JP2012194341A - Control method of electro-optical device, controller of electro-optical device, electro-optical device and electronic apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To surely display a line image that has a narrow line width in an electro-optical device such as an electrophoretic display device.SOLUTION: A control method of an electro-optical device includes: a first a display control step in which first gradation is displayed by a second pixel by controlling a driving section such that one potential of a high potential (VH) and a low potential (VL) is supplied to pixel electrodes (21Bw and 21Bb) in the second pixel positioned adjacent to a first pixel corresponding to a line image out of a plurality of pixels in a case where the line image that has a line width narrower than a predetermined width is included in an image to be displayed; and a second display control step in which second gradation different from the first gradation is displayed by the first pixel subsequent to the first display control step by controlling the driving section such that other potential of the high potential (VH) and the low potential (VL) is supplied to pixel electrodes in the first pixel while reference potential is supplied to pixel electrodes (21Lb and 21Lw) in the second pixel.

Description

  The present invention relates to a control method for an electro-optical device such as an electrophoretic display device, a control device for the electro-optical device, an electro-optical device, and an electronic device.

  As an example of this type of electro-optical device, an electrophoretic particle is moved by applying a voltage between a pixel electrode and a counter electrode provided to sandwich an electrophoretic element having a dispersion medium containing the electrophoretic particle. Thus, there is an electrophoretic display device that displays an image (see, for example, Patent Document 1). The electrophoretic element includes, for example, black particles and white particles as the electrophoretic particles, and these two kinds of particles are selectively attracted to the counter electrode side for each pixel, so that two gradations of black or white are obtained. Is displayed.

  In such an electrophoretic display device, for example, a positive electrode potential (for example, 15 volts) higher than the potential of the counter electrode (for example, 0 volt) is supplied to the pixel electrode of a pixel to display black, and white is An image is displayed by supplying a negative potential (for example, −15 volts) lower than the potential of the counter electrode to the pixel electrode of the pixel to be displayed (for example, see Patent Document 1).

JP 2006-227470 A

  In the electrophoretic display device described above, when displaying an image, for example, when one pixel that should display black is positioned between two pixels that should display white (that is, a pixel to which a positive potential is supplied) When an electrode is positioned between two pixel electrodes to which a negative potential is supplied, in other words, a negative potential is supplied to a pixel electrode adjacent to a pixel electrode to which a positive potential is supplied. When a strong electric field is generated between the pixel electrode of the pixel that should display black and the pixel electrode of the pixel that should display white, the pixel electrode between the pixel that should display black and the counter electrode However, there is a technical problem that a sufficient voltage cannot be applied to the pixel, and it may be difficult to display black on a pixel that should display black. For this reason, for example, it may be difficult to appropriately display a line image having a thin line width such as a line width corresponding to the width of one pixel (that is, the width of one pixel). That is, the line width of the displayed line image may be narrower than the line width of the line image to be displayed, or the line image to be displayed may be hardly or not displayed at all.

  The present invention has been made in view of the above-described problems, for example, and can reliably display a line image having a thin line width such as a line width corresponding to the width of one pixel, thereby displaying a high-quality image. It is an object of the present invention to provide an electro-optical device control method, an electro-optical device control device, an electro-optical device, and an electronic apparatus.

  In order to solve the above problems, a control method for an electro-optical device according to the present invention includes a display unit including a pixel electrode facing each other and a plurality of pixels each having an electro-optical material between the counter electrodes, and a display on the display unit. A control method for controlling an electro-optical device including a drive unit that applies a voltage between the pixel electrode and the counter electrode according to a power image, wherein the image to be displayed has a line width smaller than a predetermined width. A line image having a high potential higher than a reference potential and the reference in the pixel electrode in the second pixel located adjacent to the first pixel corresponding to the line image among the plurality of pixels. A first display control step of displaying the first gradation on the second pixel by controlling the driving unit so that one of the low potentials lower than the potential is supplied; After the display control process, The reference potential is supplied to the pixel electrode in two pixels, and the other potential different from the one of the high potential and the low potential is supplied to the pixel electrode in the first pixel. And a second display control step of causing the first pixel to display a second gradation different from the first gradation by controlling the driving unit.

  The control method of the electro-optical device according to the present invention includes a display unit including a plurality of pixels each having an electro-optical material such as an electrophoretic particle between pixel electrodes facing each other and the counter electrode, and displays on the display unit. This is a control method for controlling an electro-optical device such as an electrophoretic display device, which includes a drive unit that applies a voltage between a pixel electrode and a counter electrode according to a power image. The electro-optical device can display an image on the display unit by changing the state of an electro-optical material such as electrophoretic particles according to the voltage applied between the pixel electrode and the counter electrode. For example, the driving unit supplies a reference potential to the counter electrode and supplies a high potential higher than the reference potential or a low potential lower than the reference potential to the pixel electrode according to the gradation to be displayed. A voltage is applied between the pixel electrode and the counter electrode.

  According to the control method of the electro-optical device according to the invention, the image to be displayed includes a line image having a line width smaller than a predetermined width (for example, a line image having a line width corresponding to the width of one pixel). If the first display control step and the second display control step are performed in this order, an image to be displayed is displayed on the display unit.

  In the first display control step, one of the low potential and the high potential is supplied to the pixel electrode in the second pixel adjacent to the first pixel corresponding to the line image among the plurality of pixels. By controlling the drive unit, the first gradation (for example, white) is displayed on the second pixel. That is, in the first display control step, the first gradation (for example, white) serving as the background of the line image (for example, the second gradation line image that is black) having a line width smaller than the predetermined width is the line image. One potential (that is, the potential corresponding to the first gradation of the low potential and the high potential) is applied to the pixel electrode in the second pixel so as to be displayed on the second pixel adjacent to the first pixel corresponding to the first pixel. Is supplied by the drive. In the first display control step, a voltage may be applied between the pixel electrode and the counter electrode in the first pixel so that the first gradation is displayed on the first pixel (for example, in the first pixel). A potential corresponding to the second gradation among the low potential and the high potential may be supplied to the pixel electrode, or a voltage may not be applied (for example, a reference potential is supplied to the pixel electrode in the first pixel). May be).

  In the second display control step, the reference potential is supplied to the pixel electrode in the second pixel, and the other potential (that is, the first potential) different from one of the high potential and the low potential is applied to the pixel electrode in the first pixel. By controlling the driving unit so that a potential corresponding to two gradations is supplied, the second gradation (for example, black) is displayed on the first pixel. That is, in the second display control step, the reference potential is supplied to the pixel electrode of the second pixel that is in a state of displaying the first gradation (for example, white) as the background, and the first pixel corresponding to the line image. By supplying the other potential (that is, the potential corresponding to the second gradation) to the pixel electrode in the display portion, the display section has the second gradation (for example, black) with the first gradation (for example, white) as the background. The line image is displayed.

  Here, it is assumed that one potential (for example, low potential) corresponding to the first gradation (for example, white) among the high potential and the low potential is supplied to the pixel electrode in the second pixel serving as the background among the plurality of pixels. In the state where the other potential (for example, high potential) corresponding to the second gradation (for example, black) is supplied to the pixel electrode in the first pixel corresponding to the line image, among the high potential and the low potential, A voltage to be applied is sufficiently applied between the pixel electrode and the counter electrode in the first pixel corresponding to the line image by the electric field generated by the potential difference between the pixel electrode in the second pixel and the pixel electrode in the first pixel. It is difficult to display the line image properly. For example, the line width of the line image displayed on the display unit may be thinner than the line width of the line image to be displayed, or the line image to be displayed may be hardly or not displayed at all.

  In the present invention, however, in the second display control step, the reference potential is supplied to the pixel electrode in the second pixel and the other potential (that is, the potential corresponding to the second gradation) is applied to the pixel electrode in the first pixel. Is supplied. Therefore, for example, in a state where one potential (for example, low potential) is supplied to the pixel electrode in the second pixel serving as the background, the other potential (for example, the pixel electrode in the first pixel corresponding to the line image) The potential difference between the pixel electrode in the second pixel and the pixel electrode in the first pixel can be reduced compared to the case where a high potential is supplied, and the pixel electrode in the first pixel corresponding to the line image A sufficient voltage can be applied between the counter electrode and the counter electrode. Therefore, it is possible to reliably display a line image having a line width smaller than the predetermined width (for example, a line image having a line width corresponding to the width of one pixel). That is, for example, it is possible to avoid a situation in which the line width of the line image displayed on the display unit is narrower than the line width of the line image to be displayed or the line image to be displayed is hardly or not displayed at all. Can do. As a result, a high quality image can be displayed.

  As described above, according to the control method of the electro-optical device according to the present invention, a line image having a thin line width such as a line width corresponding to the width of one pixel is reliably displayed on the display unit of the electro-optical device. Can be made. As a result, a high quality image can be displayed.

  In one aspect of the control method of the electro-optical device according to the invention, the first display control step controls the driving unit so that the other potential is supplied to the pixel electrode in the first pixel.

  According to this aspect, the first and second display control steps can reliably apply a voltage between the pixel electrode and the counter electrode in the first pixel so that the first gradation is displayed on the first pixel. it can. Therefore, the line image can be reliably displayed on the display unit.

  In another aspect of the method for controlling an electro-optical device according to the present invention, the first display control step controls the driving unit so that the reference potential is supplied to the pixel electrode in the first pixel.

  According to this aspect, in the first display control step, the reference potential is supplied to the pixel electrode in the first pixel, so that no voltage is applied between the pixel electrode and the counter electrode in the first pixel. Therefore, in the second display control step, the other potential is supplied to the pixel electrode in the first pixel, and a voltage is applied between the pixel electrode and the counter electrode in the first pixel, so that the pixel electrode in the first pixel is opposed to the pixel electrode. It can be suppressed that a voltage is excessively applied between the electrodes and electro-optical materials such as electrophoretic particles are damaged or deteriorated.

  In order to solve the above problems, a control device for an electro-optical device according to the present invention includes a display unit including a pixel electrode facing each other and a plurality of pixels each having an electro-optical material between the counter electrodes, and displays on the display unit. A control device that controls an electro-optical device including a drive unit that applies a voltage between the pixel electrode and the counter electrode according to an image to be displayed, wherein the image to be displayed has a line width smaller than a predetermined width. A line image having a high potential higher than a reference potential and the reference in the pixel electrode in the second pixel located adjacent to the first pixel corresponding to the line image among the plurality of pixels. First display control means for displaying the first gradation on the second pixel by controlling the driving section so that one of the low potentials lower than the potential is supplied; The display control means After the first gradation is displayed in two pixels, the reference potential is supplied to the pixel electrode in the second pixel, and the high potential and the low potential are applied to the pixel electrode in the first pixel. A second display that causes the first pixel to display a second gradation different from the first gradation by controlling the driving unit so that the other potential different from the one potential is supplied. Control means.

  According to the control apparatus for an electro-optical device according to the present invention, a thin line width such as a line width corresponding to the width of one pixel is reduced in the electro-optical device, similarly to the control method for the electro-optical device according to the present invention described above. Therefore, it is possible to reliably display the line image, and to display a high-quality image.

  The electro-optical device control apparatus according to the present invention can also adopt various aspects similar to the various aspects of the electro-optical device control method according to the present invention described above.

  In order to solve the above problems, an electro-optical device according to the present invention includes the above-described electro-optical device control device according to the present invention (including various aspects thereof).

  According to the electro-optical device according to the present invention, since the electro-optical device control device according to the present invention described above is provided, a line image having a thin line width such as a line width corresponding to the width of one pixel is reliably displayed. Can display high-quality images.

  In order to solve the above problems, an electronic apparatus according to the present invention includes the above-described electro-optical device according to the present invention (including various aspects thereof).

  The electronic apparatus according to the present invention includes the above-described electro-optical device according to the present invention, so that a high-quality image can be displayed, for example, a wristwatch, electronic paper, an electronic notebook, a mobile phone, and a portable device. Various electronic devices such as audio devices can be realized.

  The effect | action and other gain of this invention are clarified from the form for implementing invention demonstrated below.

1 is a block diagram illustrating an overall configuration of an electrophoretic display device according to a first embodiment. FIG. 3 is an equivalent circuit diagram illustrating an electrical configuration of a pixel according to the first embodiment. It is a fragmentary sectional view of the display part of the electrophoretic display device concerning a 1st embodiment. It is a schematic diagram which shows the structure of the microcapsule which concerns on 1st Embodiment. It is a top view which shows an example of the image containing a line image. It is a schematic diagram which shows the 1st display control process which concerns on 1st Embodiment. It is a schematic diagram which shows the 2nd display control process which concerns on 1st Embodiment. It is a mimetic diagram showing the 1st display control process concerning a 2nd embodiment. It is a perspective view which shows the structure of the electronic paper which is an example of the electronic device to which the electro-optical device is applied. It is a perspective view which shows the structure of the electronic notebook which is an example of the electronic device to which the electro-optical apparatus is applied.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the following embodiments, an electrophoretic display device, which is an example of an electro-optical device according to the invention, is taken as an example.

<First Embodiment>
The electrophoretic display device according to the first embodiment will be described with reference to FIGS.

  First, the overall configuration of the electrophoretic display device according to the present embodiment will be described with reference to FIGS. 1 and 2.

  FIG. 1 is a block diagram showing the overall configuration of the electrophoretic display device according to this embodiment.

  In FIG. 1, the electrophoretic display device 1 according to the present embodiment includes a display unit 3, a controller 10, a scanning line driving circuit 60, a data line driving circuit 70, and a common potential supply circuit 220. The controller 10 is an example of an “electro-optical device control device” according to the present invention. In addition, the scanning line driving circuit 60, the data line driving circuit 70, and the common potential supply circuit 220 constitute an example of the “driving unit” according to the present invention.

  In the display unit 3, m rows × n columns of pixels 20 are arranged in a matrix (in a two-dimensional plane). The display unit 3 includes m scanning lines 40 (that is, scanning lines Y1, Y2,..., Ym) and n data lines 50 (that is, data lines X1, X2,..., Xn). It is provided so as to cross each other. Specifically, the m scanning lines 40 extend in the row direction (that is, the X direction), and the n data lines 50 extend in the column direction (that is, the Y direction). The pixels 20 are arranged corresponding to the intersections of the m scanning lines 40 and the n data lines 50.

  The controller 10 controls operations of the scanning line driving circuit 60, the data line driving circuit 70, and the common potential supply circuit 220. For example, the controller 10 supplies timing signals such as a clock signal and a start pulse to each circuit.

  The scanning line driving circuit 60 sequentially supplies a scanning signal in a pulse manner to each of the scanning lines Y1, Y2,..., Ym under the control of the controller 10.

  The data line driving circuit 70 supplies data signals to the data lines X1, X2,..., Xn under the control of the controller 10. The data signal takes one of a reference potential GND (for example, 0 V), a high potential VH (for example, +15 V), or a low potential VL (for example, −15 V). In the present embodiment, basically, a data signal having a low potential VL is supplied to the pixel 20 that should display black, and a data signal having a high potential VH to the pixel 20 that should display white. Is supplied.

  The common potential supply circuit 220 supplies a common potential Vcom (in this embodiment, the same potential as the reference potential GND) to the common potential line 93. Note that the common potential Vcom is a potential different from the reference potential GND within a range in which no voltage is substantially generated between the counter electrode 22 supplied with the common potential Vcom and the pixel electrode 21 supplied with the reference potential GND. It may be.

  Note that various signals are input to and output from the controller 10, the scanning line driving circuit 60, the data line driving circuit 70, and the common potential supply circuit 220, but descriptions of those that are not particularly related to the present embodiment are omitted. .

  FIG. 2 is an equivalent circuit diagram illustrating the electrical configuration of the pixel.

  In FIG. 2, the pixel 20 includes a pixel switching transistor 24, a pixel electrode 21, a counter electrode 22, an electrophoretic element 23, and a storage capacitor 27.

  The pixel switching transistor 24 is composed of, for example, an N-type transistor. The pixel switching transistor 24 has a gate electrically connected to the scanning line 40, a source electrically connected to the data line 50, and a drain electrically connected to the pixel electrode 21 and the storage capacitor 27. It is connected to the. The pixel switching transistor 24 is configured to pulse a data signal supplied from the data line driving circuit 70 (see FIG. 1) via the data line 50 via the scanning line 40 from the scanning line driving circuit 60 (see FIG. 1). Are output to the pixel electrode 21 and the storage capacitor 27 at a timing corresponding to the scanning signal supplied to the pixel.

  A data signal is supplied to the pixel electrode 21 from the data line driving circuit 70 through the data line 50 and the pixel switching transistor 24. The pixel electrode 21 is disposed so as to face the counter electrode 22 via the electrophoretic element 23.

  The counter electrode 22 is electrically connected to a common potential line 93 to which a common potential Vcom is supplied.

  The electrophoretic element 23 is composed of a plurality of microcapsules each containing electrophoretic particles.

  The storage capacitor 27 is composed of a pair of electrodes arranged opposite to each other with a dielectric film therebetween, one electrode is electrically connected to the pixel electrode 21 and the pixel switching transistor 24, and the other electrode is a common potential line 93. Is electrically connected. The data signal can be maintained for a certain period by the storage capacitor 27.

  Next, a specific configuration of the display unit of the electrophoretic display device according to the present embodiment will be described with reference to FIGS. 3 and 4.

  FIG. 3 is a partial cross-sectional view of the display unit of the electrophoretic display device according to this embodiment.

  In FIG. 3, the display unit 3 is configured such that an electrophoretic element 23 is sandwiched between an element substrate 28 and a counter substrate 29. In the present embodiment, description will be made on the assumption that an image is displayed on the counter substrate 29 side.

  The element substrate 28 is a substrate made of, for example, glass or plastic. Although not shown here, the pixel switching transistor 24, the storage capacitor 27, the scanning line 40, the data line 50, the common potential line 93, and the like described above with reference to FIG. 2 are formed on the element substrate 28. A laminated structure is formed. A plurality of pixel electrodes 21 are provided in a matrix on the upper layer side of the stacked structure.

  The counter substrate 29 is a transparent substrate made of, for example, glass or plastic. On the surface of the counter substrate 29 facing the element substrate 28, the counter electrode 22 is formed in a solid shape so as to face the plurality of pixel electrodes 9a. The counter electrode 22 is made of a transparent conductive material such as magnesium silver (MgAg), indium / tin oxide (ITO), indium / zinc oxide (IZO).

  The electrophoretic element 23 is an example of the “electro-optical material” according to the present invention, and includes a plurality of microcapsules 80 each including electrophoretic particles. For example, the binder 30 and the adhesive layer 31 made of a resin or the like. Thus, the element substrate 28 and the counter substrate 29 are fixed. In the electrophoretic display device 1 according to the present embodiment, in the manufacturing process, an electrophoretic sheet in which the electrophoretic element 23 is previously fixed to the counter substrate 29 side by the binder 30 is separately manufactured, such as the pixel electrode 21. It is constituted by being bonded by an adhesive layer 31 to the element substrate 28 side on which is formed.

  One or a plurality of microcapsules 80 are sandwiched between the pixel electrode 21 and the counter electrode 22, and are arranged in one pixel 20 (in other words, with respect to one pixel electrode 21).

  FIG. 4 is a schematic diagram showing the configuration of the microcapsule. In addition, in FIG. 4, the cross section of the microcapsule is shown typically.

  In FIG. 4, the microcapsule 80 is formed by enclosing a dispersion medium 81, a plurality of white particles 82, and a plurality of black particles 83 inside a coating 85. The microcapsule 80 is formed in a spherical shape having a particle size of about 50 μm, for example.

  The coating 85 functions as an outer shell of the microcapsule 80 and is formed of a translucent polymer resin such as acrylic resin such as polymethyl methacrylate and polyethyl methacrylate, urea resin, gum arabic, and gelatin. .

  The dispersion medium 81 is a medium for dispersing the white particles 82 and the black particles 83 in the microcapsules 80 (in other words, in the coating 85). Examples of the dispersion medium 81 include water, alcohol solvents such as methanol, ethanol, isopropanol, butanol, octanol, and methyl cellosolve, various esters such as ethyl acetate and butyl acetate, and ketones such as acetone, methyl ethyl ketone, and methyl isobutyl ketone. , Aliphatic hydrocarbons such as pentane, hexane and octane, alicyclic hydrocarbons such as cyclohexane and methylcyclohexane, benzene, toluene, xylene, hexylbenzene, hebutylbenzene, octylbenzene, nonylbenzene, decylbenzene, undecyl Aromatic hydrocarbons such as benzenes with long chain alkyl groups such as benzene, dodecylbenzene, tridecylbenzene, tetradecylbenzene, etc., halo such as methylene chloride, chloroform, carbon tetrachloride, 1,2-dichloroethane, etc. Emissions of hydrocarbons, carboxylate or other oils may be used singly or as a mixture. In addition, a surfactant may be added to the dispersion medium 81.

  The white particles 82 are particles (polymer or colloid) made of a white pigment such as titanium dioxide, zinc white (zinc oxide), and antimony trioxide, and are negatively charged, for example.

  The black particles 83 are particles (polymer or colloid) made of a black pigment such as aniline black or carbon black, and are positively charged, for example.

  For this reason, the white particles 82 and the black particles 83 can move in the dispersion medium 81 by the electric field generated by the potential difference between the pixel electrode 21 and the counter electrode 22.

  These pigments include electrolytes, surfactants, metal soaps, resins, rubbers, oils, varnishes, charge control agents composed of particles such as compounds, titanium-based coupling agents, aluminum-based coupling agents, silanes as necessary. A dispersant such as a system coupling agent, a lubricant, a stabilizer, and the like can be added.

  3 and 4, when a voltage is applied between the pixel electrode 21 and the counter electrode 22 so that the potential of the counter electrode 22 is relatively high, the positively charged black particles 83 are While being attracted to the pixel electrode 21 side in the microcapsule 80 by the Coulomb force, the negatively charged white particles 82 are attracted to the counter electrode 22 side in the microcapsule 80 by the Coulomb force. As a result, the white particles 82 gather on the display surface side (that is, the counter electrode 22 side) in the microcapsule 80, and the color of the white particles 82 (that is, white) is displayed on the display surface of the display unit 3. Will be displayed. Conversely, when a voltage is applied between the pixel electrode 21 and the counter electrode 22 so that the potential of the pixel electrode 21 becomes relatively high, the negatively charged white particles 82 are generated by the Coulomb force. While attracted to the electrode 21 side, the positively charged black particles 83 are attracted to the counter electrode 22 side by Coulomb force. As a result, the black particles 83 are collected on the display surface side of the microcapsule 80, and the color of the black particles 83 (that is, black) is displayed on the display surface of the display unit 3.

  In addition, red, green, blue, etc. can be displayed by replacing the pigment used for the white particle 82 and the black particle 83 with pigments, such as red, green, and blue, for example.

  Next, a method for controlling the electrophoretic display device according to the present embodiment will be described with reference to FIGS.

  FIG. 5 is a plan view illustrating an example of an image including a line image.

  In the following, the control method of the electrophoretic display device 1 described above, ie, the case where the image P including the line images Lb and Lw as shown in FIG. 5 is displayed on the display unit 3 (see FIG. 1), that is, A control method in which the controller 10 controls the scanning line driving circuit 60, the data line driving circuit 70, and the common potential supply circuit 220 will be described. The image P is a two-gradation image composed of two gradations of black and white. Hereinafter, the scanning line driving circuit 60, the data line driving circuit 70, and the common potential supply circuit 220 are collectively referred to as a “driving unit” as appropriate.

  As shown in FIG. 5, the image P includes a black line image Lb, a white background image Bw that is the background of the line image Lb, a white line image Lw, and a black background that is the white background. Image Bb is included. The line images Lb and Lw have a line width corresponding to one pixel. That is, the line width WLb of the line image Lb and the line width WLw of the line image Lw are almost the same as the width of the pixel electrode 21.

  In the present embodiment, when the image to be displayed includes a line image having a line width corresponding to one pixel, the first display control step and the second display control step are sequentially performed as follows. Thus, an image to be displayed is displayed on the display unit 3.

  That is, when the image P including line images Lb and Lw each having a line width corresponding to one pixel is displayed on the display unit 3, the controller 10 sequentially performs the first and second display control steps. . Note that the controller 10 determines whether or not the image to be displayed includes a line image having a line width corresponding to one pixel (in other words, narrower than a predetermined width slightly larger than the line width corresponding to one pixel). Whether or not a line image is included is determined based on the image data. When it is determined that the image to be displayed includes a line image having a line width corresponding to one pixel, the controller 10 performs the first and second display control steps. In the present embodiment, an example in which the first and second display control steps are sequentially performed when a line image having a line width corresponding to one pixel is included in the image to be displayed is described. In a power image, a line width equal to or smaller than a line width corresponding to 2 pixels (that is, a line width twice as large as a line width corresponding to 1 pixel) or a line width corresponding to 3 pixels (that is, a line width corresponding to 1 pixel) The first and second display controls when a line image having a line width equal to or smaller than a line width corresponding to a plurality of times the width of one pixel 20 is included, such as a line width equal to or less than three times the line width). The steps may be performed in order.

  FIG. 6 is a schematic diagram showing a first display control process according to the present embodiment. FIG. 6A shows the state of the pixel 20 corresponding to the black line image Lb and the white background image Bw in the first display control step according to this embodiment, and FIG. The state of the pixel 20 corresponding to the white line image Lw and the black background image Bb in the 1st display control process which concerns on embodiment is shown.

  5 and 6, in the first display control step, among the pixels 20 (see FIG. 1) for m rows × n columns arranged in the display unit 3, the pixels in the pixels 20 corresponding to the white background image Bw. A low potential VL (for example, −15 V) is supplied to each of the electrode 21Bw (see FIG. 6A) and the pixel electrode 21Lw (see FIG. 6B) in the pixel 20 corresponding to the white line image Lw. Each of the pixel electrode 21Bb (see FIG. 6B) in the pixel 20 corresponding to the black background image Bb and the pixel electrode 21Lb (see FIG. 6A) in the pixel 20 corresponding to the black line image Lb. The drive unit is controlled by the controller 10 so that a high potential VH (for example, +15 V) is supplied. That is, in the first display control step, a low potential (for example, −15 V) is supplied to the pixel electrode 21 (that is, the pixel electrode 21Bw and the pixel electrode 21Lw) in the pixel 20 that should display white, and black should be displayed. The drive unit is controlled by the controller 10 so that a high potential (for example, +15 V) is supplied to the pixel electrode 21 (that is, the pixel electrode 21Bb and the pixel electrode 21Lb) in the pixel 20. The counter electrode 22 is supplied with a common potential Vcom (in this embodiment, for example, a reference potential GND of 0 V).

  Therefore, as shown in FIG. 6A, in the pixel 20 corresponding to the white background image Bw, an electric field EBw is generated from the counter electrode 22 toward the pixel electrode 21Bw, and the black particles 83 are attracted to the pixel electrode 21Bw side. The white particles 82 are attracted to the counter electrode 22 side and reach the counter electrode 22 while reaching the pixel electrode 21Bw. As a result, white is displayed on the pixel 20 corresponding to the white background image Bw. 6B, in the pixel 20 corresponding to the black background image Bb, an electric field EBb is generated from the pixel electrode 21Bb toward the counter electrode 22, and the black particles 83 are attracted to the counter electrode 22 side. As a result, the white particles 82 are attracted toward the pixel electrode 21Bb and reach the pixel electrode 21Bb. As a result, black is displayed on the pixel 20 corresponding to the black background image Bb. 6A, in the pixel 20 corresponding to the black line image Lb, the pixel electrode 21Lb in the pixel 20 and the pixel corresponding to the white background image Bw located adjacent to the pixel 20 Since a horizontal electric field (that is, an electric field from the pixel electrode 21Lb toward the pixel electrode 21Bw) Et1 is generated between the 20 pixel electrodes 21Bw, the magnitude of the electric field ELb generated between the pixel electrode 21Lb and the counter electrode 22 is It is smaller than the magnitudes of the electric field EBw and the electric field EBb. Here, the potential difference between the pixel electrode 21Lb and the pixel electrode 21Bw (that is, the difference between the high potential VH and the low potential VL, for example, 30 V) is the potential difference between the pixel electrode 21Lb and the counter electrode 22 (that is, the high potential VH and the reference potential). And the distance between the pixel electrode 21Lb and the pixel electrode 21Bw (that is, the distance between the pixel electrodes, for example, about 10 μm) is between the pixel electrode 21Lb and the counter electrode 22. Therefore, the magnitude of the electric field ELb from the pixel electrode 21Lb toward the counter electrode 22 is smaller than the magnitude of the horizontal electric field Et1 (that is, corresponding to the black line image Lb). In the pixel 20, the horizontal electric field Et1 works predominantly with respect to the black particles 83 and the white particles 82). Therefore, in the pixels 20 corresponding to the black line image Lb, the black particles 83 are attracted to the counter electrode 22 side, but the black particles 83 do not reach the counter electrode 22 and the white particles 82 are attracted to the pixel electrode 21Lb side. However, it does not reach the pixel electrode 21Lb. 6B, in the pixel 20 corresponding to the white line image Lw, the pixel electrode 21Lw in the pixel 20 and the pixel corresponding to the black background image Bb located adjacent to the pixel 20 Since a horizontal electric field (that is, an electric field from the pixel electrode 21Bb toward the pixel electrode 21Lw) Et2 is generated between the 20 pixel electrodes 21Bb, the magnitude of the electric field ELw generated between the pixel electrode 21Lw and the counter electrode 22 is It is smaller than the magnitude of the electric field EBw or the electric field EBb. Here, the potential difference between the pixel electrode 21Lw and the pixel electrode 21Bb (that is, the difference between the low potential VL and the high potential VH, for example, 30 V) is the potential difference between the pixel electrode 21Lw and the counter electrode 22 (that is, the low potential VL and the reference potential). And the distance between the pixel electrode 21Lw and the pixel electrode 21Bb (that is, the distance between the pixel electrodes, for example, about 10 μm) is between the pixel electrode 21Lw and the counter electrode 22. Therefore, the magnitude of the electric field ELw going from the pixel electrode 21Lw to the counter electrode 22 is smaller than the magnitude of the horizontal electric field Et2 (that is, corresponding to the white line image Lw). In the pixel 20, the horizontal electric field Et2 works predominantly with respect to the black particles 83 and the white particles 82). Therefore, in the pixel 20 corresponding to the white line image Lw, the white particles 82 are attracted to the counter electrode 22 side, but do not reach the counter electrode 22, and the black particles 83 are attracted to the pixel electrode 21Lw side. 21Lw is not reached.

  After such a first display control step is performed, the following second display control step is performed.

  FIG. 7 is a schematic diagram showing a second display control process according to the present embodiment. FIG. 7A shows the state of the pixel 20 corresponding to the black line image Lb and the white background image Bw in the second display control step according to the present embodiment, and FIG. The state of the pixel 20 corresponding to the white line image Lw and the black background image Bb in the 2nd display control process which concerns on embodiment is shown.

  5 and 7, in the second display control step, among the pixels 20 (see FIG. 3) for m rows × n columns arranged in the display unit 3, the pixels in the pixels 20 corresponding to the white background image Bw. The reference potential GND is supplied to each of the electrode 21Bw (see FIG. 7A) and the pixel electrode 21Bb (see FIG. 7B) in the pixel 20 corresponding to the black background image Bb, and the black line image A high potential VH (for example, +15 V) is supplied to the pixel electrode 21Lb (see FIG. 7A) in the pixel 20 corresponding to Lb, and the pixel electrode 21Lw (see FIG. The drive unit is controlled by the controller 10 so that the low potential VL (for example, −15 V) is supplied to (b). That is, in the second display control step, the reference potential GND is supplied to the pixel electrode 21 (that is, the pixel electrode 21Bw and the pixel electrode 21Bb) in the pixel 20 on which the background images Bw and Bb are to be displayed, and the line images Lb and Lw The pixel electrode 21 (that is, the pixel electrode 21Lb and the pixel electrode 21Lb) in the pixel 20 to be displayed has a high potential VH (for example, +15 V) or a low potential VL (for example, −15 V) depending on the line image to be displayed by the pixel 20. ) Is supplied by the controller 10. The counter electrode 22 is supplied with a common potential Vcom (in this embodiment, for example, a reference potential GND of 0 V).

  That is, in the second display control step, the reference potential GND is supplied to the pixel electrodes 21Bw and 21Rb corresponding to the background image, and the high potential VH is supplied to the pixel electrode 21Lb corresponding to the line image Lb. The low potential VL is supplied to the pixel electrode 21Lw corresponding to Lw.

  Therefore, as shown in FIG. 7, in each of the pixel 20 corresponding to the white background image Bw and the pixel 20 corresponding to the black background image Bb, the pixel electrode 21 (that is, the pixel electrode 21Bw or 21Bb) and the counter electrode Therefore, the black particles 83 and the white particles 82 are maintained in almost the same state as after the first display control step described above with reference to FIG. 6 is performed. The 7A, in the pixel 20 corresponding to the black line image Lb, an electric field ELb is generated from the pixel electrode 21Lb toward the counter electrode 22, and the black particles 83 are attracted to the counter electrode 22 side. As a result, the white particles 82 are attracted toward the pixel electrode 21Lb and reach the pixel electrode 21Lb. As a result, black is displayed on the pixel 20 corresponding to the black line image Lb. Further, as shown in FIG. 7B, in the pixel 20 corresponding to the white line image Lw, an electric field ELw is generated from the counter electrode 22 toward the pixel electrode 21Lw, and the black particles 83 are attracted to the pixel electrode 21Lw side. As a result, the white particles 82 are attracted to the counter electrode 22 side and reach the counter electrode 22 while reaching the pixel electrode 21Lw. As a result, white is displayed on the pixels 20 corresponding to the white line image Lw.

  Here, the potential difference between the pixel electrode 21Lb and the pixel electrode 21Bw in the second display control step (that is, the difference between the high potential VH and the reference potential GND, for example, 15 V) is the same as the pixel electrode 21Lb and the pixel electrode in the first display control step. Since the potential difference with respect to 21Bw (that is, the difference between the high potential VH and the low potential VL, for example, 30V) is smaller, the lateral electric field from the pixel electrode 21Lb toward the pixel electrode 21Bw is smaller than in the first display control step. Therefore, according to the second display control step, in the pixel 20 corresponding to the black line image Lb, the black particles 83 can surely reach the counter electrode 22, and the white particles 82 can be reliably reached the pixel electrode 21Lb. Can be reached. Therefore, black can be reliably displayed on the pixels 20 corresponding to the black line image Lb. As a result, the black line image Lb can be reliably displayed on the display unit 3. Similarly, the potential difference between the pixel electrode 21Lw and the pixel electrode 21Bb in the second display control step (that is, the difference between the low potential VL and the reference potential GND, for example, 15 V) is the same as the pixel electrode 21Lw and the pixel electrode in the first display control step. Since the potential difference with respect to 21Bb (that is, the difference between the low potential VL and the high potential VH, for example, 30 V) is smaller, the lateral electric field from the pixel electrode 21Bb toward the pixel electrode 21Lw is smaller than in the first display control step. Therefore, according to the second display control step, in the pixel 20 corresponding to the white line image Lw, the white particles 82 can surely reach the counter electrode 22 and the black particles 8 can be reliably delivered to the pixel electrode 21Lb. Can be reached. Therefore, white can be reliably displayed on the pixels 20 corresponding to the white line image Lw. As a result, the white line image Lw can be reliably displayed on the display unit 3.

  As a result, the electrophoretic display device 1 according to the present embodiment can reliably display the image P including the line images Lb and Lw having a line width corresponding to the width of one pixel on the display unit 3. That is, according to the present embodiment, for example, the line widths of the line images displayed as the line images Lb and Lw on the display unit 3 are thinner than the line widths of the line images Lb and Lw to be displayed, It is possible to avoid a situation in which the line images Lb and Lw to be displayed are hardly or not displayed at all.

  As described above, according to the present embodiment, a line image having a thin line width such as a line width corresponding to the width of one pixel can be reliably displayed on the display unit 3, and a high-quality image is displayed. Can be made.

Second Embodiment
An electrophoretic display device according to a second embodiment will be described with reference to FIG.

  In the electrophoretic display device according to the second embodiment, the controller 10 described above controls the drive unit (specifically, the first display control step described above with reference to FIG. 6) is the same as the first described above. Different from the electrophoretic display device 1 according to the embodiment. In other respects, the electrophoretic display device according to the second embodiment is configured in substantially the same manner as the electrophoretic display device 1 according to the first embodiment described above.

  FIG. 8 is a schematic diagram illustrating a first display control process according to the second embodiment. FIG. 8A shows the state of the pixel 20 corresponding to the black line image Lb and the white background image Bw in the first display control step according to the second embodiment. FIG. The state of the pixel 20 corresponding to the white line image Lw and the black background image Bb in the 2nd display control process which concerns on 2nd Embodiment is shown. In FIG. 8, the same components as those in the first embodiment shown in FIGS. 1 to 7 are denoted by the same reference numerals, and the description thereof will be omitted as appropriate.

  5 and 8, in the first display control step, among the pixels 20 (see FIG. 1) for m rows × n columns arranged in the display unit 3, the pixels in the pixels 20 corresponding to the white background image Bw. A low potential VL (for example, −15 V) is supplied to the electrode 21Bw (see FIG. 8A), and a high potential is applied to the pixel electrode 21Bb (see FIG. 8B) in the pixel 20 corresponding to the black background image Bb. VH (for example, + 15V) is supplied, and the pixel electrode 21L in the pixel 20 corresponding to the black line image Lb and the pixel electrode 21Lw in the pixel 20 corresponding to the white line image Lw (see FIG. 8B). The drive unit is controlled by the controller 10 so that a reference potential GND (for example, 0 V) is supplied to each. The counter electrode 22 is supplied with a common potential Vcom (in this embodiment, for example, a reference potential GND of 0 V).

  Therefore, as shown in FIG. 8A, in the pixel 20 corresponding to the white background image Bw, the electric field EBw is generated from the counter electrode 22 toward the pixel electrode 21Bw, and the black particles 83 are attracted to the pixel electrode 21Bw side. The white particles 82 are attracted to the counter electrode 22 side and reach the counter electrode 22 while reaching the pixel electrode 21Bw. As a result, white is displayed on the pixel 20 corresponding to the white background image Bw. 8B, in the pixel 20 corresponding to the black background image Bb, an electric field EBb is generated from the pixel electrode 21Bb toward the counter electrode 22, and the black particles 83 are attracted to the counter electrode 22 side. As a result, the white particles 82 are attracted toward the pixel electrode 21Bb and reach the pixel electrode 21Bb. As a result, black is displayed on the pixel 20 corresponding to the black background image Bb. Further, as shown in FIG. 8A, in the pixel 20 corresponding to the black line image Lb, there is little or no potential difference between the pixel electrode 21Lb and the counter electrode 22, so that the black particles 83 and the white particles 82 moves to the pixel electrode 21Lb side and the counter electrode 22 side due to the influence of the electric field EBw generated in the adjacent pixel 20, but does not reach the pixel electrode 21Lb or the counter electrode 22. Similarly, as shown in FIG. 8B, in the pixel 20 corresponding to the white line image Lb, there is little or no potential difference between the pixel electrode 21Lw and the counter electrode 22. The particles 82 move to the pixel electrode 21Lw side and the counter electrode 22 side due to the influence of the electric field EBb generated in the adjacent pixel 20, but do not reach the pixel electrode 21Lw or the counter electrode 22.

  After such a first display control step is performed, a second display control step is performed as in the first embodiment described above.

  In the first display control process according to the second embodiment shown in FIG. 8, in particular, the reference potential GND (for example, 0 V) is applied to the pixel electrode 21 (that is, the pixel electrodes Lb and Lw) in the pixel 20 corresponding to the line images Lb and Lw. Is supplied. That is, in the first display control process according to the present embodiment, particularly, little or no voltage is applied between the pixel electrode 21 and the counter electrode 22 in the pixel 20 corresponding to the line image. Therefore, when a voltage is applied between the pixel electrode 21 and the counter electrode 22 in the pixel 20 corresponding to the line image in the second display control step (see FIG. 7) performed after the first display control step, the pixel electrode It can be suppressed that the black particles 83 and the white particles 82 are damaged or deteriorated due to excessive application of a voltage between 21 and the counter electrode 22. Therefore, according to this embodiment, the reliability of the electrophoretic display device can be improved.

<Electronic equipment>
Next, electronic devices to which the above-described electrophoretic display device is applied will be described with reference to FIGS. Below, the case where the electrophoretic display device described above is applied to electronic paper and electronic notebook is taken as an example.

  FIG. 9 is a perspective view illustrating a configuration of the electronic paper 1400.

  As shown in FIG. 9, the electronic paper 1400 includes the electrophoretic display device according to the above-described embodiment as a display unit 1401. The electronic paper 1400 has flexibility, and includes a main body 1402 formed of a rewritable sheet having the same texture and flexibility as conventional paper.

  FIG. 10 is a perspective view illustrating a configuration of the electronic notebook 1500.

  As shown in FIG. 10, an electronic notebook 1500 is obtained by bundling a plurality of electronic papers 1400 shown in FIG. 10 and sandwiching them between covers 1501. The cover 1501 includes display data input means (not shown) for inputting display data sent from an external device, for example. Thereby, according to the display data, the display content can be changed or updated while the electronic paper is bundled.

  Since the electronic paper 1400 and the electronic notebook 1500 described above include the electrophoretic display device according to the above-described embodiment, low power consumption and high-quality image display can be performed.

  In addition to these, the electrophoretic display device according to the present embodiment described above can be applied to a display unit of an electronic device such as a wristwatch, a mobile phone, or a portable audio device.

  In addition to the electrophoretic display device, the present invention can also be applied to a display device using an electronic powder fluid.

  The present invention is not limited to the above-described embodiments, and can be appropriately changed without departing from the spirit or idea of the invention that can be read from the claims and the entire specification, and an electro-optical device with such a change. The control method, electro-optical device control device, electro-optical device, and electronic apparatus are also included in the technical scope of the present invention.

  DESCRIPTION OF SYMBOLS 3 ... Display part, 10 ... Controller, 20 ... Pixel, 21 ... Pixel electrode, 22 ... Counter electrode, 28 ... Element substrate, 29 ... Counter substrate, 60 ... Scanning line drive circuit, 70 ... Data line drive circuit, 82 ... White Particles 83... Black particles 220. Common potential supply circuit.

Claims (6)

A display unit including a pixel electrode facing each other and a plurality of pixels each having an electro-optic material between the counter electrodes, and driving for applying a voltage between the pixel electrode and the counter electrode according to an image to be displayed on the display unit A control method for controlling an electro-optical device comprising:
When the image to be displayed includes a line image having a line width smaller than a predetermined width, a second pixel located adjacent to the first pixel corresponding to the line image among the plurality of pixels. By controlling the driving unit so that one of a high potential higher than a reference potential and a low potential lower than the reference potential is supplied to the pixel electrode, the first pixel is supplied to the second pixel. A first display control step for displaying a key;
After the first display control step, the reference potential is supplied to the pixel electrode in the second pixel, and the one potential of the high potential and the low potential is applied to the pixel electrode in the first pixel. A second display control step of causing the first pixel to display a second gradation different from the first gradation by controlling the driving unit so that the other potential different from the first potential is supplied. A control method for an electro-optical device.   2. The control of the electro-optical device according to claim 1, wherein the first display control step controls the driving unit so that the other potential is supplied to the pixel electrode in the first pixel. Method.   2. The method of controlling an electro-optical device according to claim 1, wherein the first display control step controls the driving unit so that the reference potential is supplied to the pixel electrode in the first pixel. . A display unit including a pixel electrode facing each other and a plurality of pixels each having an electro-optic material between the counter electrodes, and driving for applying a voltage between the pixel electrode and the counter electrode according to an image to be displayed on the display unit A control device for controlling an electro-optical device comprising:
When the image to be displayed includes a line image having a line width smaller than a predetermined width, a second pixel located adjacent to the first pixel corresponding to the line image among the plurality of pixels. By controlling the driving unit so that one of a high potential higher than a reference potential and a low potential lower than the reference potential is supplied to the pixel electrode, the first pixel is supplied to the second pixel. First display control means for displaying a key;
After the first gradation is displayed on the second pixel by the first display control means, the reference potential is supplied to the pixel electrode in the second pixel, and the pixel electrode in the first pixel is supplied to the pixel electrode. By controlling the driving unit so that the other potential different from the one potential of the high potential and the low potential is supplied, the first pixel is different from the first gradation. A control device for an electro-optical device, comprising: second display control means for displaying two gradations.   An electro-optical device comprising the control device for an electro-optical device according to claim 4.   An electronic apparatus comprising the electro-optical device according to claim 5.

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