JP2009157344A - Driving method of electrophoretic display device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide the driving method of an electrophoretic display device capable of sequential display. <P>SOLUTION: A first control line and a second control line are controlled to suppress the leak current between pixels, so that reliability of a product can be improved. In addition, according to this invention, since electrophoretic elements are driven by causing a potential difference between electrodes, it is possible to change display in accordance with data input. Therefore, it is possible to sequentially display images without heavily increasing a circuit scale. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a method for driving an electrophoretic display device.

    The electrophoretic display device includes a plurality of first electrodes (pixel electrodes), a second electrode opposed to the plurality of first electrodes, and an electrophoretic element sandwiched between the electrodes. In order to display an image on the electrophoretic display device, an image signal is temporarily stored in the memory circuit via the switching element. When an image signal stored in the memory circuit is input to the first electrode and a potential is applied to the first electrode, a potential difference is generated between the second electrode to which a predetermined potential is applied. As a result, the electrophoretic element can be driven to display an image.

As the memory circuit, an SRAM system using an SRAM (Static Random Access Memory), a DRAM (Dynamic Random Access Memory) system using a capacitor, or the like is used (for example, see Patent Document 1).
JP 2003-84314 A Japanese Patent Application No. 2007-087666

  In order to display an image on the electrophoretic display device, it is necessary to provide a sufficient potential difference between the electrodes sandwiching the electrophoretic element to move the electrophoretic particles to one of the electrodes. The voltage required 10V or more. At this time, if different colors are displayed in adjacent pixels, different potentials are input to the first electrodes (pixel electrodes) of the adjacent pixels.

  Therefore, since a large potential difference is generated between the adjacent first electrodes, a leak current may be generated between the adjacent first electrodes via an adhesive or the like that fixes the electrophoretic element to the substrate. there were. Even if the current value per pixel is small, the leakage current is large for the entire display unit of the electrophoretic display device, leading to an increase in power consumption.

  In addition, there is a concern that the first electrode may cause a chemical reaction due to the occurrence of a leak current, which may impair the reliability of the electrophoretic display device. Therefore, it is conceivable to improve the reliability by using a chemically stable and corrosion-resistant material such as gold or platinum for the first electrode. However, in this case, there is a problem that the manufacturing cost increases. there were.

  As means for solving such a problem, the present inventor has proposed an electrophoretic display device capable of controlling the pixel electrode potential by a switch circuit (for example, cited document 2). According to this electrophoretic display device, it is possible to suppress leakage and control display using control lines. The present invention is a further improvement of the electrophoretic display device according to the preceding invention, and enables sequential display using a similar circuit configuration.

  In order to achieve the above object, an electrophoretic display device driving method according to the present invention includes an electrophoretic element including electrophoretic particles sandwiched between a pair of substrates. One electrode is formed, and a second electrode common to the plurality of pixels is formed on the other substrate, and the pixel is connected to a pixel switching element connected to a scanning line and a data line, and to the pixel switching element And a switch circuit provided between the memory circuit and the first electrode, and a first control line and a second control line are connected to the switch circuit. A method of driving an electrophoretic display device, wherein an image signal input step of inputting an image signal to the memory circuit via the pixel switching element is based on an output from the memory circuit. By operating a path, the first control line and the second control line are connected to the first electrode, the potential of the first control line is set to the first potential, and the potential of the second control line is set to the second potential. In this state, the potential of the second electrode is alternately changed to the first potential and the second potential, and in the image display step after the image signal input step, the potential of the first control line is changed to the potential of the first control line. The third potential is higher than the first potential.

  According to the present invention, the first control line and the second control line can be controlled to suppress the leakage current between the pixels and improve the reliability of the product. In addition, according to the present invention, since the electrophoretic element is driven by generating a potential difference between the electrodes, the display can be changed with the progress of data input. Therefore, it is possible to display images sequentially without causing a significant increase in circuit scale. In addition, according to the present invention, after the image signal input step, the potential of the first control line is set to the third potential that is higher than the first potential, so that it is applied between the first electrode and the second electrode. The applied voltage can be made higher. Thereby, even if the contrast is insufficient in the input step, the desired display contrast can be improved.

In the driving method of the electrophoretic display device, the plurality of pixels are arranged in a matrix, and in the image signal input step, the pixels belonging to one line or a plurality of lines of the matrix among the plurality of pixels. The potential of the second electrode is changed in synchronization with the input of the image signal.
According to the present invention, a plurality of pixels are arranged in a matrix, and in the image signal input step, the image signals are input in synchronization with input of image signals for pixels belonging to one line or a plurality of lines of the matrix. Since the potential of the two electrodes is changed, image rewriting is performed for each line or every plurality of lines. For this reason, during data line writing, it is possible to prevent display from being performed with only a part of the pixels belonging to one line or a plurality of lines. In addition, display updating in pixels to which an image signal is input can be performed for each line.

In the driving method of the electrophoretic display device, in the image signal input step, the potential of the first electrode is changed from the second potential to the first potential when the potential of the second electrode is the first potential. When the potential of the second electrode is the second potential, the potential of the first electrode is changed from the first potential to the second potential.
According to the present invention, in the image signal input step, when the potential of the second electrode is the first potential, the potential of the first electrode is changed from the second potential to the first potential. Only when the potential level of the second electrode is changed during the period in which the signal is input, it can be recognized as an image change. Thereby, for example, since the electrophoretic element is not driven during the update of the image signal, it is possible to prevent unintended display.

  In the driving method of the electrophoretic display device according to the present invention, an electrophoretic element including electrophoretic particles is sandwiched between a pair of substrates, a first electrode is formed on each of the substrates for each pixel, and the other A second electrode common to the plurality of pixels is formed on the substrate, the pixel including a pixel switching element connected to a scanning line and a data line, a memory circuit connected to the pixel switching element, A drive circuit for an electrophoretic display device, comprising: a memory circuit; and a switch circuit provided between the first electrode, wherein a first control line and a second control line are connected to the switch circuit. In the image signal input step of inputting an image signal to the memory circuit via the pixel switching element, the switch circuit is operated based on an output from the memory circuit, and the first In the state where the control line or the second control line and the first electrode are connected, the potential of the first control line is set to the first potential, and the potential of the second control line is set to the second potential. The potential of the electrode is set to a potential approximately in the middle between the first potential and the second potential.

  According to the present invention, the first control line and the second control line can be controlled to suppress the leakage current between the pixels, and the reliability of the product can be improved. In addition, since the electrophoretic element is driven by generating a potential difference between the electrodes, the display can be changed with the progress of data input. Therefore, it is possible to display images sequentially without causing a significant increase in circuit scale. In addition, since the potential of the second electrode is set to a substantially intermediate potential between the first potential and the second potential, display of an intermediate gradation such as gray in black and white display can be performed.

The driving method of the electrophoretic display device is characterized in that the potential of the second electrode is changed within a range of ± 30% with respect to an intermediate potential between the first potential and the second potential.
According to the present invention, since the potential of the second electrode is changed within a range of ± 30% with respect to an intermediate potential between the first potential and the second potential, for example, an intermediate gradation such as gray in black and white display Can be displayed. When the potential is intermediate between the first potential and the second potential, the potential balance is the best. Further, if it is in the range of ± 30%, it is possible to adjust according to the characteristics of the electrophoretic display device (ease of white and black).

In the driving method of the electrophoretic display device, the electrophoretic display device is provided with a touch panel, and the image signal changes a potential of the first electrode corresponding to a contact position on the touch panel. And the touch panel signal is input to the memory circuit in the pixel signal input step.
According to the present invention, since the touch panel is provided for the electrophoretic display device capable of sequential display, display rewriting of the electrophoretic display device is performed in real time so as to follow the touch panel signal. Thereby, intuitive display can be performed using a touch panel.

In the driving method of the electrophoretic display device, the touch panel signal includes a first touch panel signal that makes a potential of the first electrode higher than a potential of the second electrode, and a potential of the first electrode that is the second electrode. The second touch panel signal is set to be lower than the potential of the second touch panel signal.
According to the present invention, writing for black display and writing for white display can be switched by the first touch panel signal and the second touch panel signal. As a result, various displays are possible.

In the electrophoretic display device driving method, in the image signal input step, the touch panel signal is input in a state where the potential of the second electrode is the same as the potential of the first control line. And
According to the present invention, it is possible to selectively perform data writing for a portion to be newly written. As a result, power consumption can be reduced, and higher speed writing can be realized.

In the driving method of the electrophoretic display device, a plurality of the scanning lines are arranged along the first direction. In the image signal input step, when the contact position is moved, a plurality of the scanning lines are arranged. On the other hand, the scanning signal is sequentially supplied in the same direction as the moving direction of the contact position.
According to the present invention, scanning can be performed so as to follow the moving direction of the contact position, so that the response of display writing can be improved, and writing can be performed in real time.

In the electrophoretic display device, a plurality of the data lines are arranged along the second direction, and the touch panel signal is supplied simultaneously to the plurality of data lines.
According to the present invention, the time lag from when the contact position is moved to when the display is switched can be shortened as much as possible.

  Hereinafter, the electrophoretic display device 1 according to the present invention will be described with reference to the drawings. FIG. 1 is a configuration diagram of an electrophoretic display device 1 according to an embodiment of the present invention. The electrophoretic display device 1 includes a display unit 3, a scanning line drive circuit (pixel drive unit) 6, a data line drive circuit (pixel drive unit) 7, a common power supply modulation circuit (potential control unit) 8, and a controller 10. ing.

  In the display unit 3, pixels 2 are formed in a matrix of M pieces along the Y-axis direction and N pieces along the X-axis direction. The scanning line driving circuit 6 is connected to the pixel 2 through a plurality of scanning lines 4 (Y1, Y2,..., Ym) extending along the X-axis direction in the display unit 3. The data line driving circuit 7 is connected to the pixel 2 through the display unit 3 via a plurality of data lines 5 (X1, X2,..., Xn) extending along the Y-axis direction. The common power supply modulation circuit 8 is connected to the pixel 2 via the first control line 11, the second control line 12, the high potential power supply line 13, the low potential power supply line 14, and the common electrode power supply line 15. The scanning line driving circuit 6, the data line driving circuit 7, and the common power supply modulation circuit 8 are controlled by the controller 10. The first control line 11, the second control line 12, the high potential power supply line 13, the low potential power supply line 14, and the common electrode power supply wiring 15 are used as a common wiring in all the pixels 2.

Next, a detailed configuration of the pixel 2 will be described with reference to FIG.
As shown in FIG. 2, the pixel 2 includes a driving TFT (pixel switching element) 24, an SRAM (memory circuit) 25, a switch circuit 35, a pixel electrode 21, a common electrode 22, and an electrophoretic element 23. , Is composed of.

  The driving TFT 24 is composed of, for example, an N-MOS (Negative Metal Oxide Semiconductor) transistor, the gate electrode is connected to the scanning line 4, the source electrode is connected to the data line 5, and the drain electrode is a data input terminal of the SRAM 25. Connected to P1.

  The SRAM 25 is a C-MOS (Complementary Metal Oxide Semiconductor) type SRAM, and is composed of two P-MOS (Positive Metal Oxide Semiconductor) transistors 25a and 25b and two N-MOS transistors 25c and 25d. Yes.

  The P-MOS transistor 25a has a source electrode connected to the high potential terminal PH, a drain electrode connected to the data input terminal P1, and a gate electrode connected to the gate electrode of the N-MOS transistor 25c and the data output terminal P2. . The high potential terminal PH is connected to the high potential power line 13.

  The P-MOS transistor 25b has a source electrode connected to the high potential terminal PH, a drain electrode connected to the data output terminal P2, and a gate electrode connected to the gate electrode and the gate input terminal P3 of the N-MOS transistor 25d. .

  N-MOS transistor 25c has a source electrode connected to low potential terminal PL, a drain electrode connected to data input terminal P1, and a gate electrode connected to the gate electrode of P-MOS transistor 25a and data output terminal P2. . The low potential terminal PL is connected to the low potential power line 14.

  N-MOS transistor 25d has a source electrode connected to low potential terminal PL, a drain electrode connected to first data output terminal P2, and a gate electrode connected to the gate electrode of P-MOS transistor 25b and data output terminal P3. Has been. Further, the data input terminal P1 and the data output terminal P3 are connected.

  As described above, the SRAM 25 is a 1-input 1-output memory circuit capable of storing 1-bit image data, and an image signal that defines image data “1” at the data input terminal P1, that is, a high-level image signal. When input, a low level signal is output from the data output terminal P2.

  The switch circuit 35 includes a first transmission gate 36 and a second transmission gate 37. The first transmission gate 36 includes an N-MOS transistor 36a and a P-MOS transistor 36b. The source electrodes of the N-MOS transistor 36a and the P-MOS transistor 36b are connected to the first via a signal input terminal P4. The drain electrodes of the N-MOS transistor 36a and the P-MOS transistor 36b connected to the control line 11 are connected to the pixel electrode 21 via the signal output terminal P5. Further, the gate electrode of the N-MOS transistor 36a is connected to the data output terminal P3 of the SRAM 25, and the gate electrode of the P-MOS transistor 36b is connected to the data output terminal P2 of the SRAM 25.

  The second transmission gate 37 includes an N-MOS transistor 37a and a P-MOS transistor 37b, and the source electrodes of the N-MOS transistor 37a and the P-MOS transistor 37b are connected to the second via a signal input terminal P6. The drain electrodes of the N-MOS transistor 37a and the P-MOS transistor 37b connected to the control line 12 are connected to the pixel electrode 21 via the signal output terminal P7. The gate electrode of the N-MOS transistor 37a is connected to the data output terminal P2 of the SRAM 25, and the gate electrode of the P-MOS transistor 37b is connected to the data output terminal P3 of the SRAM 25.

  When image data “1” is stored in the SRAM 25 and a low level signal is output from the data output terminal P2, the first transmission gate 36 is turned on and supplied to the signal input terminal P4 via the first control line 11. The first driving signal S1 is supplied from the signal output terminal P5 to the pixel electrode 21. On the other hand, when image data “0” is stored in the SRAM 25 and a high level signal is output from the data output terminal P2, the second transmission gate 37 is turned on, and the signal input terminal P6 is connected via the second control line 12. The second drive signal S2 supplied to the pixel electrode 21 is supplied from the signal output terminal P7.

  The pixel electrode 21 is made of Al (aluminum) or the like and applies a voltage to the electrophoretic element 23. The pixel electrode 21 is electrically connected to the signal output terminal P5 of the first transmission gate 36 and the signal output terminal P7 of the first transmission gate 37. Connected. The common electrode 22 functions as a counter electrode of the pixel electrode 21 and is a transparent electrode formed of MgAg (magnesium silver), ITO (indium tin oxide), IZO (indium zinc oxide), or the like. The common potential Vcom is supplied. The electrophoretic element 23 is sandwiched between the pixel electrode 21 and the common electrode 22, and displays an image by an electric field generated by a potential difference between the pixel electrode 21 and the common electrode 22.

  FIG. 3 is a partial cross-sectional view of the electrophoretic display device 1 in the display unit 3. The electrophoretic display device 1 has a configuration in which an electrophoretic element 23 formed by arranging a plurality of microcapsules 40 is sandwiched between an element substrate 28 and a counter substrate 29.

  In the display unit 3, a plurality of pixel electrodes 21 are arrayed on the electrophoretic element 23 side of the element substrate 28, and the electrophoretic elements 23 are bonded to the pixel electrodes 21 through an adhesive layer 30. A common electrode 22 having a planar shape facing the plurality of pixel electrodes 21 is formed on the counter substrate 29 on the electrophoretic element 23 side, and the electrophoretic element 23 is provided on the common electrode 22.

  The element substrate 28 is a substrate made of glass, plastic, or the like, and is not necessarily transparent because it is disposed on the side opposite to the image display surface. Although not shown, between the pixel electrode 21 and the element substrate 28, the scanning line 4, the data line 5, the pixel switching element 24, the latch circuit 25, the switch circuit 35, and the like shown in FIGS. Is formed.

  The counter substrate 29 is a substrate made of glass, plastic, or the like, and is a transparent substrate because it is disposed on the image display side. The common electrode 22 formed on the counter substrate 29 is formed using a transparent conductive material such as MgAg (magnesium silver), ITO (indium tin oxide), IZO (indium zinc oxide) or the like.

  The electrophoretic element 23 is generally formed in advance on the counter substrate 29 side and is handled as an electrophoretic sheet including the adhesive layer 30. A protective release paper is attached to the adhesive layer 30 side.

  In the manufacturing process, the display unit 3 is formed by attaching the electrophoretic sheet from which the release paper is peeled off to the separately manufactured element substrate 28 on which the pixel electrode 21 and the circuit are formed. Yes. For this reason, the adhesive layer 30 exists only on the pixel electrode 21 side.

  FIG. 4 is a schematic cross-sectional view of the microcapsule 40. The microcapsule 40 has a particle size of, for example, about 50 μm and encloses therein a dispersion medium 41, a plurality of white particles (electrophoretic particles) 42, and a plurality of black particles (electrophoretic particles) 43. It is a spherical body. As shown in FIG. 3, the microcapsule 40 is sandwiched between the common electrode 22 and the pixel electrode 21, and one or a plurality of microcapsules 40 are arranged in one pixel 20.

  The outer shell (wall film) of the microcapsule 40 is formed using a transparent polymer resin such as an acrylic resin such as polymethyl methacrylate or polyethyl methacrylate, a urea resin, or gum arabic.

  The dispersion medium 41 is a liquid that disperses the white particles 42 and the black particles 43 in the microcapsules 40. Examples of the dispersion medium 41 include water, alcohol solvents (methanol, ethanol, isopropanol, butanol, octanol, methyl cellosolve, etc.), esters (ethyl acetate, butyl acetate, etc.), ketones (acetone, methyl ethyl ketone, methyl isobutyl ketone, etc.). ), Aliphatic hydrocarbons (pentane, hexane, octane, etc.), alicyclic hydrocarbons (cyclohexane, methylcyclohexane, etc.), aromatic hydrocarbons (benzene, toluene, benzenes having a long-chain alkyl group ( Xylene, hexylbenzene, hebutylbenzene, octylbenzene, nonylbenzene, decylbenzene, undecylbenzene, dodecylbenzene, tridecylbenzene, tetradecylbenzene)), halogenated hydrocarbons (methylene chloride, chloroform, tetrachloride) Element, and 1,2-dichloroethane), can be exemplified a carboxylate, it may be other oils. These substances can be used alone or as a mixture, and a surfactant or the like may be further blended.

  The white particles 42 are particles (polymer or colloid) made of a white pigment such as titanium dioxide, zinc white, and antimony trioxide, and are used, for example, by being negatively charged. The black particles 43 are particles (polymer or colloid) made of a black pigment such as aniline black or carbon black, and are used, for example, by being positively charged.

  These pigments include electrolytes, surfactants, metal soaps, resins, rubbers, oils, varnishes, compound charge control agents, 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.

Next, with reference to FIG. 1, FIG. 2, FIG. 5 and FIG. 6, the driving method of the electrophoretic display device 1 of the present invention and the operation of the electrophoretic element 23 will be described.
FIG. 5 is a timing chart showing a driving method of the electrophoretic display device 1. FIG. 6 is a diagram for explaining specific operations of the white particles 42 and the black particles 43 in the driving method shown in FIG.

  In the following description, among the pixels 20 arranged in the display unit 3, a pixel 20B that is displayed in black and a pixel 20W that is displayed in white will be described. Therefore, in FIG. 5 and FIG. 6, for convenience of explanation, each symbol is indicated by subscripts “B” and “W”, and these subscripts indicate whether the constituent element belongs to the pixel 20B or 20W. There is no other intention.

FIG. 5 shows the temporal potentials of the scanning line 4, the high potential power supply line 13, the low potential power supply line 14, the common electrode 22, the pixel electrode 21B of the pixel 20B, and the pixel electrode 21W of the pixel 20W shown in FIG. It shows a change. In FIG. 5, V _g is the potential of the scanning line 4, V _DD is the potential of the high potential power line 13, V _SS is the potential of the low potential power line 14, V _com is the potential of the common electrode 22, and V _B is the potential of the pixel electrodes 21B, _{V W} represents the potential of the pixel electrode 21W, respectively. “HiZ” in FIG. 5 represents a high impedance state that is electrically disconnected.

FIG. 6 shows how the white particles 42 and the black particles 43 move in the black display pixel 20B and the white display pixel 20W, respectively.
Hereinafter, the high level and low level potentials will be described specifically, but these potential values are examples and can be changed as appropriate.

  First, in step S11 shown in FIG. 5, each wiring of the pixel 20 is electrically connected to the drive circuit so that a signal can be input. Specifically, a low level (0 V) is input to the scanning line 4, a high level (4 V) is supplied to the high potential power supply line 13, and a low level (0 V) is supplied to the low potential power supply line 14. As a result, the latch circuit 25 is turned on, and the image data input from the data line 5 can be stored.

  Next, in step S12 (image signal input step), a selection signal (4V high level) is input to the scanning line 4 for a certain period. As a result, the pixel switching element 24 is turned on, image data is input from the data line 5 to the latch circuit 25, and the latch circuit 25 stores the input image data. In the pixel 20B displayed in black, a low level is input as image data, a high level is output from the output terminal P2 of the latch circuit 25, and the second transmission gate 37 is turned on. Thereby, the high level (4 V) of the second control line 12 is applied to the pixel electrode 21B.

  On the other hand, in the pixel 20W displayed in white, a high level is input as image data, a low level is output from the output terminal P2 of the latch circuit 25, and the first transmission gate 36 is turned on. Thereby, the low level (0 V) of the first control line 11 is applied to the pixel electrode 21W.

  Thereafter, in step S13, the potential of the high potential power supply line 13 is raised from 4V to 20V. The potential of the low potential power supply line 14 remains 0V. Thereby, in the pixel 20B displayed in black, the potential output from the output terminal P2 of the latch circuit 25B rises to a high level (20V). In the pixel 20B displayed in black, a low level is input as image data, a high level is output from the output terminal P2 of the latch circuit 25, and the second transmission gate 37 is turned on. As a result, the high level (20V) of the second control line 12 is applied to the pixel electrode 21B, and the potential of the pixel electrode 21B rises from 4V to 20V. Note that, in the pixel 20W that displays white, a high level is input as image data, a low level is output from the output terminal P2 of the latch circuit 25, and the first transmission gate 36 is turned on. Thereby, the low level (0 V) of the first control line 11 is applied to the pixel electrode 21W. Therefore, the potential applied to the pixel electrode 21W remains low and does not vary.

  In step S13, a rectangular reference pulse that repeats a low level (0 V) period and a high level (20 V) period is input to the common electrode 22 for a plurality of periods (four periods in the figure). Hereinafter, such a driving method is referred to as “common swing driving”. The common swing drive is defined as a drive method in which a pulse that repeats a high level (H) period and a low level (L) period is applied to the common electrode 22 for at least one cycle in a period during which a display image is rewritten. That is.

  According to this common swing driving method, the potential applied to the pixel electrode and the common electrode can be controlled by binary values of a high level (H) and a low level (L). The configuration can be simplified. Further, when a TFT (Thin Film Transistor) is used as the switching element of each pixel electrode 21 (21B, 21W), there is an advantage that the reliability of the TFT can be secured by low voltage driving.

  When the image display operation in step S13 ends, the process proceeds to step S14. In step S14, the high potential power supply line 13, the low potential power supply line 14, and the scanning line 4 are in a high impedance state, and each circuit is in an off state. Accordingly, the pixel electrodes 21W and 21B are also in a high impedance state.

  Through the above steps S11 to S14, white display and black display in each pixel 20 can be performed. In addition, the display image can be sequentially updated by repeating steps S11 to S14.

  In the present embodiment, in addition to the driving method described above, while the selection signal (4V high level) is input to the scanning line 4 in step S12, the common electrode 22 has a low level (0V) period and a high level (4V). An operation of inputting a rectangular reference pulse repeating a period for a plurality of periods is performed. The operation of the pixel 20B and the pixel 20W at this time will be described with reference to the operation of the pixel 20B and the pixel 20W during the common swing operation.

First, the operation of the pixels 20B and 20W in the common swing drive will be described with reference to FIG.
FIG. 6A shows a mode when the low level (L; 0 V) of the first cycle pulse in the common swing drive is applied to the common electrode 22. In the pixel 20B, a high level (H; 20V) is applied to the pixel electrode 21B, and a low level (L; 0V) is applied to the common electrode 22. Accordingly, a vertical electric field is formed between the pixel electrode 21 </ b> B and the common electrode 22, and the positively charged black particles 43 are attracted to the common electrode 22. On the other hand, the negatively charged white particles 42 are attracted to the pixel electrode 21B. At this time, in the pixel 20W, since the common electrode 22 and the pixel electrode 21W are both at a low level (L; 0V), an electric field is not formed between these electrodes, and thus each particle does not move.

  FIG. 6B shows a mode when a high level (H; 20 V) in the first cycle pulse is applied to the common electrode 22. In the pixel 20 </ b> W, a low level (0 V) is applied to the pixel electrode 21 </ b> W, and a high level (20 V) is applied to the common electrode 22. Therefore, a vertical electric field is formed between the pixel electrode 21 </ b> W and the common electrode 22, and the negatively charged white particles 42 are attracted to the common electrode 22. On the other hand, the positively charged black particles 43 are attracted to the pixel electrode 21W. At this time, in the pixel 20B, since both the common electrode 22 and the pixel electrode 21B are at a high level (20 V), an electric field is not formed between these electrodes, and thus each particle does not move.

  FIG. 6C shows a mode immediately after a pulse of one period in the common swing drive is applied. In the pixel 20B, since the black particles 43 gather on the common electrode 22 side and the white particles 42 gather on the pixel electrode 21B side, black display on the common electrode 22 side serving as a display surface is observed. In the pixel 20W, the white particles 42 gather on the common electrode 22 side and the black particles 43 gather on the pixel electrode 21W side, so that white display on the common electrode 22 side serving as a display surface is observed.

  The above is the driving mode in one cycle pulse. By performing this driving for a plurality of cycles, the movement of the white particles 42 and the black particles 43 can be performed more reliably, so that the contrast can be increased. Note that the number and frequency of the common swing drive are preferably determined as appropriate according to the specifications and characteristics of the electrophoretic element. Further, by replacing the pigments used for the white particles 42 and the black particles 43 with pigments such as red, green, and blue, for example, red, green, and blue can be displayed on the display unit 3.

  On the other hand, in the operation of inputting a rectangular reference pulse that repeats a low level (0 V) period and a high level (4 V) period to the common electrode 22 in a plurality of cycles in step 12, When the potential of the common electrode 22 to which 0 is input is 0 V, a potential difference is generated between the pixel electrode 21B and the common electrode 22, the black particles 43 are attracted to the common electrode 22, and the white particles 42 are attracted to the pixel electrode 21B. Gravitate. As a result, black is displayed on the pixel 20B. In addition, in synchronization with the sequential selection of the scanning lines Y1, Y2,..., Ym, the display of the pixels for which the image signal has been written is updated (sequential display). In this driving, since the potential difference between the pixel electrode 21B and the common electrode 22 is smaller than that in step S14 and the generated electric field is weak, the movement of the black particles 43 and the white particles 42 is performed more slowly than in step S13. . As a result, a gray close to black is displayed instead of a complete black, but the display is performed to the extent that it can be visually recognized as black.

  For the pixel 20 </ b> W, when the potential of the common electrode 22 to which a pulse signal is input is 4 V, a potential difference is generated between the pixel electrode 21 </ b> W and the common electrode 22, and white particles 42 are generated in the common electrode 22. The black particles 43 are attracted to the pixel electrode 21W. As a result, white is displayed on the pixel 20B. In synchronization with the sequential selection of the scanning lines Y1, Y2,..., Ym, the display of the pixels for which the image signal has been written is updated (sequential display). In this driving, since the potential difference between the pixel electrode 21W and the common electrode 22 is smaller than that in step S13 and the generated electric field is weak, the movement of the white particles 42 and the black particles 43 is performed more slowly than in step S14. Is called. As a result, not a perfect white color but a gray color close to a white color is displayed, but the display is performed to the extent that it is visible as white.

(Rewriting display color)
Next, an operation for rewriting the color displayed in each pixel will be described.
FIG. 7 is a plan view schematically showing three adjacent pixels 2X to 2Z among the pixels 2 arranged in the display unit 3. FIG. In the present embodiment, as shown in FIG. 7, the pixel 2X displays white (W), the pixel 2Y displays white, and the pixel 2Z displays black (B) (hereinafter referred to as “state (1)”). ) To a state where the pixel 2X is white, the pixel 2Y is black, and the pixel 2Z is white (hereinafter referred to as “state (2)”).

FIG. 8 is a diagram illustrating waveforms of signals supplied to the common electrode 22 and signals supplied to the pixels 2X to 2Z during the image signal input period.
As shown in the drawing, a high level signal (H) and a low level signal (L) are continuously supplied to the common electrode 22 at regular intervals ( _Vcom ). In the pixel 2X, the white display is kept from the state (1) to the state (2). Therefore, a low-level signal is continuously supplied to the pixel electrode belonging to the pixel 2X (V _X ).

In the pixel 2Y, the display is changed from the white display to the black display from the state (1) to the state (2). Therefore, the pixel electrode belonging to the pixel 2Y is changed from a state where a low level signal is supplied to a state where a high level signal is supplied (V _Y ). The timing for changing the signal is preferably within a period in which the signal supplied to the common electrode 22 is at a high level, as shown in FIG.

Switching the signal V _Y supplied to the pixel electrode in this period from the low-level signal to the high level signal, when the signal supplied to the common electrode 22 is switched from the high level signal to a low-level signal A potential difference is generated between the common electrode 22 and the pixel electrode of the pixel 2Y. Due to the potential difference, the black particles 43 are attracted to the common electrode, and the white particles 42 are attracted to the pixel electrode, so that the pixel 2Y has a black display.

In the pixel 2Z, the display is changed from the black display to the white display from the state (1) to the state (2). Therefore, the pixel electrode belonging to the pixel 2Z is changed from a state in which a high level signal is supplied to a state in which a low level signal is supplied (V _Z ). The timing for changing the signal is preferably within a period in which the signal supplied to the common electrode 22 is at a low level, as shown in FIG.

Switching the signal V _Z, which is supplied to the pixel electrode in this period from the high-level signal to a low level signal, when the signal supplied to the common electrode 22 is switched from the low level signal to the high level of the signal A potential difference is generated between the common electrode 22 and the pixel electrode of the pixel 2Z. Due to the potential difference, the black particles 43 are attracted to the pixel electrode, and the white particles 42 are attracted to the common electrode 22, so that the pixel 2Z has a white display.

  When the entire display unit is viewed, an image signal for updating only the pixel whose pixel electrode changes from the low level to the high level is written during the period in which the common electrode 22 is at the high level. During the period when the common electrode 22 is at the low level, an image signal for updating the pixel whose pixel electrode changes from the high level to the low level is written. Therefore, an image signal for performing black display is input when the common electrode 22 is at a high level, and an image signal for performing white display is input when the common electrode 22 is at a low level.

  As described above, according to the present embodiment, the first control line 11 and the second control line 12 can be controlled to suppress the leakage current between the pixels 2 and improve the reliability of the product. In addition, according to the present embodiment, in the image signal input period in which an image signal is input to the SRAM 25 via the driving TFT 24, the switch circuit 35 is operated based on the output from the SRAM 25, and the first control line 11 and the first control line 11 2 The control line 13 and the pixel electrode 21 are connected, the potential of the first control line 11 is set to the high level, and the potential of the second control line 12 is set to the low level. Since the levels are alternately changed, it is possible to display images sequentially without causing a significant increase in circuit scale.

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, as shown in FIGS. 9 and 10, the potential of the common electrode 22 is changed in synchronization with the input of image signals for the pixel groups Y1 to Y9 belonging to one line of the matrix among the pixels 2 of the display unit. It doesn't matter. 9 and 10 show a part of the display portion (pixel groups Y1 to Y9) for the convenience of display, and the extending direction of the scanning lines is the vertical direction in the drawing. (Horizontal direction in FIG. 1). The pixel groups Y1 to Y9 correspond to the reference numerals of the scanning lines in FIG. For example, FIG. 9 shows a state in which image signals are input to the SRAMs of the pixels belonging to the pixel groups Y1 to Y5. In the figure, a low level signal is supplied to the common electrode 22.

  On the other hand, as shown in FIG. 10, a high level signal is supplied to the common electrode 22 in synchronization with the input of the image signal to the SRAM of the pixels belonging to the pixel group Y6. 9 and 10 show only the case of the pixel group Y6, but the same driving is performed for the other pixel groups among the pixel groups Y1 to Y9. By this driving, the high level and the low level of the common electrode 22 change for each of the pixel groups Y1 to Y9, so that image rewriting is performed for each of the pixel groups Y1 to Y9. However, the change from white to black is displayed when the common electrode 22 becomes high level after writing the image signal, and the change from black to white is displayed when the common electrode 22 becomes low level after writing the image. The Therefore, it seems that two lines of Y1 to Y9 are updated. Further, the pixel group belonging to a plurality of lines among the pixels 2 of the display unit may be synchronized with the input of the image signal.

Further, as shown in FIG. 11, the potential of the common electrode 22 may be fixed within a range of ± 30% with respect to an intermediate potential between the high level potential and the low level potential supplied to the pixel electrode 21. good. In the case of FIG. 11, the signal (V _com ) supplied to the common electrode 22 is fixed in a range where V1 = V2, V3 ≦ 0.3 × V1, and V4 = 0.3 × V2. Thereby, for example, intermediate gray scale display such as gray in monochrome display can be performed. Further, if it is in the range of ± 30%, it is possible to adjust according to the characteristics of the electrophoretic display device (ease of white and black).

  Note that the potential of the common electrode 22 is not limited to a range within ± 30% with respect to the intermediate potential, and may be a potential between the high level (H) and the low level (L). . In this case, the potential balance is the best.

(Electronics)
Next, an electronic apparatus according to the present invention will be described.
FIG. 12A is a front view of a wristwatch 401 provided with the electrophoretic display device 1 according to the present invention.

  The wristwatch 401 includes a watch case 402 and a pair of bands 403 connected to the watch case 402. On the front face of the watch case 402, a display device 405 including the electrophoretic display device 1 according to the present invention, a second hand 421, a minute hand 422, and an hour hand 423 are provided. On the side surface of the watch case 402, a crown 410 as an operation element and an operation button 411 are provided.

  FIG. 12B is a side sectional view of the wrist watch 401. Inside the watch case 402, a housing portion 402A is provided. A movement 404 and a display device 405 are accommodated in the accommodating portion 402A. A transparent cover 407 made of glass or resin is provided at one end side (front side of the timepiece) of the accommodating portion 402A. A back cover 409 is screwed to the other end side (the back side of the watch) of the accommodating portion 402 </ b> A 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 consisting of a second hand 421, a minute hand 422 and an hour hand 423 are connected. This hand movement mechanism rotates the analog hands 421 to 423 and functions as a time display unit for displaying the set time.

  The display device 405 is disposed on the timepiece front side of the movement 404 and constitutes a display unit of the wristwatch 401. The display surface of the display device 405 has a circular shape here, but may have another shape such as a regular octagonal shape or a hexagonal shape. A through-hole 405 </ b> A that penetrates the front and back of the electrophoretic display device 405 is formed at the center of the electrophoretic display device 405. The shafts of the second wheel 424, second wheel 425 and hour 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 electrophoretic display device of the present invention can also be applied to electronic devices other than watches.
FIG. 13 is a perspective view illustrating a configuration of the electronic paper 500. The electronic paper 500 includes the electrophoretic display device of the present invention as the display unit 501. The electronic paper 500 has flexibility, and includes a main body 502 formed of a rewritable sheet having the same texture and flexibility as conventional paper.

  FIG. 14 is a perspective view showing the configuration of the electronic notebook 600. An electronic notebook 600 is obtained by bundling a plurality of electronic papers 500 shown in FIG. The cover 601 includes display data input means (not shown) for inputting display data sent from an external device, for example. Thereby, according to the display data, the display content can be changed or updated while the electronic paper is bundled.

  The wristwatch 401, the electronic paper 500, and the electronic notebook 600 described above include the electrophoretic display device of the present invention, and thus have a highly reliable display unit.

[Pen input device (1)]
Next, another embodiment of the present invention will be described. In the present embodiment, a case where an electrophoretic display device is mounted on an information processing system 1000 including a pen input device will be described. In the present embodiment, a process when the display of the entire screen of the electrophoretic display device is changed by a pen input device will be described.

  FIG. 15 is a diagram for explaining the information processing system 1000 according to the present embodiment. The illustrated configuration includes a host device 703 and a client device 701 that is used for displaying and operating processing results of the host device 703. In the present embodiment, the host device 703 and the client device 701 can be connected with an operation, and a plurality of client devices 701 can be used alternately. In the host device 703, processing is advanced by an event driven type accompanying an operation to the client device 701.

  In addition, the present embodiment includes a communication unit that transmits and receives signals between the host device and the client device. The communication means of the present embodiment includes operation buttons 109a, 109b, and 109c, a pen 702 that is a wireless or wired contact on the host device 703 side, and a contact member that contacts the operation buttons 109a to 109c, and a client device 701 described later. And a processing unit 103. The processing unit 103 outputs communication information corresponding to the touched operation button when touching the operation buttons 109a, 109b, and 109c.

  In the present embodiment, the client device 701 and the host device 703 are configured to communicate with each other when the pen 702 contacts (touch) the operation buttons 109a, 109b, and 109c. However, the present embodiment is not limited to the one that communicates by touching, and may be configured such that communication is ensured when both approach each other over a very short predetermined distance.

  Further, the communication between the client device 701 and the host device 703 is not limited to that via the operation buttons 109a to 109c and the pen 702, but the two are always connected using a communication cable or using a wireless LAN or the like. May be able to communicate.

  Hereinafter, the client device 701 and the host device 703 will be described.

(Client device)
The client device 701 includes a thin display and a relatively simple device for displaying an image (including characters and drawings) on the display. In the present embodiment, the configuration including the display and the device is hereinafter referred to as electronic paper.

  The client device 701 includes a memory display 101 that functions as a display. The electrophoretic display device 1 described above is preferably used as the memory display body 101. Further, in the present embodiment, a transparent touch panel 180 is provided on the memory display body 101. As the transparent touch panel 180, for example, it is conceivable to employ a resistive film type configuration in which a grid electrode is provided on the memory display body 101 and a change in electrical resistance caused by energization at a point touched by an operator is detected.

  Further, the touch panel 180 includes a generation unit that generates ultrasonic waves and infrared light on the memory-type display body 101, and a change in ultrasonic waves and infrared light that occurs when the pen 702 or the like touches or approaches the transparent touch panel 180. It is also conceivable to use an ultrasonic surface acoustic wave method or an infrared light shielding method that detects a point designated by an operator by shielding an ultrasonic wave or infrared light. Furthermore, a capacitance method that detects a touch by a change in capacitance that occurs when the operator touches the memory-type display body 101 with a finger can be employed.

  In the present embodiment, a point indicating a position detected on the transparent touch panel 180 is hereinafter referred to as a touch point.

  Such a transparent touch panel 180 functions as a position detection unit of the client device 701 that detects a position designated on the memory display body 101 of the present embodiment. In addition, the position designated on the display in the present embodiment is not limited to the point designated directly on the memory display 101, and is separate from the memory display 101, And the position designated by the touch panel in which the coordinate corresponding to the coordinate on the memory | storage property display body 101 was set is also included.

  In addition, the position detection unit of the present embodiment can use a transparent touch panel having a configuration different from any of the transparent touch panels described above. However, particularly high accuracy is not required for position detection on the client device 701 side. Therefore, regarding the method of the transparent touch panel, the detection accuracy and the size, cost, and weight reduction of the device should be considered together.

  On the other hand, the operation buttons 109 a, 109 b, and 109 c of the client device 701 are provided corresponding to the type of operation performed by the operator on the client device 701. The type of operation refers to, for example, rewriting (page turning) of the screen displayed on the memory display 101.

  The operation buttons 109a to 109c also serve as a communication interface between the client apparatus 701 and the host apparatus 703 together with a pen 702 of the host apparatus 703 described later. As a local communication method between the operation buttons 109a to 109c and the pen 702, a method using light such as infrared rays, a method using electromagnetic waves, a method using electromagnetic induction, and the like can be considered. In the present embodiment, description will be made based on a method using light.

  That is, the operation buttons 109a to 109c include an optical communication module including an infrared light receiving / emitting unit. The pen 702 includes an infrared irradiation unit that irradiates infrared rays, an infrared reception unit that receives reflected light of the irradiated infrared rays, and an imaging optical system that forms an image of the reflected light on the infrared reception unit.

  Further, the operation buttons 109a to 109c and the pen 702 are provided with a coil (electromagnetic coupling unit (power transmission unit, power reception unit) for feeding power). The pen 702 is lightly pressed (touched) on the operation buttons 109a to 109c. Thus, both antenna coils are electromagnetically coupled, and power is supplied from the pen 702 and the host device 703 side to the client device 701. Next, the optical communication module of the operation buttons 109a to 109c and the infrared irradiation of the pen 702 In this embodiment, communication information corresponding to the signal generated by the processing unit 103 is generated, and the pen 702 is generated. The communication information is delivered to the host device 703 via

  In the present embodiment in which information input / output between the client device 701 and the host device 703 is performed by infrared rays, lower power consumption and higher speed communication (16 Mbps, etc.) are possible compared to the case of electromagnetic induction. become. In addition, it is possible to suppress the influence on communication when the electromagnetic coupling is provided to supply power to the client device 701.

  In this embodiment, communication is enabled by touching the operation buttons 109a to 109c, but communication between the host and the client is not started by touching on the client device 701 other than the operation buttons 109a to 109c. In such a touch on an arbitrary position on the memory-type display body 101 of the client device 701, only position detection and storage of the result are performed.

  That is, in the present embodiment, a coordinate pattern (position information code) is set in advance on the memory display body 101, the pattern is illuminated by the infrared irradiation unit, and the coordinate pattern of the memory display body 101 is optically transmitted by the infrared reception unit. Can be read. According to such a configuration, in this embodiment, the host device 703 can read the coordinates on the memory-type display body 101 touched with the pen 702.

  In addition, the client device 701 includes a nonvolatile storage unit 102 and a processing unit 103 as a configuration for storing display data and executing display. The nonvolatile storage unit 102 can include document data 105, processing state data 106, and a reaction map 111 in addition to the display data 104. The display data 104 is data to be displayed as a result of processing the document data 105 by the host device 703, and is received from the host device 703 and displayed on the memory display body 101. The processing status data 106 is data that records the processing of the document data 105 performed in the host device 703 at this time, and includes processing context information to be referred to when the processing is continued. Furthermore, the reaction map 111 includes commands associated with the operation buttons 109a, 109b, and 109c, document elements and dialog elements (character strings, images, link information) displayed at the coordinates of the memory display 101. The execution instruction) is provided so that the client apparatus 701 can extract the reaction to be performed in response to the operation without reproducing the processing state of the host apparatus 703 and can instruct the host apparatus 703 to execute the reaction. ing. Note that the reaction map 111 includes two types of reaction maps relating to predetermined instructions assigned to the operation buttons 109a to 109c and reaction maps relating to document element extraction. The reaction map related to a predetermined instruction instructs execution of a predetermined operation, while the reaction map related to extraction of a document element is a document element or dialog element (corresponding to each coordinate position of the memorized display 101) ( Character string, image, link information, execution instruction).

  The processing unit 103 of the client device 701 includes a display execution unit 108 and a reaction extraction unit 112. The display execution unit 108 directly controls the storage display 101 in accordance with the update of the display data 104 stored in the nonvolatile storage unit 102 and causes the storage display 101 to display the updated display data 104. Specifically, the display execution unit 108 refers to the display data 104 and drives the X driver and Y driver of the memory display 101 to display a raster image on the memory display 101.

  In the present embodiment, a TFT (Thin Film Transistor) method can be adopted.

  The reaction extraction unit 112 is displayed on the command or the memory display 101 by comparing one of the operation buttons 109a, 109b, and 109c or the coordinates of the point touched by the pen 702 with the reaction map 111. Extract document element and dialog element data. Then, the extraction result is output to the document processing unit 160 of the host device 703 via the pen 702 and the operation buttons 109a to 109c.

  Furthermore, the client device 701 of this embodiment includes a display control unit 140. The display control unit 140 draws an image based on the position detected by the transparent touch panel 180, a communication interface including the image drawn by the locus processing unit 142, the pen 702, and the operation buttons 109a to 109c. And a combining / separating unit 141 that superimposes an image based on the display data 104 that is image data transmitted in this manner and displays the image on the display.

  In the above configuration, the trajectory processing unit 142 functions as a client-side image drawing unit, and the combining / separating unit 141 functions as a client-side image combining unit.

  The trajectory processing unit 142 draws a line or the like by changing the pixel of the memory display corresponding to the touch point detected by the transparent touch panel 180 to the drawing color. An image (line drawing) such as a drawn line is managed as an image (layer image) of a layer different from the display data 104 of the nonvolatile storage unit 102 in the display control unit 140. The synthesizing / separating unit 141 displays the layer image of the line drawing and the layer of the display data 104 by superimposing the layer image of the line drawing by the client device 701 and the layer image of the display data 104 by the host device 703 on the storage display 101. Composite with the image.

  Further, by not displaying either the layer image of the line drawing by the client device 701 or the layer image of the display data 104 by the host device 703 displayed in an overlapping manner, the two can be separated.

  By displaying the line image layer image and the layer image of the display data 104 in an overlapping manner, the present embodiment, for example, gives the operator a feeling of operation such as adding a marker or an annotation on the display data 104 by the host device 703. It becomes possible to give.

  The locus processing unit 142 may have correction information for alignment between the transparent touch panel 180 and the memory display body 101. Further, it is desirable that the composition / separation unit 141 clears the diagram drawn by the locus processing unit 142 when the composite image is confirmed by the host device 703 to be described later, for example, after the end of the input of the continuous locus is confirmed. However, this function is not essential, and may remain until the composite image is updated by the host device 703.

  The trajectory processing unit 142 is not limited to a configuration that draws a line drawing based on a position detected by the transparent touch panel 180, and may draw an image such as a pointer. According to such a configuration, it is possible to quickly indicate the position that the operator is viewing and the execution range of the command even in electronic paper, and to improve the operability of the information processing system.

  Further, the client device 701 includes a secondary battery 131 and an operation unit 132. The secondary battery 131 is a battery for supplying power to each component described above, and the operation unit 132 is a component for inputting an instruction that is directly input to the client device 701 without going through the host device 703. It is.

(Host device)
The host device 703 includes a power supply 190, a document processing unit 160, and an information service unit 170. The host device 703 is configured to generate the display data 104 by the document processing unit 160 and transmit the generated display data 104 to the client device 701 using the pen 702 and the operation buttons 109a to 109c.

  The document processing unit 160 is configured to control the entire information processing system. Therefore, the document processing unit 160 includes a document application program 161, and reads and executes processing routines corresponding to instructions stored in advance according to various processing instructions acquired via the pen 702 and the operation buttons 109a to 109c. . The document application program 161 is a program related to determination of instruction content, reading of a processing routine corresponding to the content, and execution.

  Specifically, for example, when an instruction to display the next page of an image being displayed (page turning) is generated on the memory display 101, the document application program 161 is currently displayed on the memory display 101. The processing status data 106 and the document data 105, which are information related to the page, are acquired from the nonvolatile storage unit 102 via the pen 702 and the operation buttons 109a to 109c. Then, the layout processing for the next page is executed based on the processing state data 106 and the document data 105, and the display data 104 and the reaction map 111 for the next page are generated. Further, a series of processing routines for storing in the nonvolatile storage unit 102 via the pen 702 and the operation buttons 109a to 109c is executed.

  The information service unit 170 is configured to use document data and other network resources that can be transmitted to the client device 701. In addition, the host device 703 includes a position detection unit 150. The position detection unit 150 includes an observation unit 151 and a calculation unit 152. The observation unit 151 detects a coordinate pattern of a point touched by the pen 702 based on the light reception result of the infrared reception unit transmitted from the pen 702. To do. The detected coordinate pattern is output to the calculation unit 152. The calculation unit 152 performs a calculation such as decoding an information graphic with respect to the coordinate pattern, specifies the coordinates of the touch point, and sends the coordinates to the document processing unit 160.

  The document processing unit 160 processes the coordinates of the touch point obtained from the position detection unit 150 in accordance with the processing instruction of the document application program 161. This process varies depending on the document application program to be operated. For example, a process of adding a locus corresponding to a touch point to the document data 105 can be considered. In this case, the document processing unit 160 first stores the coordinates of the touch points obtained sequentially in a temporary memory to prepare for an instruction operation by the operator. When the operator draws a series of trajectories while viewing the composite image on the client device 701 and then touches the operation button 109 corresponding to the confirming operation to reflect the trajectories, the host device 703 indicates that the operation has been performed. Is determined, the corresponding document application program 161 is called, and the document processing unit 160 processes the stored coordinate data string. At this time, the document processing unit 160 generates, for example, display data as a result of adding a locus corresponding to the touch point based on an instruction from the document application program 161, and replaces the layer image generated on the client device 701 side. Are transmitted to the client device 701.

  A composite image generated on the host device 703 side can generally obtain higher image quality than a composite image generated by overlaying layer images. Therefore, in the present embodiment, from the viewpoint of the operability of the operator, the displayed image is later synthesized with higher image quality while the line drawing or the like is quickly displayed on the memory display body 101 in response to the touch of the pen 702. It can be replaced with an image.

  The reason that the image quality of the composite image generated by the host device 703 can be higher than the image quality of the composite image generated by the client device 701 is that the host device 3 is configured for position detection and image processing. The demand for smaller and lighter devices is lower than that of the client device 701.

  In the above configuration, the document processing unit 160 includes the host-side image drawing unit, the host-side image combining unit that generates a combined image by combining the drawn image and the image based on the image data transmitted by the communication unit, After the layer image is displayed on the client device 701 side, the image functions as display control means for displaying on the memory-type display body 101 instead of the layer image.

(Driving method)
Next, the operation of the information processing system 1000 according to the present embodiment and the driving of the memory display 101 will be described. Refer to FIG. 16 for driving of the memory-type display body 101.
When the pen 702 is brought into contact with the touch panel 180, both the host device 703 and the client device 701 are activated and become communicable. At this time, the client device 701 electrically connects each wiring of the pixel 20 in the memory-type display body 101 to the drive circuit (step S11). As shown in step S11 of FIG. 16, a low level (0V) is input to the scanning line 4, a high level (4V) is supplied to the high potential power line 13, and a low level (0V) is supplied to the low potential power line 14. The As a result, the latch circuit 25 is turned on, and the image data input from the data line 5 can be stored (step S11).

  Thereafter, the client device 701 supplies the intermediate level (2V) to the common electrode 22 (step S12). By supplying an intermediate level (2V) to the common electrode 22, the input of the pen 702 or the like is thereafter effective. As shown in FIG. 16, in the present embodiment, it is preferable to set the period of step S12 during which writing with the pen 702 is effective, for example, to be a period of about 20 to 30 frames.

  The host device 703 also detects that the pen 702 has touched the touch panel 180. The position detection unit 150 detects the contact position based on the observation of the infrared light reception signal by the observation unit 151, and detects the coordinates at the position by the calculation unit 152. The detected coordinates are temporarily stored in a buffer or the like (not shown) as data indicating the coordinates of the contact position.

  The host device 703 performs predetermined processing using the coordinate data of the detected position accumulated by the document processing unit 160. As the predetermined process, for example, adding coordinate data to a document can be considered. Then, new display data 104 obtained as a result of the additional writing is transmitted to the client device 701. The client device 701 displays an image reflecting the transmitted display data 104 on the memory-type display body 101. At this time, the image signal input to the memory-type display body 101 includes a touch panel signal. Here, the touch panel signal is a signal corresponding to coordinate data based on the contact position of the pen 702 with respect to the touch panel 180, and is a signal for setting the display at the coordinates of the contact position to black display or white display, for example. Further, the touch panel signal may be a signal for changing the display in the pixels in a certain range centered on the coordinates of the contact position to black display or white display. As a result, an image in a state where the display is added at a position corresponding to the touch position of the touch panel 180 is displayed on the memory-type display body 101.

  When the pen 702 is moved while being in contact with the touch panel 180, the above processing is continuously performed. As a result, a display is added to a portion corresponding to the locus of the contact position on the touch panel 180. In this state, an image is displayed on the memory display 101.

  As described above, according to the information processing system of the present embodiment, it is possible to perform writing in real time on the memory-type display body 101 capable of sequential display. For example, even when the touch panel 180 is provided on the memory display 101 and writing is performed on the touch panel 180 via the pen 702, the display of the memory display 101 is rewritten in real time so as to follow the writing by the pen 702. It will be. This makes it possible to perform an intuitive display as if an image is directly written on the memory display 101 with the pen 702.

  In the present embodiment, since Vcom is set to the intermediate level (2 V), the operation response can be further enhanced. When Vcom is set to an intermediate level (2 V), the voltage applied to the electrophoretic particles 42 and 43 is smaller than that in the above embodiment. Therefore, the use potential at the time of data writing at the time of input by the pen 702 may be made larger than that at the time of normal data writing. For example, the voltage used for normal writing can be 3V, and the voltage used for input with the pen 702 can be 5V.

  In the electrophoretic display device constituting the memory display 101, an afterimage remains if a high voltage is constantly applied. On the other hand, in this embodiment, since the voltage applied when inputting with the pen 702 is suppressed to a low voltage, an afterimage can be reduced. As a result, the period of step S12 during which the input operation of the pen 702 is valid can be extended to, for example, about 20 to 30 frames.

  Further, in this embodiment, by setting Vcom to an intermediate level (2 V), it is possible to write the pen 702 in both black display and white display. In the present embodiment, the touch panel signal when the input of the pen 702 is written in black display corresponds to the first touch panel signal, and the touch panel signal when the input of the pen 702 is written in white display corresponds to the second touch panel signal. Here, the first touch panel signal is a signal that makes the potential of the pixel electrode 21 higher than the potential (Vcom) of the common electrode 22, and the second touch panel signal is the potential of the pixel electrode 21 that is the potential of the common electrode 22 (Vcom). ) Is a lower signal. Whether to display in black or white can be freely set by, for example, providing a switch in the client device 701 and switching the switch.

  In addition, as a timing which starts step S11, although the case where the pen 702 contacts the touch panel 180 is used as a trigger in this embodiment, you may introduce into step S11 by another system.

[Pen input device (2)]
Next, another embodiment of the driving method of the information processing system 1000 including a pen input device will be described. FIG. 17 is a timing chart showing a method for driving the memory display 101 according to the present embodiment. An information processing system 1000 according to this embodiment has the same configuration as the information processing system described in the above embodiment, and is described with the same reference numerals.

  Similar to the embodiment of the information processing system 1000, when the pen 702 is brought into contact with the touch panel 180, both the host device 703 and the client device 701 are activated and become communicable. At this time, the client device 701 electrically connects each wiring of the pixel 20 in the memory-type display body 101 to the drive circuit (step S11).

  Thereafter, the client device 701 supplies a low level (0 V) to the common electrode 22 (step S12). By supplying a low level (0 V) to the common electrode 22, the input of the pen 702 or the like thereafter becomes effective. As shown in FIG. 17, also in this embodiment, it is preferable to set the period of step S12, which is a period during which writing with the pen 702 is effective, to be a period of about 20 to 30 frames, for example.

  The host device 703 detects that the pen 702 has touched the touch panel 180, and generates coordinate data indicating the coordinates of the contact position based on this. The host device 703 transmits this coordinate data as new display data 104 to the client device 701. The image signal based on the display data 104 includes a touch panel signal. The display data 104 is data in which a high level (4 V) potential is input to the pixel electrode 21 corresponding to the coordinates of the contact position, and a low level (0 V) potential is input to the other pixel electrodes 21. Yes.

  Further, when the contact position by the pen 702 moves, the host device 703 detects the moving direction of the contact position on the touch panel 180 based on the coordinates detected by the calculation unit 152. At this time, as the moving direction, it is detected which of the two directions of the arrangement direction of scanning lines 4 (vertical direction in the present embodiment) is. After detecting the moving direction, the host device 703 transmits data relating to the moving direction to the client device 701.

  The client device 701 inputs the transmitted display data 104 to the memory display body 101. As a result, a high level signal is input to the data line 5 connected to the memory circuit 25 corresponding to the coordinates of the contact position, and a low level signal is input to the other data lines 5. When a scanning signal is input in this state, the second control line 12 is connected to the pixel electrode 21 corresponding to the coordinates of the contact position, and a high level is input. Further, the first control line 11 is connected to the other pixel electrode 21, and a low level is input.

  In this embodiment, since the potential Vcom of the common electrode 22 is at a low level, the electrophoretic particles 42 and 43 are not moved in the pixel electrode 21 to which the low level is input. In the pixel electrode 21 to which the high level is input, the black particles 43 move to the common electrode 22 side, and the white particles 42 move to the pixel electrode 21 side. For this reason, an image in which black display is newly added to the pixel 20 corresponding to the coordinates of the contact position is displayed with respect to the image displayed so far.

  At this time, the client device 701 sequentially scans a plurality of scanning lines 4 in the same direction as the movement direction (upward or downward) of the contact position based on the arrangement direction of the scanning lines 4. To supply. For example, as shown in FIG. 18, when the pen 702 is moved upward in the drawing on the touch panel 180, the scanning signal is sequentially supplied upward from the lower side to the upper side in the drawing. By this operation, the contact position is detected and displayed so as to follow the movement of the contact position by the pen 702. Further, when inputting the scanning signal, it is preferable to simultaneously supply scanning signals to a plurality of scanning lines 4 (eight scanning lines in FIG. 18) as shown in FIG. Thereby, the followability with respect to the movement of the contact position of the pen 702 is improved, and the display switching on the memory-type display body 101 is performed more smoothly. The number of scanning lines 4 that simultaneously supply scanning signals is not limited to eight, and may be seven or less or nine or more.

  When the contact position on the touch panel 180 moves, for example, a plurality of coordinate data regarding the contact position is stored in a buffer (not shown), and one display data 104 is generated by the plurality of coordinate data. I do not care. In this case, the high level is supplied to the plurality of data lines 5 collectively. By combining this configuration with the above example that supplies scanning signals to a plurality of scanning lines 4 at the same time, the range of a plurality of lines can be rewritten at the same time in a single scan, so that the time lag of rewriting is minimized. It can be shortened and the display can be rewritten in real time. The number of data lines 5 that simultaneously supply a high level may be the same as or different from the number of scanning lines 4 that simultaneously supply scanning signals, for example.

  As described above, according to the present embodiment, the potential Vcom of the common electrode 22 is set to a low level (0 V) when input with the pen 702 is performed, and the pixel electrode 21 corresponding to the contact position of the touch panel 180 is set to a high level. The other pixel electrodes 21 can selectively write data in a portion to be newly written by inputting a low level. As a result, power consumption can be reduced, and higher speed writing can be realized.

  Further, according to the present embodiment, when the pen 702 is moved on the touch panel 180, the scanning signal is sequentially supplied in a direction that follows the moving direction of the pen 702, so that the scanning response can be further enhanced. It is possible to update the image in real time.

  In the case where the electrophoretic display device 1 is mounted on the information processing system 1000, when the pen 702 is used for input, the potential Vcom of the common electrode 22 repeats a low level (0V) period and a high level (4V) period. You may make it perform the operation | movement which inputs the reference pulse of a shape for several periods.

1 is a configuration diagram of an electrophoretic display device. FIG. 6 illustrates a circuit configuration of a pixel. Sectional drawing of the display part of an electrophoretic display device. The block diagram of a microcapsule. FIG. 10 is a diagram illustrating a timing chart according to a method for driving an electrophoretic display device. The figure explaining operation | movement of an electrophoretic element. The top view of an adjacent pixel. The top view of an adjacent pixel. The figure which shows the mode of a drive of an electrophoretic display apparatus. The figure which shows the mode of a drive of an electrophoretic display apparatus. The figure which shows the signal waveform at the time of the drive of an electrophoretic display apparatus. FIG. 13 is a diagram showing an example of an electronic apparatus including an electrophoretic display device according to the invention. FIG. 13 is a diagram showing an example of an electronic apparatus including an electrophoretic display device according to the invention. FIG. 13 is a diagram showing an example of an electronic apparatus including an electrophoretic display device according to the invention. The figure which shows the structure of the information processing system which concerns on other embodiment of this invention. The timing chart which shows the drive of the memory-type display body which concerns on this embodiment. The timing chart which shows the drive of the memory-type display body which concerns on other embodiment of this invention. The figure which shows the mode of the drive of the memory | storage property display body which concerns on this embodiment.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Electrophoretic display device 2 ... Pixel 3 ... Display part 4 ... Scanning line 5 ... Data line 6 ... Scanning line drive circuit 7 ... Data line drive circuit 8 ... Common power supply modulation circuit 10 ... Controller 11 ... 1st control line 12 ... 2nd control line 13 ... 1st power supply line 14 ... 2nd power supply line 21 ... Pixel electrode 22 ... Common electrode 23 ... Electrophoretic element 24 ... Driving TFT 25 ... SRAM 28 ... Element substrate 29 ... Counter substrate 35 ... Switch circuit 40 DESCRIPTION OF SYMBOLS ... Microcapsule 41 ... Dispersion medium 42 ... White particle 43 ... Black particle 401 ... Wristwatch 500 ... Electronic paper 600 ... Electronic note 101 ... Memory display 180 ... Touch panel 1000 ... Information processing system

Claims (10)

An electrophoretic element including electrophoretic particles is sandwiched between a pair of substrates. A first electrode is formed for each pixel on one of the substrates, and a first electrode common to a plurality of the pixels is formed on the other substrate. Two electrodes are formed, and the pixel is provided between a pixel switching element connected to a scan line and a data line, a memory circuit connected to the pixel switching element, and the memory circuit and the first electrode. An electrophoretic display device in which a first control line and a second control line are connected to the switch circuit,
In an image signal input step of inputting an image signal to the memory circuit via the pixel switching element,
The first control line and the second control line are connected to the first electrode by operating the switch circuit based on the output from the memory circuit,
With the potential of the first control line set to the first potential and the potential of the second control line set to the second potential, the potential of the second electrode is alternately changed to the first potential and the second potential. ,
In the image display step after the image signal input step,
The method for driving an electrophoretic display device, wherein the potential of the first control line is set to a third potential that is higher than the first potential. The plurality of pixels are arranged in a matrix,
In the image signal input step, the potential of the second electrode is changed in synchronization with the input of the image signal for the pixels belonging to one line or a plurality of lines of the matrix among the plurality of pixels. Item 2. A driving method of an electrophoretic display device according to Item 1. In the image signal input step, when the potential of the second electrode is the first potential, the potential of the first electrode is changed from the second potential to the first potential, and the potential of the second electrode is changed to the first potential. The method for driving an electrophoretic display device according to claim 1, wherein the potential of the first electrode is changed from the first potential to the second potential when the potential is two potentials. An electrophoretic element including electrophoretic particles is sandwiched between a pair of substrates. A first electrode is formed for each pixel on one of the substrates, and a first electrode common to a plurality of the pixels is formed on the other substrate. Two electrodes are formed, and the pixel is provided between a pixel switching element connected to a scan line and a data line, a memory circuit connected to the pixel switching element, and the memory circuit and the first electrode. An electrophoretic display device in which a first control line and a second control line are connected to the switch circuit,
In an image signal input step of inputting an image signal to the memory circuit via the pixel switching element,
Operating the switch circuit based on an output from the memory circuit, connecting the first control line or the second control line and the first electrode;
With the potential of the first control line set to the first potential and the potential of the second control line set to the second potential, the potential of the second electrode is set to a substantially intermediate potential between the first potential and the second potential. A method for driving an electrophoretic display device. The driving method of the electrophoretic display device according to claim 4, wherein the potential of the second electrode is changed within a range of ± 30% with respect to an intermediate potential between the first potential and the second potential. . The electrophoretic display device is provided with a touch panel,
The image signal includes a touch panel signal that changes a potential of the first electrode corresponding to a contact position on the touch panel,
The method for driving an electrophoretic display device according to claim 1, wherein in the pixel signal input step, the touch panel signal is input to the memory circuit. The touch panel signal includes a first touch panel signal that makes the potential of the first electrode higher than the potential of the second electrode, and a second touch panel signal that makes the potential of the first electrode lower than the potential of the second electrode; The electrophoretic display device according to claim 6, wherein the electrophoretic display device is selected from any one of the following. The touch panel signal is input in the image signal input step in a state where the potential of the second electrode is the same as the potential of the first control line. Electrophoretic display device. A plurality of the scanning lines are arranged along the first direction,
In the image signal input step, when the contact position is moved, scanning signals are sequentially supplied to the plurality of scanning lines in the same direction as the movement direction of the contact position. The driving method of the electrophoretic display device according to claim 1. A plurality of the data lines are arranged along the second direction,
The method for driving an electrophoretic display device according to claim 9, wherein the touch panel signal is simultaneously supplied to a plurality of the data lines.

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