JP6865575B2 - Display devices, display device drive methods and electronic devices - Google Patents

Description

The present invention relates to a display device, a method for driving the display device, and an electronic device.

The electrophoresis display device is a display device capable of displaying for a long time because of its low power consumption. As such an electrophoresis display device, a device in which a transistor for switching and a memory circuit are provided in a pixel is known (see, for example, Patent Document 1).

That is, the electrophoresis display device described in Patent Document 1 is provided on a scanning line, a data line, a first control line, a second control line, a pixel electrode provided on the pixel, and a pixel. It includes a pixel switching element and a memory circuit, and a counter electrode facing the pixel electrode. Then, an electrophoresis dispersion is provided between the pixel electrode and the counter electrode, and an electric field is generated between the pixel electrode and the counter electrode to allow the electrophoresis particles in the electrophoresis dispersion to run and display. Do.

In such an electrophoresis display device, when switching the display, for example, the pixel electrode and the counter electrode are driven by periodically shifting the potential of the counter electrode while the potential of the pixel electrode is constant. A potential difference is generated between the and. An electric field is generated by this potential difference, and the display is switched by the electrophoresis of the electrophoresis particles.

Here, FIG. 16 is a timing chart showing a drive sequence of a conventional electrophoresis display device. Vcom in FIG. 16 is the potential of the counter electrode, Vpix (L) is the potential supplied to the pixel electrode when the image data held in the memory circuit is at a low level, and Vpix (H) is the potential of the memory circuit. This is the potential supplied to the pixel electrodes when the retained image data is at a high level.

In the timing chart shown in FIG. 16, when the potential Vpix (H) of the pixel electrode is set to 0 and the potential Vcom of the counter electrode is periodically switched between 0 and V, the potential difference Vpix between the pixel electrode and the counter electrode (H) -Vcom periodically switches between 0 and V. On the other hand, when the potential Vpix (L) of the pixel electrode is V and the potential Vcom of the counter electrode is periodically switched between 0 and V, the potential difference Vpix (L) -Vcom between the pixel electrode and the counter electrode is , Again, it switches periodically between 0 and V.

JP-A-2009-86402

When the potential difference between the pixel electrode and the counter electrode is periodically switched as described above, the electrophoretic particles can be run during the period when the potential difference between the pixel electrode and the counter electrode is V, while the potential difference. During the period when is 0, the electrophoretic particles cannot be run. Therefore, the time required for rewriting the display is longer because the period including the period when the potential difference is 0 is included.

An object of the present invention is to provide a display device and a method for driving the display device, which can rewrite the display in a shorter time without increasing the voltage applied between the electrodes, and an electronic device having a high display rewriting speed. It is in.

Such an object is achieved by the following invention.
The display device of the present invention includes a substrate including an image display unit including pixels and a substrate.
1st power line, 2nd power line and 3rd power line,
Pixel electrodes provided corresponding to the pixels and
A memory circuit provided corresponding to the pixel and capable of holding and outputting either the first state or the second state, and
The common electrode connected to the third power supply line and
A power supply unit including a first voltage end that outputs a first potential and a second voltage end that outputs a second potential different from the first potential.
A common electrode switch circuit that alternately conducts between the third power supply line and either the first voltage end or the second voltage end.
A second power line provided between the first power supply line and the pixel electrode, which conducts when the output from the memory circuit is in the first state and shuts off when the output from the memory circuit is in the second state. 1 switch circuit and
A second power line provided between the second power supply line and the pixel electrode, which conducts when the output from the memory circuit is in the second state and shuts off when the output from the memory circuit is in the first state. 2 switch circuit and
When the third power supply line is conducting with the second voltage end, it conducts between the first power supply line and the first voltage end, and the third power supply line conducts with the first voltage end. When there is, a third switch circuit that cuts off between the first power supply line and the first voltage end, and
It is characterized by having.

This makes it possible to obtain a display device capable of rewriting the display in a shorter time without increasing the voltage applied between the electrodes. On the contrary, the power consumption of the display device can be suppressed without lengthening the time required for rewriting the display.

Further, in the display device of the present invention, when the third power supply line is conducting with the first voltage end, the second power supply line and the second voltage end are conducted with each other, and the third power supply line becomes conductive. It is preferable to have a fourth switch circuit that cuts off between the second power supply line and the second voltage end when it is conducting with the second voltage end.

As a result, the effect of obtaining a display device capable of rewriting the display in a shorter time without increasing the voltage applied between the electrodes can be enjoyed regardless of the display content.

The display device of the present invention preferably has a first capacitor provided between the first power supply line and the third power supply line.

As a result, sufficient electrical energy can be stored in the first capacitor. As a result, it is possible to speed up the rewriting of the display even during the period when the voltage is not directly applied from the power supply unit.

The display device of the present invention preferably has a second capacitor provided between the second power supply line and the third power supply line.

As a result, sufficient electrical energy can be stored in the second capacitor. As a result, it is possible to speed up the rewriting of the display even during the period when the voltage is not directly applied from the power supply unit.

In the display device of the present invention, further
Scanning line and
Data line and
A pixel switching element provided corresponding to the pixel and provided between the scanning line and the data line and the memory circuit,
It is preferable to have.

As a result, it is possible to operate so as to input the image data based on the image signal supplied from the data line into the memory circuit.

The display device of the present invention preferably further has an electro-optical material layer provided between the pixel electrode and the common electrode.

As a result, the time required for electrophoresis of the electrophoretic particles contained in the electro-optical material layer can be shortened without increasing the voltage applied between the pixel electrode and the common electrode, and the display can be rewritten in a shorter time. The device is obtained.

The display device of the present invention includes a substrate including an image display unit including pixels and a substrate.
1st power line, 2nd power line and 3rd power line,
A power source that outputs a first potential, a second potential different from the first potential, and a third potential and a fourth potential having the same high-low relationship as the high-low relationship between the first potential and the second potential. Department and
Power supply modulation in which the first potential is supplied to the first power supply line, the second potential is supplied to the second power supply line, and the third potential and the fourth potential are alternately supplied to the third power supply line. Department and
Pixel electrodes provided corresponding to the pixels and
A memory circuit provided corresponding to the pixel and capable of holding and outputting either the first state or the second state, and
The common electrode connected to the third power supply line and
A second power line provided between the first power supply line and the pixel electrode, which conducts when the output from the memory circuit is in the first state and shuts off when the output from the memory circuit is in the second state. 1 switch circuit and
A second power line provided between the second power supply line and the pixel electrode, which conducts when the output from the memory circuit is in the second state and shuts off when the output from the memory circuit is in the first state. 2 switch circuit and
Have,
When the fourth potential is supplied to the third power supply line, the power supply modulation unit conducts between the first power supply line and the power supply unit, and the third potential is supplied to the third power supply line. It is characterized by including a third switch circuit that cuts off between the first power supply line and the power supply unit when the power supply line is used.

This makes it possible to obtain a display device capable of rewriting the display in a shorter time without increasing the voltage applied between the electrodes. On the contrary, the power consumption of the display device can be suppressed without lengthening the time required for rewriting the display.

In the display device of the present invention, the power supply modulation unit further conducts between the second power supply line and the power supply unit when the third potential is supplied to the third power supply line, and the third power supply line conducts the third power supply line. It is preferable to provide a fourth switch circuit that cuts off between the second power supply line and the power supply unit when the fourth potential is supplied to the power supply line.

As a result, the effect of obtaining a display device capable of rewriting the display in a shorter time without increasing the voltage applied between the electrodes can be enjoyed regardless of the display content.

The driving method of the display device of the present invention includes a substrate including an image display unit including pixels and a substrate.
1st power line, 2nd power line and 3rd power line,
A power supply unit that applies a potential difference between the first power supply line and the third power supply line and between the second power supply line and the third power supply line, respectively.
Pixel electrodes provided corresponding to the pixels and
A memory circuit provided corresponding to the pixel and capable of holding and outputting either the first state or the second state, and
The common electrode connected to the third power supply line and
A second power line provided between the first power supply line and the pixel electrode, which conducts when the output from the memory circuit is in the first state and shuts off when the output from the memory circuit is in the second state. 1 switch circuit and
A second power line provided between the second power supply line and the pixel electrode, which conducts when the output from the memory circuit is in the second state and shuts off when the output from the memory circuit is in the first state. 2 switch circuit and
Is a method of driving a display device having
The first step of applying a potential difference between the first power supply line and the third power supply line and between the second power supply line and the third power supply line, and
In the first step, the second step of electrically floating the power supply line having a potential difference between the first power supply line and the third power supply line among the second power supply lines,
It is characterized by having.

As a result, the display can be rewritten even during the period when the voltage is not directly applied from the power supply unit by charging in the first step and discharging in the second step. As a result, the display rewriting speed can be increased.

In the driving method of the display device of the present invention, in the first step, either the first power supply line and the third power supply line or the second power supply line and the third power supply line are charged. And
In the second step, it is preferable to generate an electric field between the pixel electrode and the common electrode by discharging the electric charge charged in the first step.
As a result, the display rewriting speed can be increased.

The electronic device of the present invention is characterized by comprising the display device of the present invention.
As a result, an electronic device having a high display switching speed can be obtained.

It is sectional drawing which shows the electrophoretic display apparatus to which 1st Embodiment of the display apparatus of this invention was applied. It is a block diagram which shows the active matrix circuit board and common electrode shown in FIG. It is a figure which shows the circuit structure in one pixel and common electrode of the active matrix circuit board shown in FIG. It is a timing chart which shows the driving method of the display device including the active matrix circuit board shown in FIG. 3 when the image data is "L" (first state). It is a timing chart which shows the driving method of the display device including the active matrix circuit board shown in FIG. 3 when the image data is "H" (second state). It is a figure which shows the modification which modified a part of the circuit structure shown in FIG. It is a figure which shows the circuit structure in one pixel and common electrode of the active matrix circuit board included in the 2nd Embodiment of the display device of this invention. It is a timing chart which shows the driving method of the display device including the active matrix circuit board shown in FIG. 7. It is a timing chart which shows the driving method of the display device including the active matrix circuit board shown in FIG. 7. It is a figure which shows the circuit structure in one pixel and common electrode of the active matrix circuit board included in the 3rd Embodiment of the display device of this invention. It is a figure which shows the circuit structure in one pixel and common electrode of the active matrix circuit board included in 4th Embodiment of the display device of this invention. It is a front view of the wristwatch to which the embodiment of the electronic device of this invention is applied. It is a side sectional view of the wristwatch shown in FIG. It is a perspective view which shows the structure of the electronic paper to which the embodiment of the electronic device of this invention is applied. It is a perspective view which shows the structure of the electronic notebook to which the embodiment of the electronic device of this invention is applied. It is a timing chart which shows the drive sequence of the conventional electrophoresis display device.

Hereinafter, the display device of the present invention, the driving method of the display device, and a preferred embodiment of the electronic device will be described with reference to the accompanying drawings.

<< First Embodiment >>
<Display device>
First, the first embodiment of the present invention will be described.

FIG. 1 is a cross-sectional view showing an electrophoresis display device to which the first embodiment of the display device of the present invention is applied. In the following description, for convenience of explanation, the upper side in FIG. 1 will be referred to as “upper” and the lower side will be referred to as “lower”. Further, as shown in FIG. 1, two directions orthogonal to each other in the display surface of the electrophoresis display device 1 are defined as "X-axis direction" and "Y-axis direction", and directions orthogonal to these two directions are "Z-axis". Direction. "

The electrophoresis display device 1 shown in FIG. 1 is a display device that displays a desired image by utilizing the migration of particles. The electrophoresis display device 1 includes a backplane 10 including an electrode substrate 120 and a pixel electrode 121, and a frontplane 20 including an opposing substrate 201 and a common electrode 202.

Of these, the backplane 10 includes a flat plate-shaped electrode substrate 120, a plurality of pixel electrodes 121 provided on the upper surface of the electrode substrate 120, and an active matrix circuit board 100 provided on the electrode substrate 120. There is. Further, the region of the upper surface of the electrode substrate 120 where the pixel electrodes 121 are provided is particularly referred to as an "image display unit 103", and the region of the image display unit 103 including the pixel electrodes 121 and arranged in a matrix. Is called "pixel 102".

On the other hand, the front plane 20 contains a flat plate-shaped opposed substrate 201, a common electrode 202 provided on the lower surface of the opposed substrate 201, and a dispersion liquid 70 provided below the common electrode 202 and containing particles 71 and a dispersion medium 72. It includes a filled electrophoresis material layer 7 (electro-optical material layer).

Further, the front plane 20 includes a partition wall 91 that separates the electrode substrate 120 and the common electrode 202 and separates the pixels 102 from each other, and a sealing portion 92 that seals the outer edge side of the partition wall 91. There is.

Therefore, the electrophoresis display device 1 (display device) has an active matrix circuit board 100 and an electrophoresis material layer 7 (electro-optical material layer) provided between the pixel electrode 121 and the common electrode 202. ..

Hereinafter, the configuration of each part will be described in sequence.
The electrode substrate 120 and the opposing substrate 201 are sheet-shaped (flat plate-shaped) members, respectively. These may be either flexible or rigid.

Examples of the constituent materials of the electrode substrate 120 and the opposing substrate 201 include various resin materials and various glass materials. Of these, the opposing substrate 201 is made of a particularly translucent material. As a result, the upper surface of the facing substrate 201 shown in FIG. 1 becomes the display surface.

In addition to the pixel electrode 121 and the common electrode 202, the elements and wiring included in the circuit are made of a conductive material. Examples of the conductive material include various metal materials such as Al and Cu, various conductive polymer materials, and various conductive oxidations such as ITO (indium tin oxide) and IZO (indium zinc oxide). Materials and the like can be mentioned. Of these, the common electrode 202 is made of a particularly translucent material.

Further, examples of the constituent materials of the partition wall 91 and the sealing portion 92 include various resin materials. The partition wall 91 may be provided as needed or may be omitted.

The dispersion liquid 70 contains the particles 71 and the dispersion medium 72.
In the present embodiment, an example will be described in which the particles 71 include two types of negatively charged black particles 71a and positively charged white particles 71b, and the dispersion medium 72 is transparent. That is, the dispersion liquid 70 according to the present embodiment is formed by dispersing black particles 71a and white particles 71b in a transparent dispersion medium 72. In the following description, the particle 71 refers to both black particles 71a and white particles 71b.

The configuration of the dispersion liquid 70 is not limited to the above. For example, the color exhibited by the particles 71 is not particularly limited, and may be a color other than black or white. Further, the particle 71 may be composed of only one kind of particles, or may contain three or more kinds of particles having different colors.

Further, when the particles 71 are composed of one kind of particles, the dispersion medium 72 may have a color different from that of the particles 71. In this case, the color exhibited by the particles 71 is not particularly limited. For example, when the dispersion medium 72 is light or white, it is preferably dark or black, and conversely, the dispersion medium 72 is dark. Alternatively, when it is black, it is preferably light or white.

Such a dispersion liquid 70 is filled in the vesicle portion (the portion corresponding to the pixel 102 described above) separated and formed by the partition wall 91 described above, and constitutes a part of the electrophoresis material layer 7.

Examples of the particles 71 include oxide-based particles such as titanium oxide, zinc oxide, iron oxide, chromium oxide, and zirconium oxide, nitride-based particles such as silicon nitride and titanium nitride, and sulfide-based particles such as zinc sulfide. Boride-based particles such as titanium borodate, inorganic pigment particles such as strontium chromate, cobalt aluminate, subchromium copper, and ultramarin, organic pigment particles such as azo-based, quinacridone-based, anthraquinone-based, dioxazine-based, and perylene-based, etc. Can be used. Further, composite particles in which a pigment is applied to the surface of resin particles composed of acrylic resin, urethane resin, urea resin, epoxy resin, polystyrene, polyester or the like can also be used.
Further, the surface of the above-mentioned particles may be subjected to various surface treatments.

The dispersion medium 72 is not particularly limited, but for example, a liquid having a boiling point of 100 ° C. or higher and high insulating properties is preferably used. Specifically, for example, various waters, alcohols such as butanol and glycerin, cellosolves such as butyl cellosolve, esters such as butyl acetate, ketones such as dibutylketone, and aliphatic hydrocarbons such as pentane (liquid paraffin), Aliphatic hydrocarbons such as cyclohexane, aromatic hydrocarbons such as xylene, halogenated hydrocarbons such as methylene chloride, aromatic heterocycles such as pyridine, nitriles such as acetonitrile, N, N-dimethylformamide Examples thereof include amides such as, carboxylates, silicone oils and various other oils, and these can be used alone or as a mixture.

A plurality of microcapsules may be arranged between the electrode substrate 120 and the common electrode 202 without forming the partition wall 91, and the dispersion liquid 70 may be sealed in the microcapsules. That is, the electrophoretic substance layer 7 may be formed by arranging the microcapsules in a sheet shape.

Examples of the constituent materials of the microcapsules include gelatin, a composite material of arabic rubber and gelatin, urethane resin, melamine resin, urea resin, epoxy resin, phenol resin, acrylic resin, urethane resin, and olefin. Examples thereof include various resin materials such as based resins, polyamides, and polyethers, and one or a combination of two or more of these can be used.

<Active matrix circuit board>
Next, the active matrix circuit board 100 will be described.

FIG. 2 is a block diagram showing the active matrix circuit board and common electrodes shown in FIG. FIG. 3 is a diagram showing a circuit configuration in one pixel and a common electrode of the active matrix circuit board shown in FIG.

The active matrix circuit board 100 shown in FIGS. 2 and 3 includes an image display unit 103 in which a plurality of pixels 102 are arranged in a matrix, a scanning line drive circuit 106 provided outside the image display unit 103, and data lines. It includes a drive circuit 107, a power supply circuit 119 including a power supply modulation unit 108 and a power supply unit 109, and a control unit 110. Of these, the power supply modulation unit 108 is provided with a common electrode switch circuit 1081, a third switch circuit 1082, and a fourth switch circuit 1083. Further, the power supply unit 109 has a power supply 1091, a first voltage end 1092 that outputs a potential of V (first potential) as an example, and a second voltage terminal 1092 that outputs a potential of 0 [V] (second potential) as an example. A voltage end 1093 is provided.

In the image display unit 103, a plurality of scanning lines 104 (scan) extend in the X-axis direction. On the other hand, in the image display unit 103, a plurality of data lines 105 (data) extend in the Y-axis direction. Pixels 102 are provided in the vicinity of the intersection of the scanning line 104 and the data line 105, respectively.

Further, as wiring common to all pixels 102, the first power supply line 111 (L1), the second power supply line 112 (L2), the third power supply line 113 (L3), and the fifth power supply line 115 (Vss). And have.

Further, as an electrode common to all the pixels 102, the common electrode 202 shown in FIG. 3 is provided.

The pixels 102 shown in FIG. 3 include a driving TFT 124 (pixel switching element), a memory circuit 125, a first switch circuit 126, a second switch circuit 127, a pixel electrode 121, a pixel electrode 121, and a common electrode 202. An electrophoretic material layer 7 provided between the two is provided. These are provided corresponding to the individual pixels 102. The TFT is a Thin Film Transistor.

Here, the wiring provided in the pixel 102 will be described.
As shown in FIG. 3, the pixel 102 includes a scanning line 104 (scan), a data line 105 (data), a first power supply line 111 (L1), a second power supply line 112 (L2), and a third power supply line 113 ( L3) and the fifth power supply line 115 (Vss) are arranged.

Of these, the scanning line 104 supplies a selection signal that defines the on-timing of the driving TFT 124.

Further, the data line 105 supplies an image signal that defines 1-bit image data.
In the present embodiment, when "L" (first state) is defined as image data, a low level (low potential) image signal is supplied, and "H" (second state) is defined as image data. In this case, a high level (high potential) image signal shall be supplied.

That is, the active matrix circuit board 100 is a drive TFT 124 (which is provided between the scanning line 104, the data line 105, the scanning line 104, the data line 105, and the memory circuit 125, which is provided corresponding to the pixel 102. Pixel switching element) and. As a result, it is possible to operate so as to input the image data based on the image signal supplied from the data line 105 into the memory circuit 125.

Further, the first power supply line 111 supplies a drive signal for running the particles 71 to the pixel electrode 121 via the first switch circuit 126.

On the other hand, the second power supply line 112 supplies a drive signal for running the particles 71 to the pixel electrode 121 via the second switch circuit 127.

In the present embodiment, as an example, the potential of V as the drive signal Vpix (L1) from the first power supply line 111 (first potential) is 0 [from the second power supply line 112 as the drive signal Vpix (L2). It is assumed that the potentials of V] (second potentials) are supplied respectively.

Further, the third power supply line 113 is connected to the common electrode 202, and supplies the common potential signal Vcom to the common electrode 202.

In the present embodiment, as an example, a common potential signal Vcom of a pulse waveform composed of two potentials of V (first potential) and 0 [V] (second potential) is supplied from the third power supply line 113. Shall be. In other words, the lower potential of the binary potentials supplied to the third power supply line 113 is set as the reference potential, that is, 0 [V].

The potential of V supplied to the first power supply line 111 and the third power supply line 113 is not particularly limited, but is generally set to about 5 V or more and 20 V or less.

Further, the fifth power supply line 115 supplies a constant potential potential signal to the memory circuit 125. As a result, the image signal can be held in the memory circuit 125.

The potential supplied to the fifth power supply line 115 is not particularly limited, but is generally 0 [V].

The common electrode 202 is connected to the third power supply line 113 as described above. The electrophoresis display device 1 has an electrophoresis substance layer 7 provided between the pixel electrode 121 and the common electrode 202.

The electrophoresis material layer 7 is sandwiched between the pixel electrode 121 and the common electrode 202, and the particles 71 are run by the electric field associated with the potential difference generated between them, and an image is displayed on the display surface. That is, the migration direction of the charged particles 71 is determined according to the polarity of the electric charge and the direction of the electric field of the particles 71. For example, if the potential of the pixel electrode 121 is set to be higher than the potential of the common electrode 202, an electric field is generated from the pixel electrode 121 toward the common electrode 202, so that the positively charged white particles 71b are the common electrode 202. The black particles 71a that migrate to the side and are negatively charged migrate to the pixel electrode 121 side. In the present embodiment, since the display surface is set on the opposite substrate 201 side, white is displayed on the display surface by such migration of the particles 71. On the other hand, if the potential of the pixel electrode 121 is set to be lower than the potential of the common electrode 202, an electric field is generated from the common electrode 202 toward the pixel electrode 121, so that the positively charged white particles 71b are the pixel electrodes 121. The black particles 71a that migrate to the side and are negatively charged migrate to the common electrode 202 side. As a result, black is displayed on the display surface.

Next, the circuit and the like provided in the pixel 102 will be described.
The driving TFT 124 is, for example, an N-type MOS (Metal Oxide Semiconductor) transistor. The gate electrode of the driving TFT 124 is connected to the scanning line 104, the source electrode is connected to the data line 105, and the drain electrode is connected to the input terminal of the memory circuit 125.

The memory circuit 125 includes a capacitor 1251 provided between the drain electrode of the driving TFT 124 and the fifth power supply line 115.

The memory circuit 125 according to the present embodiment is a DRAM (Dynamic Random Access Memory) type memory circuit, which is a memory circuit having one input and one output capable of holding 1-bit image data. The retained image data is supplied to the common input terminal P1 of the first switch circuit 126 and the second switch circuit 127.

The first switch circuit 126 includes a P-type MOS transistor 1261. Specifically, the source electrode of the P-type MOS transistor 1261 is connected to the first power supply line 111, the drain electrode is connected to the common output terminal P2 of the first switch circuit 126 and the second switch circuit 127, and the gate electrode is common. It is connected to the input terminal P1.

The second switch circuit 127 includes an N-type MOS transistor 1271. Specifically, the source electrode of the N-type MOS transistor 1271 is connected to the second power supply line 112, the drain electrode is connected to the common output terminal P2, and the gate electrode is connected to the common input terminal P1.

As described above, the pixel electrode 121 is connected to the common output terminal P2. As a result, the drive signal is supplied to the pixel electrode 121 via the common output terminal P2.

Next, a circuit and the like provided outside the image display unit 103 will be described.
The scanning line drive circuit 106 is connected to a plurality of scanning lines 104, and supplies a selection signal defining the on-timing of the driving TFT 124 to the gate electrode of the driving TFT 124 via the scanning line 104.

Further, the data line drive circuit 107 is connected to a plurality of data lines 105, and supplies an image signal defining 1-bit image data to the source electrode of the drive TFT 124 via the data line 105.

Further, the power supply modulation unit 108 is connected to the first power supply line 111, the second power supply line 112, the third power supply line 113, and the fifth power supply line 115, and each of these wirings and the power supply unit 109 are electrically connected. Connect and disconnect to. That is, the power supply unit 109 is connected to the power supply modulation unit 108 as shown in FIG. As a result, the electrical connection between the power supply unit 109 and these power supply lines is controlled by the power supply modulation unit 108.

Here, on the right side of the pixel 102 in FIG. 3, the first power supply line 111, the second power supply line 112, the third power supply line 113, and the power supply unit 109 included in the power supply modulation unit 108 are electrically opened and closed. The circuit to be used is selectively illustrated. As shown in FIG. 3, the power supply modulation unit 108 includes a common electrode switch circuit 1081 (SWcom), a third switch circuit 1082 (SW3), and a fourth switch circuit 1083 (SW4). Then, the first power supply line 111, the second power supply line 112, and the third power supply line 113 are electrically connected to the power supply unit 109 by the common electrode switch circuit 1081, the third switch circuit 1082, and the fourth switch circuit 1083. Connected and disconnected.

Of these, the common electrode switch circuit 1081 includes a one-circuit, two-contact type switch, and as shown in FIG. 3, the connection destination of the third power supply line 113 can be switched between the contact 1081a and the contact 1081b. Further, the contact 1081a is connected to the third switch circuit 1082 and the first voltage end 1092. On the other hand, the contact 1081b is connected to the fourth switch circuit 1083 and the second voltage end 1093.

When the third power supply line 113 and the contact 1081a are connected by the operation of the common electrode switch circuit 1081, the positive electrode of the power supply 1091 and the common electrode 202 are electrically connected. On the other hand, when the third power supply line 113 and the contact 1081b are connected by the operation of the common electrode switch circuit 1081, the negative electrode of the power supply 1091 and the common electrode 202 are electrically connected.

The common electrode switch circuit 1081 operates so as to alternately switch between a period in which the third power supply line 113 is connected to the contact 1081a and a period in which the third power supply line 113 is connected to the contact 1081b. That is, in the common electrode switch circuit 1081, the third power supply line 113 alternately conducts to either the first voltage end 1092 or the second voltage end 1093. As a result, the potential of V (first potential) and the potential of 0 [V] (second potential) are alternately supplied to the common electrode 202.

The third switch circuit 1082 includes a one-circuit, one-contact type switch, and electrically opens and closes between the first power supply line 111 and the first voltage end 1092 of the power supply unit 109, as shown in FIG. By opening and closing the third switch circuit 1082, the state in which the potential of V (first potential) is supplied to the first switch circuit 126 and the state in which the first power supply line 111 is electrically floating (float state) are switched. be able to.

Then, the third switch circuit 1082 operates in cooperation with the common electrode switch circuit 1081. Specifically, when the third power supply line 113 is conducting with the second voltage end 1093 in the common electrode switch circuit 1081, the third power supply line 111 and the first voltage end 1092 are connected in the third switch circuit 1082. When the third power supply line 113 is conducting with the first voltage end 1092 in the common electrode switch circuit 1081, the third power supply line 111 and the first voltage end 1092 are cut off in the third switch circuit 1082. ..

The fourth switch circuit 1083 includes a one-circuit, one-contact type switch, and electrically opens and closes between the second power supply line 112 and the second voltage end 1093 of the power supply unit 109, as shown in FIG. By opening and closing the fourth switch circuit 1083, the state of supplying 0 potential (second potential) to the second switch circuit 127 and the state of electrically floating the second power supply line 112 (float state) are switched. be able to.

Then, the fourth switch circuit 1083 operates in cooperation with the common electrode switch circuit 1081. Specifically, when the third power supply line 113 is conducting with the first voltage end 1092 in the common electrode switch circuit 1081, between the second power supply line 112 and the second voltage end 1093 in the fourth switch circuit 1083. When the third power supply line 113 is conducting with the second voltage end 1093 in the common electrode switch circuit 1081, the fourth power supply line 112 and the second voltage end 1093 are cut off in the fourth switch circuit 1083. ..

The operations of the scanning line drive circuit 106, the data line drive circuit 107, and the power supply modulation unit 108 are controlled by the control unit 110, respectively. Specifically, the control unit 110 controls the operations of the scanning line drive circuit 106, the data line drive circuit 107, and the power supply modulation unit 108 based on a signal input from an external higher-level control device (not shown).

Further, as described above, the power supply unit 109 outputs the power supply 1091, the first voltage end 1092 that outputs the potential of V (first potential), and the second power supply unit 109 that outputs the potential of 0 [V] (second potential). It includes a voltage end 1093 and.

<How to drive the display device>
Next, the first embodiment of the driving method of the display device of this invention will be described. Hereinafter, the driving method of the electrophoresis display device 1 shown in FIGS. 1 to 3 will be described.

The electrophoresis display device 1 shown in FIGS. 1 to 3 includes an electrode substrate 120 (board), a first power supply line 111, a second power supply line 112, a third power supply line 113, a power supply unit 109, a pixel electrode 121, and the like. It has a memory circuit 125, a common electrode 202, a first switch circuit 126, and a second switch circuit 127.

The driving method of the electrophoresis display device 1 according to the present embodiment is either between the first power supply line 111 and the third power supply line 113 or between the second power supply line 112 and the third power supply line 113. It has a first step of applying a potential difference and a second step of electrically floating the first power supply line 111 and the second power supply line 112. Hereinafter, each step will be described in sequence.

In the first step, in rewriting the display, first, the driving TFT 124 is turned on and the image signal is supplied from the data line 105. As a result, the image data is held in the memory circuit 125.
Then, when the image data held in the memory circuit 125 is input to the first switch circuit 126 and the second switch circuit 127, the first switch circuit 126 and the second switch circuit 127 behave differently from each other.

For example, when the image data output from the memory circuit 125 to the common input terminal P1 is “L”, the first switch circuit 126 is in a conductive state. On the other hand, when the output image data is "H", the first switch circuit 126 is in the cutoff state.
Further, when the image data output from the memory circuit 125 to the common input terminal P1 is "H", the second switch circuit 127 is in a conductive state. On the other hand, when the output image data is "L", the second switch circuit 127 is in the cutoff state.

Therefore, hereinafter, the case will be described separately depending on whether the image data is “L” (first state) or “H” (second state).

First, the case where the image data is "L" will be described.
FIG. 4 is a timing chart showing a driving method of the display device including the active matrix circuit board 100 shown in FIG. 3 when the image data is “L” (first state).

First, as shown in FIG. 4, a common potential signal Vcom of a pulse waveform composed of binary potentials of 0 [V] and V is supplied to the common electrode 202. Specifically, the potential of 0 [V] is supplied in the period T1, the potential of V is supplied in the period T2, and the potential of 0 [V] is supplied again in the period T3.
Such a potential supply pattern is formed by the operation of the common electrode switch circuit 1081 shown in FIG. That is, in the period T1 and the period T3, the third power supply line 113 is connected to the contact 1081b, and in the period T2, the third power supply line 113 is connected to the contact 1081a. As a result, the common potential signal Vcom of the pulse waveform shown in FIG. 4 is formed.

When the image data is "L", the second switch circuit 127 is in the cutoff state, so that the first switch circuit 126 is in the conductive state. As a result, the common output terminal P2 becomes conductive with the first power supply line 111.

Further, as described above, the third switch circuit 1082 operates in cooperation with the common electrode switch circuit 1081. Specifically, when the third power supply line 113 is conducting with the second voltage end 1093 in the common electrode switch circuit 1081, that is, when the period T1 is reached, the third power supply circuit 1082 is turned on and the first power supply line is turned on. It conducts between 111 and the first voltage end 1092.

As a result, the potential V is as shown in FIG. 4 from the first voltage end 1092 to the pixel electrode 121 via the third switch circuit 1082, the first power supply line 111, the first switch circuit 126, and the common output terminal P2. Drive signal Vpix (L1) is supplied.

Since the potential of the common electrode 202 is 0 [V] in the period T1, a potential difference Vpix (L1) -Vcom having a magnitude V is applied between the pixel electrode 121 and the common electrode 202 (first step). The particles 71 contained in the electrophoresis material layer 7 migrate according to the electric field generated by the potential difference Vpix (L1) -Vcom.

On the other hand, the configuration in which the electrophoretic substance layer 7 is interposed between the pixel electrode 121 and the common electrode 202 can be regarded as a capacitor having the electrophoretic substance layer 7 as a dielectric. Therefore, in the period T1, the electrophoretic substance layer 7 is charged with the pixel electrode 121 and the common electrode 202 as terminals. In other words, in the first step, charging is performed between the first power supply line 111 and the third power supply line 113.

Next, the connection destination of the common electrode switch circuit 1081 is switched with the transition from the period T1 to the period T2. As a result, the common potential signal Vcom changes from 0 [V] to V.

At the same time, the third switch circuit 1082 is operated in cooperation with the common electrode switch circuit 1081. Specifically, when the third power supply line 113 is conducting with the first voltage end 1092 in the common electrode switch circuit 1081, that is, during the period T2, the third power supply circuit 1082 is turned off and the first power supply line 111 and the like. The circuit with the first voltage end 1092 is cut off.

As a result, the first power supply line 111 is in an electrically floating state (float state) (second step). At this time, the electric charge charged in the electrophoresis material layer 7 in the period T1 contributes to the migration of the particles 71. Therefore, even during the period T2 in which the voltage is not directly applied from the power supply unit 109, an electric field is generated between the pixel electrode 121 and the common electrode 202 by the discharge of the electric charge charged in the first step, and the particles 71 are generated. It can be run (rewrite the display). Therefore, the migration distance of the particles 71 can be made longer than before by the amount of migration during the period T2. That is, it is possible to increase the migration speed (display rewriting speed) as compared with the conventional case.

At this time, the electrophoretic substance layer 7 located in the pixel 102 whose image data is "L" is charged and discharged. Therefore, the voltage immediately after the charge charged in the electrophoresis material layer 7 is discharged (the initial voltage α of the drive signal Vpix (L1) shown in FIG. 4) is obtained by the following equation.
_{α = VC all / (C all} + C pra)

Here, _Call is the total capacity of the electrophoresis material layer 7 located at the pixel 102 whose image data is “L”. Further, C _pr is a parasitic capacitance of the first power supply line 111 and wiring at an equipotential potential with the first power supply line 111.

As is clear from the above equation, the more pixels 102 whose image data is "L" and the smaller the parasitic capacitance of the first power supply line 111 or the like, the higher the initial voltage α. The potential difference associated with the drive signal Vpix (L1) gradually decreases as the electric charge is discharged.

The third switch circuit 1082 operates in cooperation with the common electrode switch circuit 1081, but the cooperation at this time may be simultaneous or may be slightly different. In the latter case, the third switch circuit 1082 may be cut off immediately before the common potential signal Vcom supplied to the third power supply line 113 changes from 0 [V] to V. The amount of time lag at this time is not particularly limited, but as an example, about 1/1000 or more and 1/10 or less of the half cycle of the pulse waveform of the common potential signal Vcom can be mentioned.

Next, the transition to the period T3 occurs, but in the period T3, the behavior is the same as that of the period T1 described above. Therefore, the third switch circuit 1082 is turned on again, and the first power supply line 111 and the first voltage end 1092 are connected to each other. Conduct between.

As a result, the potential V is as shown in FIG. 4 from the first voltage end 1092 to the pixel electrode 121 via the third switch circuit 1082, the first power supply line 111, the first switch circuit 126, and the common output terminal P2. Drive signal Vpix (L1) is supplied. After that, the behavior of the period T2 and the behavior of the period T3 are repeated.

By going through the first step and the second step as described above, the migration of the particles 71 is not delayed for a longer period of time, so that the migration speed (display rewriting speed) can be increased.

Next, a case where the image data is “H” will be described.
FIG. 5 is a timing chart showing a driving method of the display device including the active matrix circuit board 100 shown in FIG. 3 when the image data is “H” (second state).

First, as shown in FIG. 5, a common potential signal Vcom of a pulse waveform composed of binary potentials of 0 [V] and V is supplied to the common electrode 202. Specifically, the potential of V is supplied in the period T1, the potential of 0 [V] is supplied in the period T2, and the potential of V is supplied again in the period T3. In FIG. 5, for convenience of explanation, the relationship between the periods T1 to T3 and the common potential signal Vcom is shifted by half a wavelength of the pulse waveform with respect to FIG.

When the image data is "H", the first switch circuit 126 is in the cutoff state, so that the second switch circuit 127 is in the conductive state. As a result, the common output terminal P2 becomes conductive with the second power supply line 112.

Further, the fourth switch circuit 1083 operates in cooperation with the common electrode switch circuit 1081 as described above. Specifically, when the third power supply line 113 is conducting with the first voltage end 1092 in the common electrode switch circuit 1081, that is, when the period T1 is reached, the fourth power supply circuit 1083 is turned on and the second power supply line is turned on. Conducts between 112 and the second voltage end 1093.

As a result, the potential is 0 with respect to the pixel electrode 121 from the second voltage end 1093 via the fourth switch circuit 1083, the second power supply line 112, the second switch circuit 127, and the common output terminal P2, as shown in FIG. The drive signal Vpix (L2) of [V] is supplied.

In the period T1, since the potential of the common electrode 202 is V, the potential of the pixel electrode 121 is −V with respect to the potential of the common electrode 202, and the potential difference Vpix of magnitude V between the pixel electrode 121 and the common electrode 202. (L2) -Vcom is applied (first step). The particles 71 contained in the electrophoresis material layer 7 migrate according to the electric field generated by the potential difference Vpix (L2) -Vcom.

On the other hand, in the period T1, the electrophoretic substance layer 7 is charged with the pixel electrode 121 and the common electrode 202 as terminals.

Next, the connection destination of the common electrode switch circuit 1081 is switched with the transition from the period T1 to the period T2. As a result, the common potential signal Vcom changes from V to 0 [V].

At the same time, the fourth switch circuit 1083 is operated in cooperation with the common electrode switch circuit 1081. Specifically, when the third power supply line 113 is conducting with the second voltage end 1093 in the common electrode switch circuit 1081, that is, during the period T2, the fourth power supply circuit 1083 is turned off and the second power supply line 112 is used. The circuit with the second voltage end 1093 is cut off.

During that period, the second power supply line 112 is in an electrically floating state (float state) (second step). At this time, the electric charge charged in the electrophoresis material layer 7 contributes to the migration of the particles 71. Therefore, even during the period T2 in which the voltage is not directly applied from the power supply unit 109, an electric field is generated between the pixel electrode 121 and the common electrode 202 by the discharge of the electric charge charged in the first step, and the particles 71 are generated. It can be run (rewrite the display). Therefore, the migration distance of the particles 71 can be made longer than before by the amount of migration during the period T2. That is, it is possible to increase the migration speed (display rewriting speed) as compared with the conventional case.

At this time, the electrophoretic substance layer 7 located in the pixel 102 whose image data is "H" is charged and discharged. Therefore, the voltage immediately after the charge charged in the electrophoresis material layer 7 is discharged (the initial voltage α of the drive signal Vpix (L2) shown in FIG. 5) is the same as when the image data is “L”. It is calculated by the following formula.
_{α = VC all / (C all} + C pra)

Here, _Call is the total capacity of the electrophoresis material layer 7 located at the pixel 102 whose image data is “H”. Further, C _pr is a parasitic capacitance of the second power supply line 112 and wiring equipotential with the second power supply line 112.

As is clear from the above equation, the more pixels 102 whose image data is "H" and the smaller the parasitic capacitance of the second power supply line 112 or the like, the higher the initial voltage α. The potential difference associated with the drive signal Vpix (L2) gradually decreases as the electric charge is discharged.

The fourth switch circuit 1083 operates in cooperation with the common electrode switch circuit 1081, but the cooperation at this time may be simultaneous or may be slightly different. In the latter case, the fourth switch circuit 1083 may be cut off immediately before the common potential signal Vcom supplied to the third power supply line 113 changes from V to 0 [V]. The amount of time lag at this time is not particularly limited, but as an example, about 1/1000 or more and 1/10 or less of the half cycle of the pulse waveform of the common potential signal Vcom can be mentioned.

Next, the transition to the period T3 occurs, but in the period T3, the behavior is the same as that of the period T1 described above. Therefore, the fourth switch circuit 1083 is turned on again, and the second power supply line 112 and the second voltage end 1093 are connected to each other. Conduct between.

As a result, the potential is 0 with respect to the pixel electrode 121 from the second voltage end 1093 via the fourth switch circuit 1083, the second power supply line 112, the second switch circuit 127, and the common output terminal P2, as shown in FIG. The drive signal Vpix (L2) of [V] is supplied. After that, the behavior of the period T2 and the behavior of the period T3 are repeated.

By going through the first step and the second step as described above, the migration of the particles 71 is not delayed for a longer period of time, so that the migration speed (display rewriting speed) can be increased.

As described above, according to the present embodiment, it is possible to maintain a potential difference larger than zero between the pixel electrode 121 and the common electrode 202. As a result, the period during which the particles 71 do not run can be substantially eliminated or reduced. As a result, the time required for migration of the particles 71 can be shortened without increasing the voltage applied between the pixel electrode 121 and the common electrode 202, and the display can be rewritten in a shorter time (the migration speed of the particles 71). An electrophoresis display device 1 (which has been speeded up) can be obtained. On the contrary, the voltage applied between the pixel electrode 121 and the common electrode 202 can be reduced without lengthening the time required for rewriting the display, and the power consumption of the electrophoresis display device 1 can be suppressed. ..

Further, according to the present embodiment, it is a relatively simple configuration in which the supply of potential to the first power supply line 111, the second power supply line 112, and the third power supply line 113 common to each pixel 102 is modulated in a coordinated manner. The above effects can be obtained. Therefore, it is possible to achieve both low cost and high density of the active matrix circuit board 100 while achieving high speed and low power consumption for display rewriting.

Of the black particles 71a and the white particles 71b, the migration speed of one may be sufficiently high, while the migration speed of the other may be insufficient. In such a case, it is sufficient to "substantially eliminate the period during which the particles 71 do not migrate" only when displaying the particles 71 having a low migration rate.

Therefore, either one of the above-mentioned third switch circuit 1082 and the fourth switch circuit 1083 may be omitted. For example, when the migration speed of the white particles 71b is slow, the speed of rewriting the display may be increased only when the white particles 71b are attracted to the common electrode 202 side to display white. Therefore, in that case, if the fourth switch circuit 1083 is omitted and only the third switch circuit 1082 is provided, the migration speed when the white particles 71b are migrated to the common electrode 202 side can be further increased. be able to. As a result, even if the fourth switch circuit 1083 is omitted, the migration speed of both the black particles 71a and the white particles 71b can be increased. Therefore, the structure of the active matrix circuit board 100 can be simplified while increasing the migration speed.

Summarizing the above, the electrophoresis display device 1 according to the present embodiment includes an electrode substrate 120 (board) including an image display unit 103 including pixels 102, a first power supply line 111, a second power supply line 112, and a third power supply. The line 113, the pixel electrode 121 provided corresponding to the pixel 102, and any of "L" (first state) and "H" (second state) provided as image data corresponding to the pixel 102. The memory circuit 125 that can hold and output the voltage, the common electrode 202 that is connected to the third power supply line 113, and the first voltage end 1092 and the first potential that output the V potential (first potential) are different. Between the power supply unit 109 having the second voltage end 1093 that outputs a potential of 0 [V] (second potential) and any of the third power supply line 113, the first voltage end 1092, and the second voltage end 1093. The common electrode switch circuit 1081 that conducts alternately is provided between the first power supply line 111 and the pixel electrode 121, and when the output from the memory circuit 125 is "L", it conducts and the output from the memory circuit 125 becomes conductive. The first switch circuit 126 that shuts off when it is "H" is provided between the second power supply line 112 and the pixel electrode 121, and when the output from the memory circuit 125 is "H", it conducts and becomes conductive, and the memory circuit 125 Between the second switch circuit 127 that shuts off when the output from is "L" and the first power supply line 111 and the first voltage end 1092 when the third power supply line 113 is conducting with the second voltage end 1093. A third switch circuit 1082 is provided, which cuts off between the first power supply line 111 and the first voltage end 1092 when the third power supply line 113 is conducting with the first voltage end 1092.

The electrophoresis display device 1 according to the present embodiment has an electrophoresis substance layer 7 (electro-optical substance layer) provided between the pixel electrode 121 and the common electrode 202.

According to the present embodiment as described above, as described above, the time required for migration of the particles 71 can be shortened without increasing the voltage applied between the pixel electrode 121 and the common electrode 202, and the display can be rewritten more. An electrophoresis display device 1 that can be performed in a short time (the migration speed of the particles 71 is increased) can be obtained. On the contrary, the voltage applied between the pixel electrode 121 and the common electrode 202 can be reduced without lengthening the time required for rewriting the display, and the power consumption of the electrophoresis display device 1 can be suppressed. ..

Further, in the electrophoresis display device 1 according to the present embodiment, when the third power supply line 113 is conducting with the first voltage end 1092, the second power supply line 112 and the second voltage end 1093 are conducted with each other. The third power supply line 113 further includes a fourth switch circuit 1083 that cuts off between the second power supply line 112 and the second voltage end 1093 when the power supply line 113 is conducting with the second voltage end 1093.

As a result, the above effect can be achieved regardless of the displayed content. That is, the time required for migration of the particles 71 can be shortened and the display can be rewritten in a shorter time without increasing the voltage applied between the pixel electrode 121 and the common electrode 202 (high migration speed of the particles 71). An electrophoresis display device 1 capable of enjoying the effect of (having been achieved) regardless of the display content can be obtained.

(Modification example)
Here, a modified example of the above embodiment will be described.
FIG. 6 is a diagram showing a modified example in which a part of the circuit configuration shown in FIG. 3 is deformed. In the following description, for convenience of explanation, the same reference numerals are given to the same configurations as those in the above embodiment.
This modification is the same as that of the above embodiment except that the configuration of the power supply circuit is different.

In the above embodiment, in the common electrode switch circuit 1081 (SWcom) included in the power supply modulation unit 108, the connection destination of the third power supply line 113 is switched between the first voltage end 1092 and the second voltage end 1093. ing. That is, both the first power supply line 111 and the third power supply line 113 can be connected to the first voltage end 1092, while the second power supply line 112 and the second power supply line 112 and the second power supply line 112 can be connected to the second voltage end 1093. Both of the three power supply lines 113 can be connected.

However, the potential supplied to the first power supply line 111 and the potential supplied to the third power supply line 113 do not necessarily have to be supplied from the same voltage end, but are supplied from different voltage ends. You may be. That is, in the above embodiment, the potential of V (first potential) is output from the first voltage end 1092 to both the first power supply line 111 and the third power supply line 113, and the potential of 0 [V] (second potential). Is output from the second voltage end 1093 to both the second power supply line 112 and the third power supply line 113, but the present invention is not limited to this configuration, and the third power supply line 113 has a different voltage. The electric potential may be supplied from the end.

That is, the power supply unit 109 according to this modification also includes another power supply 1094 different from the power supply 1091. From this power supply 1094, a common potential signal Vcom of a pulse waveform composed of two potentials of V (third potential) and 0 [V] (fourth potential) is supplied to the third power supply line 113. There is. In other words, the power supply unit 109 is individually prepared with a power supply 1091 that supplies the first and second potentials and a power supply 1094 that supplies the third and fourth potentials. Even in such a modified example, the same effect as that of the above embodiment can be obtained.
In this case, the third potential is higher than the fourth potential. That is, the high-low relationship between the third potential and the fourth potential is the same as the high-low relationship between the first potential and the second potential.

Therefore, the third switch circuit 1082 according to the present modification conducts between the first power supply line 111 and the power supply unit 109 when the fourth potential is supplied to the third power supply line 113, and the third power supply line occurs. When the third potential is supplied to 113, it is configured to cut off between the first power supply line 111 and the power supply unit 109. That is, the electrophoresis display device 1 according to this modification has such a third switch circuit 1082.

Summarizing the above, the electrophoretic display device according to the present modification includes an electrode substrate 120 (substrate) including an image display unit 103 including pixels 102, and a first power supply line 111, a second power supply line 112, and a third power supply line. A power source that outputs 113, a first potential, a second potential different from the first potential, and a third potential and a fourth potential having the same high-low relationship as the high-low relationship between the first potential and the second potential. Power supply modulation that supplies the first potential to the unit 109 and the first power supply line 111, supplies the second potential to the second power supply line 112, and alternately supplies the third potential and the fourth potential to the third power supply line 113. The unit 108, the pixel electrode 121 provided corresponding to the pixel 102, and any of "L" (first state) and "H" (second state) provided as image data corresponding to the pixel 102. The output from the memory circuit 125 is provided between the memory circuit 125 capable of holding and outputting the voltage, the common electrode 202 connected to the third power supply line 113, and the first power supply line 111 and the pixel electrode 121. The memory circuit 125 is provided between the first switch circuit 126, the second power supply line 112, and the pixel electrode 121, which conducts when in the first state and cuts off when the output from the memory circuit 125 is in the second state. The power supply modulation unit 108 includes a second switch circuit 127 that conducts when the output from the memory circuit 125 is in the second state and shuts off when the output from the memory circuit 125 is in the first state, and the power supply modulation unit 108 has a third power supply line 113. Conducts between the first power supply line 111 and the power supply unit 109 when the fourth potential is supplied to the third power supply line 113, and when the third potential is supplied to the third power supply line 113, the first power supply line 111 and the power supply unit 109 It is provided with a third switch circuit 1082 that cuts off the potential between the two.

As a result, the electrophoresis display device according to the present modification has the same effect as that of the above embodiment, that is, the time required for the electrophoresis of the particles 71 without increasing the voltage applied between the pixel electrode 121 and the common electrode 202. The effect is that the electrophoresis display device 1 can be obtained in which the display can be rewritten in a shorter time (the migration speed of the particles 71 is increased).

Further, when the third potential is supplied to the third power supply line 113, the fourth switch circuit 1083 conducts between the second power supply line 112 and the power supply unit 109, and the fourth potential is connected to the third power supply line 113. Is supplied, it is configured to cut off between the second power supply line 112 and the power supply unit 109. That is, the electrophoresis display device according to this modification has such a fourth switch circuit 1083. As a result, the electrophoresis display device 1 has the same effect as that of the above embodiment, that is, the time required for the electrophoresis of the particles 71 is shortened without increasing the voltage applied between the pixel electrode 121 and the common electrode 202. This has the effect of obtaining the electrophoresis display device 1 that can rewrite the display in a shorter time (the migration speed of the particles 71 is increased).

<< Second Embodiment >>
Next, the second embodiment of the present invention will be described.

FIG. 7 is a diagram showing a circuit configuration in one pixel and a common electrode of the active matrix circuit board included in the second embodiment of the display device of the present invention.

Hereinafter, the second embodiment will be described, but in the following description, the differences from the first embodiment will be mainly described, and the description of the same matters will be omitted. The same reference numerals are given to the same configurations as those of the first embodiment described above.

The active matrix circuit board 100 according to the present embodiment is the same as that of the first embodiment except that the first capacitor 131 and the second capacitor 132 are provided.

First, the active matrix circuit board 100 has a first capacitor 131 provided between the first power supply line 111 and the third power supply line 113.

By providing such a first capacitor 131, the first capacitor 131 can be charged while a potential difference is formed between the first power supply line 111 and the third power supply line 113. Therefore, even when the electric capacity of the electrophoretic substance layer 7 is not large, sufficient electric energy can be stored in the first capacitor 131 instead. As a result, the particles 71 can be more reliably migrated even during the period when the voltage is not directly applied from the power supply unit 109, and the migration (rewriting of the display) is faster than that of the first embodiment. Can be done.

On the other hand, the active matrix circuit board 100 has a second capacitor 132 provided between the second power supply line 112 and the third power supply line 113.

By providing such a second capacitor 132, the second capacitor 132 can be charged while a potential difference is formed between the second power supply line 112 and the third power supply line 113. Therefore, even when the electric capacity of the electrophoretic substance layer 7 is not large, sufficient electric energy can be stored in the second capacitor 132 instead. As a result, the particles 71 can be more reliably migrated even during the period when the voltage is not directly applied from the power supply unit 109, and the migration (rewriting of the display) is faster than that of the first embodiment. Can be done.

Further, in the first embodiment, the electrical energy stored in the electrophoresis material layer 7 changes according to the display content of the electrophoresis display device 1. On the other hand, in the present embodiment, a constant electric energy can always be stored in the first capacitor 131 and the second capacitor 132. Therefore, it is also useful from the viewpoint of the stability of the effect.

Next, a method of driving the electrophoresis display device including the active matrix circuit board 100 shown in FIG. 7 will be described.

8 and 9 are timing charts showing a driving method of the display device including the active matrix circuit board shown in FIG. 7, respectively.
Hereinafter, a method of driving the display device including the active matrix circuit board shown in FIG. 7 will be described, but in the following description, the differences from the first embodiment will be mainly described, and the same matters will be omitted. ..

First, the case where the image data is "L" will be described.
FIG. 8 is a timing chart showing a driving method of the display device including the active matrix circuit board 100 shown in FIG. 7 when the image data is “L”.

When the image data is "L", the second switch circuit 127 is in the cutoff state, so that the first switch circuit 126 is in the conductive state. As a result, the common output terminal P2 becomes conductive with the first power supply line 111.

In the period T1, since the potential of the common electrode 202 is 0 [V], a potential difference Vpix (L1) -Vcom having a magnitude V is generated between the pixel electrode 121 and the common electrode 202. The particles 71 contained in the electrophoresis material layer 7 migrate according to the electric field generated by the potential difference Vpix (L1) -Vcom.
On the other hand, in the period T1, the first capacitor 131 is charged.

Next, with the transition from the period T1 to the period T2, the common potential signal Vcom changes from 0 [V] to V.

At the same time, in the period T2, the third switch circuit 1082 is turned off to cut off between the first power supply line 111 and the first voltage end 1092.

As a result, the first power supply line 111 is in an electrically floating state (float state). At this time, the electric charge charged in the first capacitor 131 during the period T1 contributes to the migration of the particles 71. Therefore, even during the period T2 in which the voltage is not directly applied from the power supply unit 109, an electric field can be generated in the electrophoresis material layer 7 to allow the particles 71 to run. Therefore, the migration distance of the particles 71 can be made longer than before by the amount of migration during the period T2. That is, the migration speed can be increased as compared with the conventional case.

At this time, it is the first capacitor 131 provided in all the pixels 102 that is charged. Therefore, immediately after the electric charge charged in the first capacitor 131 is discharged, the drive signal Vpix (L1) of the pixel electrode 121 becomes approximately 2V as shown in FIG. The potential difference associated with the drive signal Vpix (L1) gradually decreases as the electric charge is discharged.

Next, the transition to the period T3 occurs, but in the period T3, the behavior is the same as that of the period T1 described above. Therefore, the third switch circuit 1082 is turned on again, and the first power supply line 111 and the first voltage end 1092 are connected to each other. Conduct between.

As a result, the potential V is as shown in FIG. 8 from the first voltage end 1092 to the pixel electrode 121 via the third switch circuit 1082, the first power supply line 111, the first switch circuit 126, and the common output terminal P2. Drive signal Vpix (L1) is supplied. After that, the behavior of the period T2 and the behavior of the period T3 are repeated.

As described above, since the migration of the particles 71 is not delayed during the entire period, the migration speed can be increased.

Next, the case where the image data is "H" will be described.
FIG. 9 is a timing chart showing a driving method of the display device including the active matrix circuit board 100 shown in FIG. 7 when the image data is “H”. In FIG. 9, for convenience of explanation, the relationship between the periods T1 to T3 and the common potential signal Vcom is shifted by half a wavelength of the pulse waveform with respect to FIG.

When the image data is "H", the first switch circuit 126 is in the cutoff state, so that the second switch circuit 127 is in the conductive state. As a result, the common output terminal P2 becomes conductive with the second power supply line 112.

In the period T1, since the potential of the common electrode 202 is V, a potential difference Vpix (L2) -Vcom having a magnitude V is generated between the pixel electrode 121 and the common electrode 202. The particles 71 contained in the electrophoresis material layer 7 migrate according to the electric field generated by the potential difference Vpix (L2) -Vcom.
On the other hand, in the period T1, the second capacitor 132 is charged.

Next, with the transition from the period T1 to the period T2, the common potential signal Vcom changes from V to 0 [V].

At the same time, in the period T2, the fourth switch circuit 1083 is turned off to cut off between the second power supply line 112 and the second voltage end 1093.

During that period, the second power supply line 112 is in an electrically floating state (float state). At this time, the electric charge charged in the second capacitor 132 during the period T1 contributes to the migration of the particles 71. Therefore, even during the period T2 in which the voltage is not directly applied from the power supply unit 109, an electric field can be generated in the electrophoresis material layer 7 to allow the particles 71 to run. Therefore, the migration distance of the particles 71 can be made longer than before by the amount of migration during the period T2. That is, the migration speed can be increased as compared with the conventional case.

At this time, it is the second capacitor 132 provided in all the pixels 102 that is charged. Therefore, immediately after the electric charge charged in the second capacitor 132 is discharged, the drive signal Vpix (L2) of the pixel electrode 121 becomes substantially −V as shown in FIG. The potential difference associated with the drive signal Vpix (L2) gradually decreases as the electric charge is discharged.

Next, the transition to the period T3 occurs, but in the period T3, the behavior is the same as that of the period T1 described above. Therefore, the fourth switch circuit 1083 is turned on again, and the second power supply line 112 and the second voltage end 1093 are connected to each other. Conduct between.

As a result, the potential is 0 with respect to the pixel electrode 121 from the second voltage end 1093 via the fourth switch circuit 1083, the second power supply line 112, the second switch circuit 127, and the common output terminal P2, as shown in FIG. The drive signal Vpix (L2) of [V] is supplied. After that, the behavior of the period T2 and the behavior of the period T3 are repeated.

As described above, since the migration of the particles 71 is not delayed during the entire period, the migration speed can be increased.
In such a second embodiment, the same effect as that of the first embodiment can be obtained.

<< Third Embodiment >>
Next, a third embodiment of the present invention will be described.

FIG. 10 is a diagram showing a circuit configuration in one pixel and a common electrode of the active matrix circuit board included in the third embodiment of the display device of the present invention.

Hereinafter, the third embodiment will be described, but in the following description, the differences from the first embodiment will be mainly described, and the description of the same matters will be omitted. The same reference numerals are given to the same configurations as those of the first embodiment described above.

The third embodiment is the same as the first embodiment except that the configurations of the memory circuit 125, the first switch circuit 126, and the second switch circuit 127 are different.

The active matrix circuit board 100 according to the present embodiment further has a fourth power supply line 114 (Vdd) as wiring common to all the pixels 102.

The fourth power supply line 114 supplies the potential signal on the high potential side to the memory circuit 125. On the other hand, the fifth power supply line 115 supplies the potential signal on the low potential side to the memory circuit 125. As a result, the memory circuit 125 can be operated.

The potential supplied to the fourth power supply line 114 is not particularly limited, but is generally set to about 5 V or more and 20 V or less, and the potential supplied to the fifth power supply line 115 is not particularly limited, but is generally 0 [V]. ].

The memory circuit 125 according to the present embodiment is a C-MOS (Complementary Metal Oxide Semiconductor) type SRAM (Static Random Access Memory) including two P-type MOS transistors 1252 and 1253 and two N-type MOS transistors 1254 and 1255. ).

Of these, the source electrode of the P-type MOS transistor 1252 is connected to the fourth power supply line 114, and the drain electrode is connected to the drain electrode of the driving TFT 124 and the common input terminal P1 of the first switch circuit 126 and the second switch circuit 127. , The gate electrode is connected to the gate electrode of the N-type MOS transistor 1254. Further, the source electrode of the P-type MOS transistor 1253 is connected to the fourth power supply line 114, the drain electrode is connected to the common input terminal P1'of the first switch circuit 126 and the second switch circuit 127, and the gate electrode is an N-type MOS. It is connected to the gate electrode of transistor 1255.

Further, the source electrode of the N-type MOS transistor 1254 is connected to the fifth power supply line 115, and the drain electrode is connected to the drain electrode of the driving TFT 124 and the common input terminal P1 of the first switch circuit 126 and the second switch circuit 127. The gate electrode is connected to the gate electrode of the P-type MOS transistor 1252. Further, the source electrode of the N-type MOS transistor 1255 is connected to the fifth power supply line 115, the drain electrode is connected to the common input terminal P1'of the first switch circuit 126 and the second switch circuit 127, and the gate electrode is a P-type MOS. It is connected to the gate electrode of transistor 1253.

Further, the drain electrode of the P-type MOS transistor 1252 and the drain electrode of the N-type MOS transistor 1254 are connected to the gate electrode of the P-type MOS transistor 1253 and the gate electrode of the N-type MOS transistor 1255.

Further, the gate electrode of the P-type MOS transistor 1252 and the gate electrode of the N-type MOS transistor 1254 are connected to the drain electrode of the P-type MOS transistor 1253 and the drain electrode of the N-type MOS transistor 1255.

The memory circuit 125 according to the present embodiment is a memory circuit capable of holding 1-bit image data. The retained image data is maintained in the memory circuit 125 even when the driving TFT 124 is cut off. Then, the retained image data is supplied to the common input terminals P1 and P1'of the first switch circuit 126 and the second switch circuit 127.

The first switch circuit 126 and the second switch circuit 127 according to the present embodiment are each composed of a transfer gate.
Specifically, the first switch circuit 126 includes a P-type MOS transistor 126a and an N-type MOS transistor 126b.

Of these, the source electrode of the P-type MOS transistor 126a is connected to the first power supply line 111, the drain electrode is connected to the pixel electrode 121 via the common output terminal P2, and the gate electrode is the drain electrode of the driving TFT 124 and the first It is connected to the common input terminal P1 of the switch circuit 126 and the second switch circuit 127.

Further, the source electrode of the N-type MOS transistor 126b is connected to the first power supply line 111, the drain electrode is connected to the pixel electrode 121 via the common output terminal P2, and the gate electrode is connected to the common input terminal P1'. ..

On the other hand, the second switch circuit 127 includes an N-type MOS transistor 127a and a P-type MOS transistor 127b.

Of these, the source electrode of the N-type MOS transistor 127a is connected to the second power supply line 112, the drain electrode is connected to the pixel electrode 121 via the common output terminal P2, and the gate electrode is the drain electrode of the driving TFT 124 and the first It is connected to the common input terminal P1 of the switch circuit 126 and the second switch circuit 127.

Further, the source electrode of the P-type MOS transistor 127b is connected to the second power supply line 112, the drain electrode is connected to the pixel electrode 121 via the common output terminal P2, and the gate electrode is connected to the common input terminal P1'. ..

Next, a driving method of the electrophoresis display device including the active matrix circuit board 100 shown in FIG. 10 will be described. Since the driving method is the same as the driving method described with reference to FIGS. 4 and 5, it is basic. The description of the driving method will be omitted.

On the other hand, in the present embodiment, if necessary, a drive method in which the drive signal supplied from the first power supply line 111 and the drive signal supplied from the second power supply line 112 are periodically replaced may be adopted. That is, the drive signal supplied to the first power supply line 111 is temporarily changed from V to 0 [V], and the drive signal supplied to the second power supply line 112 is changed from 0 [V] to V. After passing through the "opposite state of the drive signal", the "alternate state of the drive signal" may be periodically performed to return to the original "normal state of the drive signal".

Even if the drive signals are alternated in this way, the first switch circuit 126 and the second switch circuit 127 according to the present embodiment operate complementarily to each other, so that the same on / off control as described above is possible.

In addition, according to such alternation of drive signals, a defect due to the bias of the image data corresponding to the pixel 102, that is, the display content is biased to either black display or white display, for example, and the first switch circuit It is possible to prevent the occurrence of a problem caused by the continuous application of the voltage to only one of the 126 and the second switch circuit 127.

If the voltage is continuously applied to only one of the switch circuits, there is a concern that the characteristics of the semiconductor material contained in the switch circuit may be deteriorated.

On the other hand, by periodically alternating the drive signals, it is possible to prevent the voltage from being continuously applied to only one of the switch circuits even if the displayed contents are biased. As a result, deterioration of the characteristics of the semiconductor material can be suppressed, and the occurrence of such adverse effects can be prevented.

However, when the drive signals are alternated, in the "opposite state of the drive signal", the direction of the electric field applied to the electrophoretic material layer 7 is opposite, so that the displayed contents are also inverted. In order to avoid such inversion of the display content, the image signal supplied to the data line 105 may also be inverted in synchronization with the alternation of the drive signal. That is, when it is in the "opposite state of the drive signal", the image signal corresponding to the display content (display content in which the gradation is inverted) in which black and white are exchanged in the original display content is transmitted to the data line 105 accordingly. It should be supplied. As a result, even if the directions of the electric fields are opposite, the displayed contents are the originally intended ones, so that it is possible to avoid the influence on the displayed contents due to the alternation of the drive signals.

Such alternation of drive signals can be performed, for example, by a circuit (not shown) included in the power supply modulation unit 108. For example, a switch circuit in which the connection destination of the third switch circuit 1082 is exchanged between the first voltage end 1092 and the second voltage end 1093, and the connection destination of the fourth switch circuit 1083 are the second voltage end 1093 and the first voltage end. A switch circuit to be replaced with the 1092 may be provided in the power supply modulation unit 108.

Further, the inversion of the image signal can also be performed by the control unit 110 or a device higher than the control unit 110.

The degree of deterioration of the characteristics of the semiconductor material as described above depends on the time when the voltage is applied (voltage application time). Therefore, in principle, the drive signals may be alternated so that the voltage application time in each switch circuit is split in half.

By the way, the above-mentioned problems are likely to become apparent in the pixels 102 whose display is frequently rewritten. In such a pixel 102, since it is necessary to run the particles 71 frequently, the voltage application time in the first switch circuit 126 and the second switch circuit 127 becomes long after all. As a result, there is a problem that the reliability of the active matrix circuit board 100 tends to decrease.

For example, when the clock is displayed on the electrophoresis display device 1 which displays black and white, especially when the seconds are displayed, the display is frequently rewritten. Specifically, regardless of whether it is a digital clock display or an analog clock display, the black display and the white display are frequently rewritten in some of the pixels that display the clock. However, since the display rewriting pattern differs depending on the arrangement of the pixels 102, it is necessary to optimize the frequency in order to perform "alternation of drive signals" at a common frequency for a plurality of pixels 102. ..

Therefore, in such a pixel 102, it is preferable that the alternation frequency of the drive signal is either every 10 times of rewriting the display of the pixel 102 or every 60 times of rewriting the display.

For example, in the case of a digital clock display, in the pixel 102 that displays the first-order seconds, the rewriting pattern between the black display and the white display goes around in 10 times (10 seconds). Therefore, the drive signal is alternated in a cycle corresponding to the 10 rewrites, for example, a cycle in which the positive state and the negative state of the drive signal are exchanged every 10 rewrites. As a result, the voltage application time can be evenly allocated between the first switch circuit 126 and the second switch circuit 127.

Further, for example, in the case of an analog clock display, in the pixel 102 that performs the second display, the rewriting pattern between the black display and the white display goes around 60 times (60 seconds). Therefore, by alternating the drive signal with a cycle corresponding to the 60 times of rewriting, for example, a cycle in which the positive state and the negative state of the drive signal are exchanged every 60 times of rewriting, the first switch circuit 126 and the first switch circuit 126 are changed. The voltage application time can be evenly allocated to and from the two-switch circuit 127.

By adopting the driving method as described above, the reliability of the active matrix circuit board 100 can be further improved without affecting the displayed contents.
In addition, even in such a third embodiment, the same effect as that of the first embodiment can be obtained.

<< Fourth Embodiment >>
Next, a fourth embodiment of the present invention will be described.

FIG. 11 is a diagram showing a circuit configuration in one pixel and a common electrode of the active matrix circuit board included in the fourth embodiment of the display device of the present invention.

Hereinafter, the fourth embodiment will be described, but in the following description, the differences from the second and third embodiments will be mainly described, and the description of the same matters will be omitted. The same reference numerals are given to the same configurations as those of the second and third embodiments described above.
The active matrix circuit board 100 according to the present embodiment is the same as that of the third embodiment except that the first capacitor 131 and the second capacitor 132 are provided.

As described above in the second embodiment, the first capacitor 131 is provided between the first power supply line 111 and the third power supply line 113.

By providing such a first capacitor 131, the first capacitor 131 can be charged while a potential difference is formed between the first power supply line 111 and the third power supply line 113. Therefore, even when the electric capacity of the electrophoretic substance layer 7 is not large, sufficient electric energy can be stored in the first capacitor 131 instead. As a result, the particles 71 can be more reliably migrated even during a period in which the voltage is not directly applied from the power supply unit 109, and the migration speed can be increased as compared with the first embodiment.

Further, the second capacitor 132 is also provided between the second power supply line 112 and the third power supply line 113 as described above in the second embodiment.

By providing such a second capacitor 132, the second capacitor 132 can be charged while a potential difference is formed between the second power supply line 112 and the third power supply line 113. Therefore, even when the electric capacity of the electrophoretic substance layer 7 is not large, sufficient electric energy can be stored in the second capacitor 132 instead. As a result, the particles 71 can be more reliably migrated even during a period in which the voltage is not directly applied from the power supply unit 109, and the migration speed can be increased as compared with the first embodiment.

Further, in the third embodiment, the electric energy stored in the electrophoresis material layer 7 changes according to the display content of the electrophoresis display device 1. On the other hand, in the present embodiment, a constant electric energy can always be stored in the first capacitor 131 and the second capacitor 132. Therefore, it is also useful from the viewpoint of the stability of the effect.
In such a fourth embodiment, the same effect as that of the second embodiment can be obtained.

<Electronic equipment>
Next, an embodiment of the electronic device of the present invention will be described. The electronic device according to the present embodiment includes a display device according to the above embodiment.

FIG. 12 is a front view of a wristwatch to which an embodiment of the electronic device of the present invention is applied.
The wristwatch 401 (embodiment of the electronic device of the present invention) shown in FIG. 12 includes a watch case 402 and a pair of bands 403 connected to the watch case 402. An electrophoresis display device 405 (the embodiment of the display device of the present invention), a second hand 421, a minute hand 422, and an hour hand 423 are provided on the front surface of the watch case 402. A crown 410 as an operator and an operation button 411 are provided on the side surface of the watch case 402.

FIG. 13 is a side sectional view of the wristwatch shown in FIG.
A housing portion 402A is provided inside the watch case 402 shown in FIG. The movement 404 and the electrophoresis display device 405 are housed in the housing portion 402A. A transparent cover 407 made of glass or resin is provided on one end side (front side of the watch) of the accommodating portion 402A. A back cover 409 is screwed onto the other end side (back side of the watch) of the accommodating portion 402A via a packing 408, and the watch case 402 is sealed by the back cover 409 and the transparent cover 407.

The movement 404 has a hand movement mechanism (not shown) to which an analog pointer including a second hand 421, a minute hand 422, and an hour hand 423 is connected. This hand movement mechanism rotates and drives the analog pointer and functions as a time display unit that displays a set time.

The electrophoresis display device 405 is arranged on the front side of the watch of the movement 404 and constitutes the display unit of the wristwatch 401. The display surface of the electrophoresis display device 405 has a circular shape here, but may have other shapes such as a regular octagonal shape and a hexagonal shape. A through hole 405A that penetrates the front and back surfaces of the electrophoresis display device 405 is formed in the central portion of the electrophoresis display device 405. The shafts of the second wheel 424, the second wheel 425, and the cylinder wheel 426 of the hand movement mechanism (not shown) of the movement 404 are inserted into the through hole 405A. A second hand 421, a minute hand 422, and an hour hand 423 are attached to the tip of each shaft.

The electrophoresis display device 405 shown in FIGS. 12 and 13 is configured to display, for example, an image of a dial, but is configured to display a second hand, a minute hand, and an hour hand in addition to the dial. May be good. In that case, the second hand 421, the minute hand 422, the hour hand 423, the movement 404, and the like described above can be omitted. Further, instead of the so-called analog display that displays the second hand, the minute hand, and the hour hand, the digital display of the clock may be performed.

The electronic device of the present invention is applied to other than watches.
FIG. 14 is a perspective view showing the configuration of an electronic paper to which an embodiment of the electronic device of the present invention is applied.

The electronic paper 500 shown in FIG. 14 includes a display unit 501 (the embodiment of the display device of the present invention). The electronic paper 500 is flexible and includes a body 502 made of a rewritable sheet having the same texture and flexibility as conventional paper.

FIG. 15 is a perspective view showing the configuration of an electronic notebook to which an embodiment of the electronic device of the present invention is applied.

The electronic notebook 600 shown in FIG. 15 is formed by bundling a plurality of electronic papers 500 shown in FIG. 14 and sandwiching them between covers 601. The cover 601 includes display data input means (not shown) for inputting display data sent from, for example, an external device. As a result, the display contents can be changed or updated while the electronic papers are bundled according to the display data.

Since the electronic devices such as the wristwatch 401, the electronic paper 500, and the electronic notebook 600 as described above are provided with the display device of the present invention, they can enjoy the effects brought about by the active matrix circuit board 100, and thus display. The switching speed of is fast.

The display device, the driving method of the display device, and the electronic device of the present invention have been described above based on the illustrated embodiments, but the present invention is not limited thereto.

For example, in a display device and an electronic device, the configuration of each part can be replaced with an arbitrary configuration having the same function, or any other configuration can be added. Specifically, memory circuits, switch circuits, capacitors, diodes and the like can be replaced by circuits and elements having similar functions.

Further, the driving method of the display device may be a method in which a process of an arbitrary purpose is added to the above-described embodiment.

Further, the display device is not limited to the electrophoresis display device, and may be another display device (for example, a liquid crystal display device or the like) that drives a display medium by using an electric field to switch the display.

1 ... Electromagnetic display device, 7 ... Electrolytic material layer, 10 ... Back plane, 20 ... Front plane, 70 ... Dispersion liquid, 71 ... Particles, 71a ... Black particles, 71b ... White particles, 72 ... Dispersion medium, 91 ... Partition, 92 ... Sealing part, 100 ... Active matrix circuit board, 102 ... Pixel, 103 ... Image display part, 104 ... Scan line, 105 ... Data line, 106 ... Scan line drive circuit, 107 ... Data line drive circuit, 108 ... power supply modulation unit, 109 ... power supply unit, 110 ... control unit, 111 ... first power supply line, 112 ... second power supply line, 113 ... third power supply line, 114 ... fourth power supply line, 115 ... fifth power supply line, 119 ... power supply circuit, 120 ... electrode substrate, 121 ... pixel electrode, 124 ... driving TFT, 125 ... memory circuit, 126 ... first switch circuit, 126a ... P-type MOS transistor, 126b ... N-type MOS transistor, 127 ... 2-switch circuit, 127a ... N-type MOS transistor, 127b ... P-type MOS transistor, 131 ... 1st condenser, 132 ... 2nd condenser, 201 ... opposite board, 202 ... common electrode, 401 ... watch, 402 ... watch case, 402A ... Housing, 403 ... Band, 404 ... Movement, 405 ... Electromagnetic display, 405A ... Through hole, 407 ... Transparent cover, 408 ... Packing, 409 ... Back cover, 410 ... Crown, 411 ... Operation button, 421 ... Second hand 422 ... Minute hand, 423 ... Hour hand, 424 ... Second wheel, 425 ... Second wheel, 426 ... Transistor, 500 ... Electronic paper, 501 ... Display, 502 ... Main body, 600 ... Electronic note, 601 ... Cover, 1081 ... Common electrode switch circuit, 1081a ... contact, 1081b ... contact, 1082 ... third switch circuit, 1083 ... fourth switch circuit, 1091 ... power supply, 1092 ... first voltage end, 1093 ... second voltage end, 1094 ... power supply, 1251 ... Condenser, 1252 ... P-type MOS transistor, 1253 ... P-type MOS transistor, 1254 ... N-type MOS transistor, 1255 ... N-type MOS transistor, 1261 ... P-type MOS transistor, 1271 ... N-type MOS transistor, P1 ... Common input terminal , P1'... common input terminal, P2 ... common output terminal

Claims (10)

A substrate having an image display unit including pixels,
1st power line, 2nd power line and 3rd power line,
Pixel electrodes provided corresponding to the pixels and
A memory circuit provided corresponding to the pixel and capable of holding and outputting either the first state or the second state, and
The common electrode connected to the third power supply line and
A power supply unit including a first voltage end that outputs a first potential and a second voltage end that outputs a second potential different from the first potential.
A common electrode switch circuit that alternately conducts between the third power supply line and either the first voltage end or the second voltage end.
A second power line provided between the first power supply line and the pixel electrode, which conducts when the output from the memory circuit is in the first state and shuts off when the output from the memory circuit is in the second state. 1 switch circuit and
A second power line provided between the second power supply line and the pixel electrode, which conducts when the output from the memory circuit is in the second state and shuts off when the output from the memory circuit is in the first state. 2 switch circuit and
When the third power supply line is conducting with the second voltage end, it conducts between the first power supply line and the first voltage end, and the third power supply line conducts with the first voltage end. When there is, a third switch circuit that cuts off between the first power supply line and the first voltage end, and
A display device having a first capacitor provided between the first power supply line and the third power supply line. Further, when the third power supply line is conducting with the first voltage end, it conducts between the second power supply line and the second voltage end, and the third power supply line conducts with the second voltage end. The display device according to claim 1, further comprising a fourth switch circuit that cuts off between the second power supply line and the second voltage end. A substrate having an image display unit including pixels,
1st power line, 2nd power line and 3rd power line,
Pixel electrodes provided corresponding to the pixels and
A memory circuit provided corresponding to the pixel and capable of holding and outputting either the first state or the second state, and
The common electrode connected to the third power supply line and
A power supply unit including a first voltage end that outputs a first potential and a second voltage end that outputs a second potential different from the first potential.
A common electrode switch circuit that alternately conducts between the third power supply line and either the first voltage end or the second voltage end.
A second power line provided between the first power supply line and the pixel electrode, which conducts when the output from the memory circuit is in the first state and shuts off when the output from the memory circuit is in the second state. 1 switch circuit and
A second power line provided between the second power supply line and the pixel electrode, which conducts when the output from the memory circuit is in the second state and shuts off when the output from the memory circuit is in the first state. 2 switch circuit and
When the third power supply line is conducting with the second voltage end, it conducts between the first power supply line and the first voltage end, and the third power supply line conducts with the first voltage end. When there is, a third switch circuit that cuts off between the first power supply line and the first voltage end, and
A display device having a second capacitor provided between the second power supply line and the third power supply line. Further, when the third power supply line is conducting with the first voltage end, it conducts between the second power supply line and the second voltage end, and the third power supply line conducts with the second voltage end. The display device according to claim 3, further comprising a fourth switch circuit that cuts off between the second power supply line and the second voltage end. further,
Scanning line and
Data line and
A pixel switching element provided corresponding to the pixel and provided between the scanning line and the data line and the memory circuit,
The display device according to claim 1 or 2. The display device according to any one of claims 1 to 4, further comprising an electro-optical material layer provided between the pixel electrode and the common electrode. A substrate having an image display unit including pixels,
1st power line, 2nd power line and 3rd power line,
A power source that outputs a first potential, a second potential different from the first potential, and a third potential and a fourth potential having the same high-low relationship as the high-low relationship between the first potential and the second potential. Department and
Power supply modulation in which the first potential is supplied to the first power supply line, the second potential is supplied to the second power supply line, and the third potential and the fourth potential are alternately supplied to the third power supply line. Department and
Pixel electrodes provided corresponding to the pixels and
A memory circuit provided corresponding to the pixel and capable of holding and outputting either the first state or the second state, and
The common electrode connected to the third power supply line and
A second power line provided between the first power supply line and the pixel electrode, which conducts when the output from the memory circuit is in the first state and shuts off when the output from the memory circuit is in the second state. 1 switch circuit and
A second power line provided between the second power supply line and the pixel electrode, which conducts when the output from the memory circuit is in the second state and shuts off when the output from the memory circuit is in the first state. 2 switch circuit and
Have,
When the fourth potential is supplied to the third power supply line, the power supply modulation unit conducts between the first power supply line and the power supply unit, and the third potential is supplied to the third power supply line. A display device including a third switch circuit that cuts off between the first power supply line and the power supply unit when the display device is used. The power supply modulation unit further conducts between the second power supply line and the power supply unit when the third potential is supplied to the third power supply line, and the fourth potential is connected to the third power supply line. The display device according to claim 7, further comprising a fourth switch circuit that cuts off between the second power supply line and the power supply unit when is supplied. A substrate having an image display unit including pixels,
1st power line, 2nd power line and 3rd power line,
A power supply unit that applies a potential difference between the first power supply line and the third power supply line and between the second power supply line and the third power supply line, respectively.
Pixel electrodes provided corresponding to the pixels and
A memory circuit provided corresponding to the pixel and capable of holding and outputting either the first state or the second state, and
The common electrode connected to the third power supply line and
A second power line provided between the first power supply line and the pixel electrode, which conducts when the output from the memory circuit is in the first state and shuts off when the output from the memory circuit is in the second state. 1 switch circuit and
A second power line provided between the second power supply line and the pixel electrode, which conducts when the output from the memory circuit is in the second state and shuts off when the output from the memory circuit is in the first state. 2 switch circuit and
Is a method of driving a display device having
The first step of applying a potential difference between the first power supply line and the third power supply line and between the second power supply line and the third power supply line, and
In the first step, the second step of electrically floating the power supply line having a potential difference between the first power supply line and the third power supply line among the second power supply lines,
Have a,
In the first step, either the first power supply line and the third power supply line or the second power supply line and the third power supply line are charged.
In the second step, an electric field is generated between the pixel electrode and the common electrode by discharging the electric charge charged in the first step.
A method of driving a display device, which is characterized in that. An electronic device comprising the display device according to any one of claims 1 to 8.

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