JP5512409B2 - Electrophoretic display device and driving method thereof - Google Patents

Description

  The present invention relates to an electrophoretic display device that reversibly changes a visual state by applying an electric field to charged particles and a driving method thereof.

  In recent years, with the development of information equipment, demands for reducing power consumption, thinning, and flexibility of display devices are increasing. There is an electrophoretic display device as one of display devices that meet such a demand. In an electrophoretic display device, two substrates at least one of which are transparent are arranged to face each other through a spacer, pixel electrodes are arranged in a matrix on one substrate, and common electrodes are arranged on the other substrate. A display panel is formed by charging a display liquid in which charged particles, which are charged to a charge or a negative charge and colored in different colors, are dispersed in a dispersion medium between substrate electrodes, and an electric field is applied between the substrate electrodes. A desired display is to be obtained (see, for example, Patent Document 1).

  Since the electrophoretic display device displays an image by moving charged particles, the writing time required to display the image tends to be longer than that of the liquid crystal. In the case of high-quality display such as an electronic book, the tendency for the writing time to be long is remarkable. On the other hand, when the page is scrolled or enlarged / reduced, the screen needs to be switched at high speed. For this reason, an operator who has performed an operation that requires high-speed image switching on the electrophoretic display device may cause discomfort due to the slow image switching speed.

  Therefore, a driving method for realizing high-speed image switching in an electrophoretic display device has been proposed (for example, see Patent Document 2). In the driving method described in Patent Document 2, only a reset is performed by a signal for changing the screen display, and after the change is confirmed, writing is performed to display the screen.

US Pat. No. 3,612,758 JP 2010-45527 A

  However, the driving method described in Patent Document 2 described above has little effect of reducing the time because the screen rewriting time itself is not changed.

  The present invention has been made in view of such problems, and realizes high-speed switching of a display image at the time of screen operation such as scrolling and enlargement / reduction, and can display a high-quality image as a still image. An object of the present invention is to provide an electrophoretic display device and a driving method thereof.

An electrophoretic display device of the present invention includes a pair of substrates that are arranged to face each other with a space having a predetermined width and at least one of which is light transmissive, and a plurality of substrates formed on the substrate surface of one of the pair of substrates. Two types of pixel electrodes, a common electrode formed on the substrate surface of the other of the pair of substrates so as to face the plurality of pixel electrodes, and different colors and polarities enclosed between the pair of substrates A liquid material in which charged particles are dispersed; and a drive circuit that generates an address pulse that generates a potential difference that moves the charged particles between the pixel electrode and the common electrode. In the fixed display, the same image writing pulse is repeatedly applied a predetermined number of times during image formation, and in the switching display in which the screen is continuously switched, the first of the writing pulses is formed during image formation on each switching screen. Only by applying pulses to exit the image forming, the second screen from the first screen, and the screen is switched in succession to the third screen is a screen immediately before the end of the second screen is the switching display, wherein When the display is switched from the second screen to the third screen and the switching display is completed, the pixels whose color display is continuously switched from the first screen to the second screen and the third screen are as follows. In the third screen, the display of the color is switched by applying only the number of pulses that is the same number of times as the number of pulses applied in the second screen, and from the first screen in the second screen. for the pixels display is switched to the color from the second screen in the color display the third screen without switching of the write pulses of the same predetermined number of times and the fixed display is characterized Rukoto applied.

  With this configuration, in fixed display where the screen does not change, the same image writing pulse is repeatedly applied a predetermined number of times during image formation, so a high-quality (for example, high contrast) image can be realized, and the screen can be switched continuously. In the display, only the first few pulses of the writing pulse are applied during image formation on each switching screen, so that the image quality is slightly reduced, but high-speed screen switching can be realized.

  In the electrophoretic display device of the present invention, the driving circuit may apply a shaking pulse in which the polarity of the voltage is alternately reversed in a short time before the writing pulse is applied. As a result, charged particles that have been left for a long time and become large lumps by applying a shaking pulse can be loosened, and can be easily moved by a write pulse applied thereafter.

  In the electrophoretic display device of the present invention, a shaking pulse is applied to the whole of the plurality of pixels composed of the plurality of pixel electrodes, the common electrode, and the liquid material, and the pixels are sequentially scanned with the writing pulse. Also good.

  In the electrophoretic display device of the present invention, a shaking pulse is applied to a pixel to be rewritten among the plurality of pixel electrodes, the common electrode, and the liquid crystal display unit, and the pixels May be sequentially scanned with the address pulse.

Also, the driving method of the electrophoretic display device of the present invention includes a pair of substrates opposed to each other with a space having a predetermined width and at least one having light transparency, and a substrate surface of one of the pair of substrates. A plurality of pixel electrodes formed, a common electrode formed on the substrate surface of the other substrate of the pair of substrates so as to face the plurality of pixel electrodes, and a color and polarity enclosed between the pair of substrates Electrophoretic display comprising: a liquid material in which two types of charged particles having different particle sizes are dispersed; and a drive circuit for generating an address pulse for generating a potential difference for moving the charged particles between the pixel electrode and the common electrode In a fixed display where the screen does not change in the driving method of the apparatus, the same image writing pulse is repeatedly applied a predetermined number of times during image formation, and each switching screen is switched in a switching display in which the screen is switched continuously. Image forming time on only the first few pulses of the write pulse is applied to end the image formation, the second screen from the first screen, and switching in succession the screen to the third screen, the second screen the display switching of When the display is switched from the second screen to the third screen and the switching display is finished, the color display is performed from the first screen to the second screen and the third screen. For the pixels to be continuously switched, the display of the color is switched by applying only the number of pulses that is the same number of times as the number of pulses applied on the second screen in the third screen. The same predetermined number of writing pulses as in the fixed display are applied to the pixels in which the color display is not switched from the first screen on the screen and the color display is switched from the second screen on the third screen. And wherein the Rukoto.

  According to the present invention, high-speed switching of a display image at the time of screen operation such as scrolling and enlargement / reduction can be realized, and a high-quality image can be displayed as a still image.

1 is a block diagram showing the overall configuration of an electrophoretic display device according to an embodiment FIG. 2 is an equivalent circuit diagram illustrating an electrical configuration of a pixel of the electrophoretic display device according to the embodiment. The fragmentary sectional view of the display part of the electrophoretic display device concerning an embodiment Schematic diagram showing the display of the electrophoretic display device according to the embodiment Schematic internal view of the display unit when displaying on the electrophoretic display device according to the embodiment Schematic diagram showing the transition of the write pulse in the process of switching from the first screen to the third screen by scrolling the screen The figure which shows the measurement result by the oscilloscope of the voltage waveform concerning each pixel when black display moves in embodiment

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.
FIG. 1 is an overall configuration diagram of an electrophoretic display device according to an embodiment of the present invention. The electrophoretic display device 1 includes a display unit 2 in which pixels are arranged in a matrix, a data line driving circuit 3 that supplies an image signal to the display unit 2, and a scanning line driving circuit 4 that supplies a scanning signal to the display unit 2. A common potential supply circuit 5 that applies a common potential to each pixel of the display unit 2 and a controller 6 that controls the operation of the entire apparatus. The data line driving circuit 3, the scanning line driving circuit 4, the common potential supply circuit 5, and the controller 6 constitute a driving circuit.

  The electrophoretic display device 1 receives an image operation request for a display image via the user interface unit 7. The image operation includes image scrolling on the display unit 2, image enlargement / reduction, and page turning for switching the display page at high speed or arbitrary speed. The user interface unit 7 converts the image operation content by the user into an image operation signal and supplies it to the controller 6. In the present specification, an operation of continuously switching the screen such as scrolling, enlargement / reduction, and page turning is referred to as screen switching, and an image operation signal at the time of screen switching is referred to as a screen switching signal. A screen switching signal is input from the start to the end of screen switching.

  The display unit 2 includes n data lines X1 to Xn extending in parallel in the row direction (X direction) from the data line driving circuit 3 and scanning lines so as to intersect these data lines X1 to Xn. From the drive circuit 4, m scanning lines Y1 to Ym extend in parallel in the column direction (Y direction). In the display unit 2, pixels 20 serving as pixels are formed at each intersection where the data lines (X1, X2,... Xn) and the scanning lines (Y1, Y2,... Ym) intersect. Thus, the display unit 2 has a plurality of pixels 20 arranged in an m × n matrix.

  The data line driving circuit 3 supplies an image signal to the data lines X1, X2,... Xn based on the timing signal supplied from the controller 6. The image signal takes a binary potential of a high potential VH (for example, 60 V) or a low potential VL (for example, 0 V). In the present embodiment, a low potential VL potential is supplied to the pixel 20 that should display white, and a high potential VH image signal is supplied to the pixel 20 that should display black.

  The scanning line driving circuit 4 sequentially supplies scanning signals to each of the scanning lines Y1, Y2,... Ym based on the timing signal supplied from the controller 6. A scanning signal is supplied to the pixel 20 to be driven.

  A common potential Vcom is applied from the common potential supply circuit 5 through the common potential line 11 to each pixel 20 constituting the display unit 2. The common potential Vcom may be a constant potential, or may change depending on, for example, the gradation to be written. In the present embodiment, as will be described later, the pixel 20 is supplied with the same potential as the common potential Vcom. This may be realized, for example, by setting the common potential Vcom output from the common potential supply circuit 5 to the same potential as the high potential VH or the low potential VL, or from the data line driving circuit 3 to the high potential VH. In addition to the low potential VL, another potential that is the same as the common potential Vcom may be supplied.

  The controller 6 supplies timing signals such as a clock signal and a start pulse to the data line driving circuit 3, the scanning line driving circuit 4, and the common potential supply circuit 5 to control the operation of each circuit. Specifically, before switching the screen, the controller 6 repeatedly applies the same image writing pulse to the pixel 20 a predetermined number of times to display a high contrast, and when a screen switching signal is input during the repetition, the screen switching operation is performed. During this, the number of repetitions is reduced to give priority to high-speed switching, and after completion of the screen switching operation, drive control is performed so that a predetermined number of write pulses are applied again to display high contrast.

  FIG. 2 is an equivalent circuit diagram illustrating an electrical configuration of the pixel 20. Since each pixel 20 arranged in a matrix on the display unit 2 has the same configuration, each unit constituting the pixel 20 will be described with a common reference numeral.

  The pixel 20 includes a pixel electrode 21, a common electrode 22, an electrophoretic element 23, a pixel switching transistor 24, and a storage capacitor 25. The pixel switching transistor 24 is composed of, for example, an N-type transistor. The gate of the pixel switching transistor 24 is electrically connected to the scanning line (Y1, Y2,... Ym) of the corresponding row. The source of the pixel switching transistor 24 is electrically connected to the data line (X1, X2,... Xm) of the corresponding column. The drain of the pixel switching transistor 24 is electrically connected to the pixel electrode 21 and the storage capacitor 25. The pixel switching transistor 24 receives the image signal supplied from the data line driving circuit 3 through the data lines X1, X2,... Xm, and the scanning lines (Y1, Y2,. Are output to the pixel electrode 21 and the storage capacitor 25 at a timing according to the scanning signal supplied in a pulse manner via the.

  An image signal is supplied to the pixel electrode 21 from the data line driving circuit 3 through the data lines X1, X2,... Xm and the pixel switching transistor 24. The pixel electrode 21 is disposed so as to face the common electrode 22 through the electrophoretic element 23. The common electrode 22 is electrically connected to the common potential line 11 to which the common potential Vcom is supplied.

  The electrophoretic element 23 is a liquid containing a plurality of electrophoretic particles, and is held between electrodes by a sealing material (not shown) so as not to leak out. The electrophoretic particles are positively charged black particles and negatively charged white particles described later.

  The storage capacitor 25 is made up 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 connected to the common potential line 11. Electrically connected. The image signal can be maintained for a certain period by the holding capacitor 25.

Here, a specific configuration of the display unit 2 of the electrophoretic display device 1 will be described.
FIG. 3 is a partial cross-sectional view of the display unit 2 in the electrophoretic display device 1. The display unit 2 is configured such that an element substrate 28 and a light-transmitting counter substrate 29 are arranged to face each other via a spacer (not shown), and the electrophoretic element 23 is sealed between the substrates. 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 on the element substrate 28, the pixel switching transistor 24, the storage capacitor 25, the scanning line (any one of Y, Y2,... Ym), data described above with reference to FIG. A stacked structure in which a line (any one of X1, X2,... Xn), a common potential line 11 and the like is formed is formed. A plurality of pixel electrodes 21 are provided in a matrix on the upper layer side of the laminated structure.

  The counter substrate 29 is a light-transmitting substrate made of, for example, glass or plastic. On the surface of the counter substrate 29 facing the element substrate 28, the common electrode 22 is formed to face the plurality of pixel electrodes 21. The common 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 encloses an electrophoretic display liquid 80 including positively charged black particles 83, negatively charged white particles 82, and a dispersion medium 81 in which the electrophoretic particles 82 and 83 are dispersed. Yes. In addition, a spacer is provided between the counter substrate 29 and the element substrate 28 for keeping the gap between the substrates at a specified value, and a sealing material for sealing the gap is provided on the end surface of the substrate. This is not shown in the figure.

  In each electrophoretic element 23, when a voltage is applied between the pixel electrode 21 and the common electrode 22 so that the potential of the common electrode 22 is relatively high, the positively charged black particles 83 are coulombs. The white particles 82 that are negatively charged are attracted to the common electrode 22 side by the Coulomb force while being attracted to the pixel electrode 21 side by the force. As a result, the white particles 82 gather on the display surface side (that is, the common electrode 22 side), and the color (that is, white) of the white particles 82 is displayed on the display surface of the display unit 2. Become. Conversely, when a voltage is applied between the pixel electrode 21 and the common 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 common electrode 22 side by Coulomb force. As a result, the black particles 83 gather on the display surface side, and the color of the black particles 83 (that is, black) is displayed on the display surface of the display unit 2.

  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 driving method suitable for the electrophoretic display device 1 configured as described above will be described. In order to simplify the description, the display unit 2 will be described as having a pixel arrangement of 4 pixels P1 to P4 in 2 rows and 2 columns shown in FIG.

  A driving method for normal screen display will be described. Screen display in which scrolling, enlargement / reduction, and page turning are not performed are referred to as normal screen display.

  In normal screen display, a shaking pulse whose voltage polarity is alternately inverted in a short time is applied to all the pixels P1 to P4 of the display unit 2, and then an image writing pulse is repeatedly applied a predetermined number of times. In this way, by applying the shaking pulse prior to the application of the writing pulse, the white particles 82 and the black particles 83 that have been left for a long time to become large lumps can be released (unraveled). Further, high contrast can be realized by repeatedly applying an image writing pulse.

  Driving by the shaking pulse is performed as follows. First, the high potential VH is applied to all the data lines X1 and X2, the low potential VL is applied to the common potential line 11, all the scanning lines Y1 and Y2 are selected for a predetermined time (for example, 10 ms), and all the data lines X1 are selected. , X2 and the common potential line 11 are reversed, and the selection of all the scanning lines Y1, Y2 for a predetermined time again for a predetermined time can be repeated a predetermined number of times (for example, 10 times).

  Driving by the write pulse is performed as follows. As shown in FIG. 4, a case will be described in which only the pixel P1 in the first row and first column is displayed in black, and the other pixels P2 to P4 are displayed in white.

  First, one black display pulse is applied. As shown in FIG. 5A, after the low potential VL is applied to the common electrode line 11 and the data line X2, the high potential VH is applied to the data line X1, the scanning line Y1 is selected for a predetermined time, and the common electrode line 11 This can be realized by applying the low potential VL to the data lines X1 and X2 and selecting the scanning line Y2. The selection time of the scanning line is, for example, around 0.1 msec.

  Next, one white display pulse is applied. As shown in FIG. 5B, a high potential VH is applied to the common electrode line 11 and the data line X1, a low potential VL is applied to the data line X2, and the scanning line Y1 is selected for a predetermined time. This can be realized by applying the high potential VH to the line 11 and the low potential VL to the data lines X1 and X2 and selecting the scanning line Y2 for a predetermined time.

  Such a black display pulse and a white display pulse for each pulse are taken as one set, and this is repeated a predetermined number of times (for example, 30 times), whereby a high contrast display is naturally displayed.

  In the present embodiment, the voltage is applied by a method called “common swing”, but it is naturally possible to use a method in which the common electrode line 11 is the common potential Vcom and a potential difference is relatively provided to the data lines. .

  Next, a case where a screen switching signal is input from the middle of normal screen display will be described. While the screen switching signal is being input, a switching display in which the screen is continuously switched is performed. Here, switching display corresponding to scrolling will be described as an example of the screen operation. However, the same driving method can be applied to image operations such as enlargement / reduction and page turning.

  In normal screen display, as described above, the shaking pulse (if necessary) and the application of the write pulse are repeated a predetermined number of times, but if a screen switching signal is input during the repetition of these pulses, at least the write pulse is the first number. Only the pulse is applied and the current screen is displayed. When the screen switching signal is not input and the switching is completed, the write pulse is applied a predetermined number of times again.

FIG. 6 is a schematic diagram showing the transition of the write pulse in the process of switching from the first screen to the third screen by scrolling the screen. In the first step, the write pulse of the first screen after the start of screen scrolling is shown. In the first screen, the first pixel is displayed in black, the second and third pixels are displayed in white, and only the first pixel is switched from white display to black display from the immediately preceding display screen. In normal screen display, a black display pulse is repeatedly applied to the first pixel a predetermined number of times (for example, 30 times). During the screen scroll period, the first few pulses (two pulses are illustrated in the figure). Apply only. In the second step, the first screen is switched to the second screen, but the first pixel is switched from black display to white display, and the second pixel is switched from white display to black display. Since the screen scroll period is also in the second step, the white display pulse is applied to the first pixel only for the first two times (30 times), and the black display pulse is applied to the second pixel. It is applied only for the first two times within a predetermined number of times (30 times). In the third step, the second screen is switched to the third screen, but the second pixel is switched from black display to white display, and the third pixel is switched from white display to black display. Also, the screen scrolling is stopped. For this reason, the application of the black display pulse is repeated for the third pixel that switches from white display to black display the same number of times (30 times) as normal screen display. Previous screen scrolling for the second pixel being displayed black color in a few pulses (twice) with (the second screen), 2 consisting of a white display pulse and write during the same number of times the black display pulse Apply only pulse to switch from black to white display.

  The display time of each screen (first screen and second screen) displayed during screen scrolling is, for example, about 0.2 seconds to 0.3 seconds. The number of application of the number of write pulses on each screen (first screen and second screen) that is switched during scrolling is reduced to the first few pulses (twice), but naturally with high quality (in other words, high contrast) Display is not possible, but low-contrast display is sufficient if the characters can be recognized when scrolling.

  FIG. 7 is a pulse waveform diagram showing a measurement result of an oscilloscope of voltage waveforms applied to the first pixel and the second pixel when the black display moves. A specific example of the shaking pulse and the write pulse applied to the first pixel and the second pixel in the process of scrolling the screen is shown.

  In the first step, 10 shaking pulses are applied to the first pixel on the first screen, then 2 black display pulses are applied, while 10 shaking pulses are applied to the second pixel, and then the white display pulse is applied. Two pulses are applied. In the second step, after switching to the second screen and applying 10 shaking pulses to the first pixel, applying 2 white display pulses, applying 10 shaking pulses to the second pixel and then displaying black Two pulses are applied. That is, the driving contents corresponding to the first step and the second step schematically shown in FIG. 6 are shown. Although application of the shaking pulse is not essential, an effect of improving the image quality at the time of scrolling in which the number of repetitions of the writing pulse is reduced can be expected.

  According to the inventor's verification, the number of repetitions of the writing pulse at the time of scrolling was the best, but the optimum value is appropriately changed depending on the specification of the display device and the type of application.

  As described above, in the present embodiment, assuming that the screen scroll key is pressed, while the scroll key is pressed and the screen switching signal is being input, the write pulse is only the first few pulses one after another. When the screen is changed and the scroll key is released, the screen change is stopped. After the stop, the write pulse is applied a predetermined number of times, and the fixed display becomes a high-definition display with high contrast.

  In the above description, the entire display unit 2 is the target of rewriting, but the present invention can also cope with partial rewriting in which only a part of the screen is to be rewritten. Hereinafter, a driving method at the time of partial rewriting will be described.

  First, the entire screen is displayed in white. Therefore, the high potential VH is applied to the common electrode line 11 and the low potential VL is applied to the data lines X1 and X2. At this time, the scanning lines Y1 and Y2 may be selected simultaneously or sequentially. Further, a shaking pulse may be applied in advance by the method described in the above embodiment.

  As in the above embodiment, when only the first row and the first column are displayed in black and the others are displayed in white, when a shaking pulse is first required, the shaking pulse is applied only to the first row and the first column. This is realized by repeating only the first row and the first column with white display and further black display for each scan, and further repeating this a predetermined number of times. Further, a black application pulse may be applied a predetermined number of times in the first row and the first column. In this case, since the white display has already been performed, it is not necessary to alternately repeat the black application pulse and the white application pulse, and it is sufficient to apply the black application pulse only to the portion where black display is desired.

  Next, when a screen switching signal is input in the middle of the writing signal, only the first two pulses of the shaking pulse and the black display pulse are fixed and the screen switching signal can be input thereafter, as in the above embodiment. That's fine. By doing so, it is possible to move the screen at a high speed with a low-quality display when changing the screen and a high-quality screen for a fixed display, as in the above embodiment.

DESCRIPTION OF SYMBOLS 1 Electrophoretic display device 2 Display part 3 Data line drive circuit 4 Scan line drive circuit 5 Common electric potential supply circuit 6 Controller 7 User interface part 11 Common electric potential line 20 Pixel 21 Pixel electrode 22 Common electrode 23 Electrophoretic element 24 Transistor for pixel switching 25 Retention capacity 28 Element substrate 29 Counter substrate 81 Dispersion medium 82 White particles 83 Black particles

Claims (5)

A pair of substrates that are arranged to face each other through a space of a predetermined width and at least one of which is light transmissive, a plurality of pixel electrodes formed on a substrate surface of one of the pair of substrates, and the pair of substrates A liquid material obtained by dispersing a common electrode formed on the substrate surface of the other substrate so as to face the plurality of pixel electrodes and two kinds of charged particles having different colors and polarities enclosed between the pair of substrates. And a drive circuit for generating a write pulse for generating a potential difference for moving the charged particles between the pixel electrode and the common electrode,
In the fixed display where the screen does not change, the same image write pulse is repeatedly applied a predetermined number of times at the time of image formation. In the switching display where the screen is continuously switched, the write pulse is applied at the time of image formation on each switching screen. Only the first few pulses are applied to complete the image formation , the screen is continuously switched from the first screen to the second screen and the third screen, and the second screen is a screen immediately before the end of the switching display. And when the switching display ends from the second screen to the third screen, the color display is continuously switched from the first screen to the second screen and the third screen. For the pixel, in the third screen, the display of the color is switched by applying only the number of pulses that is the same number of times as the number of pulses applied in the second screen. Said have for the pixels display is switched to the color from the second screen in the color display the third screen without switching of the first screen, Rukoto applied writing pulse of the same predetermined number of times and the fixed displays An electrophoretic display device.   The electrophoretic display device according to claim 1, wherein the driving circuit applies a shaking pulse whose voltage polarity is alternately inverted in a short time before the writing pulse is applied.   3. The electricity according to claim 2, wherein a shaking pulse is applied to the whole of the plurality of pixels composed of the plurality of pixel electrodes, the common electrode, and the liquid material, and the pixels are sequentially scanned with the address pulse. Electrophoretic display device.   A shaking pulse is applied to a pixel to be rewritten out of a plurality of pixel display units composed of the plurality of pixel electrodes, the common electrode, and the liquid material, and the pixels are sequentially scanned with the writing pulse. The electrophoretic display device according to claim 2. A pair of substrates that are arranged to face each other through a space of a predetermined width and at least one of which is light transmissive, a plurality of pixel electrodes formed on a substrate surface of one of the pair of substrates, and the pair of substrates A liquid material obtained by dispersing a common electrode formed on the substrate surface of the other substrate so as to face the plurality of pixel electrodes and two kinds of charged particles having different colors and polarities enclosed between the pair of substrates. And a driving circuit for generating an address pulse for generating a potential difference for moving the charged particles between the pixel electrode and the common electrode, and a driving method for an electrophoretic display device,
In the fixed display where the screen does not change, the same image writing pulse is repeatedly applied a predetermined number of times during image formation, and in the switching display where the screen is switched continuously, the first few pulses of the writing pulse during image formation on each switching screen Image formation is completed by applying only the first screen, the screen is continuously switched from the first screen to the second screen, and the third screen, and the second screen is a screen immediately before the end of the switching display, the second screen When the display is switched from the screen to the third screen and the switching display is finished, the third display is performed for the pixels that continuously switch the color display from the first screen to the second screen and the third screen. On the screen, the display of the color is switched by applying only the number of pulses that is the same number of times as the number of pulses applied on the second screen. Wherein for pixels to switch the display of the color from a second screen, the fixed display and the electrophoretic display device comprising that you apply a write pulse of the same predetermined number of times in the color display the third screen without switching of the Driving method.

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