JP2009229911A - Electrophoretic display device and driving device of electrophoretic display device - Google Patents

Abstract

An electrophoretic display device capable of reducing the occurrence of malfunction due to an impact is provided.
An element substrate having a display area, an electrophoretic sheet having a common electrode, an electrophoresis layer and an adhesive layer provided on a transparent substrate, and bonded to the display area of the element substrate via the adhesive layer; A conductive portion which is provided on the element substrate and electrically conducts between the element substrate and the common electrode, and is provided in a region on one side of the display region in plan view on the element substrate. And a control circuit connected to the conducting portion and capable of controlling the potential of the common electrode via the conducting portion, and at least a part of the conducting portion is provided in the region on the one side in a plan view. ing.
[Selection] Figure 2

Description

  The present invention relates to an electrophoretic display device and a driving method of the electrophoretic display device, and more particularly to a display erasing method in the display device.

  In recent years, electrophoretic display devices have been used as display units for electronic paper and the like. The electrophoretic display device has an electrophoretic dispersion liquid in which a plurality of electrophoretic particles are dispersed in a liquid phase dispersion medium, and the electrophoretic dispersion is changed by changing the distribution state of the electrophoretic particles by applying an electric field. This is a device that utilizes the change in the optical characteristics of the liquid for display. As a specific configuration of the electrophoretic display device, a configuration in which an electrophoretic sheet is attached to a display area of an element substrate and a protective substrate is attached to the electrophoretic sheet is known. Hereinafter, a configuration including the element substrate and the electrophoretic sheet is also referred to as a “display panel”.

  The element substrate has a configuration in which a plurality of pixel electrodes and elements are formed in a display area on a substrate made of, for example, glass. The electrophoresis sheet has a configuration in which an electrophoresis layer and an adhesive layer are formed on a transparent sheet on which a common electrode made of ITO or the like is deposited. The transparent sheet is often composed of, for example, polyethylene terephthalate (PET). Examples of the electro-optic layer include a configuration in which microcapsules in which electrophoretic particles and a liquid layer dispersion medium for dispersing the electrophoretic particles are enclosed are spread over the entire surface of the sheet. The element substrate and the common electrode are generally connected by a vertical conduction material disposed on the element substrate, and a voltage signal is supplied to the vertical conduction material from an external circuit, for example. Many.

Since the electrophoretic display device has a function of maintaining a display state even when an electric field is not applied to the electrophoretic layer, the display panel is in a state where the display is performed, for example, due to an impact such as dropping. If it breaks down, the display will remain. Therefore, for example, there may be a case where confidential documents remain displayed, which is not necessarily preferable from the viewpoint of security. For this, for example, as shown in Patent Document 1, there has been known a technique capable of erasing the display when a drive circuit or a power supply circuit fails.
JP 2005-257755 A

  However, the configuration of Patent Document 1 is effective only when a failure occurs in a circuit such as a drive circuit or a power supply circuit. For example, the element substrate is damaged by an impact, and the connection between the external circuit and the vertical conductive member is not achieved. Once cut, the voltage signal could not be applied to the common electrode and the display could not be erased. In particular, in the conventional configuration, there are many configurations in which the external circuit and the vertical conductive material are arranged with the display area interposed therebetween, and thus the connection between the external circuit and the vertical conductive material is likely to be broken due to damage to the element substrate. There was a problem.

  In view of the circumstances as described above, an object of the present invention is to provide an electrophoretic display device capable of erasing an image even when a display panel fails. Another object is to provide a driving method of an electrophoretic display device that can erase an image even when a display panel is out of order.

  In order to achieve the above object, an electrophoretic display device according to the present invention includes an element substrate having a display area, a common electrode and an electrophoretic layer provided in this order on a transparent substrate, and the display of the element substrate. An electrophoretic sheet bonded to a region, a conductive portion provided on the element substrate and electrically conducting between the element substrate and the common electrode, and the display region in a plan view on the element substrate. A control circuit provided in an outer region and connected to the conduction part and capable of controlling the potential of the common electrode via the conduction part, and the control circuit and a part of the conduction part include It is characterized by being adjacent.

  According to the present invention, at least a part of the conducting portion that conducts electricity between the element substrate and the common electrode, and the potential of the common electrode can be controlled via the conducting portion while being connected to the conducting portion. Since the control circuit is adjacent to the display region in plan view on the element substrate, the connection length between the conductive portion and the control circuit can be shortened compared to the conventional configuration. By shortening the connection length between the conduction part and the control circuit, the connection between the conduction part and the control circuit is more likely to be disconnected even when the display panel is damaged due to an impact, for example. Can prevent. Thereby, generation | occurrence | production of the malfunctioning by an impact can be decreased more. Further, even when the display panel fails, it is possible to apply a potential to the common electrode from the control circuit, and it is possible to erase the image displayed on the display panel.

In the electrophoretic display device, a connection substrate is connected to a region adjacent to a part of the conductive portion on the element substrate, and the control circuit is provided on the connection substrate. And
According to the present invention, the connection substrate is connected to a region adjacent to a part of the conductive portion on the element substrate, and the control circuit is provided on the connection substrate. Can be prevented.

In the electrophoretic display device, the element substrate is provided in a rectangular shape in plan view, the control circuit is connected along one side of the element substrate, and the conductive portion is along the one side. It is provided in a different position.
According to the present invention, the element substrate is provided in a rectangular shape in plan view, the control circuit is connected along one side of the element substrate, and the conductive portion is provided at a position along the one side. Therefore, even when the element substrate is damaged due to an impact, it is possible to prevent the connection between the conduction portion and the control circuit from being disconnected with a higher possibility.

The electrophoretic display device is characterized in that the conductive portion is provided at a corner of the element substrate in a plan view.
According to the present invention, since the conducting portion is provided at the corner portion of the element substrate in plan view, it is possible to prevent the connection between the conducting portion and the control circuit from being disconnected with a higher possibility. be able to.

The electrophoretic display device is characterized in that a plurality of the conductive portions are provided.
According to the present invention, since a plurality of conducting portions are provided, for example, even when the connection between the control circuit and one of the conducting portions is disconnected, the connection between the control circuit and the common electrode is performed. Will not be completely disconnected. Thereby, it is possible to prevent the connection between the conduction part and the control circuit from being disconnected with a higher possibility.

The electrophoretic display device is characterized in that at least two of the plurality of conducting portions are electrically connected.
According to the present invention, since at least two of the plurality of conductive portions are electrically connected, it is possible to prevent the voltage from being shifted between the plurality of electrically connected conductive portions. Can do.

In the electrophoretic display device, the control circuit outputs a voltage for erasing display on the display area to the conduction portion based on a predetermined signal.
According to the present invention, since the control circuit outputs the voltage for erasing the display in the display area to the conduction portion based on the predetermined signal, the voltage signal can be output to the common electrode with higher possibility. it can.

The electrophoretic display device further includes an input switch for inputting the predetermined signal to the control circuit.
According to the present invention, since the input switch for inputting a signal to the control circuit is further provided, the display can be erased according to the judgment of the user who operates the input switch. Thereby, the operability of the electrophoretic display device can be improved.

The electrophoretic display device further includes a detection unit that detects an impact on the control circuit, and the predetermined signal is a signal based on a detection result of the detection unit.
According to the present invention, since the detection unit for detecting the impact on the control circuit is further provided and the predetermined signal is a signal based on the detection result by the detection unit, when a certain impact is applied to the control circuit, The display can be automatically deleted. It is also possible to combine the signal based on the detection result and the signal based on the input by the user.

  An electrophoretic display device driving method according to the present invention is an electrophoretic display device driving method including an electrophoretic layer between a transparent substrate having a common electrode formed on one surface and an element substrate having a pixel electrode. Generating a potential difference between the common electrode and the pixel electrode to display an image in a display region including the region where the pixel electrode is formed in a plan view; and Applying a rectangular wave that periodically repeats one potential and a second potential higher than the first potential to erase the image displayed in the display area.

  According to the present invention, by generating a potential difference between the common electrode and the pixel electrode, an image is displayed on the display region including the region where the pixel electrode is formed in plan view, and the first potential and the first potential are displayed on the common electrode. Since the image displayed in the display area is erased by applying a rectangular wave that periodically repeats a second potential higher than one potential, even if the display panel breaks down, The displayed image can be erased.

The driving method of the electrophoretic display device is characterized in that, in the step of erasing the image, the pixel electrode has a high impedance.
According to the present invention, since the pixel electrode has high impedance in the image erasing step, as the potential of the common electrode periodically repeats between the first potential and the second potential, the common electrode The potential of the pixel electrode changes so as to be delayed from the change of the potential. This potential change can cause a potential difference between the pixel electrode and the common electrode.

Embodiments of the present invention will be described below with reference to the drawings.
FIG. 1 is a perspective view showing a configuration of an electrophoretic display device 100 according to the present embodiment.

  As shown in the figure, the electrophoretic display device 100 includes a display unit 101, a housing 102, and input switches 103 and 104, and the display unit 101 is held by the housing 102. As the display unit 101, for example, the electrophoretic display panel 1 is mounted. The input switch 103 is a power switch of the electrophoretic display device 100, for example, and the input switch 104 is a switch for erasing the display of the display unit 101, for example.

FIG. 2 is a plan view showing a schematic configuration of the electrophoretic display panel 1 according to the present embodiment. FIG. 3 is a diagram showing a configuration along the section AA in FIG.
2 and 3, the electrophoretic display panel 1 includes an element substrate 2, an electrophoretic sheet 3, and a connection substrate F. The electrophoretic sheet 3 is attached to the surface of the element substrate 2 and the electrophoretic sheet 3 is attached. The connection substrate F is connected to the surface of the element substrate 2.

  The electrophoretic display panel 1 is provided with a display area 5 for displaying images such as still images and moving images. A plurality of pixels arranged in a matrix are provided in the display area 5, and display is performed for each pixel. A region 6 around the display region 5 is a non-display region 6 where no image is displayed. The non-display area 6 is not provided with pixels, and is provided with drive circuit elements 22 and 23, a terminal 24, and the like.

  The element substrate 2 includes a substrate 20 having a thickness of about 0.5 mm, for example, and a drive layer 21 including pixel electrodes and elements formed on the substrate. Examples of the substrate 20 include inorganic substrates such as a glass substrate, a quartz substrate, a silicon substrate, and a gallium arsenide substrate, polyimide, polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polymethyl methacrylate (PMMA), and polycarbonate (PC). A plastic substrate (resin substrate) composed of polyethersulfone (PES), aromatic polyester (liquid crystal polymer), or the like can be used.

  The drive layer 21 is formed in a region corresponding to the display region 5 in the substrate 20. In the drive layer 21, a pixel electrode 25 and a switching element 26 provided in each pixel, a data line (not shown) and a scanning line connected to the switching element 26 are formed. Each pixel electrode 25 is connected to a storage capacitor (not shown).

  A planar formation region of the drive layer 21 substantially coincides with the display region 5, and the drive circuit elements 22 and 23 are provided in the peripheral portion (non-display region 6) of the drive layer 21. The drive circuit elements 22 and 23 are electrically connected to data lines and scanning lines, and supply signals to the drive layer 21. A plurality of terminals 24 are provided along one side (right end in the drawing) of the four sides of the element substrate 2, and a part of these terminals 24 is driven by a wiring (not shown) formed on the element substrate 2. Connected to elements 22 and 23. These terminals 24 are connected to the connection board F. A control circuit 40 is provided on the connection board F.

  On the element substrate 2, vertical conduction members (conduction portions) 9 are respectively arranged at two corners of the side where the connection substrate F is provided in plan view. The vertical conduction member 9 is connected to the control circuit 40 of the connection board F through the wiring 9a and a part of the terminal 24 described above. Therefore, the connection length on the element substrate 2 between the vertical conduction member 9 and the control circuit 40 is the length of the wiring 9 a between the terminal 24 and the vertical conduction member 9.

  By making the connection length between the vertical conduction member 9 and the control circuit 40 as described above, even when the element substrate 2 is damaged due to an impact, for example, the connection between the vertical conduction member 9 and the control circuit 40 is performed. The disconnection of the connection (wiring 9a) can be prevented with a higher possibility.

  Here, an example is shown in which two upper and lower conductive members 9 are arranged, but the present invention is not limited to this. For example, one or three or more vertical conductive members 9 are provided. It doesn't matter.

The electrophoretic sheet 3 has a transparent substrate 30, a common electrode 35, an electrophoretic layer 31, and an adhesive layer 33.
The transparent substrate 30 has a thickness of, for example, about 0.2 mm, and holds the electrophoretic layer 31. For example, the transparent substrate 30 has high light transmittance such as polyethylene terephthalate (PET), polyethersulfone (PES), and polycarbonate (PC). A rectangular substrate made of a material. The surface 30 a side of the transparent substrate 30 is the display surface side of the electrophoretic display panel 1.

  The common electrode 35 is formed almost on the entire inner surface 30 b of the transparent substrate 30. The common electrode 35 is made of a conductive material having high light transmission, such as ITO, and is connected to the element substrate 2 by the above vertical conductive material 9.

The electrophoretic layer 31 has a plurality of microcapsules 32.
The microcapsule 32 is a substantially spherical capsule in which an electrophoretic dispersion is enclosed, and the diameter of each capsule is substantially the same (50 μm to 100 μm). Examples of the material for forming the capsule wall film of the microcapsule 32 include compounds such as a gum arabic / gelatin composite film, urethane resin, urea resin, and urea resin. The electrophoretic dispersion liquid enclosed in the microcapsule 32 includes a plurality of electrophoretic particles and a liquid layer dispersion medium for dispersing the electrophoretic particles.

  Examples of the liquid layer dispersion medium include water, alcohol solvents, various esters, ketones, aliphatic hydrocarbons, alicyclic hydrocarbons, aromatic hydrocarbons, halogenated hydrocarbons, carboxylates, and other various oils. These can be used alone, or a mixture of these with a surfactant or the like.

  As the electrophoretic particles, organic or inorganic particles (polymer or colloid) having a property of moving by electrophoresis due to a potential difference in a liquid phase dispersion medium can be used. Specifically, black pigments such as carbon black and aniline black, white pigments such as titanium dioxide, monoazo azo pigments, yellow pigments such as isoindolinone, monoazo azo pigments, red pigments such as quinacridone red, phthalocyanine One or more of blue pigments such as blue and green pigments such as phthalocyanine green can be used. These pigments include electrolytes, surfactants, metal soaps, resins, rubbers, oils, varnishes, charge control agents composed of particles such as compounds, titanium-based coupling agents, aluminum-based coupling agents, silanes as necessary. A dispersant such as a system coupling agent, a lubricant, a stabilizer, and the like can be added.

  In the microcapsule 32, for example, two types of electrophoretic particles of titanium dioxide which is a white pigment and carbon black which is a black pigment are encapsulated, one of which is negatively charged and the other of which is positively charged. Of course, other electrophoretic particles may be used, or only one type of electrophoretic particle may be used, and the electrophoretic particles may be moved to the common electrode side or the pixel electrode side so that display can be performed.

  The adhesive layer 33 is a thermosetting adhesive that also serves as a binder. The adhesive layer 33 is preferably an adhesive having good affinity for the capsule wall film of the microcapsule 32, excellent adhesion to the common electrode and the pixel electrode, and good insulation. Moreover, although it is a thermosetting type, the adhesive agent which has elasticity after hardening is preferable.

Next, the operation of the electrophoretic display panel 1 configured as described above will be briefly described.
When a voltage is applied between the pixel electrode 25 and the common electrode 35 so that the voltage of the common electrode 35 becomes relatively high, the positively charged black electrophoretic particles are out of the pixels in the microcapsule 32 by the Coulomb force. It is drawn toward the electrode 25 side. On the other hand, negatively charged white electrophoretic particles are attracted toward the common electrode 35 in the microcapsule 32 by Coulomb force. As a result, white electrophoretic particles gather on the transparent substrate 30 side in the microcapsule 32, and the color (white) of the white electrophoretic particles is displayed in the display area 5 of the electrophoretic display panel 1. The Rukoto.

  On the contrary, when a voltage is applied between the pixel electrode 25 and the common electrode 35 so that the potential of the pixel electrode 25 becomes relatively high, the negatively charged white electrophoretic particles are moved to the pixel electrode 25 side by Coulomb force. Be drawn to. On the other hand, the positively charged black electrophoretic particles are attracted toward the common electrode 35 by the Coulomb force. As a result, black electrophoretic particles gather on the transparent substrate 30 side in the microcapsule 32, and the color (black) of the black electrophoretic particles is displayed in the display area 5 of the electrophoretic display panel 1. It will be.

FIG. 4 is a block diagram showing the configuration of the connection board F. As shown in FIG.
As shown in the figure, on the connection substrate F, as the control circuit 40, an input unit 41, a CPU 42, a memory 43, a drive circuit 44, a VRAM 45, a common electrode power circuit 46, and a pixel electrode power circuit. 47 is provided.

  The input unit 41 is connected to the input switch 104, and an input signal including a signal from the input switch 104 is supplied. This input signal is transmitted to the CPU 42, and a control signal is generated by the CPU 42. For example, when the signal from the input switch 104 is input via the input unit 41, the CPU 42 generates a signal for erasing the display by the display area 5 and outputs a signal for setting the pixel electrode 25 to high impedance. It is designed to generate.

  A signal generated by the CPU 42 is supplied to the drive circuit 44. A signal from the drive circuit 44 is directly supplied to the element substrate 2 and is also supplied to the element substrate 2 through the common electrode power supply circuit 46 and the pixel electrode power supply circuit 47. . A signal from the common power supply circuit 46 is supplied to the common electrode 35 through the terminal 24, the wiring 9 a, and the vertical conduction member 9.

FIG. 5 is a circuit diagram showing a configuration of the common electrode power supply circuit 46.
As shown in the figure, the common electrode power supply circuit 46 includes a battery 46a, a boost regulator 46b, and transistors 46c and 46d. The voltage from the battery 46a is supplied to the source side of the transistor 46c through the boost regulator 46b. The drain side of the transistor 46 c is connected to the drain side of the transistor 46 d and to the terminal 24 of the element substrate 2. The source side of the transistor 46d is in a grounded state. The gate sides of the transistors 46c and 46d are connected to the drive circuit 44, respectively. The pixel electrode power supply circuit 47 also has the same circuit configuration as that of the common electrode power supply circuit 46.

  When the electrophoretic display device 100 configured as described above is used, the electrophoretic display device 100 is dropped in a state where, for example, an image that is confidential information is displayed on the display unit 101, thereby configuring the display unit 101. When the element substrate 2 of the electrophoretic display panel 1 is damaged, the image is held on the display unit 101 while being displayed.

  At this time, when the user operates the input switch 104, a signal from the input switch 104 is supplied to the input unit 41, and the CPU 42 generates a signal for erasing the image display. This signal is supplied to the terminal 24 of the element substrate 2 through the common electrode power circuit 46. In the present embodiment, since the connection length between the vertical conduction member 9 and the control circuit 40 is shorter than that of the conventional configuration, the vertical conduction member 9 and the control circuit even when the element substrate 2 is damaged. The connection with 40 is difficult to be disconnected. For this reason, the possibility that a voltage for erasing the image display is applied to the common electrode 35 via the vertical conductive member 9 is extremely increased.

  In the CPU 42, a signal for making the pixel electrode 25 high impedance is generated by a signal from the input switch 104. This signal is also supplied to the terminal 24 of the element substrate 2 through the pixel electrode power supply circuit 47, and the pixel electrode 25 enters a high impedance state.

  FIG. 6 is a graph showing waveforms of voltages applied to the common electrode 35 and the pixel electrode 25. The vertical axis indicates the magnitude of the voltage as a high level (H) as the second potential and a low level (L) as the first potential. The horizontal axis indicates the voltage application time. The solid line in the graph indicates the waveform of the voltage applied to the common electrode 35, and the broken line in the graph indicates the waveform of the voltage applied to the common electrode 25.

  Here, a driving method for erasing an image displayed on the display panel in the electrophoretic display device 100 will be specifically described with reference to FIG.

  The pixel circuit for applying a potential to each pixel electrode 25 will be described as being of the 1T1C type. In the 1T1C type, an N-MOS transistor (T: pixel switching element) having a gate terminal connected to a scanning line and a source terminal connected to a data line, and a capacitor (C: holding) connected to the drain terminal of the transistor (Capacitance). Note that the drain terminal of the transistor is connected to the corresponding pixel electrode 25, and the other end of the capacitor is connected to the ground (potential).

  As shown in the figure, as the voltage signal applied to the common electrode 35 when erasing the image display, for example, a signal (rectangular wave) that switches between a high level and a low level at regular intervals (cycles) is preferable. When this signal is input to the common electrode 35, the potential of the pixel electrode 25 that is in a high impedance state is also affected by the potential of the common electrode 35.

  At this time, the electrophoretic layer 31 sandwiched between the pixel electrode 25 and the common electrode 35 serves as a resistance component, and as shown in FIG. 6, the change in the potential of the pixel electrode 25 corresponds to the change in the potential of the common electrode 35. It happens to be late. Due to this delay in potential change, a potential difference is temporarily generated between the pixel electrode 25 and the common electrode 35.

  A voltage is applied between the pixel electrode 25 and the common electrode 35 due to the generated potential difference, and the display is updated by the influence of the electric field due to the voltage. When a signal is supplied to the common electrode 35 while switching between a high level and a low level as in the present embodiment, a potential difference due to a delay in potential change occurs every time switching is performed. With this operation, the confidential information image displayed on the display unit 101 is erased.

  As described above, according to this driving method, an image can be erased even when the display panel is out of order. Therefore, for example, the electrophoretic display device 1 can be discarded without considering leakage of confidential information.

  This driving method can be applied not only to a 1T1C type pixel circuit but also to a pixel circuit that can apply a rectangular wave to the common electrode while making the pixel electrode high impedance. . For example, a pixel circuit having a latch circuit made of SRAM or the like between the drain terminal of the N-MOS transistor and the pixel electrode 25 without providing a capacitor may be used.

  As described above, according to the present embodiment, the vertical conduction member 9 that is electrically connected between the element substrate 2 and the common electrode 35 and the vertical conduction member 9 are connected to the vertical conduction member 9 and the vertical conduction member 9 is interposed therebetween. Since the control circuit 40 capable of controlling the potential of the common electrode 35 is provided on the element substrate 2 on the same side of the display region 5 in plan view, the vertical conductive member 9 and the control circuit 40 The connection length can be shortened compared to the conventional configuration. By shortening the connection length between the vertical conduction member 9 and the control circuit 40, the connection between the vertical conduction member 9 and the control circuit 40 is cut even when the element substrate 2 is damaged by an impact, for example. Can be prevented with a higher possibility. Thereby, the electrophoretic display device 100 that can reduce the occurrence of malfunction due to impact can be obtained.

The technical scope of the present invention is not limited to the above-described embodiment, and appropriate modifications can be made without departing from the spirit of the present invention.
For example, in the above-described embodiment, the vertical conductive member 9 is arranged one by one at the two corners on the right side of the drawing on the display substrate 2, but the present invention is not limited to this. FIG. 7 is a plan view showing the configuration of the electrophoretic display panel 1. As shown in the figure, the vertical conductive member 9 may be formed along the upper side in the drawing, the left side in the drawing, and the lower side in the drawing on the element substrate 2.

  In this case, a part of the vertical conduction member 9 is provided on the same side as the connection substrate F with respect to the display region 5. As described above, only a part of the vertical conductive member 9 may be provided on the same side as the connection substrate F with respect to the display region 5. Further, in the configuration shown in FIG. 7, the common electrode 35 can be connected to the vertical conduction member 9 in a wide area.

  In the above embodiment, the display image in the display area 5 is erased by operating the input switch 104 of the electrophoretic display device 100. However, the present invention is not limited to this. FIG. 8 is a plan view showing the configuration of the electrophoretic display panel 1. As shown in the figure, a configuration may be adopted in which a detection unit 48 that detects an impact of the control circuit 40 is arranged and a detection result by the detection unit 48 is input to the input unit 41.

  In this case, it is preferable that the CPU 42 generates a signal for erasing the display image in the display area 5 when the value of the impact detected by the detection unit 48 is equal to or greater than a preset threshold value. As a result, the display can be automatically erased when a certain impact is applied to the control circuit 40.

  Of course, the mode of erasing the display image based on the detection result of the detection unit 48 and the mode of erasing the display image by operating the input switch 104 may be combined. In this case, it is preferable that the user determine whether to delete the display image when the detection result of the detection unit 48 exceeds the threshold value.

  Moreover, in the said embodiment, although it was set as the structure by which the vertical conduction | electrical_connection materials 9 are not electrically connected on the element substrate 2, it is not restricted to this, For example, the vertical conduction | electrical_connection materials 9 are electrically connected. Of course, it does not matter as a structure to do. With this configuration, it is possible to prevent a potential difference from being generated between the upper and lower conductive members 9.

  In the above embodiment, when the display image is erased, the pixel electrode 25 is kept in a high impedance state, and high level and low level signals are alternately supplied to the common electrode 35. The present invention is not limited to this. For example, only a high level signal or only a low level signal may be supplied. Even in this case, it is possible to cause a delay in the change in potential difference on the pixel electrode 25 side.

1 is a perspective view showing a configuration of an electrophoretic display device according to a first embodiment of the present invention. FIG. 2 is a plan view showing a configuration of an electrophoretic display panel according to the present embodiment. FIG. 3 is a cross-sectional view illustrating a configuration of an electrophoretic display panel according to the present embodiment. The block diagram which shows the structure of a connection board | substrate. The circuit diagram which shows the structure of a common electrode power supply circuit. 4 is a timing chart showing voltage values applied to a common electrode and a pixel electrode. The top view which shows the other structure of the electrophoretic display apparatus which concerns on this invention. The top view which shows the other structure of the electrophoretic display apparatus which concerns on this invention.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Electrophoretic display panel 2 ... Element board | substrate 3 ... Electrophoresis sheet 5 ... Display area 6 ... Non-display area 9 ... Vertical conduction material 9a ... Wiring 24 ... Terminal 30 ... Transparent substrate 31 ... Electrophoretic layer 32 ... Microcapsule 33 ... Adhesive layer 40 ... Connection circuit F ... Connection substrate 100 ... Electrophoretic display device 104 ... Input switch

Claims (11)

An element substrate having a display area;
An electrophoretic sheet in which a common electrode and an electrophoretic layer are provided in this order on a transparent substrate, and are bonded to the display region of the element substrate;
A conductive portion provided on the element substrate and electrically conducting between the element substrate and the common electrode;
A control circuit which is provided in a region outside the display region in a plan view on the element substrate, is connected to the conductive portion, and is capable of controlling the potential of the common electrode via the conductive portion;
With
The electrophoretic display device, wherein the control circuit and a part of the conductive portion are adjacent to each other. A connection substrate is connected to a region adjacent to a part of the conducting portion on the element substrate,
The electrophoretic display device according to claim 1, wherein the control circuit is provided on the connection substrate. The element substrate is provided in a rectangular shape in plan view,
The control circuit is connected along one side of the element substrate,
The electrophoretic display device according to claim 1, wherein the conductive portion is provided at a position along the one side. The electrophoretic display device according to claim 3, wherein the conductive portion is provided at a corner of the element substrate in a plan view. The electrophoretic display device according to claim 1, wherein a plurality of the conductive portions are provided. The electrophoretic display device according to claim 5, wherein at least two of the plurality of conductive portions are electrically connected. The electrophoresis according to any one of claims 1 to 6, wherein the control circuit outputs a voltage for erasing display on the display area to the conduction unit based on a predetermined signal. Display device. The electrophoretic display device according to claim 7, further comprising an input switch for inputting the predetermined signal to the control circuit. A detector for detecting an impact on the control circuit;
The electrophoretic display device according to claim 7, wherein the predetermined signal is a signal based on a detection result by the detection unit. A method for driving an electrophoretic display device including an electrophoretic layer between a transparent substrate having a common electrode formed on one surface and an element substrate having a pixel electrode,
Causing a potential difference between the common electrode and the pixel electrode to display an image on a display region including a region where the pixel electrode is formed in a plan view;
Erasing an image displayed in the display area by applying a rectangular wave that periodically repeats a first potential and a second potential higher than the first potential to the common electrode;
A method for driving an electrophoretic display device, comprising:   The method for driving an electrophoretic display device according to claim 10, wherein in the step of erasing the image, the pixel electrode has high impedance.

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