JP2011227147A - Driving method of electronic portal imaging device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a driving method for minimizing an occurrence of contour afterimages in partially driving a part of display area of an electronic portal imaging device.SOLUTION: A driving method of an electronic portal imaging device to display pattern images on an electronic portal imaging unit consisting of a plurality of display pixels by electrophoresis arranged in a matrix state comprises: a step of dividing a display pattern to be displayed on the electronic portal imaging unit into a plurality of patterns and storing the patterns as a plurality of divided pattern data in advance; a step of supplying the plurality of divided pattern data to the electronic portal imaging unit in a time-sharing manner and displaying the whole of display pattern; and a step of supplying data on the display pattern to the electronic portal imaging unit and deleting the whole of display pattern displayed.

Description

  The present invention relates to a driving method for driving an electrophoretic display device (EPD), and more particularly to a driving method capable of reducing an afterimage when an image is erased.

  Electrophoretic display devices are attracting attention as substitutes for paper media. In the electrophoretic display device, a microcapsule filled with colored charged particles and a dispersion medium is disposed between two electrodes, and a bias voltage is applied to the charged particles to move the transparent electrode side (visible position), thereby moving the pixel. Display is in progress. The electrophoretic display device consumes electric power to move the electrophoretic particles when updating display information, but does not require electric power after the display is updated once, and thus has low power consumption. For this reason, for example, it is suitable for the display of a battery-powered timepiece that requires low power consumption and long-time operation. For example, JP 2007-206267 A and JP 2008-242383 A describe examples of electrophoretic display devices.

JP 2007-206267 A JP 2008-242383 A

  A battery-powered watch is desired to have a long battery replacement interval. For this reason, various devices for reducing power consumption have been applied to timepiece electrophoretic display devices. For example, an electrophoretic display device consumes power when updating an image display (deleting display + writing data). Therefore, the entire display screen or a range of a display area is not erased together with the background and the display pattern. The number of pixels to be rewritten is reduced by writing inverted data of the same pattern on the display pattern and erasing it. When such partial driving is performed, an afterimage of the contour of the original display pattern may occur. Therefore, erasing with an opposite color pattern that is slightly larger than the original pattern, or erasing with an opposite color pattern with only an outline with an appropriate pixel width on the outline afterimage, erases the outline afterimage. New data can be written.

  However, although the contour afterimage disappears, the writing energy (pulse voltage × time) and the erasing energy (pulse voltage × time) cannot be balanced (so-called DC balance). The DC balance is the sum of the electric field energy of one polarity for black display and the electric field energy of the other polarity for white display over the entire display sheet of the electrophoretic display device (the strength of the electric field × the sum of the application time). Is the balance. When this DC balance is lost, a kind of electrochemical reaction occurs in the electrophoretic display sheet, causing irreversible damage such as electrode coloring and display burn-in, greatly affecting product reliability. give.

  Accordingly, an object of the present invention is to provide a driving method in which only a part of the display area of an electrophoretic display device is driven and an outline afterimage is not generated as much as possible.

  Another object of the present invention is to provide a method for driving an electrophoretic display device that does not disturb the DC balance as much as possible.

  One embodiment of the present invention that achieves the above object is a method of driving an electrophoretic display device that displays a pattern image on an electrophoretic display device in which a plurality of display pixels by electrophoresis are arranged in a matrix. A step of dividing a display pattern to be displayed on the electrophoretic display into a plurality of patterns and storing it as a plurality of divided pattern data, and supplying the plurality of divided pattern data to the electrophoretic display in a time-sharing manner. And displaying the entire display pattern, and supplying the display pattern data to the electrophoretic display and erasing the displayed display pattern.

  By adopting such a configuration, the strength of the oblique electric field generated during display is reduced to prevent the charged particles from sticking to the microcapsule wall. Further, at the time of erasing, the generation of the afterimage is prevented by peeling the charged particles from the wall with an oblique electric field relatively stronger than the display. The division pattern data may not be stored in advance, but may be divided from the display pattern to be displayed every time it is displayed or deleted, but it is substantially the same although there is a temporal difference from the present invention. It is considered an invention.

  The plurality of divided pattern data is preferably divided into at least contour pattern data and non-contour pattern data of a pattern to be displayed. Thereby, the oblique electric field can be weakened along the contour of the pattern.

  It is desirable to display the contour pattern data after displaying the non-contour pattern data. As a result, the image is displayed visually without a sense of incongruity.

  The display of the pattern data of the non-contour part is performed with a display energy relatively stronger than the display of the pattern data of the contour part (or the display of the pattern data of the contour part is more than the display of the pattern data of the non-contour part. It is desirable to be done with weak display energy). Thereby, the intensity | strength of the diagonal electric field of an outline part can be lowered | hung.

  In the erasing step, it is desirable to erase the entire displayed display pattern at the same time. Thereby, the intensity of the oblique electric field at the time of erasing can be made larger than the oblique electric field at the time of display.

  The erasing step includes a step of erasing a contour pattern of the displayed display pattern and a step of erasing a non-contour portion pattern, and the erasing of the contour portion pattern is performed more than the non-contour portion pattern. It is desirable to be performed with strong energy. As a result, the oblique electric field at the contour of the pattern becomes stronger at the time of erasing, and the afterimage is less likely to remain (facilitation of peeling from the wall of the antistatic particles attached to the wall of the microcapsule is promoted).

  The energy for display or erasure is represented by the product of the drive voltage applied to the pixel electrode of the electrophoretic display and the drive time. Furthermore, it is desirable that the display energy and the erasing energy are obtained as cumulative values over the entire area of the display, and are set so that these values are balanced as much as possible.

  The energy for display or erasing can be obtained as the width of the pulse voltage, the level of the pulse voltage, and the number of pulses.

  According to the driving method of the electrophoretic display device of the present invention, it is possible to obtain a driving method in which a contour afterimage is not generated as much as possible in partial driving. Further, it is possible to obtain a method for driving an electrophoretic display device that does not disturb the DC balance as much as possible.

It is explanatory drawing explaining generation | occurrence | production of the outline afterimage in the partial rewriting. It is explanatory drawing explaining the diagonal electric field which causes a contour afterimage. It is explanatory drawing explaining rewriting the pattern division | segmentation of a display base image. It is a block diagram explaining the timepiece device which uses an electrophoretic display device for a display. 3 is a block diagram illustrating an example of an electrophoretic display device 6. FIG. 2 is an explanatory diagram illustrating a configuration of a pixel circuit 20. FIG. 3 is an explanatory diagram illustrating functions of a pixel circuit 20. FIG. It is explanatory drawing explaining the example of a display of an image. FIG. 3 is a signal timing diagram illustrating Example 1; FIG. 6 is a signal timing diagram illustrating Example 2; FIG. 6 is a signal timing diagram illustrating Example 3.

Embodiments of the present invention will be described below with reference to the drawings.
First, an afterimage in partial driving of an electrophoretic display device will be described with reference to FIG. As shown in A of the figure, pixel data “0” corresponding to white display is written in all the pixels of the image memory of the display device, and the display device is driven by this image data so that the display device is in a colorless display state. (Erase state).

  Next, as shown in FIG. 1B, partial rewriting for displaying, for example, the pattern “0” is performed in the colorless area. Partial rewrite is performed with the data of each pixel constituting the pattern “0” portion of the area of the image memory set to “1” and the data of each pixel constituting the non-pattern portion as data “0”. Each pixel driven by data “1” forms a pattern “0” on the screen.

  Next, as shown in FIG. 1C, “0” is erased in order to rewrite the pattern. This erasing is performed by driving the display device with image data obtained by inverting the data “1” of each pixel constituting the pattern “0” portion. At this time, an afterimage is generated at the contour of the pattern “0” as shown in FIG.

  Next, as shown in FIG. 1D, the data “1” is written in each pixel corresponding to the pattern “1” of the image memory, and the pattern “1” is displayed in the area where the previous pattern “0” is displayed. . As a result, as shown in FIG. 1D, the display having the afterimage of the outline of the pattern “0” exists during the display of the pattern “1”.

  As described above, if the image is rewritten with an erase pattern larger than the write pattern, the afterimage can be erased. However, as a result of the erase energy becoming larger than the write energy, the DC balance cannot be achieved. .

FIG. 2 is an explanatory diagram for explaining the reason why a contour afterimage occurs. The reason why the contour afterimage is generated is not exactly clarified, but can be roughly explained as follows.
First, as shown in FIG. 2A, in the case of partial rewriting drive, electric lines of force from the pixel electrode side to the common electrode are generated. The electric lines of force are straight and parallel at the center of the pixel electrode, but spread obliquely on the outer peripheral side of the end of the pixel electrode. The electric field (oblique electric field) where the electric lines of force are oblique moves the charged particles in the microcapsules (not shown) in an oblique direction. The charged particles move toward the side wall of the microcapsule and stick to the side wall.

  Next, when partial erasure driving is performed, as shown in FIG. 2B, lines of electric force are generated in the opposite direction from the common electrode side toward the pixel electrode. Of these, the oblique electric field acts to peel off the charged particles attached to the side wall of the microcapsule, but the electric field on the outer peripheral side of the end of the pixel electrode is weak. In order to peel off the charged particles once stuck to the side wall of the microcapsule, a larger electric field is required, and the charged particles remain on the wall surface. This is considered to be a contour afterimage.

  Therefore, the present invention makes the oblique electric field at the time of partial rewriting drive relatively weaker than the oblique electric field at the time of erasing to weaken the sticking to the side wall of the charged particles and prevent the generation of the afterimage. Further, by making the oblique electric field at the time of partial erasure driving relatively stronger than the oblique electric field at the time of partial rewriting, the charged particles stuck to the side wall are peeled off to prevent the occurrence of the afterimage.

FIG. 3 is a diagram for explaining a method of weakening the oblique electric field at the time of partial rewriting driving.
Various methods for weakening the oblique electric field at the time of partial rewriting were examined, and it was found that the oblique electric field was weakened when the pattern area or pattern width was reduced.

  As shown in FIG. 3A, for example, when the pattern “0” of the display base image is displayed, this pattern is divided into a plurality of patterns in the inner and outer directions (or the direction perpendicular to the tangent to the pattern contour), and the pattern width It is divided into a plurality of narrow division patterns. In the example shown in the figure, the base pattern “0” is divided into divided patterns of a divided image A on the inner peripheral side, a divided image C on the central portion, and a divided image B on the outer peripheral side. In addition, when the divided image AB including the divided image A and the divided image B is used, the oblique electric field of each divided image is weaker than that of the base image.

  In this way, partial writing is performed by sequentially writing with a plurality of divided patterns A, B, and C (with a weak oblique electric field), and a strong base electric field is displayed with a display base image pattern (pattern A + B + C) of a base image that is not divided. In this case, the afterimage is prevented from being generated by performing partial erasure driving. The order of pattern writing is not so important, but it is natural and preferable that the order of the center pattern C, the one end pattern A (or B), and the other end pattern B (or A) is seen. Further, the order of the center pattern C and the both end patterns AB may be used.

According to the above-described method, the DC balance is maintained because the area of the partially rewritten write pattern is equal to the area of the partially erased pattern.
Further, in order to weaken the oblique electric fields of the patterns A and B, the driving of the patterns A and B may be weaker than the driving of the central pattern C. As will be described later, the pulse width of the drive pulse may be shortened. A method of reducing the number of drive pulses or lowering the drive voltage may be used.
Partial erasure may also be performed in a divided pattern. As will be described later, for example, when performing partial erasure with the center pattern C and the both end patterns AB, the width, number, voltage level, etc. of the erase drive pulses of the both end patterns AB are larger than the drive pulses for writing. By doing so, the afterimage removal effect can be enhanced.

  It is desirable to set the partial rewriting drive energy and the partial erasing energy so as to balance as much as possible. However, even if there is some imbalance, it does not cause a problem due to DC imbalance.

Example 1
4 to 8 are diagrams for explaining the first embodiment of the present invention.
FIG. 4 shows an example of a timepiece device using the method for driving an electrophoretic display device of the present invention. The clock device includes an input unit 2 composed of switches and the like (not shown) for setting time display, a clock computer 4 for outputting display data such as time and calendar to a display, and an electrophoretic display for displaying the display data as a visible image. It is comprised by the apparatus 6 grade | etc.,. These devices can be constructed from known devices.

  The clock computer 4 includes a CPU, a RAM, a ROM, an input / output interface, and the like (not shown). In the ROM, in addition to a control program for each unit, a clock program for displaying the date and time, a program for displaying a calendar, and the like, which are executed by the CPU, the division pattern of each display pattern described above is stored in advance.

  FIG. 5 shows a configuration example of the electrophoretic display device 6. For example, those described in JP 2007-206267 A and JP 2008-242383 A described above can be used, but the invention is not limited thereto.

  The electrophoretic display device is an active matrix display, and includes pixel circuits 20 arranged in a matrix on a substrate 10. That is, each pixel circuit 20 includes a plurality of data lines X extending along the column direction (vertical direction in FIG. 1) and a plurality of scans extending along the row direction (horizontal direction in FIG. 5). A line (gate line) Y is arranged at each intersection. Each pixel circuit 20 includes a data set unit 21 including a switching element, a pixel memory, a transfer gate, and the like, which will be described later, and a pixel electrode P. A power set line VEP extending in the column direction is connected to the data set unit 21 of each pixel circuit 20. Each scanning line Y is connected to the scanning line driving circuit 11, each data line X is connected to the data line driving circuit 12, and each power supply line VEP is connected to the power supply line control circuit 13. Note that the common electrode COM formed on the counter substrate 30 described later is connected to the common electrode control circuit 14 via the wiring C displayed on the bus. The wiring C represents a plurality of wirings (Vcom, VPIX, S1, S2 described later) for the convenience of drawing.

  The controller 15 that controls the scanning line driving circuit 11, the data line driving circuit 12, the power supply line control circuit 13, and the common electrode control circuit 14 includes an image signal processing circuit and a timing generator. Here, the image signal processing circuit receives a display data signal and various control signals from the clock computer 4 and generates image data, a power supply line control signal, and a common electrode control signal. Output to the line control circuit 13 and the common electrode control circuit 14. The image signal processing circuit generates reset data and outputs the reset data to the data line driving circuit 12, the power supply line control circuit 13, and the common electrode control circuit 14. The timing generator generates various timing signals for controlling the scanning line driving circuit 11 and the data line driving circuit 12 when image data, reset data, and the like are output from the image signal processing circuit.

  Based on various timing signals from the controller 15, the scanning line driving circuit 11 outputs a scanning signal for sequentially selecting the scanning lines Y at a predetermined timing to each scanning line.

  The data line driving circuit 12 generates a data signal to be supplied to each data line X based on the image data and reset data from the controller 15. Further, the data line driving circuit 12 outputs the generated data signal based on the timing signal from the controller 15 to the group of pixel circuits 20 connected to the scanning line Y selected by the scanning line driving circuit 11. .

  The power supply line control circuit 13 supplies a power supply potential having a predetermined voltage value to each pixel circuit 20 through the power supply lines VEP and VPIX based on a power supply line control signal from the controller 15. Based on a command signal from the controller 15, the power supply line control circuit 13 uses the high voltage HV (for example, 15 [V]) and the low voltage LV (for example, 5 [V]) as the power supply voltage VEP to each pixel circuit 20. To supply.

  Based on the common electrode control signal from the controller 15, the common electrode control circuit 14 supplies an inverted drive signal to the common electrode COM through the bus-like wiring (bundle of a plurality of lines) C. The common electrode control circuit 14 supplies an erasing high voltage HV (for example, 15 [V]) to the common electrode COM through the wiring C based on the reset data from the controller 15. Further, the common electrode control circuit 14 sets the potentials of the drive signal lines S1 and S2 of the bus wiring C (for example, 15 [V], 0 [V]) based on a command signal from the controller 15.

  FIG. 6 is a circuit diagram showing an internal configuration of each pixel circuit 20 of the electrophoretic display device. As shown in the figure, each pixel circuit 20 is connected in parallel by a switching NMOS transistor Q1, a latch (pixel memory) M composed of two CMOS inverters, and P-type and N-type transistors. Two transfer gates and a pixel electrode P are provided. The outputs of the pixel memory M are applied to the gates of the two transfer gates operating in a complementary manner, signals S1 and S2 are supplied to the respective one ends of the two transfer gates, and the other ends are both applied to the pixel electrode P. It is connected.

  In this electrophoretic display device, first, image data is written into the pixel memory M at a low voltage. Thereafter, during a series of drawing sequences such as all black, all white erasing, reverse erasing, and normal images, drawing can be performed by combining the signals S1 and S2 with H and L without rewriting image data.

  FIG. 7 is a diagram simply representing the function of the pixel circuit 20. The conduction values of the two transfer gates are complementarily controlled by the holding values (H, L) of the memory M, and the signal voltage S1 or S2 relayed to the pixel electrode is selected.

  FIG. 8 is a diagram illustrating the output (H, L) of the signal voltages S1 and S2, the signal state of the display pixel circuit, and the display image state. As shown in the figure, when all the images are displayed in black, the output of the signal voltages S1 and S2 is set to the H level (for example, 15 [V]), so that the display is performed regardless of the value held in the memory M. The pixels of the vessel can be displayed black. When all the images are displayed in white, the output of the signal voltages S1 and S2 are both set to L level (for example, 0 [V]), so that the pixels of the display are displayed in white regardless of the value held in the memory M. can do.

  When an image (pixel) held in the memory M is displayed as a normal image, the signal S1 is set to the H level and the signal S2 is set to the L bell so that the image corresponding to the held value in the memory M (the normal image) is displayed. ) Is displayed on the display.

  When displaying the image (pixel) stored in the memory M as an inverted image, the signal S1 is set to L level and the signal S2 is set to H bell, so that the image (normal image) held in the memory M and the black and white are displayed. An image with reversed colors (or colors) is displayed on the display.

  FIG. 9 is a signal timing diagram illustrating a rewrite operation and an erase operation in the first embodiment. Each signal line is initially electrically disconnected from the pixel circuit (high impedance; HiZ). In the first embodiment, as shown in FIG. 3, the display base image is divided into a plurality of patterns at the time of partial rewriting driving to suppress the generation of the afterimage, and the contour afterimage generated by the oblique electric field generates a stronger oblique electric field. Delete the entire pattern of the display base image.

As shown in FIG. 9, the memory M of the pixel circuit 20 can operate when the power supply VEP is changed from HiZ to 5 [V].
When the clock computer 4 outputs the display data of the central pattern C to the controller 15 in the partial drive rewriting operation mode, the controller 15 divides the pixel data and transfers it to the corresponding pixel memory M.

  Next, the controller 15 performs rewriting driving of the central pattern C. The controller 15 raises the power supply VEP to 15 [V], raises the threshold value for writing to the memory M, and fixes the output of the memory M. The common electrode voltage VCOM is set to 0 [V] to enable writing. During the writing period, the signal S1 is set to the 0 [V] state, and the signal S2 is changed to the L level (0 [V]) and the H level (15 [V]), thereby forming a plurality of drive pulses to form the pixel electrode P. To supply. Thereby, the pattern of the divided image C is displayed on the display. Note that since the inverted value of the input data is held in the memory M using the inverter, the “inverted” mode is selected as the combination of the signals S1 and S2. Thereafter, the power supply VEP is set to 5 [V], and the other signal lines are set to the electrical cutoff state HiZ.

  Similarly, when the timepiece computer 4 outputs the display data of the divided image pattern AB to the controller 15, the controller 15 divides it into pixel data and transfers it to each corresponding pixel memory M. The controller 15 rewrites the pattern AB. The controller 15 raises the power supply VEP to 15 [V], raises the threshold value for writing to the memory M, and fixes the output of the memory M. The common electrode voltage VCOM is set to 0 [V] to enable writing. During the writing period, the signal S1 is set to the 0 [V] state, and the signal S2 is changed to the L level (0 [V]) and the H level (15 [V]), thereby forming a plurality of drive pulses to form the pixel electrode P. To supply. Thereby, the pattern of the divided image AB is displayed on the display. Thereafter, the power supply VEP is set to 5 [V], and the other signal lines are set to the electrical cutoff state HiZ.

  In this way, the center pattern C and the end pattern AB are written, and the entire display base image is displayed.

  Next, the erase operation by partial drive will be described. When the clock computer 4 outputs the display data of the display base image pattern to the controller 15, the controller 15 divides it into pixel data and transfers it to each corresponding pixel memory M. The controller 15 performs erasure driving of the base image pattern. The controller 15 raises the power supply VEP to 15 [V], raises the threshold value for writing to the memory M, and fixes the output of the memory M. The common electrode voltage VCOM is set to 15 [V], and the electric field direction is reversed to enable erasure writing. During the erasing period, the signal S1 is set to the 15 [V] state, and the signal S2 is changed to the L level (0 [V]) and the H level (15 [V]), thereby forming a plurality of drive pulses to the pixel electrode P. Supply. Accordingly, the display base image is driven to display the reverse pattern of the display base image on the display, and the displayed display base image disappears. Thereafter, the power supply VEP is set to 5 [V], and the other signal lines are set to the electrical cutoff state HiZ.

  In this way, the central portion pattern C and the end portion patterns AB divided into regions at the time of rewriting are written in a time division manner, and the entire display base image is displayed. Thereafter, the image displayed at the time of erasing is erased at once for the entire display base image. The outline afterimage generated by the weak oblique electric field is removed by being erased by the strong oblique electric field.

(Example 2)
FIG. 10 is a signal timing diagram illustrating the rewrite operation according to the second embodiment. In this embodiment, the rewriting driving and erasing driving of the central pattern are the same as those in the first embodiment, and the description thereof is omitted.

  In this embodiment, the pulse width of the signal S2 is made narrower than in the case of Example 1 when the both-end pattern AB is rewritten. The width of the drive pulse of the both end pattern AB is reduced to be smaller than the pulse width of the central pattern C to weaken the oblique electric field, thereby preventing the occurrence of the afterimage. Further, the same effect can be obtained even if the number of driving pulses and the pulse voltage of the both end pattern AB are lowered from those of the central pattern C.

(Example 3)
FIG. 11 is a signal timing chart for explaining the erase operation in the third embodiment. In this embodiment, the rewriting drive of the center pattern and the both end patterns AB is the same as that in the first or second embodiment, and thus the description thereof is omitted.

  In the third embodiment, the rewrite drive is performed in the same manner as in the first embodiment, but the depolarization drive is not performed on the display base image at a time, but is erased in a time-sharing manner with the divided pattern C and the divided pattern AB. . At this time, the width of the depolarization drive pulse of the pattern AB is made larger than the width of the erase drive pulse of the pattern C. As a result, the oblique electric field for erasure is increased to prevent the generation of the afterimage.

  As described above, in the embodiment of the present invention, the display image to be partially rewritten is previously divided into a plurality of patterns such as the one end pattern, the center pattern, and the other end pattern. The image (multiple images) is divided into multiple times and rewritten in a time-sharing manner. Although the order of rewriting is not particularly limited, for example, the order of the center pattern, the one end pattern, and the other end pattern is preferable in appearance. Further, the order of the center pattern and the both end patterns may be used. In partial erasure driving, an oblique electric field is stronger than in rewriting driving by driving with an image that is not divided, and an afterimage is less likely to remain.

  Further, the rewriting drive of the one end portion and the other end pattern may be less energy than the rewriting drive of the central portion pattern. For this purpose, methods such as shortening the pulse width of the drive pulse, reducing the number of pulses, and lowering the drive voltage can be taken. Further, in the case of divided erasure driving as in the partial rewriting driving, the afterimage is less likely to remain by driving the one end pattern and the other end pattern stronger than the central pattern.

Although it is important to minimize the disruption of DC balance, DC unbalance that does not affect performance is acceptable.
In the present invention, the pixel circuit is not limited to the 9-transistor type described above. Various types such as a one-transistor one-capacitor pixel circuit can be used.

  According to the present invention, by performing division driving at the time of rewriting, the generation of a contour afterimage can be suppressed, and the contour afterimage generated by the oblique electric field can be removed only by the oblique electric field. Accordingly, it is possible to avoid DC imbalance caused by driving a pixel portion that is not originally driven by an expanded image or an edge image, which is preferable as a countermeasure against a contour afterimage.

2 input unit, 4 clock computer, 6 electrophoretic display device, 10 substrate, 11 scanning line driving circuit, 12 data line driving circuit, 13 power line driving circuit, 14 common electrode driving circuit, 15 controller, 20 pixel circuit, M Memory, T transfer gate, P pixel electrode

Claims (7)

An electrophoretic display device driving method for displaying a pattern image on an electrophoretic display device in which a plurality of display pixels by electrophoresis are arranged in a matrix,
Dividing a display pattern to be displayed on the electrophoretic display in advance into a plurality of patterns and storing them as a plurality of divided pattern data;
Supplying the plurality of divided pattern data to the electrophoretic display in a time-sharing manner to display the entire display pattern;
Supplying the display pattern data to the electrophoretic display and erasing the entire displayed display pattern;
A method for driving an electrophoretic display device comprising:   2. The driving method of an electrophoretic display device according to claim 1, wherein the plurality of divided pattern data are divided into at least contour pattern data and non-contour pattern data of a pattern to be displayed.   The driving method of the electrophoretic display device according to claim 2, wherein the pattern data of the contour portion is displayed after the pattern data of the non-contour portion is displayed.   The method for driving an electrophoretic display device according to claim 2, wherein the display of the pattern data of the contour portion is performed with a display energy weaker than the display of the pattern data of the non-contour portion.   The method of driving an electrophoretic display device according to claim 1, wherein the erasing step simultaneously erases the entire displayed display pattern. The erasing step includes a step of erasing the pattern of the contour portion of the displayed display pattern and a step of erasing the pattern of the non-contour portion,
4. The method for driving an electrophoretic display device according to claim 2, wherein the erasing of the contour pattern is performed with a stronger energy than the non-contour pattern.   The method for driving an electrophoretic display device according to claim 4, wherein the energy for display or erasure is represented by a product of a driving voltage applied to a pixel electrode of an electrophoretic display and a driving time.