JP6811052B2 - Drive, drive method, and display - Google Patents

Description

The present disclosure relates to a drive device and a drive method for driving a display device using an electrophoretic display element, and a display device including such a drive device.

For example, electronic paper often uses a bistable electro-optical display using an electrophoretic display element. For example, Patent Documents 1 and 2 disclose a method of driving an electro-optical display.

Japanese Unexamined Patent Publication No. 2012-177944 Japanese Unexamined Patent Publication No. 2016-855477

By the way, in general, it is desired that the display device has high image quality, and the electro-optical display using the electrophoresis display element is also expected to improve the image quality.

It is desirable to provide a drive device, a drive method, and a display device capable of improving the image quality.

The drive device according to the embodiment of the present disclosure includes a drive unit. The drive unit maintains a display state belonging to the first peripheral region outside the pixel region in which a color other than a predetermined color is rewritten to a predetermined color among a plurality of pixels each having an electrophoresis element and a pixel electrode. The first pixel is driven so that the first pulse signal is generated in the pixel electrode of one pixel, and the display state belonging to the second peripheral region outside the first peripheral region is maintained. The second pixel is driven so that the second pulse signal is generated in the pixel electrode of the above. The drive time in the first pulse signal overlaps with the drive time in the second pulse signal, and the drive time in the second pulse signal is shorter than the drive time in the first pulse signal. The first pulse signal includes a first voltage corresponding to a predetermined color and a second voltage. The second pulse signal includes a third voltage and a second voltage. The drive time of the third voltage in the second pulse signal is shorter than the drive time of the first voltage in the first pulse signal.

In the driving method according to the embodiment of the present disclosure, among a plurality of pixels each having an electrophoretic element and a pixel electrode, a first peripheral region outside a pixel region for rewriting a color other than a predetermined color to a predetermined color first pulse signal to the pixel electrode of the first pixel display state is maintained drives the first pixel to produce belongs, the display state belonging to the second peripheral area outside the first peripheral area The second pixel is driven so that the second pulse signal is generated in the pixel electrode of the second pixel to be maintained . The drive time in the first pulse signal overlaps with the drive time in the second pulse signal, and the drive time in the second pulse signal is shorter than the drive time in the first pulse signal. The first pulse signal includes a first voltage corresponding to a predetermined color and a second voltage. The second pulse signal includes a third voltage and a second voltage. The drive time of the third voltage in the second pulse signal is shorter than the drive time of the first voltage in the first pulse signal.

The display device according to the embodiment of the present disclosure includes a display unit and a drive unit. The display unit has a plurality of pixels, each of which has an electrophoresis element and a pixel electrode. Drive unit, among the plurality of pixels, a first pulse to a pixel electrode of the first pixel display state belonging to the first peripheral region outside the pixel region to be rewritten from the color other than the predetermined color to a predetermined color is maintained A second pulse signal is generated at the pixel electrode of the second pixel, which drives the first pixel so as to generate a signal and maintains the display state belonging to the second peripheral region outside the first peripheral region. As described above, the second pixel is driven. The drive time in the first pulse signal overlaps with the drive time in the second pulse signal, and the drive time in the second pulse signal is shorter than the drive time in the first pulse signal. The first pulse signal includes a first voltage corresponding to a predetermined color and a second voltage. The second pulse signal includes a third voltage and a second voltage. The drive time of the third voltage in the second pulse signal is shorter than the drive time of the first voltage in the first pulse signal.

In the drive device, drive method, and display device according to the embodiment of the present disclosure, the pixel area is rewritten from a color other than the predetermined color to a predetermined color. Then, the first pixel belonging to the first peripheral region outside the pixel region is driven so that the first pulse signal is generated in the pixel electrode of the first pixel. Then, the second pixel belonging to the second peripheral region outside the first peripheral region is driven so that the second pulse signal is generated in the pixel electrode of the second pixel.

According to the drive device, drive method, and display device according to the embodiment of the present disclosure, the first pixel is set so that the first pulse signal is generated at the pixel electrode of the first pixel belonging to the first peripheral region. Since the second pixel is driven so that the second pulse signal is generated at the pixel electrode of the second pixel belonging to the second peripheral region, the image quality can be improved. The effects described here are not necessarily limited, and any of the effects described in the present disclosure may be used.

It is a block diagram which shows one configuration example of the display device which concerns on embodiment of this disclosure. It is explanatory drawing which shows one operation example of the display part shown in FIG. It is explanatory drawing which shows the other operation example of the display part shown in FIG. It is explanatory drawing which shows one operation example of the drive part shown in FIG. It is another explanatory diagram which shows one operation example of the drive part shown in FIG. It is a timing waveform diagram which shows one operation example of the display device shown in FIG. It is a timing waveform diagram which shows the other operation example of the display device shown in FIG. It is explanatory drawing which shows one operation example of the display device which concerns on a reference example. It is explanatory drawing which shows one operation example of the display device which concerns on a reference example. It is another explanatory diagram which shows one operation example of the display device which concerns on a reference example. It is explanatory drawing which shows one operation example of the display device which concerns on other reference examples. It is explanatory drawing which shows one operation example of the display device which concerns on other reference examples. It is another explanatory diagram which shows one operation example of the display device which concerns on other reference examples. It is explanatory drawing which shows one operation example of the display device shown in FIG. It is explanatory drawing which shows one operation example of the display device shown in FIG. It is another explanatory diagram which shows one operation example of the display device shown in FIG. It is a timing waveform diagram which shows one operation example of the display device shown in FIG. It is a timing waveform diagram which shows the other operation example of the display device shown in FIG. It is a flowchart which shows one operation example of the display device shown in FIG. It is another flowchart which shows one operation example of the display device shown in FIG. It is a timing waveform diagram which shows one operation example of the display device which concerns on a modification. It is a timing waveform diagram which shows one operation example of the display device which concerns on another modification. It is a timing waveform diagram which shows one operation example of the display device which concerns on another modification. It is a timing waveform diagram which shows one operation example of the display device which concerns on another modification. It is explanatory drawing which shows one operation example of the display device which concerns on another modification. It is explanatory drawing which shows one operation example of the display device which concerns on another modification. It is another explanatory diagram which shows one operation example of the display device which concerns on another modification. It is a timing waveform diagram which shows one operation example of the display device which concerns on another modification. It is a perspective view which shows an example of the appearance of application example 1. FIG. It is a perspective view which shows another example of the appearance of application example 1. FIG. It is a perspective view which shows the appearance of application example 2. FIG. It is a perspective view which shows an example of the appearance of application example 3. FIG. It is a perspective view which shows another example of the appearance of application example 3. FIG.

Hereinafter, embodiments of the present disclosure will be described in detail with reference to the drawings. The explanation will be given in the following order.
1. 1. Embodiment 2. Application example

<1. Embodiment>
[Configuration example]
FIG. 1 shows a configuration example of a display device (display device 1) according to an embodiment. The display device 1 is a bistable electro-optical display using an electrophoresis display element. Since the drive device and the drive method according to the embodiment of the present disclosure are embodied by the present embodiment, they will be described together. The display device 1 includes a display unit 20 and a drive unit 10.

The display unit 20 has a plurality of pixels 9 arranged in a matrix. Further, the display unit 20 has a plurality of (N lines in this example) scanning lines SCL (scanning lines SCL (1) to SCL (N)) extending in the horizontal direction (horizontal direction in FIG. 1) and a vertical direction (FIG. 1). It has a plurality of signal lines SGL extending in the vertical direction in 1). One end of the plurality of scanning lines SCL and one end of the plurality of signal lines SGL are connected to the drive unit 10, respectively.

Pixel P has a transistor 21 and a display element 22. The transistor 21 is an N-type MOS (Metal Oxide Semiconductor) transistor in this example. The source of the transistor 21 is connected to the signal line SGL, the gate is connected to the scanning line SCL, and the drain is connected to the display element 22. In this example, the display element 22 is configured to include a microcapsule type electrophoresis element, one end of which is connected to the drain of the transistor 21 and the other end of which is supplied with a voltage Vcom (for example, 0V). There is.

2A and 2B schematically show a configuration example of the display unit 20, FIG. 2A shows a case where the pixel P displays white, and FIG. 2B shows a case where the pixel P displays black. The display unit 20 includes a drive substrate 30, an opposed substrate 40, and a plurality of microcapsules 23.

The drive board 30 is arranged on the side of the display unit 20 opposite to the display surface side. The drive substrate 30 has a substrate 31 and a plurality of pixel electrodes 32. Although not shown, the substrate 31 is formed with a transistor 21, a scanning line SCL, and a signal line SGL. The plurality of pixel electrodes 32 are formed on the surface of the substrate 31 at a ratio of one to each pixel P. The pixel electrode 32 is made of, for example, a metal material such as gold (Au), silver (Ag), copper (Cu), or aluminum (Al). The pixel electrode 32 is connected to the drain of the transistor 21. A voltage is supplied to the pixel electrode 32 by the signal line driving unit 15.

The facing substrate 40 is arranged on the display surface side of the display unit 20 so as to face the drive substrate 30. The facing substrate 40 has a substrate 41 and a facing electrode 42. The substrate 41 has light transmittance. The counter electrode 42 is uniformly formed on the surface of the substrate 41 over a region corresponding to a plurality of pixels P. The counter electrode 42 has a light transmissive property, and is constructed by using a light transmissive conductive material such as ITO (Indium Tin Oxide). A voltage Vcom (for example, 0V) is supplied to the counter electrode 42 by the drive unit 10.

The microcapsule 23 corresponds to the display element 22 and has a spherical shape. The microcapsules 23 are arranged between the drive substrate 30 and the facing substrate 40 at a ratio of, for example, a plurality (for example, about 4) to each pixel P, and are fixed by a binder 26. In FIGS. 2A and 2B, the microcapsules 23 are drawn at a ratio of one to each pixel P for convenience of explanation. The microcapsules 23 contain a plurality of electrophoretic particles 24W and a plurality of electrophoretic particles 24B, and are filled with a dispersion medium 25. The running particles 24W are responsible for whitening, and have, for example, a positive charge. The electrophoretic particle 24B is responsible for displaying black, and has, for example, a negative charge. The dispersion medium 25 disperses a plurality of migration particles 24W and 24B in the microcapsules 23.

With this configuration, in each pixel P, an electric field is generated according to the voltage of the pixel electrode 32 (pixel voltage Vpix), and the electrophoretic particles 24W and 24B in the microcapsules 23 move in the dispersion medium 25 according to the electric field. To do.

Specifically, for example, when the pixel voltage Vpix is set to a positive voltage Vp (for example, + 15V), since the traveling particles 24W have a positive charge, the inside of the microcapsule 23 is directed toward the counter electrode 42. Since the traveling particles 24B have a negative charge, they move in the microcapsules 23 toward the pixel electrode 32. Therefore, for example, when the pixel voltage Vpix is set to the voltage Vp for a long time, as shown in FIG. 2A, the electrophoretic particles 24W responsible for the white display gather on the display surface S side, so that the pixel P displays the white display. Do.

Further, for example, when the pixel voltage Vpix is set to a negative voltage Vm (for example, -15V), the traveling particles 24B have a negative charge and therefore move in the microcapsule 23 toward the counter electrode 42. Since the traveling particles 24W have a positive charge, they move in the microcapsules 23 toward the pixel electrode 32. Therefore, for example, when the pixel voltage Vpix is set to the voltage Vm for a long time, as shown in FIG. 2B, the electrophoretic particles 24B responsible for the black display gather on the display surface S side, so that the pixel P displays the black display. Do.

Further, depending on the length of time for applying the voltages Vp and Vm, the pixel P can perform an intermediate gradation display between the black display and the white display. Further, for example, when the pixel voltage Vpix is the same voltage as the voltage Vcom (for example, 0V), the electrophoretic particles 24W and 24B do not move, so that the pixel P can maintain the display state. ..

In this example, the migration particle 24W is responsible for the white display and the migration particle 24B is responsible for the black display, but the present invention is not limited to this, and the migration particle 24W is responsible for the bright display and the migration particle 24B is responsible for the bright display. Any color may be used as long as it is responsible for dark display. Further, in this example, the running particle 24W has a positive charge and the running particle 24B has a negative charge, but the present invention is not limited to this, and instead, for example, the running particle 24B May have a positive charge and the electrophoretic particles 24W may have a negative charge. In this case, when the pixel voltage Vpix of the pixel P is set to a positive voltage Vp, the pixel P displays black, and when the pixel voltage Vpix of the pixel P is a negative voltage Vm, the pixel P displays white. Do.

The drive unit 10 (FIG. 1) drives the display unit 20. It has a temperature sensor 11, a storage unit 12, a processing unit 13, a scanning line driving unit 14, and a signal line driving unit 15.

The temperature sensor 11 detects the temperature of the display unit 20.

The storage unit 12 is configured by using, for example, a non-volatile memory, and stores image data Dpic, peripheral area information IRB, a plurality of parameter sets PS1, and a plurality of parameter sets PS2. The image data Dpic includes pixel values for one frame. Peripheral area information IRB is information about the coordinates of pixels P belonging to peripheral areas RB1 and RB2 (described later). The parameter set PS1 includes a set value for generating a signal to be supplied to the pixel P belonging to the peripheral region RB1. In this example, a plurality of parameter sets PS1 are stored so that different signals can be generated depending on the temperature. The parameter set PS2 includes a set value for generating a signal to be supplied to the pixel P belonging to the peripheral region RB2. In this example, a plurality of parameter sets PS2 are stored so that different signals can be generated depending on the temperature.

The processing unit 13 performs predetermined signal processing based on the image signal Spic supplied from the outside. Specifically, the processing unit 13 stores the pixel value (image data Dpic) for one frame included in the image signal Spic in the storage unit 12. Then, the processing unit 13 controls the scanning line driving unit 14 and the signal line driving unit 15 based on the image data Dpic, so that the display unit 20 displays the image. Further, the processing unit 13 detects the pixel region RA that performs black display or intermediate gradation display (that is, display other than white display) based on the image data Dpic, and also includes the peripheral region RB1 of the pixel region RA and its peripheral region RB1. It also has a function of detecting the peripheral region RB2 outside the peripheral region RB1.

FIG. 3A shows a detection example of the peripheral region RB1, and FIG. 3B shows a detection example of the peripheral region RB2. In FIGS. 3A and 3B, the shaded portion indicates the pixel area RA for displaying other than the white display, and the non-shaded portion indicates the pixel area for displaying white.

The processing unit 13 first detects a pixel region RA that displays a display other than the white display, based on the pixel value of each pixel P included in the image data Dpic. Then, the processing unit 13 detects the peripheral region RB1 of the pixel region RA by performing edge detection processing (FIG. 3A). Further, the processing unit 13 detects the peripheral region RB2 outside the peripheral region RB1 (FIG. 3B).

In this way, the processing unit 13 detects the pixel region RA and the peripheral regions RB1 and RB2 based on the image data Dpic. Then, the processing unit 13 stores the information about the coordinates of the pixels P belonging to the peripheral areas RB1 and RB2 in the storage unit 12 as the peripheral area information IRB.

Further, the processing unit 13 performs drawing processing on the display unit 20 based on the detection results of the image data Dpic and the temperature sensor 11. At that time, the processing unit 13 draws in the peripheral areas RB1 and RB2 based on the peripheral area information IRB generated based on the previous image data Dpic. Specifically, the processing unit 13 selects one of the plurality of parameter sets PS1 stored in the storage unit 12 based on the detection result of the temperature sensor 11, and is based on the selected parameter set PS1. The signal line driving unit 15 is controlled so as to generate a signal to be supplied to the pixel P belonging to the peripheral region RB1. Similarly, the processing unit 13 selects one of the plurality of parameter sets PS2 stored in the storage unit 12 based on the detection result in the temperature sensor 11, and based on the selected parameter set PS2, the processing unit 13 selects one. The signal line driving unit 15 is controlled so as to generate a signal to be supplied to the pixel P belonging to the peripheral region RB2.

The processing unit 13 may be configured by hardware, for example, or may be configured by using a processor capable of executing a program.

The scanning line driving unit 14 sequentially selects the pixels P line by line by applying scanning signals Sc to a plurality of scanning lines SCL based on the signals supplied from the processing unit 13.

The signal line driving unit 15 generates a signal Sig including three voltages Vp, Vm, and Vcom based on the signal supplied from the processing unit 13. Then, the signal line driving unit 15 applies this signal Sig to each signal line SGL. As a result, in the pixel P selected by the scanning line driving unit 14, the voltage of the pixel electrode 32 (pixel voltage Vpix) is set based on this signal Sig.

Here, the peripheral region RB1 corresponds to a specific example of the “first peripheral region” in the present disclosure. Peripheral region RB2 corresponds to a specific example of the "second peripheral region" in the present disclosure.

[Operation and action]
Subsequently, the operation and operation of the display device 1 of the present embodiment will be described.

(Overview of overall operation)
First, an outline of the overall operation of the display device 1 will be described with reference to FIG. The temperature sensor 11 detects the temperature of the display unit 20. The storage unit 12 stores the image data Dpic, the peripheral area information IRB, the plurality of parameter sets PS1, and the plurality of parameter sets PS2. The processing unit 13 performs predetermined signal processing based on the image signal Spic. Specifically, the processing unit 13 stores the pixel values for one frame included in the image signal Spic in the storage unit 12 as image data Dpic. Then, the processing unit 13 controls the scanning line driving unit 14 and the signal line driving unit 15 based on the image data Dpic, so that the display unit 20 displays the image. Further, the processing unit 13 detects the pixel region RA that displays other than the white display such as black display based on the image data Dpic, and also has the peripheral region RB1 of the pixel region RA and the outer side of the peripheral region RB1. The peripheral region RB2 is detected, and information about the coordinates of the pixels P belonging to the peripheral regions RB1 and RB2 is stored in the storage unit 12 as the peripheral region information IRB. Then, the processing unit 13 performs drawing processing on the display unit 20 based on the detection results of the image data Dpic and the temperature sensor 11. At that time, the processing unit 13 draws in the peripheral areas RB1 and RB2 based on the peripheral area information IRB generated based on the previous image data Dpic. Specifically, the processing unit 13 selects one of the plurality of parameter sets PS1 stored in the storage unit 12 based on the detection result of the temperature sensor 11, and is based on the selected parameter set PS1. The signal line driving unit 15 is controlled so as to generate a signal to be supplied to the pixel P belonging to the peripheral region RB1. Similarly, the processing unit 13 selects one of the plurality of parameter sets PS2 stored in the storage unit 12 based on the detection result in the temperature sensor 11, and based on the selected parameter set PS2, the processing unit 13 selects one. The signal line driving unit 15 is controlled so as to generate a signal to be supplied to the pixel P belonging to the peripheral region RB2. The scanning line driving unit 14 sequentially selects pixels P line by line by applying scanning signals Sc to a plurality of scanning lines SCL based on the signals supplied from the processing unit 13. The signal line driving unit 15 generates a signal Sig including three voltages Vp, Vm, and Vcom based on the signal supplied from the processing unit 13, and applies this signal Sig to each signal line SGL. The display unit 20 displays an image based on the drive by the drive unit 10.

(Detailed operation)
FIG. 4A shows an operation example of the display device 1 when the display state changes from black display to white display, and FIG. 4A shows waveforms of scanning signals Sc (1) to Sc (N). (B) shows the pixel voltages Vpix (1) to Vpix (N) in the pixels P (1) to P (N), and (C) shows the display state of the pixels P (1) to P (N). Here, for example, the pixel P (1) is one of the plurality of pixels P in the first line of the display unit 20, and the pixel P (N) is the last Nth line in the display unit 20. It is one of a plurality of pixels P of. Further, for example, the scanning signal Sc (1) is a scanning signal Sc applied to the scanning line SCL (1) corresponding to the pixel P (1), and the scanning signal Sc (N) is applied to the pixel P (N). It is a scanning signal Sc applied to the corresponding scanning line SCL (N).

In this example, in the display device 1, drawing processing is performed on the display unit 20 during the period of timings t1 to t9 (drawing period PW), and the pixel voltage Vpix of each pixel P is sequentially set to the negative voltage Vm. This operation will be described in detail below.

First, during the period t1 to t3 (frame period 1F), the scanning line driving unit 14 applies scanning signals Sc (1) to Sc (N) to the scanning lines SCL (1) to SCL (N). By doing so, the pixels P are sequentially selected row by row (FIG. 4A (A)).

For example, during the period t1 to t2 (horizontal period 1H), the scanning signal Sc (1) becomes high level. As a result, the transistor 21 of the pixel P (1) is turned on, and the pixel voltage Vpix (1) of the pixel P (1) is set to the voltage of the signal Sig (voltage Vp in this example) (FIG. 4A (B). )). Then, at the timing t2, the scanning signal Sc (1) changes from a high level to a low level. Along with this, the transistor 21 of the pixel P (1) is turned off. As a result, the pixel electrode 32 of the pixel P (1) is in a floating state, and the pixel voltage Vpix (1) is maintained at the voltage Vp thereafter. Then, the display state in the pixel P (1) begins to change from the black display to the white display (FIG. 4A (C)).

Similarly, the pixel voltages Vpix (2) to Vpix (N) of the pixels P (2) to P (N) are sequentially set to the voltage Vp during the period of the timings t1 to t3 (frame period 1F) (FIG. 4A (B)). Then, the display states of the pixels P (2) to P (N) start to change sequentially from the black display to the white display (FIG. 4A (C)).

After that, in the period from timing t3 to t7, the display device 1 operates in the same manner over a plurality of frame periods 1F. As a result, the pixel voltages Vpix (1) to Vpix (N) of the pixels P (1) to P (N) are maintained at the voltage Vp (FIG. 4A (B)), and the pixels P (1) to P (N) are maintained. ) Continues to change toward the white display (FIG. 4A (C)). As a result, at the timing t7, the pixels P (1) to P (N) are displayed in white.

Then, during the period from timing t7 to t9 (frame period 1F), the scanning line driving unit 14 applies scanning signals Sc (1) to Sc (N) to the scanning lines SCL (1) to SCL (N). By doing so, the pixels P are sequentially selected row by row (FIG. 4A (A)).

For example, during the period from timing t7 to t8 (horizontal period 1H), the scanning signal Sc (1) becomes high level. As a result, the transistor 21 of the pixel P (1) is turned on, and the pixel voltage Vpix (1) of the pixel P (1) is set to the voltage of the signal Sig (voltage Vcom in this example) (FIG. 4A (B). )). Then, at the timing t8, the scanning signal Sc (1) changes from a high level to a low level. Along with this, the transistor 21 of the pixel P (1) is turned off. As a result, the pixel electrode 32 of the pixel P (1) is in a floating state, and the pixel voltage Vpix (1) is maintained at the voltage Vcom thereafter. As a result, the display state in the pixel P (1) is maintained in white display thereafter (FIG. 4A (C)).

Similarly, the pixel voltages Vpix (2) to Vpix (N) of the pixels P (2) to P (N) are sequentially set to the voltage Vcom during this timing t7 to t8 (horizontal period 1H) (FIG. 4A (B)). Then, the display state in the pixels P (2) to P (N) is maintained in white display (FIG. 4A (C)).

FIG. 4B shows an operation example of the display device 1 when the display state changes from white display to black display, and FIG. 4B shows waveforms of scanning signals Sc (1) to Sc (N). (B) shows the pixel voltages Vpix (1) to Vpix (N) in the pixels P (1) to P (N), and (C) shows the display state of the pixels P (1) to P (N).

First, during the period t1 to t3 (frame period 1F), the scanning line driving unit 14 applies scanning signals Sc (1) to Sc (N) to the scanning lines SCL (1) to SCL (N). By doing so, the pixels P are sequentially selected row by row (FIG. 4B (A)). As a result, the pixel voltages Vpix (1) to Vpix (N) of the pixels P (1) to P (N) are sequentially set to the voltage Vm during the period of the timings t1 to t3 (frame period 1F) (FIG. 4B (B)). Then, the display states of the pixels P (1) to P (N) start to change sequentially from the white display to the black display (FIG. 4B (C)).

After that, in the period from timing t3 to t7, the display device 1 operates in the same manner over a plurality of frame periods 1F. As a result, the pixel voltages Vpix (1) to Vpix (N) of the pixels P (1) to P (N) are maintained at the voltage Vm (FIG. 4B (B)), and the pixels P (1) to P (N) are maintained. ) Continues to change toward the black display (FIG. 4B (C)). As a result, at the timing t7, the pixels P (1) to P (N) are displayed in black.

Then, during the period from timing t7 to t9 (frame period 1F), the scanning line driving unit 14 applies scanning signals Sc (1) to Sc (N) to the scanning lines SCL (1) to SCL (N). By doing so, the pixels P are sequentially selected row by row (FIG. 4B (A)). As a result, the pixel voltages Vpix (1) to Vpix (N) of the pixels P (1) to P (N) are sequentially set to the voltage Vcom during this timing t7 to t9 (frame period 1F) (FIG. 4B (B)). Then, the display state of the pixels P (1) to P (N) is maintained in black (FIG. 4B (C)).

In this way, in the display device 1, the drawing process is performed in the drawing period PW including the plurality of frame periods 1F.

In the examples of FIGS. 4A and 4B, the display state of all the pixels P of the display device 1 was changed. On the other hand, when a part of the display image is rewritten, the display state of the pixel P related to the part of the image is changed, and the display state of the other pixels P is maintained. Specifically, it is desirable to supply the voltages Vp and Vm only to the pixels P that change the display state, and to supply the voltage Vcom to the pixels P that maintain the display state. As a result, the display device 1 can suppress flicker of the display image as compared with the case where the display states of all the pixels P are reset.

In this way, when only the pixel P that changes the display state is partially rewritten, so-called edge ghost may occur as described below. Two reference examples E1 and E2 in which edge ghosts can occur will be described below.

5A and 5B show a display image according to Reference Example E1, FIG. 5A shows a display example when a rectangular black object OBJ1 is displayed, and FIG. 5B shows a display example in which the black object OBJ1 is displayed as a white object OBJ2. A display example when rewritten is shown. FIG. 6A shows the states of the pixels PA, PB1 and PB2 in FIG. 5A. FIG. 6B shows the states of the pixels PA, PB1 and PB2 in FIG. 5B. The pixel PA is a pixel P belonging to the pixel region RA displaying the object OBJ1, the pixel PB1 is the pixel P belonging to the peripheral region RB1 of the pixel region RA, and the pixel PB2 is the peripheral region outside the peripheral region RB1. It is a pixel P belonging to RB2.

For example, when the display unit 20 is displaying white over the entire screen, and then the display unit 20 is to display the black object OBJ1 as shown in FIG. 5A, the pixel area The pixel voltage Vpix of the pixel P belonging to RA is set to a negative voltage Vm. At that time, the pixel voltage Vpix of the pixel P belonging to the peripheral regions RB1 and RB2 is set to the voltage Vcom in this example. In this case, as shown in FIG. 6A, the pixel PA can display black. At this time, a part of the electric field generated by the pixel PA also enters the pixel P in the vicinity of the pixel PA, and the electrophoresis particles 24B and 24W may move in the pixel P in the vicinity according to the electric field. In this example, in the pixel PB1 next to the pixel PA, some of the electrophoretic particles 24B are moving toward the counter electrode 42, and some of the electrophoretic particles 24W are moving toward the pixel electrode 32. As a result, the pixel PB1 is displayed in gray, for example. As a result, as shown in FIG. 5A, a gray ring is displayed around the object OBJ1.

Next, when the display unit 20 displays the white object OBJ2 so as to overlap the object OBJ1 as shown in FIG. 5B, the pixel voltage Vpix of the pixel PA belonging to the pixel region RA is positive. The voltage is set to Vp. At that time, the pixel voltage Vpix of the pixels PB1 and PB2 belonging to the peripheral regions RB1 and RB2 are both set to the voltage Vcom in this example. In this case, as shown in FIG. 6B, the pixel PA can display white. However, in this example, in the pixel PB1, some of the electrophoretic particles 24B do not return near the pixel electrode 32, and some of the electrophoretic particles 24W do not return near the counter electrode 42. As a result, as shown in FIG. 5B, a gray ring remains around the object OBJ2. That is, it is expected that the display unit 20 displays white on one surface by rewriting the black object OBJ1 to the white object OBJ2, but in this example, the gray ring is displayed as an edge ghost.

In order to suppress such an edge ghost, a method of setting the pixel voltage Vpix of the pixel P belonging to the peripheral region RB1 to the voltage Vp for a short time, for example, can be considered. Reference example E2 when this method is used will be described below.

FIG. 7 shows a display image according to Reference Example E2, FIG. 7A shows a display example when a rectangular black object OBJ1 is displayed, and FIG. 7B shows a display example in which the black object OBJ1 is displayed as a white object OBJ2. A display example when rewritten is shown. FIG. 8A shows the states of the pixels PA, PB1 and PB2 in FIG. 7A. FIG. 8B shows the states of the pixels PA, PB1 and PB2 in FIG. 7B.

Also in this example, when the black object OBJ1 is displayed on the display unit 20, the pixel voltage Vpix of the pixel P belonging to the pixel region RA is set to a negative voltage Vm, and the pixel voltage of the pixel P belonging to the peripheral regions RB1 and RB2 is set. Both Vpix are set to voltage Vcom. As a result, as shown in FIGS. 7A and 8A, a gray ring is displayed around the object OBJ1.

Next, as shown in FIG. 7B, when the display unit 20 displays the white object OBJ2 so as to overlap the object OBJ1, the pixel voltage Vpix of the pixel P belonging to the pixel region RA is a positive voltage. It is set to Vp. At that time, in this example, the pixel voltage Vpix of the pixel P belonging to the peripheral region RB1 is set to the voltage Vp for a short time. The pixel voltage Vpix of the pixel P belonging to the peripheral region RB2 is set to the voltage Vcom. In this case, as shown in FIG. 8B, for example, the pixels PA and PB1 can be displayed in white. However, a part of the electric field generated by the pixel PB1 also enters the pixel P in the vicinity of the pixel PA, and the electrophoresis particles 24B and 24W may move in the pixel P in the vicinity according to the electric field. In this example, in the pixel PB2 adjacent to the pixel PB1, some of the electrophoretic particles 24B are moving toward the counter electrode 42, and some of the electrophoretic particles 24W are moving toward the pixel electrode 32. As a result, the pixel PB2 is displayed in gray, for example. As a result, as shown in FIG. 7B, the gray ring is displayed as an edge ghost.

Such a phenomenon becomes remarkable when the microcapsules 23 having a high moving speed of the electrophoretic particles 24B and 24W are used. That is, when the image is rewritten in a short time, it is desired to increase the moving speed of the electrophoretic particles 24B and 24W, but in that case, the edge coast may easily occur.

Therefore, in the display device 1 according to the present embodiment, the pixel voltage Vpix of the pixel P belonging to the peripheral region RB1 is set to the voltage Vp for a short time, for example, and the pixel voltage Vpix of the pixel P belonging to the peripheral region RB2 is set to, for example. Set the voltage Vp for a shorter time.

9A and 9B show a display image according to the present embodiment, FIG. 9A shows a display example when a square black object OBJ1 is displayed, and FIG. 9B shows a display example of the black object OBJ1 being displayed as a white object OBJ2. A display example when rewritten to is shown. FIG. 10A shows the states of the pixels PA, PB1 and PB2 in FIG. 9A. FIG. 10B shows the states of the pixels PA, PB1 and PB2 in FIG. 9B.

When displaying the black object OBJ1 on the display unit 20, the drive unit 10 sets the pixel voltage Vpix of the pixel P belonging to the pixel region RA to a negative voltage Vm, and the pixel of the pixel P belonging to the peripheral regions RB1 and RB2. Set both voltage Vpix to voltage Vcom. As a result, as shown in FIGS. 9A and 10A, a gray ring is displayed around the object OBJ1.

Next, when the display unit 20 displays the white object OBJ2 so as to overlap the object OBJ1, the drive unit 10 sets the pixel voltage Vpix of the pixel P belonging to the pixel region RA to a positive voltage Vp. At that time, the drive unit 10 sets the pixel voltage Vpix of the pixel P belonging to the peripheral region RB1 to the voltage Vp for a short time, for example, and sets the pixel voltage Vpix of the pixel P belonging to the peripheral region RB2 to the voltage Vpix for a shorter time, for example. Set to Vp.

FIG. 11 shows an example of the waveform of the pixel voltage Vpix, (A) shows the waveform of the pixel voltage Vpix (PA) of the pixel PA, and (B) shows the waveform of the pixel voltage Vpix (PB1) of the pixel PB1. (C) shows the waveform of the pixel voltage Vpix (PB2) of the pixel PB2. In this example, during the period of timings t11 to t16 (drawing period PW), the driving unit 10 performs drawing processing on the display unit 20. Specifically, first, at the timing t12, the drive unit 10 sets the pixel voltage Vpix (PA) of the pixel PA to a positive voltage Vp (FIG. 11 (A)). Then, at the timing t13, the drive unit 10 sets the pixel voltage Vpix (PB1) of the pixel PB1 to a positive voltage Vp (FIG. 11 (B)). Then, at the timing t14, the drive unit 10 sets the pixel voltage Vpix (PB2) of the pixel PB2 to a positive voltage Vp (FIG. 11 (C)). Then, at the timing t15, the drive unit 10 sets the pixel voltages Vpix (PA), Vpix (PB1), and Vpix (PB2) to the voltage Vcom (FIGS. 11A to 11C).

Here, the pixel voltage Vpix (PB1) of the pixel PB1 corresponds to a specific example of the "first pulse signal" in the present disclosure. The pixel voltage Vpix (PB2) of the pixel PB2 corresponds to a specific example of the "second pulse signal" in the present disclosure. The pixel voltage Vpix (PA) of the pixel PA corresponds to a specific example of the "fourth pulse signal" in the present disclosure.

In this way, the drive unit 10 sets the pixel voltage Vpix of the pixel P belonging to the peripheral region RB1 to the voltage Vp for a short time, and sets the pixel voltage Vpix of the pixel P belonging to the peripheral region RB2 to the voltage Vp for a shorter time. Set to. As a result, in the display device 1, as shown in FIG. 10B, for example, the possibility that the pixels PB1 and PB2 are displayed in gray can be reduced, so that edge ghosting occurs as shown in FIG. 9B. The risk can be reduced.

In this example, the black object OBJ1 is displayed, but the present invention is not limited to this, and the object OBJ1 having a halftone color may be displayed.

FIG. 12 shows an example of the waveform of the pixel voltage Vpix when the white object OBJ2 is displayed after displaying the intermediate gradation color object OBJ1, and FIG. 12A shows the pixel voltage Vpix (PA) of the pixel PA. (B) shows the waveform of the pixel voltage Vpix (PB1) of the pixel PB1, and (C) shows the waveform of the pixel voltage Vpix (PB2) of the pixel PB2. In this example, during the period of timings t21 to t27 (drawing period PW), the driving unit 10 performs drawing processing on the display unit 20. Specifically, first, the drive unit 10 sets the pixel voltage Vpix (PA) of the pixel PA to a negative voltage Vm at the timing t22, and sets the pixel voltage Vpix (PA) to a positive voltage Vp at the timing t23. Set (Fig. 12 (A)). That is, in this example, in order to display the white object OBJ2 after displaying the halftone color object OBJ1, the display state of the pixel PA is once black and then white. Further, the drive unit 10 sets the pixel voltage Vpix (PB1) to a positive voltage Vp at the timing t24 (FIG. 12 (B)), and sets the pixel voltage Vpix (PB2) to a positive voltage Vp at the timing t25. (Fig. 12 (C)). Then, at the timing t26, the drive unit 10 sets the pixel voltages Vpix (PA), Vpix (PB1), and Vpix (PB2) to the voltage Vcom (FIGS. 12A to 12C).

Even in this case, in the display device 1, for example, the possibility that the pixels PB1 and PB2 are displayed in gray can be reduced, so that the possibility that edge ghosting occurs can be reduced.

Next, the operation of the drive unit 10 when a certain image data Dpic is received will be described in detail.

FIG. 13 shows an operation example of the drive unit 10. The driving unit 10 performs drawing processing on the display unit 20 based on the received image data Dpic. At that time, the drive unit 10 draws in the peripheral areas RB1 and RB2 based on the peripheral area information IRB generated based on the previous image data Dpic. This operation will be described in detail below.

First, when the drive unit 10 receives the image data Dpic, the drive unit 10 starts driving each pixel P that changes the display state in the areas other than the peripheral areas RB1 and RB2 based on the image data Dpic (step S101). ). Specifically, when the processing unit 13 first receives the image data Dpic, the processing unit 13 stores the image data Dpic in the storage unit 12. Further, the processing unit 13 identifies the peripheral areas RB1 and RB2 based on the peripheral area information IRB stored in the storage unit 12. Then, the drive unit 10 starts driving each pixel P that changes the display state in the regions other than the peripheral regions RB1 and RB2 based on the image data Dpic.

Next, the processing unit 13 selects one of the pixels P belonging to the peripheral regions RB1 and RB2 as the target pixel PZ to be processed (step S102).

Next, the processing unit 13 acquires the temperature T of the display unit 20 based on the detection result of the temperature sensor 11 (step S103).

Next, the processing unit 13 confirms whether or not the pixel value in the target pixel PZ indicates white display based on the image data Dpic (step S104). When the pixel value in the target pixel PZ indicates intermediate gradation display or black display (“N” in step S104), the drive unit 10 corresponds to the pixel value of the target pixel PZ. The drive is started (step S105), and the process proceeds to step S110.

In step S104, when the pixel value in the target pixel PZ indicates white display (“Y” in step S104), the processing unit 13 determines whether or not the target pixel PZ is a pixel belonging to the peripheral region RB1. Is confirmed (step S106). When the target pixel PZ is a pixel belonging to the peripheral region RB1 (“Y” in step S106), the processing unit 13 has a plurality of parameters stored in the storage unit 12 based on the temperature T acquired in step S103. From the set PS1, the parameter set PS1 corresponding to the temperature T is selected (step S107). When the target pixel PZ is not a pixel belonging to the peripheral region RB1 (“N” in step S106), the processing unit 13 has a plurality of stored units 12 stored in the storage unit 12 based on the temperature T acquired in step S103. The parameter set PS2 corresponding to the temperature T is selected from the parameter set PS2 of (step S108).

Next, the drive unit 10 drives the target pixel PZ (step S109).

FIG. 14 shows a driving operation for the target pixel PZ. First, the processing unit 13 confirms whether or not the driving for the pixels P in the regions other than the peripheral regions RB1 and RB2, which started driving in step S101, has already been completed (step S121). Specifically, for example, in the example of FIG. 11, when the timing of performing this processing is earlier than the timing t12, the processing unit 13 has not yet started driving the pixel PA, and the timing t12 When it is within the period of ~ t15, the pixel PA is driven. Therefore, when the timing of performing this processing is earlier than the timing t15, the processing unit 13 determines that the driving for the pixel PA has not been completed yet. On the other hand, when the timing of performing this processing is later than the timing t15, the processing unit 13 determines that the driving for the pixel PA has already been completed. In this way, the processing unit 13 confirms whether or not the driving of the pixels P in the regions other than the peripheral regions RB1 and RB2 has already been completed. If the drive has already been completed (“Y” in step S121), the process proceeds to step S124.

In step S121, when the drive has not been completed yet (“N” in step S121), the processing unit 13 determines the drive end timing for the pixel P in the area other than the peripheral areas RB1 and RB2 and the drive for the target pixel PZ. It is confirmed whether or not the end timing can be matched (step S122). Specifically, the processing unit 13 first obtains the drive time for the target pixel PZ based on the parameter set selected in steps S108 and S109. Specifically, for example, in the example of FIG. 11, when the target pixel PZ is the pixel PB1, the processing unit 13 has a drive time TB1 (timing t13) based on the parameter set selected in steps S108 and S109. ~ Time length of the period of t15) is calculated. Then, for example, when the timing at which this processing is performed is before the timing t13 which is earlier than the timing t13 which is the drive time TB1 before the timing t15, the processing unit 13 determines the pixels P in the regions other than the peripheral regions RB1 and RB2. For example, it is determined that the drive end timing for the pixel PA) and the drive end timing for the target pixel PZ (for example, the pixel PB1) can be matched. On the other hand, when the timing of performing this processing is later than the timing t13, the processing unit 13 determines the drive end timing for the pixel P (for example, the pixel PA) in the regions other than the peripheral regions RB1 and RB2. It is determined that the drive end timing for the target pixel PZ (for example, pixel PB1) cannot be matched. The “match” of the drive end timing includes not only an exact match but also a case where the drive end timing belongs to one frame period (1F) having the same. In this way, the processing unit 13 confirms whether or not the drive end timing can be matched. If the drive end timings cannot be matched (“N” in step S122), the process proceeds to step S124.

When the drive end timing can be matched in step S122 (“Y” in step S122), the processing unit 13 sets the drive start timing for the target pixel PZ so that the drive end timing matches. (Step S123). As a result, the drive unit 10 then starts driving the target pixel PZ when the drive start timing is reached.

Further, in step S121, when the drive has already been completed (“Y” in step S121), or when the drive end timing cannot be matched in step S122 (“N” in step S122), the drive is driven. The unit 10 immediately starts driving the target pixel PZ based on the parameter set selected in steps S108 and S109 (step S124). In this case, the drive end timing for the target pixel PZ is later than the drive end timing for the pixels P in the areas other than the peripheral areas RB1 and RB2, but even in this case, the possibility of edge ghosting can be reduced. it can. Then, this subroutine ends.

Then, this subroutine ends.

Next, as shown in FIG. 13, the processing unit 13 confirms whether or not all the pixels P belonging to the peripheral regions RB1 and RB2 have been selected (step S110). When all the pixels P have not been selected yet (“N” in step S110), the processing unit 13 targets one of the unselected pixels P among the pixels P belonging to the peripheral areas RB1 and RB2. It is selected as the pixel PZ (step S111), and the process proceeds to step S103. Then, steps S103 to S111 are repeated until all the pixels P are selected.

Then, when all the pixels P are selected (“Y” in step S110), the processing unit 13 detects the peripheral regions RB1 and RB2 based on the image data Dpic (step S112). Then, the processing unit 13 generates the peripheral area information IRB based on the detection result, and stores the peripheral area information IRB in the storage unit 12.

This is the end of this flow.

As described above, in the display device 1, in addition to the pixel P belonging to the peripheral region RB1, the pixel P belonging to the peripheral region RB2 is also driven. As a result, for example, as shown in FIG. 9B, the possibility that the pixels PB1 and PB2 are displayed in gray can be reduced, so that the possibility of edge ghosting can be reduced. The image quality can be improved.

Further, in the display device 1, as shown in FIGS. 11 and 12, the drive time TB2 for the pixel P belonging to the peripheral region RB2 (for example, the pixel PB2) is set as the drive time for the pixel P (for example, the pixel PB1) belonging to the peripheral region RB1. Since it is shorter than TB1, the image quality can be improved. That is, for example, when the drive time TB2 is the same as the drive time TB1, edge ghost may occur in the peripheral region outside the peripheral region RB2. On the other hand, in the display device 1, since the drive time TB2 is shorter than the drive time TB1, the influence of the electric field generated by the pixel P belonging to the peripheral region RB2 on the pixels P outside the peripheral region RB2 can be reduced. Therefore, it is possible to reduce the possibility that edge ghosts will occur in the peripheral region outside the peripheral region RB2. As a result, the image quality of the display device 1 can be improved.

Further, in the display device 1, as shown in FIGS. 11 and 12, the drive end timing for the pixel P (for example, pixel PA) in the region other than the peripheral regions RB1 and RB2 and the pixel P belonging to the peripheral regions RB1 and RB2 (for example). Since the drive end timing for the pixels PB1 and PB2) is matched, the image quality can be improved. That is, for example, when the drive end timing for the pixels PB1 and PB2 is earlier than the drive end timing for the pixel PA, the electric field generated by the pixel PA becomes the pixel PB1 or the like after the drive for the pixels PB1 and PB2 is completed. It may affect and cause edge ghosts. On the other hand, in the display device 1, since the drive end timing for the pixel PA and the drive end timing for the pixels PB1 and PB2 are made to match, the possibility of edge ghosting can be reduced. As a result, the image quality of the display device 1 can be improved.

Further, in the display device 1, the drive unit 10 selects a parameter set PS1 corresponding to the temperature T from the plurality of parameter sets PS1, and based on this parameter set PS1, a signal to be supplied to the pixel P belonging to the peripheral region RB1. Was generated. Similarly, the drive unit 10 selects the parameter set PS2 corresponding to the temperature T from the plurality of parameter sets PS2, and generates a signal to be supplied to the pixel P belonging to the peripheral region RB2 based on the parameter set PS2. As a result, the image quality of the display device 1 can be improved. That is, the characteristics of the display unit 20 can change depending on the temperature T. Therefore, it is desirable to change the drive times TB1, TB2, etc. according to the temperature T. Since the display device 1 generates a signal to be supplied to the pixels P belonging to the peripheral regions RB1 and RB2 based on the temperature T, it is possible to effectively reduce the possibility of edge ghosting occurring at various temperatures. As a result, the image quality can be improved.

Further, in the display device 1, drawing is performed in the peripheral areas RB1 and RB2 based on the peripheral area information IRB generated based on the previous image data Dpic. Thereby, for example, the amount of calculation performed when new image data Dpic is supplied can be reduced. As a result, in the display device 1, the time from the supply of the image data Dpic to the end of drawing can be shortened.

[effect]
As described above, in the present embodiment, in addition to the pixels belonging to the peripheral region RB1, the pixels belonging to the peripheral region RB2 are also driven, so that the image quality can be improved.

In the present embodiment, the drive time for the pixels belonging to the peripheral region RB2 is shorter than the drive time for the pixels belonging to the peripheral region RB1, so that the image quality can be improved.

In the present embodiment, the drive end timing for the pixels in the regions other than the peripheral regions RB1 and RB2 and the drive end timing for the pixels belonging to the peripheral regions RB1 and RB2 are matched, so that the image quality can be improved.

In the present embodiment, since the signal to be supplied to the pixels belonging to the peripheral regions RB1 and RB2 is generated based on the temperature, the image quality can be improved.

In the present embodiment, drawing is performed in the peripheral areas RB1 and RB2 based on the peripheral area information generated based on the previous image data. Therefore, from the time when the image data is supplied until the drawing is completed. Time can be shortened.

[Modification 1]
In the above embodiment, the pixel voltage Vpix of the pixels P belonging to the peripheral regions RB1 and RB2 is set to the positive voltage Vp, but the present invention is not limited to this. Alternatively, as in the display device 1A shown in FIG. 15, the pixel voltage Vpix may be set to a negative voltage Vm before the pixel voltage Vpix is set to a positive voltage Vp. In this example, the drive unit 10A of the display device 1A performs drawing processing on the display unit 20 during the period of timings t31 to t39 (drawing period PW). Specifically, first, the drive unit 10A sets the pixel voltage Vpix (PA) of the pixel PA to a negative voltage Vm at the timing t32, and sets the pixel voltage Vpix (PA) to a positive voltage Vp at the timing t33. Set (Fig. 15 (A)). Further, the drive unit 10A sets the pixel voltage Vpix (PB1) of the pixel PB1 to a negative voltage Vm at the timing t34 and sets the pixel voltage Vpix (PB1) to a positive voltage Vm at the timing t35, as in the case of the pixel PA. The voltage is set to Vp (FIG. 15 (B)). Then, the drive unit 10A sets the pixel voltage Vpix (PB2) of the pixel PB2 to a negative voltage Vm at the timing t36 and sets the pixel voltage Vpix (PB2) to a positive voltage Vm at the timing t37, as in the case of the pixel PA. The voltage is set to Vp (FIG. 15 (C)). Then, at the timing t38, the drive unit 10A sets the pixel voltages Vpix (PA), Vpix (PB1), and Vpix (PB2) to the voltage Vcom (FIGS. 15A to 15C).

[Modification 2]
In the above embodiment, the drive time TB2 for the pixel P belonging to the peripheral region RB2 is shorter than the drive time TB1 for the pixel P belonging to the peripheral region RB1, but the present invention is not limited to this. Instead, for example, as in the display device 1B shown in FIG. 16, the pixel voltage Vpix of the pixel P belonging to the peripheral region RB2 may be lower than the pixel voltage Vpix of the pixel P belonging to the peripheral region RB1. In this example, the drive unit 10B of the display device 1B performs drawing processing on the display unit 20 during the period of timings t41 to t47 (drawing period PW). Specifically, first, the drive unit 10B sets the pixel voltage Vpix (PA) of the pixel PA to a negative voltage Vm at the timing t42, and sets the pixel voltage Vpix (PA) to a positive voltage Vp at the timing t43. Set (Fig. 16 (A)). Further, the drive unit 10B sets the pixel voltage Vpix (PB1) of the pixel PB1 to a positive voltage Vp at the timing t44 (FIG. 16 (B)). Then, the drive unit 10B sets the pixel voltage Vpix (PB2) of the pixel PB2 to the positive voltage Vp1 at the timing t45 (FIG. 16 (C)). This voltage Vp1 is a voltage (Vp1 <Vp) lower than the voltage Vp. Then, at the timing t46, the drive unit 10B sets the pixel voltages Vpix (PA), Vpix (PB1), and Vpix (PB2) to the voltage Vcom (FIGS. 16A to 16C).

In the display device 1B, the present modification is applied to the display device 1 (for example, FIG. 12) according to the above embodiment, but the present modification is not limited to this, and for example, the present modification is applied to the modification 1 (FIG. 15). An example may be applied.

[Modification 3]
In the above embodiment, the pixel voltage Vpix of the pixels P belonging to the peripheral regions RB1 and RB2 is set to the voltage Vp, but the present invention is not limited to this. Instead of this, for example, as in the display device 1C shown in FIG. 17, the pixel voltage Vpix of the pixel P belonging to the peripheral regions RB1 and RB2 may be set to a positive voltage Vp1 lower than the voltage Vp. In this example, the drive unit 10C of the display device 1C performs drawing processing on the display unit 20 during the period of timings t51 to t57 (drawing period PW). Specifically, first, the drive unit 10C sets the pixel voltage Vpix (PA) of the pixel PA to a negative voltage Vm at the timing t52, and sets the pixel voltage Vpix (PA) to a positive voltage Vp at the timing t53. Set (Fig. 17 (A)). Further, the drive unit 10C sets the pixel voltage Vpix (PB1) of the pixel PB1 to the positive voltage Vp1 at the timing t54 (FIG. 17 (B)), and sets the pixel voltage Vpix (PB2) of the pixel PB2 at the timing t55. The positive voltage is set to Vp1 (FIG. 17 (C)). Then, at the timing t56, the drive unit 10C sets the pixel voltages Vpix (PA), Vpix (PB1), and Vpix (PB2) to the voltage Vcom (FIGS. 17A to 17C).

Further, for example, as in the display device 1D shown in FIG. 18, the pixel voltage Vpix of the pixel P belonging to the peripheral regions RB1 and RB2 may be set to the voltage Vp1 in a plurality of times. This makes it possible to reduce the possibility of edge ghosting occurring in the peripheral region outside the peripheral region RB1.

[Modification example 4]
In the above embodiment, the pixels P belonging to the peripheral regions RB1 and RB2 are driven, but the present invention is not limited to this, and the pixels P in one or a plurality of outer peripheral regions may also be driven. The display device 1D according to this modification will be described in detail below.

FIG. 19 shows a display image according to this modification, (A) shows a display example when a square black object OBJ1 is displayed, and (B) shows the black object OBJ1 as a white object OBJ2. A display example when rewritten is shown. FIG. 20A shows the states of the pixels PA, PB1, PB2, and PB3 in FIG. 19A. FIG. 20B shows the states of the pixels PA, PB1, PB2, and PB3 in FIG. 19B. The pixel PB3 is a pixel P belonging to the peripheral region RB3 outside the peripheral region RB2.

When displaying the black object OBJ1 on the display unit 20, the drive unit 10D of the display device 1D sets the pixel voltage Vpix of the pixel P belonging to the pixel region RA to a negative voltage Vm, and peripheral regions RB1, RB2, RB3. The pixel voltage Vpix of the pixel P belonging to is set to the voltage Vcom. As a result, as shown in FIGS. 19A and 20A, a gray ring is displayed around the object OBJ1.

Next, when the display unit 20 displays the white object OBJ2 so as to overlap the object OBJ1, the drive unit 10D sets the pixel voltage Vpix of the pixel P belonging to the pixel region RA to a positive voltage Vp. At that time, the drive unit 10D applies the voltage Vp to the pixels P belonging to the peripheral regions RB1, RB2, and RB3 for a short time.

FIG. 21 shows an example of the waveform of the pixel voltage Vpix, (A) shows the waveform of the pixel voltage Vpix (PA) of the pixel PA, and (B) shows the waveform of the pixel voltage Vpix (PB1) of the pixel PB1. (C) shows the waveform of the pixel voltage Vpix (PB2) of the pixel PB2, and (D) shows the waveform of the pixel voltage Vpix (PB3) of the pixel PB3. In this example, the drive unit 10D performs drawing processing on the display unit 20 during the period of timings t71 to t77 (drawing period PW). Specifically, first, at the timing t72, the drive unit 10D sets the pixel voltage Vpix (PA) of the pixel PA to a positive voltage Vp (FIG. 21 (A)). Then, at the timing t73, the drive unit 10D sets the pixel voltage Vpix (PB1) of the pixel PB1 to a positive voltage Vp (FIG. 21 (B)), and at the timing t74, sets the pixel voltage Vpix (PB2) of the pixel PB2. The positive voltage Vp is set (FIG. 21 (C)), and the pixel voltage Vpix (PB3) of the pixel PB3 is set to the positive voltage Vp at the timing t75 (FIG. 21 (D)). Then, at the timing t76, the drive unit 10D sets the pixel voltages Vpix (PA), Vpix (PB1), Vpix (PB2), and Vpix (PB3) to the voltage Vcom (FIGS. 21 (A) to 21 (D)).

In this way, the drive unit 10D sets the pixel voltage Vpix of the pixel P belonging to the peripheral region RB1 to the voltage Vp for a short time, and sets the pixel voltage Vpix of the pixel P belonging to the peripheral region RB2 to the voltage Vp for a shorter time. Is set to, and the pixel voltage Vpix of the pixel P belonging to the peripheral region RB3 is set to the voltage Vp for a shorter time. As a result, in the display device 1D, as shown in FIG. 20B, for example, the possibility that the pixels PB1, PB2, and PB3 are displayed in gray can be reduced. Therefore, as shown in FIG. 19B, the edge ghost can be reduced. Can be reduced.

[Other variants]
Moreover, you may combine two or more of these modified examples.

<2. Application example>
Next, an application example of the display device described in the above-described embodiment and modification will be described. However, the configuration of the electronic device described below is just an example, and the configuration can be changed as appropriate. The above display device can be applied to various electronic devices or a part of clothing, and the types of the electronic devices and the like are not particularly limited.

(Application example 1)
22A and 22B show the appearance configuration of the electronic book. This electronic book includes, for example, a display unit 110, a housing 120, and an operation unit 130. The operation unit 130 may be provided on the front surface of the housing 120 as shown in FIG. 22A, or may be provided on the side surface of the housing 120 as shown in FIG. 22B. The display unit 110 is composed of the above display device. The display device may be mounted on a PDA (Personal Digital Assistants) or the like having the same configuration as the electronic book shown in FIGS. 22A and 22B.

(Application example 2)
FIG. 23 shows the appearance of a tablet computer. This tablet computer has, for example, a touch panel unit 310 and a housing 320, and the touch panel unit 310 is configured by the above display device.

(Application example 3)
The above-mentioned display device can be applied as a so-called wearable terminal to a part of clothing such as a watch (wrist watch), a bag, clothes, a hat, eyeglasses and shoes. The following is an example of such an electronic device integrated with clothing.

24A and 24B show the appearance of an electronic watch (wristwatch-integrated electronic device). This electronic clock has, for example, a dial (character information display portion) 410 and a band portion (color pattern display portion) 420, and these dial 410 and the band portion 420 include the above display device. Has been done. On the dial 410, for example, various characters and symbols are displayed as shown in FIGS. 24A and 24B by the display drive using the above-mentioned electrophoresis element. The band portion 420 is a portion that can be worn on, for example, an arm or the like. By using the above-mentioned display device in the band portion 420, various color patterns can be displayed, and the design of the band portion 420 can be changed from the example of FIG. 24A to the example of FIG. 24B. it can. In this way, it is possible to realize an electronic device that is also useful in fashion applications.

Although the present technology has been described above with reference to embodiments and modifications, and examples of application to electronic devices, the present technology is not limited to these embodiments and the like, and various modifications are possible.

For example, in each of the above embodiments, the microcapsule type electrophoresis element is used, but the present invention is not limited to this, and other type of electrophoresis elements may be used.

It should be noted that the effects described in the present specification are merely examples and are not limited, and other effects may be obtained.

The present technology can have the following configuration.

(1) The pixel of the first pixel belonging to the first peripheral region outside the pixel region for rewriting a color other than the predetermined color to the predetermined color among a plurality of pixels each having an electrophoresis element and a pixel electrode. The first pixel is driven so that the first pulse signal is generated in the electrode, and the second pulse is applied to the pixel electrode of the second pixel belonging to the second peripheral region outside the first peripheral region. A drive device including a drive unit that drives the second pixel so that a signal is generated.

(2) The driving unit further causes the third pixel to generate a third pulse signal at the pixel electrode of the third pixel belonging to the third peripheral region outside the second peripheral region. The driving device according to (1) above.

(3) The drive unit is
Based on the first image data, a fourth peripheral region outside the pixel region showing a color other than the predetermined color in the first image data, and a fifth peripheral region outside the fourth peripheral region. Detected
The first peripheral region is obtained based on the pixel value of each pixel belonging to the fourth peripheral region in the second image data following the first image data, and each belonging to the fifth peripheral region is obtained. The driving device according to (1) or (2), wherein the second peripheral region is obtained based on the pixel value of the pixel.

(4) The drive device according to any one of (1) to (3), wherein the drive time in the second pulse signal is shorter than the drive time in the first pulse signal.

(5) The drive device according to any one of (1) to (4), wherein the amplitude of the second pulse signal is smaller than the amplitude of the first pulse signal.

(6) The driving unit drives the fourth pixel so that a fourth pulse signal is generated at the pixel electrode of the fourth pixel belonging to the pixel region.
The drive device according to any one of (1) to (5) above, wherein the end timing of the first pulse signal is a timing corresponding to the end timing of the fourth pulse signal.

(7) The drive device according to (6), wherein the drive time in the first pulse signal is shorter than the drive time in the fourth pulse signal.

(8) The driving unit drives the fourth pixel so that a fourth pulse signal is generated at the pixel electrode of the fourth pixel belonging to the pixel region.
The drive device according to any one of (1) to (7) above, wherein the end timing of the second pulse signal is a timing corresponding to the end timing of the fourth pulse signal.

(9) The drive device according to any one of (1) to (8) above, wherein one or both of the first pulse signal and the second pulse signal includes a plurality of pulses.

(10) The first pulse signal includes a first voltage corresponding to the predetermined color, a second voltage, and a third voltage between the first voltage and the second voltage. Including
The second pulse signal has a fourth voltage, a fifth voltage, and a third voltage corresponding to the predetermined color.
Any of the above (1) to (3), the length of the period of the fourth voltage in the second pulse signal is shorter than the length of the period of the first voltage in the first pulse signal. Drive device described in.

(11) The drive device according to (10), wherein the first voltage and the fourth voltage are equal to each other.

(12) The first pulse signal includes a first voltage corresponding to the predetermined color, a second voltage, and a third voltage between the first voltage and the second voltage. Including
The second pulse signal has a fourth voltage, a fifth voltage, and a third voltage corresponding to the predetermined color.
The drive according to any one of (1) to (3), wherein the voltage difference between the fourth voltage and the third voltage is smaller than the voltage difference between the first voltage and the third voltage. apparatus.

(13) The driving unit drives the fourth pixel so that a fourth pulse signal is generated at the pixel electrode of the fourth pixel belonging to the pixel region.
The drive device according to any one of (10) to (12) above, wherein the end timing of the first pulse signal is a timing corresponding to the end timing of the fourth pulse signal.

(14) The driving unit drives the fourth pixel so that a fourth pulse signal is generated at the pixel electrode of the fourth pixel belonging to the pixel region.
The drive device according to any one of (10) to (13), wherein the end timing of the second pulse signal is a timing corresponding to the end timing of the fourth pulse signal.

(15) The drive unit is
Further having a storage unit for storing a plurality of first parameter sets for generating the first pulse signal and a plurality of second parameter sets for generating the second pulse signal.
The first pixel is driven based on one of the plurality of first parameter sets, and the second pixel is driven based on any of the plurality of second parameter sets. The drive device according to any one of (1) to (14).

(16) The drive unit is
It also has a temperature sensor
Based on the detection result in the temperature sensor, one of the plurality of first parameter sets is selected, and one of the plurality of second parameter sets is selected and selected. The driving device according to (15), wherein the first pixel is driven based on the first parameter set, and the second pixel is driven based on the selected second parameter set.

(17) The drive device according to any one of (1) to (16) above, wherein the predetermined color is a color corresponding to a bright display.

(18) The drive device according to any one of (1) to (17) above, wherein the predetermined color is white.

(19) Among a plurality of pixels each having an electrophoresis element and a pixel electrode, the pixel of the first pixel belonging to the first peripheral region outside the pixel region for rewriting a color other than the predetermined color to the predetermined color. The first pixel is driven so that the first pulse signal is generated at the electrode.
A driving method for driving the second pixel so that a second pulse signal is generated in the pixel electrode of the second pixel belonging to the second peripheral region outside the first peripheral region.

(20) A display unit having a plurality of pixels, each of which has an electrophoresis element and a pixel electrode.
The first pulse signal is generated at the pixel electrode of the first pixel belonging to the first peripheral region outside the pixel region for rewriting from a color other than the predetermined color to the predetermined color among the plurality of pixels. While driving one pixel, the second pixel is driven so that a second pulse signal is generated in the pixel electrode of the second pixel belonging to the second peripheral region outside the first peripheral region. A display device with a drive unit.

1,1A to 1D ... Display device, 10,10A to 10D ... Drive unit, 11 ... Temperature sensor, 12 ... Storage unit, 13 ... Processing unit, 14 ... Scanning line drive unit, 15 ... Signal line drive unit, 21 ... Transistor , 22 ... Display element, 23 ... Microcapsule, 24B, 24W ... Running particles, 25 ... Dispersion medium, 26 ... Binder, 30 ... Drive substrate, 31 ... Substrate, 32 ... Pixel electrode, 40 ... Opposite substrate, 41 ... Substrate, 42 ... counter electrode, Dpic ... image data, IRB ... peripheral area information, OBJ1, OBJ2 ... object, P, PA, PB1, PB2, PB3, P (1) to P (N) ... pixel, PS1, PS2 ... parameter set , PW ... drawing period, PZ ... target pixel, RA ... pixel area, RB1, RB2 ... peripheral area, S ... display surface, SCL ... scanning line, Sc, Sc (1) to Sc (N) ... scanning signal, SGL ... Signal line, Spic ... image signal, TB1 to TB3 ... drive time, Vcom, Vm, Vp ... voltage, Vpix, Vpix (1) to Vpix (N), Vpix (PA), Vpix (PB1), Vpix (PB2), Vpix (PB3) ... Pixel voltage.

Claims (19)

Among a plurality of pixels each having an electrophoresis element and a pixel electrode, a first pixel that maintains a display state belonging to a first peripheral region outside a pixel region that is rewritten from a color other than a predetermined color to the predetermined color. The first pixel is driven so that the first pulse signal is generated in the pixel electrode, and the display state belonging to the second peripheral region outside the first peripheral region is maintained. A drive unit for driving the second pixel so that a second pulse signal is generated in the pixel electrode of
The drive time in the first pulse signal overlaps with the drive time in the second pulse signal.
The driving time in the second pulse signal, rather short than the drive time of the first pulse signal,
The first pulse signal includes a first voltage corresponding to the predetermined color and a second voltage.
The second pulse signal includes a third voltage and the second voltage.
A drive device in which the drive time of the third voltage in the second pulse signal is shorter than the drive time of the first voltage in the first pulse signal . The driving unit further causes the third pulse signal to be generated at the pixel electrode of the third pixel in which the display state belonging to the third peripheral region outside the second peripheral region is maintained . The driving device according to claim 1, wherein the pixels of the above are driven. The drive unit
Based on the first image data, a fourth peripheral region outside the pixel region showing a color other than the predetermined color in the first image data, and a fifth peripheral region outside the fourth peripheral region. Detected
The first peripheral region is obtained based on the pixel value of each pixel belonging to the fourth peripheral region in the second image data next to the first image data, and each belonging to the fifth peripheral region is obtained. The driving device according to claim 1, wherein the second peripheral region is obtained based on the pixel value of the pixel. The driving device according to claim 1, wherein the amplitude of the second pulse signal is smaller than the amplitude of the first pulse signal. The driving unit drives the fourth pixel so that a fourth pulse signal is generated at the pixel electrode of the fourth pixel belonging to the pixel region.
The drive device according to claim 1, wherein the end timing of the first pulse signal is a timing corresponding to the end timing of the fourth pulse signal. The drive device according to claim 5, wherein the drive time in the first pulse signal is shorter than the drive time in the fourth pulse signal. The driving unit drives the fourth pixel so that a fourth pulse signal is generated at the pixel electrode of the fourth pixel belonging to the pixel region.
The drive device according to claim 1, wherein the end timing of the second pulse signal is a timing corresponding to the end timing of the fourth pulse signal. The driving device according to claim 1, wherein one or both of the first pulse signal and the second pulse signal includes a plurality of pulses. The first pulse signal further comprises a fourth voltage.
The driving device according to claim 1, wherein the second voltage is a voltage between the first voltage and the fourth voltage . The first voltage and the third voltage are equal to each other.
The drive device according to claim 1 . The drive device according to claim 1, wherein the voltage difference between the third voltage and the second voltage is smaller than the voltage difference between the first voltage and the second voltage . The driving unit drives the fourth pixel so that a fourth pulse signal is generated at the pixel electrode of the fourth pixel belonging to the pixel region.
The drive device according to claim 9, wherein the end timing of the first pulse signal is a timing corresponding to the end timing of the fourth pulse signal. The driving unit drives the fourth pixel so that a fourth pulse signal is generated at the pixel electrode of the fourth pixel belonging to the pixel region.
The drive device according to claim 9, wherein the end timing of the second pulse signal is a timing corresponding to the end timing of the fourth pulse signal. The drive unit
Further having a storage unit for storing a plurality of first parameter sets for generating the first pulse signal and a plurality of second parameter sets for generating the second pulse signal.
The first pixel is driven based on one of the plurality of first parameter sets, and the second pixel is driven based on any of the plurality of second parameter sets. The drive device according to claim 1. The drive unit
It also has a temperature sensor
Based on the detection result in the temperature sensor, one of the plurality of first parameter sets is selected, and one of the plurality of second parameter sets is selected and selected. The driving device according to claim 14, wherein the first pixel is driven based on the first parameter set, and the second pixel is driven based on the selected second parameter set. The drive device according to claim 1, wherein the predetermined color is a color corresponding to a bright display. The drive device according to claim 1, wherein the predetermined color is white. Among a plurality of pixels each having an electrophoresis element and a pixel electrode, a first pixel that maintains a display state belonging to a first peripheral region outside a pixel region that is rewritten from a color other than a predetermined color to the predetermined color. To drive the first pixel so that the first pulse signal is generated in the pixel electrode of
To drive the second pixel so that a second pulse signal is generated in the pixel electrode of the second pixel in which the display state belonging to the second peripheral region outside the first peripheral region is maintained. Including
The drive time in the first pulse signal overlaps with the drive time in the second pulse signal.
The driving time in the second pulse signal, rather short than the drive time of the first pulse signal,
The first pulse signal includes a first voltage corresponding to the predetermined color and a second voltage.
The second pulse signal includes a third voltage and the second voltage.
A driving method in which the driving time of the third voltage in the second pulse signal is shorter than the driving time of the first voltage in the first pulse signal . A display unit having a plurality of pixels, each having an electrophoresis element and a pixel electrode,
A first pulse signal to the pixel electrode of the first pixel whose display state belongs to the first peripheral region outside the pixel region for rewriting from a color other than the predetermined color to the predetermined color among the plurality of pixels. A second pulse signal is driven to the pixel electrode of the second pixel so that the first pixel is driven and the display state belonging to the second peripheral region outside the first peripheral region is maintained. A drive unit for driving the second pixel is provided so that
The drive time in the first pulse signal overlaps with the drive time in the second pulse signal.
The driving time in the second pulse signal, rather short than the drive time of the first pulse signal,
The first pulse signal includes a first voltage corresponding to the predetermined color and a second voltage.
The second pulse signal includes a third voltage and the second voltage.
A display device in which the drive time of the third voltage in the second pulse signal is shorter than the drive time of the first voltage in the first pulse signal .

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