x coordinate detection subfield SFx1 have luminance. Therefore, if the electronic pen 50 is away from the image display surface, the emitted light may not be received depending on the distance.

  However, if the light emission of the horizontal line Ly2 can be received at the time tyy2 when the horizontal line Ly2 passes through the coordinates (x, y) of the image display surface pointed to by the electronic pen 50, the light receiving element 52 receives a light reception signal indicating the reception of the time tyy2. Output. If the light emission of the vertical line Lx2 can be received at the time txx2 when the vertical line Lx2 passes the coordinates (x, y) of the image display surface pointed to by the electronic pen 50, the light receiving element 52 receives the light reception signal indicating the reception of the time txx2. Is output.

  As described above, even when the light receiving element 52 cannot receive the light emission of the horizontal line Ly1 and the vertical line Lx1 emitted in the proximity coordinate detection subfields SFy1 and SFx1, the remote coordinate detection subfields SFy2 and SFx2 If the light emission of the horizontal line Ly2 and the vertical line Lx2 to be emitted can be received, the coordinate calculation unit 56 calculates the coordinates (x, y) on the display screen of the image display device 30 indicated by the electronic pen 50.

  Here, assuming that the time from time ty02 to time ty2 is time Tyy2, the time from the time ty02 to the first application of the y coordinate detection pulse is time Ty02, and the cycle of applying the y coordinate detection pulse is time Ty12, the coordinate calculation unit In 56, the value obtained by dividing the time (Tyy2−Ty02) by the time Ty12 is multiplied by a plurality of times, and in this embodiment, the y coordinate is obtained. Further, assuming that the time from time tx02 to time txx2 is time Txx2, the time from the time tx02 to the first application of the x coordinate detection pulse is time Tx02, and the cycle of applying the x coordinate detection pulse is time Tx12, the coordinate calculation unit 56 Is obtained by multiplying the value obtained by dividing the time (Txx2-Tx02) by the time Tx12 by a plurality of times, and in the present embodiment, multiplied by 8 to obtain the x coordinate. However, in this case, the position of the horizontal line moves by 8 pixels every time Ty12, and the position of the vertical line moves by 8 pixels every time Tx12, so the resolution becomes 8 pixels.

  In this way, if the light receiving element 52 of the electronic pen 50 can receive the light emission of the horizontal line Ly1 and the vertical line Lx1, the coordinate calculation unit 56 determines the coordinates (x, y) indicated by the electronic pen 50 based on the timing of the light emission. Find accurately. Even if the light receiving element 52 cannot receive the light emission of the horizontal line Ly1 and the vertical line Lx1, if the light emission of the horizontal line Ly2 and the vertical line Lx2 can be received, the accuracy of the electronic pen 50 is inferior based on the timing of the light emission. The coordinates (x, y) of the image display surface pointed to are obtained.

  The transmission unit 58 encodes the x coordinate and the y coordinate calculated by the coordinate calculation unit 56 and transmits them to the reception unit 42 of the drawing apparatus 40 wirelessly.

  The drawing device 40 creates an image signal based on the coordinates (x, y) of the image display surface pointed to by the electronic pen 50. This image signal is for displaying an image drawn by the user. The drawing device 40 includes a receiving unit 42 and a drawing unit 46.

  The receiving unit 42 receives the coordinates (x, y) transmitted from the electronic pen 50 and outputs them to the drawing unit 46.

  The drawing unit 46 includes a frame memory, generates a drawing signal indicating the locus of the electronic pen 50 on the image display surface based on the coordinates (x, y) received by the receiving unit 42, and outputs the drawing signal to the image display device 30. .

  FIG. 10 is a schematic diagram showing an example of drawing of the image display system 100 in the embodiment of the present invention. The drawing unit 46 writes a pattern such as a circle of a predetermined color and size in the frame memory around the pixel corresponding to the coordinates (x, y) calculated by the coordinate calculation unit 56. When the user moves the position indicated by the electronic pen 50, the coordinates (x, y) calculated by the coordinate calculation unit 56 also move. The drawing unit 46 writes the cursor pattern centered on the coordinates (x, y) in the current field to the frame memory while erasing the cursor pattern centered on the coordinates (x, y) in the previous field. Then, a drawing signal for displaying the cursor at the position indicated by the electronic pen 50 is created. The drawing unit 46 sequentially overwrites the frame memory with the predetermined pattern centered on the moving coordinate (x, y) without deleting the predetermined pattern centered on the coordinate (x, y) in the previous field. Thus, as shown in FIG. 10, a drawing signal indicating the locus of the electronic pen 50 on the image display surface is created.

  Then, the image signal processing unit 31 of the image display device 30 synthesizes the input image signal and the drawing signal output from the drawing unit 46 and converts them into image data indicating light emission / non-light emission for each subfield. Thereby, the image written with the electronic pen 50 and the image of the input image signal are superimposed and displayed.

  As described above, the image display device 30 in the present embodiment applies the y-coordinate detection voltage Vdy to the image display subfields SF1 to SF8 for displaying an image and the data electrodes D1 to Dm for one field period. From the first number, the y-coordinate detection subfield SFy1 for proximity that sequentially applies the y-coordinate detection pulse to the first number of scan electrodes and the y-coordinate detection voltage Vdy applied to the data electrodes D1 to Dm. Remote y-coordinate detection subfield SFy2 that sequentially applies the y-coordinate detection pulse to the second number of scan electrodes at the same time, and the third with the x-coordinate detection voltage Vax applied to the scan electrodes SC1 to SCn. Proximity x-coordinate detection subfield SFx1 that sequentially applies an x-coordinate detection pulse to several data electrodes, and scan electrodes SC1 to SC. A remote x-coordinate detection subfield SFx2 for sequentially performing an operation of simultaneously applying x-coordinate detection pulses to a fourth number of data electrodes larger than the third number while applying the x-coordinate detection voltage Vax to It consists of subfields. When the electronic pen 50 receives the light emission of the proximity y coordinate detection subfield SFy1, the electronic pen 50 calculates the y coordinate using the light emission of the proximity y coordinate detection subfield SFy1, and emits the light of the proximity y coordinate detection subfield SFy1. If the light emission of the remote y coordinate detection subfield SFy2 is received without receiving the light, the y coordinate is calculated using the light emission of the remote y coordinate detection subfield SFy2, and the light emission of the proximity x coordinate detection subfield SFx1 is received. In this case, the x coordinate is calculated using the light emission of the proximity x coordinate detection subfield SFx1, and the light emission of the remote x coordinate detection subfield SFx2 is received without receiving the light emission of the proximity x coordinate detection subfield SFx1. Calculates the x-coordinate using the light emitted from the remote x-coordinate detection subfield SFx2.

  In each of the coordinate detection subfields, since a discharge different from that of the normal image display subfield is generated, the initialization of the wall voltage becomes unstable, and the probability of erroneous operation such as erroneous lighting or non-lighting increases. . Next, an example of an initialization operation for suppressing such a malfunction and performing stable driving will be described.

  FIG. 11 is another drive voltage waveform diagram applied to panel 10 of the image display system in the embodiment of the present invention, and shows the drive voltage waveform applied to each electrode of panel 10 in each of the coordinate detection subfields. Yes. Hereinafter, only the initialization period of each coordinate detection subfield will be described in detail.

  In the initialization period Pi of the synchronization detection subfield SFo, the voltage Vd is applied to the data electrodes D1 to Dm, the voltage 0 (V) is applied to the sustain electrodes SU1 to SUn, and the voltages Vi1 to Vi2 are applied to the scan electrodes SC1 to SCn. Apply an ascending ramp voltage that rises to Next, voltage 0 (V) is applied to data electrodes D1 to Dm, voltage Ve1 lower than voltage Ve is applied to sustain electrodes SU1 to SUn, and scan electrodes SC1 to SCn are decreased from voltage 0 (V) to voltage Vi4. Apply a downward ramp voltage.

  Then, a weak initializing discharge occurs in all the discharge cells, the wall voltage on scan electrodes SC1 to SCn and the wall voltage on sustain electrodes SU1 to SUn are weakened, and the wall voltage on data electrodes D1 to Dm is written. It is adjusted to a value suitable for operation.

  In the initialization period Pi of the proximity y coordinate detection subfield SFy1, the voltage 0 (V) is applied to the data electrodes D1 to Dm, the voltage 0 (V) is applied to the sustain electrodes SU1 to SUn, and the scan electrodes SC1 to SCn. A downward ramp voltage that drops from voltage 0 (V) to voltage Vi4 is applied. Next, voltage 0 (V) is applied to data electrodes D1 to Dm, voltage 0 (V) is applied to sustain electrodes SU1 to SUn, and voltage Vs is applied to scan electrodes SC1 to SCn. Next, voltage Vs is applied to sustain electrodes SU1 to SUn, and voltage 0 (V) is applied to scan electrodes SC1 to SCn. Next, voltage Ve1 is applied to sustain electrodes SU1 to SUn, and a downward ramp voltage that drops from voltage 0 (V) to voltage Vi4 is applied to scan electrodes SC1 to SCn.

  Then, a weak initializing discharge occurs in all the discharge cells, the wall voltage on scan electrodes SC1 to SCn and the wall voltage on sustain electrodes SU1 to SUn are weakened, and the wall voltage on data electrodes D1 to Dm becomes y It is adjusted to a value suitable for discharge for coordinate detection.

  In the initialization period Pi of the proximity x-coordinate detection subfield SFx1, the voltage Vd is applied to the data electrodes D1 to Dm, the voltage 0 (V) is applied to the sustain electrodes SU1 to SUn, and the voltage Vi1 is applied to the scan electrodes SC1 to SCn. To the voltage Vi2 is applied. Next, the voltage 0 (V) is applied to the data electrodes D1 to Dm, the voltage Ve1 is applied to the sustain electrodes SU1 to SUn, and the downward ramp voltage that drops from the voltage 0 (V) to the voltage Va is applied to the scan electrodes SC1 to SCn. Apply. Further, an ascending ramp voltage that rises from voltage 0 (V) to voltage Vr is applied to scan electrodes SC1 to SCn, and then a descending ramp voltage that descends from voltage 0 (V) to x-coordinate detection voltage Vax is applied to scan electrodes SC1 to SCn. Apply.

  Then, a weak initializing discharge occurs in all the discharge cells, the wall voltage on scan electrodes SC1 to SCn and the wall voltage on sustain electrodes SU1 to SUn are weakened, and the wall voltage on data electrodes D1 to Dm becomes x It is adjusted to a value suitable for discharge for coordinate detection.

  In the initialization period Pi of the remote y-coordinate detection subfield SFy2, the voltage Vd is applied to the data electrodes D1 to Dm, the voltage 0 (V) is applied to the sustain electrodes SU1 to SUn, and the voltage Vi1 is applied to the scan electrodes SC1 to SCn. To the voltage Vi2 is applied. Next, the voltage 0 (V) is applied to the data electrodes D1 to Dm, the voltage Ve1 is applied to the sustain electrodes SU1 to SUn, and a downward ramp voltage that drops from the voltage 0 (V) to the voltage Vi4 is applied to the scan electrodes SC1 to SCn. Apply.

  Then, a weak initializing discharge occurs in all the discharge cells, the wall voltage on scan electrodes SC1 to SCn and the wall voltage on sustain electrodes SU1 to SUn are weakened, and the wall voltage on data electrodes D1 to Dm becomes y It is adjusted to a value suitable for discharge for coordinate detection.

  In the initialization period Pi of the remote x-coordinate detection subfield SFx2, the voltage Vd is applied to the data electrodes D1 to Dm, the voltage 0 (V) is applied to the sustain electrodes SU1 to SUn, and the voltage Vi1 is applied to the scan electrodes SC1 to SCn. To the voltage Vi2 is applied. Next, the voltage 0 (V) is applied to the data electrodes D1 to Dm, the voltage Ve1 is applied to the sustain electrodes SU1 to SUn, and the downward ramp voltage that drops from the voltage 0 (V) to the voltage Va is applied to the scan electrodes SC1 to SCn. Apply. Further, an ascending ramp voltage that rises from voltage 0 (V) to voltage Vr is applied to scan electrodes SC1 to SCn, and then a descending ramp voltage that descends from voltage 0 (V) to x-coordinate detection voltage Vax is applied to scan electrodes SC1 to SCn. Apply.

  Then, a weak initializing discharge occurs in all the discharge cells, the wall voltage on scan electrodes SC1 to SCn and the wall voltage on sustain electrodes SU1 to SUn are weakened, and the wall voltage on data electrodes D1 to Dm becomes x It is adjusted to a value suitable for discharge for coordinate detection.

  In the erasing period Pe of the remote x-coordinate detection subfield SFx2, the voltage 0 (V) is applied to the data electrodes D1 to Dm, the voltage 0 (V) is applied to the sustain electrodes SU1 to SUn, and the scan electrodes SC1 to SCn are applied. After applying the rising ramp voltage rising from the voltage 0 (V) to the voltage Vr, as shown in FIG. 11, the rising ramp voltage rising from the voltage Vi1 to the voltage Vi2 may be applied.

  In the embodiment, a horizontal line is shown in which, in the y coordinate detection period Py1, the discharge cell rows are sequentially light-emitted one by one and moved from the upper end portion to the lower end portion of the image display surface. However, the present invention is not limited to this. For example, a horizontal line that moves by sequentially emitting light by two discharge cell rows may be displayed, or a horizontal line that moves by discharging every other discharge cell row may be displayed. Similarly, in the x-coordinate detection period Px1, the discharge cell rows may be caused to emit light sequentially in an arbitrary plurality of rows, or the discharge cell rows may be caused to emit light every other row. The same applies to the y-coordinate detection period Py2 and the x-coordinate detection period Px2. As a result, the luminance can be further reduced, and the time required for the y-coordinate detection subfields SFy1 and SFy2 and the x-coordinate detection subfields SFx1 and SFx2 can be shortened.

  Further, the specific numerical values used in the embodiments are merely examples, and it is desirable to appropriately set the values appropriately according to the characteristics of the panel, the specifications of the plasma display device, and the like.

  Since the present invention generates light emission capable of detecting coordinates from a position close to the image display surface and a position distant from the image display surface, drawing using the image display device driving method, the image display device, and the electronic pen It is useful as a possible image display system.

DESCRIPTION OF SYMBOLS 10 Panel 12 Scan electrode 13 Sustain electrode 22 Data electrode 30 Image display apparatus 40 Drawing apparatus 42 Receiving part 46 Drawing part 50 Electronic pen 52 Light receiving element 54 Synchronization detection part 56 Coordinate calculation part 58 Transmission part 100 Image display system

Claims (5)

Driving an image display device using an image display element having a plurality of scan electrodes and sustain electrodes extending in a first direction and a plurality of data electrodes extending in a second direction intersecting the first direction A method,
An image display subfield for displaying an image for one field period, and proximity in which a y-coordinate detection pulse is simultaneously applied to the first number of scan electrodes while a y-coordinate detection voltage is applied to the data electrodes A remote y-coordinate detection sub-field and an operation for sequentially applying y-coordinate detection pulses to a second number of scan electrodes greater than the first number while applying a y-coordinate detection voltage to the data electrodes. a y-coordinate detection subfield, a proximity x-coordinate detection subfield that sequentially applies an x-coordinate detection pulse to a third number of data electrodes while applying an x-coordinate detection voltage to the scan electrode, and the scan Remote x-coordinate detection for sequentially performing an operation of simultaneously applying x-coordinate detection pulses to a fourth number of data electrodes greater than the third number while applying an x-coordinate detection voltage to the electrodes. The driving method of the image display apparatus characterized by being configured of a plurality of subfields comprising a subfield, the. Driving an image display device using an image display element having a plurality of scan electrodes and sustain electrodes extending in a first direction and a plurality of data electrodes extending in a second direction intersecting the first direction A method,
An operation of applying a y-coordinate detection pulse to the first number “1” scan electrode while applying a y-coordinate detection voltage to the data electrode, and an image display subfield for displaying an image during one field period And a y-coordinate detection subfield for proximity, and a y-coordinate detection pulse simultaneously applied to a second number of scan electrodes greater than the first number “1” while a y-coordinate detection voltage is applied to the data electrode. A remote y-coordinate detection subfield for sequentially applying the X-coordinate operation, and an operation of applying an x-coordinate detection pulse to the data electrode “1” which is the third number while applying the x-coordinate detection voltage to the scan electrode. X-coordinate detection pulses for proximity, which are sequentially performed, and x-coordinate detection pulses are simultaneously applied to a fourth number of data electrodes greater than the third number “1” while an x-coordinate detection voltage is applied to the scan electrodes. The driving method of the image display apparatus characterized by being configured of a plurality of subfields including a x-coordinate detection subfield for remotely operates to pressure sequentially to. An image display element having a plurality of scan electrodes and sustain electrodes extending in a first direction and a plurality of data electrodes extending in a second direction intersecting the first direction, and a field period having a plurality of subfields An image display device comprising a drive circuit configured to drive the image display element,
The drive circuit is
An image display subfield for displaying an image for one field period, and proximity in which a y-coordinate detection pulse is simultaneously applied to the first number of scan electrodes while a y-coordinate detection voltage is applied to the data electrodes A remote y-coordinate detection sub-field and an operation for sequentially applying y-coordinate detection pulses to a second number of scan electrodes greater than the first number while applying a y-coordinate detection voltage to the data electrodes. a y-coordinate detection subfield, a proximity x-coordinate detection subfield that sequentially applies an x-coordinate detection pulse to a third number of data electrodes while applying an x-coordinate detection voltage to the scan electrode, and the scan Remote x-coordinate detection for sequentially performing an operation of simultaneously applying x-coordinate detection pulses to a fourth number of data electrodes greater than the third number while applying an x-coordinate detection voltage to the electrodes. Subfield, composed of a plurality of sub-fields including an image display apparatus characterized by driving the image display device. An image display element having a plurality of scan electrodes and sustain electrodes extending in a first direction and a plurality of data electrodes extending in a second direction intersecting the first direction, and a field period having a plurality of subfields An image display device comprising a drive circuit configured to drive the image display element,
The drive circuit is
An operation of applying a y-coordinate detection pulse to the first number “1” scan electrode while applying a y-coordinate detection voltage to the data electrode, and an image display subfield for displaying an image during one field period And a y-coordinate detection subfield for proximity, and a y-coordinate detection pulse simultaneously applied to a second number of scan electrodes greater than the first number “1” while a y-coordinate detection voltage is applied to the data electrode. A remote y-coordinate detection subfield for sequentially applying the X-coordinate operation, and an operation of applying an x-coordinate detection pulse to the data electrode “1” which is the third number while applying the x-coordinate detection voltage to the scan electrode. X-coordinate detection pulses for proximity, which are sequentially performed, and x-coordinate detection pulses are simultaneously applied to a fourth number of data electrodes greater than the third number “1” while an x-coordinate detection voltage is applied to the scan electrodes. And x-coordinate detection subfield for remotely operates to pressurization sequence, composed of a plurality of sub-fields including an image display apparatus characterized by driving the image display device. 5. The image display device according to claim 3, an electronic pen that calculates coordinates on a display screen of the image display device that receives and indicates light emission of the image display device, and the coordinates calculated by the electronic pen A drawing circuit that creates a drawing signal and outputs the drawing signal to the image display device;
When the electronic pen receives the light emission of the proximity y coordinate detection subfield, the electronic pen calculates the y coordinate using the light emission of the proximity y coordinate detection subfield, and emits the light of the proximity y coordinate detection subfield. When the light emitted from the remote y coordinate detection subfield is received without receiving light, the y coordinate is calculated using the light emitted from the remote y coordinate detection subfield, and the light emitted from the proximity x coordinate detection subfield is received. In this case, the x coordinate is calculated using the light emission of the proximity x coordinate detection subfield, and the light emission of the remote x coordinate detection subfield is received without receiving the light emission of the proximity x coordinate detection subfield. An x-coordinate is calculated by using light emission of the remote x-coordinate detection subfield.

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