WO2005104078A1

WO2005104078A1 - Information display drive method

Info

Publication number: WO2005104078A1
Application number: PCT/JP2005/007542
Authority: WO
Inventors: Maki Masutani; Norio Nihei; Shuhei Tsuchie
Original assignee: Bridgestone Corporation
Priority date: 2004-04-21
Filing date: 2005-04-20
Publication date: 2005-11-03
Also published as: EP1758087A1; EP1758087A4

Abstract

For the line electrodes composed of lines of electrodes extending in the line direction on one substrate and the column electrodes composed of columns of electrodes extending in the column direction on the other substrate, information on image of one frame is displayed by applying a voltage while scanning the line electrodes from one end to the other. After one frame is displayed, a voltage for generating crosstalk in a first color and a voltage for generating crosstalk in a second color are applied to all the cells of the display section once or more times. Specifically, two or more lines are added at the end of a scan, and drive for performing a display with the first color and a display with the second color once or more times is performed after one scan (a first invention). Pulse voltages composed of voltages including a drive voltage of the ON state and a voltage of the OFF state lower than the threshold voltage at which the display medium starts moving are applied as drive voltage applied to the electrodes to produce an electric field (a second invention). Further, a pulse is applied a plurality of times when one pixel rewrite is performed, and the drive waveform is adjusted so that the polarity of the crosstalk voltage applied to non-rewritten pixels does not change during one pixel rewrite (a third invention).

Description

Specification

Driving method of information display device

Technical field

[0001] The present invention encapsulates at least two types of display media of a first color and a second color between two opposing substrates, at least one of which is transparent, and applies an electric field to the display medium from the electrodes. Also, the present invention relates to a method for driving an information display device that displays information such as an image by moving a display medium (first invention and second invention).

Further, according to the present invention, a display medium is sealed between two opposing substrates, at least one of which is transparent, an electric field is applied to the display medium from the electrodes, and the display medium is moved to display information such as an image. The present invention relates to a method for driving an information display device (third invention).

Background art

[0002] Hitherto, information display devices using technologies such as an electrophoresis system, an electrochromic system, a thermal system, and a two-color particle rotation system have been proposed as information display devices replacing liquid crystal (LCD). .

[0003] These conventional technologies have advantages such as a wide viewing angle close to ordinary printed matter, low power consumption, and a memory function as compared with LCDs. It is considered as a technology that can be used for various information display devices, and is expected to be applied to information display for mobile terminals and electronic paper. In particular, recently, an electrophoresis method in which a dispersion liquid composed of dispersed particles and a coloring solution is microencapsulated and disposed between opposed substrates has been proposed and expected.

[0004] However, in the electrophoresis method, there is a problem that the response speed is reduced due to the viscous resistance of the liquid because particles migrate in the liquid. In addition, since particles of high specific gravity such as titanium oxide are dispersed in a solution of low specific gravity, sedimentation is likely to occur, and the stability of the dispersed state is difficult to maintain. Have In addition, even in the case of a micro cub, the cell size is set to the microcapsule level, and the above-mentioned drawbacks appear in the visual sense. , Na,.

[0005] On the other hand, in contrast to the electrophoresis method using behavior in a solution, a conductive particle is used without using a solution. A method of incorporating a carrier and a charge transport layer into a part of a substrate has begun to be proposed (for example, Guo Lao Zhao and three others, "New Toner Display Device (1)", July 21, 1999, Japan Image Annual conference (83 times in total), "Japan Hardcopy '99", pp.249-252. However, the arrangement of the charge transport layer and the charge generation layer complicates the structure, and it is difficult to inject charges uniformly into the conductive particles, which causes a problem of lack of stability.

[0006] As one method for solving the various problems described above, a display medium (a group of particles! Is powdered fluid) is sealed between a front substrate having a front electrode and a rear substrate having a back electrode, 2. Description of the Related Art There has been known an information display device including an information display panel that applies an electric field to a display medium and moves the display medium by Coulomb force or the like to display information such as an image.

[0007] (Problem of the first invention)

An information display device that uses the display medium described above! One end of a row electrode is provided for a row electrode composed of a plurality of electrodes extending in a row direction on one substrate side and a column electrode composed of a plurality of electrode cables extending in a column direction on the other substrate side. When displaying information such as an image on one screen by scanning and applying a voltage to the other end of the force, crosstalk occurs when driving to display in a matrix or when driving segments dynamically. I have a problem.

[0008] Crosstalk (crosstalk) originally refers to a phenomenon in which signals from other lines are mixed in a telephone. In this case, crosstalk refers to the effect of other rows even though a column electrode is not selected. This is a phenomenon in which an image different from the actual one is displayed. In the display by the passive matrix driving of the information display device using the display medium described above, a voltage for maintaining the display is applied to the non-selected rows of the column electrodes. The effect of applying the holding voltage by the number of rows of the column electrodes lowers the contrast and, depending on the display pattern, causes shading to occur in the image display, resulting in unevenness.

(Problem of second invention)

An information display device that uses the display medium described above! One end of a row electrode is provided for a row electrode composed of a plurality of electrodes extending in a row direction on one substrate side and a column electrode composed of a plurality of electrode cables extending in a column direction on the other substrate side. Scan to the other end and apply voltage Therefore, when displaying information such as an image on a single screen, there is a problem that crosstalk occurs when driving in a matrix display or when driving segments dynamically.

[0010] Crosstalk (crosstalk) is a phenomenon in which signals from other lines are mixed together in a telephone. Crosstalk in this case refers to the effect of other rows even though the column electrode is not selected. This is a phenomenon in which an image different from the actual one is displayed. In the display by passive matrix driving of the information display device using the above-described display medium, a voltage for maintaining the display is applied to the non-selected rows of the column electrodes. The effect of applying this holding voltage by the number of rows of the column electrodes causes shading in the image display and causes unevenness.

FIG. 25 is a diagram for describing shading unevenness due to crosstalk in a conventional information display device. In the example shown in FIG. 25, for simplicity, an 8 × 6 image is also formed in which the lower row electrodes 51-1 to 51-6 and the upper column electrodes 52-1 to 52-8 also have a force. Then, a white and black display medium having different charging characteristics are filled between the row electrode and the column electrode, and the row electrode 51-1 to 51-6 and the column electrode 52-1 to 52-8 are filled. Black and white display is performed according to the voltage applied between them. The driving method is a line erasing method in which erasing and writing are repeated for each row, and image display is performed by scanning the row electrodes 51-1 to 51-6 in that order. During scanning, the selected row of row electrodes 51-1 to 51-6 is erased by applying a voltage of 100 to apply a voltage of 0, and non-selected rows are erased by applying a voltage of 0 to erase. This is done by applying a voltage of 50. At the same time, the column electrodes 52-1 to 52-8 apply the voltage 0 at the time of erasing, apply the voltage 100 to the writing column at the time of writing, and apply the voltage 0 to columns other than the writing column.

The example shown in FIG. 25 shows an example in which scanning is started from the row electrode 51-1 and writing is completed in the last row electrode 51-6. In FIG. 25, of the row electrode 51-1 in the first row and the row electrode 52-2 in the second row, a portion which should be white display is displayed in whitish gray due to partial force crosstalk and a portion which should be black display. Is displayed in blackish gray due to crosstalk, and the image display has shading and unevenness.

(Problem of the Third Invention)

In the information display device using the above-described display medium, when driving by simple matrix driving or dynamic driving (segment panel), the cross-section applied to the non-rewritable pixels is controlled. Contrast reduction due to the talk voltage is a problem.

[0014] Crosstalk (crosstalk) originally refers to a phenomenon in which signals from other lines are mixed in a telephone. In this case, crosstalk refers to the effect of other rows even though a column electrode is not selected. This is a phenomenon in which an image different from the actual one is displayed. In the display by the passive matrix driving of the information display device using the display medium described above, a voltage for maintaining the display is applied to the non-selected rows of the column electrodes. The effect of applying the holding voltage by the number of rows of the column electrodes causes shading in the information display and causes unevenness.

Disclosure of the invention

[0015] (First invention)

An object of the first invention of the present invention is to solve the above-mentioned problem and to provide a method of driving an information display device capable of eliminating shading unevenness caused by crosstalk.

[0016] The method for driving an information display device according to the first invention of the present invention is characterized in that at least one of the two substrates having at least one of them is transparent and has at least two types of display having a first color and a second color. A method for driving an information display device in which a medium is sealed and an electric field is applied to a display medium from electrodes provided on each substrate to move the display medium and display information such as an image is provided. A row electrode consisting of a plurality of electrodes extending in the row direction and a column electrode consisting of a plurality of electrodes extending in the column direction on the other substrate side are scanned from one end of the row electrode to the other end. When displaying information such as an image on one screen by applying a voltage, the voltage causing crosstalk in the first color and the crosstalk in the second color occur after the display of one screen is completed. Characterized in that the voltage to be applied is applied at least once to all the cells of the display unit. A.

[0017] As a preferred example of the method of driving the information display device according to the first invention of the present invention, the simplest method for realizing the above is to add two or more lines at the end of a scan, and after one scan is completed, The drive for displaying the first color display and the second color display at least once each is performed, and the image erasing method prior to the image display is such that the image is erased line by line and then the image is written line by line. This may be a line erasing method, or a total erasing method in which images are erased all at once and then an image is written for each line.

[0018] According to the method for driving the information display device according to the first aspect of the present invention, the display of one screen is completed. After that, a voltage for generating crosstalk in the first color and a voltage for generating crosstalk in the second color are applied to all the cells of the display unit at least once each, preferably at the end of the scan. By adding two or more lines, and after one scan, displaying the first color and the second color one or more times each, for example, in the case of black and white display, white is slightly black and pale gray In addition, black can be displayed in a slightly white and dark gray, and unevenness in shading caused by crosstalk can be eliminated when displaying information.

[0019] (Second invention)

An object of the second invention of the present invention is to solve the above-mentioned problems and to provide a method of driving an information display device capable of eliminating contrast reduction and shading unevenness due to crosstalk. is there.

[0020] The method for driving an information display device according to the second invention of the present invention is characterized in that at least one of the two substrates, at least one of which is transparent, has at least two types of display of a first color and a second color. In a method of driving an information display device that encloses a medium, applies an electric field to the display medium from the electrodes, and moves the display medium to display information such as an image, the electric field is applied to the electrodes to generate the electric field. It is characterized in that a pulse-like voltage composed of a plurality of voltages including a drive voltage in an on state and a voltage equal to or lower than a threshold value at which a display medium in an off state starts moving is applied as a drive voltage. . Here, the driving voltage V is larger than the threshold voltage V (V> V> V: V is

1 100 voltage below threshold).

[0021] As a preferred example of the driving method of the information display device according to the second invention of the present invention, the duty ratio of the pulse-like voltage (= pulse width Z (pulse width + time in off state)) is 0.9 or less. And that the off-state time is 0.1 msec or more.

According to the method of driving the information display device according to the second aspect of the present invention, the drive voltage applied to the electrodes to generate an electric field includes a drive voltage in an on state and a display medium in an off state. By applying a pulse-like voltage composed of a plurality of voltages with a voltage equal to or lower than the threshold value for starting the contrast, it is possible to eliminate the decrease in contrast and the unevenness in density due to crosstalk.

(Third invention)

An object of the third invention of the present invention is to solve the above-mentioned problems and to reduce the problem caused by the crosstalk voltage. It is an object of the present invention to provide a method for driving an information display device, which can eliminate a decrease in contrast.

[0024] In the method for driving an information display device according to a third aspect of the present invention, a display medium is sealed between two opposing substrates, at least one of which is transparent, and an electric field is applied to the display medium from the electrodes. In a method of driving an information display device that displays information such as an image by moving a display medium, a pulse is applied a plurality of times during one pixel rewrite, and a pulse is applied to a non-rewritten pixel during one pixel rewrite. The drive waveform is adjusted so that the polarity of the crosstalk voltage does not change.

[0025] A preferred example of the driving method of the information display device according to the third invention of the present invention is that a pulse in a pulse voltage applied to a pixel to be rewritten while a plurality of pulses are applied in one pixel rewriting. Widening the interval between the peaks, and configuring the row (scan) drive voltage and column drive voltage with pulse trains of the same cycle and the same duty, respectively, when selecting the row side, select the row drive voltage and column drive voltage. Invert the phase of each pulse train.

[0026] According to the driving method of the information display device according to the third aspect of the present invention, a pulse is applied a plurality of times in one pixel rewriting, and is applied to a non-rewritten pixel during one pixel rewriting. By adjusting the drive waveform so that the polarity of the crosstalk voltage does not change, it is possible to eliminate a decrease in contrast due to the crosstalk voltage.

Brief Description of Drawings

[FIG. 1] (a) and (b) are diagrams each showing an example of an information display panel provided in the information display device of the present invention.

2] (a) and (b) are diagrams each showing another example of the information display panel provided in the information display device of the present invention. [FIG.

FIGS. 3 (a) and 3 (b) are diagrams showing still another example of the information display panel provided in the information display device of the present invention.

[FIG. 4] (a) and (b) show the driving method of the information display device according to the first invention of the present invention, respectively.

FIG. 16 is a diagram for explaining an example added to the conventional example shown in FIG.

FIGS. 5 (a) and 5 (b) show the driving method of the information display device according to the first invention of the present invention, respectively. FIG. 16 is a diagram for explaining another example added to the conventional example shown in FIG.

圆 6] (a) and (b) are diagrams for explaining another example of the method of driving the information display device according to the first invention of the present invention.

[7] FIG. 7 is a diagram for explaining the effect of the driving method of the information display device according to the first invention of the present invention.

圆 8] (a) and (b) are diagrams for explaining the effect of the method for driving the information display device according to the first invention of the present invention.

[9] (a) and (b) are diagrams illustrating the effect of the driving method of the information display device according to the first invention of the present invention.

[10] FIG. 10 is a diagram showing an example of a pulse voltage used in the method for driving the information display device according to the second invention of the present invention.

[FIG. 11] (a) and (b) are diagrams showing states when row 1 and row 2 are selected in a simple matrix of 2 rows and 2 columns, respectively (third invention).

[12] FIG. 12 is a view showing an example of a shape of a partition wall in the information display device of the present invention.

FIG. 13 is a diagram showing an example of a test pattern displayed by passive matrix driving (second invention).

[14] FIG. 14 is a diagram showing a display screen and a measurement area when a test pattern is actually displayed (second invention).

[15] FIG. 15 is a graph showing the relationship between the applied voltage and the reflectance measured in each region shown in FIG. 14 (second invention).

FIG. 16 is a graph showing a relationship between a duty ratio and a contrast in a noisy drive voltage (second invention).

FIG. 17 is a graph showing a relationship between a duty ratio and a margin in a noisy drive voltage (second invention).

FIG. 18 is a graph showing the relationship between the off-time and the margin at a noisy drive voltage (second invention).

FIG. 19 is a view for explaining an example of a simple matrix panel composed of row electrodes and column electrodes (third invention). FIG. 20 is a diagram for explaining the driving method of Comparative Example 1 (third invention).

FIG. 21 is a diagram for explaining a driving method according to the first embodiment (third invention).

FIG. 22 is a diagram for explaining a driving method according to the second embodiment (third invention).

FIG. 23 is a view for explaining the driving method according to the third embodiment (third invention).

[FIG. 24] (a) and (b) are diagrams for explaining a test pattern and a measurement position on the test pattern, respectively (third invention).

FIG. 25 is a diagram for explaining shading in a conventional information display device due to crosstalk.

BEST MODE FOR CARRYING OUT THE INVENTION

First, the basic configuration of the information display panel provided in the information display device of the present invention using a particle group will be described. In the information display panel used in the present invention, an electric field is applied to a particle group sealed between two opposing substrates. Along the direction of the applied electric field, low-charged particles are attracted to the high potential side by Coulomb force, and high-charged particles are attracted to the low potential side. The particles are attracted by the Coulomb force or the like, and the direction of movement is switched by the change in the direction of the electric field due to the switching of the potential, whereby information is displayed. Therefore, it is necessary to design an information display panel so that the particles can move uniformly and maintain stability when display rewriting is repeatedly performed or when continuous display, that is, when the display is kept as it is. There is. Here, the force applied to the particles may be, for example, a force attracting each other due to the Coulomb force between the particles, an electric image force with an electrode or a substrate, an intermolecular force, a liquid crosslinking force, gravity, and the like.

An example of an information display panel to which the present invention is applied will be described based on FIGS. 1 (a) and 1 (b) to 3 (a) and 3 (b).

In the examples shown in FIGS. 1 (a) and 1 (b), at least two or more types of display media 3 (here, particles) having different optical reflectivity and charging characteristics are also configured, each having at least one type of particle force. A white display medium 3W composed of a group of particles and a black display medium 3B composed of a group of particles are shown), and the substrates 1 and 2 are arranged in accordance with the electric field generated from electrodes (not shown) arranged outside the substrates 1 and 2. The display is moved perpendicular to 2, and the black display medium 3B is visually recognized by the observer to perform black display, or the white display medium 3W is visually recognized by the observer to perform white display. Fig. 1 (b) In the example shown in FIG. 1A, in addition to the example shown in FIG. Further, in FIG. 1 (b), a partition wall in the foreground is omitted.

In the examples shown in FIGS. 2 (a) and 2 (b), at least two or more types of display media 3 (here, particles having different optical reflectivities and charging characteristics) each comprising at least one type of particle force are also shown. Electric field generated by applying a voltage between the electrode 5 provided on the substrate 1 and the electrode 6 provided on the substrate 2). Is moved vertically with respect to the substrate 2, and the black display medium 3B is visually recognized by the observer to perform black display, or the white display medium 3W is visually recognized by the observer to perform white display. . In the example shown in FIG. 2 (b), in addition to the example shown in FIG. 2 (a), for example, a partition 4 is provided between the substrates 1 and 2 in a lattice shape to form a cell. Also, in FIG. 2 (b), the partition wall in front is omitted.

In the example shown in FIGS. 3 (a) and 3 (b), one type of display medium 3 having optical reflectivity and chargeability (at this time, a particle group force of white Display medium 3W) is moved in a direction parallel to the substrate 2 in accordance with an electric field generated by applying a voltage between the electrodes 5 and 6 provided on the substrate 1, and the white display medium 3W is moved. Either the white color is displayed by the observer or the color of the electrode 6 or the substrate 1 is displayed by making the observer visually recognize the color of the electrode 6 or the substrate 1. In the example shown in FIG. 3 (b), in addition to the example shown in FIG. 3 (a), for example, a grid-like partition 4 is provided between the substrate 2 and the substrate 2 to form a cell. Also, in FIG. 3 (b), the partition in the foreground is omitted.

[0033] The above description also applies to the case where the white display medium 3W composed of particle groups is replaced with a white display medium composed of powdered fluid, and the black display medium 3B also composed of particle groups is replaced by a black display medium also composed of powdered fluid. Can be applied to

(Description of First Invention)

The features of the driving method of the information display device according to the first invention of the present invention include a row electrode composed of a plurality of electrodes extending in the row direction on one substrate side and a plurality of row electrodes extending in the column direction on the other substrate side. In order to display information such as an image on one screen by scanning the one end of the row electrode and applying the voltage to the other end of the row electrode, the display of one screen ends. After that, the voltage that causes crosstalk in the first color = crosstalk voltage 1 and the voltage that causes crosstalk in the second color = crosstalk voltage 2 are applied to all cells in the display at least once. At the point of application. Here, the crosstalk voltages 1 and 2 refer to a voltage of 100 and a voltage of −100 in order to display white as the first color and black as the second color. And a voltage of 50 is applied as the crosstalk voltage 2. Specifically, two or more lines are added at the end of the scan, and after one scan is completed, the display of the first color and the display of the second color may be displayed one or more times.

FIGS. 4 (a) and 4 (b) and FIGS. 5 (a) and 5 (b) are diagrams for explaining examples in which the driving method of the present invention is added to the conventional example shown in FIG. . In the examples shown in FIGS. 4 (a) and 4 (b) and FIGS. 5 (a) and 5 (b), like the conventional example shown in FIG. 25, the row electrodes 111 to 116 and the column electrodes 12-1 to 12- In addition to the provision of 8, row electrodes 11-7 and 11-8 are previously provided as the last two rows.

In the example shown in FIGS. 4 (a) and 4 (b), after scanning of the image display portion is completed, here, scanning is performed up to the row electrodes 11-6 to form an image of one screen of 8 × 6 pixels. After displaying such information as shown in FIG. 4 (a), the row electrodes 11-7, which is the first of the last two rows, are erased as shown in FIG. Perform white writing. Next, after erasing the electrode 118 as the second row of the last two rows as shown in FIG. 5A, black writing is performed as shown in FIG. 5B. As a result, as shown in Fig. 5 (b), the white color is unified to light gray, the black color is unified to dark gray, and they are not 100% white or black, respectively. Since the portions displayed in light and gray and those displayed in black are all displayed in dark and gray, unevenness in light and shade caused by crosstalk can be completely eliminated.

In the examples shown in FIGS. 4 (a) and 4 (b) and FIGS. 5 (a) and 5 (b), the line erasing method in which the force erased for each line is also described as an example. Even with the total erasure method of writing every power line, unevenness of light and shade can be eliminated similarly. In addition, although an example of white erasing at the time of erasing is shown, unevenness of shading can be similarly eliminated in black erasing. In addition, in the examples shown in FIGS. 4 (a), (b), and FIGS. 5 (a), (b), the row electrodes 117, 118 were added and the display medium was filled to actually display black and white. However, even if no electrode is provided, two or more rows to be driven are added Also, by applying a voltage for displaying white and a voltage for displaying black to the added row, the unevenness of density can be similarly eliminated.

[0038] As described above, in the method for driving the information display device according to the first invention of the present invention, it is assumed that a crosstalk occurs, and that the grayscale pixel due to the generated crosstalk is used. Eliminate shading by combining the first color (for example, white) or the second color (for example, black) with the color to make the first color light gray or the second color to dark gray The point has the biggest feature.

FIGS. 6A and 6B are diagrams for explaining another example of the method of driving the information display device according to the first invention of the present invention. As shown in Fig. 6 (a) or (b), the checker pattern is displayed on the last two rows, row electrodes 117, 11-8, to show Figs. 4 (a), (b) and 5 As in the examples shown in (a) and (b), unevenness of shading is eliminated. Here, by displaying the checker pattern, when displaying the first color and the second color for each column in the last two rows, the first two rows are displayed for each column in the last two rows. In displaying the color and the second color, the display of the first color and the display of the second color in each column are performed in a zigzag manner different from each other, or a newly provided row electrode is provided. When a voltage for displaying the first color and a voltage for displaying the second color are applied between the column and the extended portion of each column electrode, the display of the first color and the second color is performed in each column. It is possible to achieve the application of the voltage so as to perform the zigzag display in which the display order is different from each other.

Next, an example in which the driving method of the information display device according to the first invention of the present invention is actually applied will be described. FIGS. 7, 8 (a), (b), 9 (a), and (b) are diagrams for explaining the effects of the driving method of the information display device of the present invention. First, in this example, the pattern image shown in FIG. 7 is displayed. Fig. 8 (a) shows an example of displaying a pattern image using the conventional driving method in line erasing. Figure 8 (b) shows an example of the image displayed. Fig. 9 (a) shows an example of a pattern image displayed by the conventional driving method in all erasure. Figure 9 (b) shows an example in which is displayed. Comparing Fig. 8 (a) and Fig. 8 (b), and Fig. 9 (a) and Fig. 9 (b), both the line erase method and the all erase method It can be seen that the shading caused by the crosstalk is remarkable, whereas the shading unevenness caused by the crosstalk is not present in the example of the present invention.

In the above-described example, the voltage 100 applied when erasing or writing a pixel is touched, but the density of an image greatly differs depending on the value of the voltage V depending on the structure of the information display device. In general, when the voltage V is low, black display cannot be performed, while when the voltage 100 is high, the difference between the gray portion and the black portion due to the crosstalk disappears. Therefore, it is necessary to select the optimal voltage according to the structure of the information display device. For example, a voltage of about 80V to 110V is used.

(Description of Second Invention)

The feature of the method for driving the information display device according to the second invention of the present invention is that, unlike the information display device having the above-described configuration, the drive voltage V, which is conventionally in the ON state for displaying an image, is continuously applied. However, on the other hand, the driving voltage V in the ON state and the voltage V pulse below the threshold value at which the display medium in the OFF state starts moving.

The point is to apply a voltage that reciprocates between zero. In other words, the OFF state time (=

0

Using a new concept of off-time, the cross-talk is reduced by controlling the off-time. At this time, V and V can take a plurality of values and may be gradually changed.

0

FIG. 10 is a diagram showing an example of a pulse voltage used in the method for driving the information display device according to the second invention of the present invention. In the example shown in FIG. 10, the pulse voltage used in the present invention is such that the drive voltage in the on state and the display medium in the off state start to move! As shown. As a preferred example of the present invention, the duty ratio of the pulse voltage (= pulse width Z (pulse width + time in off state)) is 0.9 or less, and the off state time is 0.1 msec or more. There is that. Both examples will be described in detail in embodiments described later.

(Description of Third Invention)

The feature of the driving method of the information display device according to the third invention of the present invention is that the information display device having the above-described configuration has a crosstalk voltage waveform when various driving methods are applied in more detail, and is optimized. The point is that the contrast is improved by selecting an appropriate method. Specifically, while applying a pulse multiple times during one pixel rewrite, the non-rewrite pixel The polarity of the crosstalk voltage applied to the non-rewriting pixel does not change, that is, the pulse of the crosstalk voltage given as the difference between the row (scanning) drive voltage and the column drive voltage in the non-rewrite pixel has a positive and negative polarity The point is that the drive voltage pulse waveform is adjusted so that it does not exist over the region, in other words, it exists only in the positive region when it is positive, and it exists only in the negative region when it is negative.

FIGS. 11 (a) and 11 (b) are diagrams showing states when row 1 and row 2 are selected in a simple matrix of 2 rows and 2 columns, respectively. In the examples shown in FIGS. 11 (a) and 11 (b), when a rewrite voltage is applied to a pixel to be rewritten (the hatched portion in the figure), three types of crosstalk voltages 1 to 3 are applied. Even if the number of matrices increases, only the above two types of voltages exist (two types: selected for row, two types for non-selection, rewrite for column, two types for non-rewrite, two types of 2 × 2. If various drive logics are used, more types of voltages exist.) If the crosstalk voltage is not 0 V, the non-rewritable pixel becomes black (gray) with more whiteness if it is black, for example, and becomes white (gray) with more blackness if it is white (for black and white display). ). In the case of an information display device with image memory, it is necessary to perform writing (in some cases, concurrence with erasing) by inverting the polarity of the applied voltage.

Further, as a preferred example of the method of driving the information display device according to the third invention of the present invention, in addition to the above-described improvement of the contrast, the rewriting pixel is applied while applying the pulse a plurality of times in one pixel rewriting. By increasing the interval between the peaks in the pulse voltage applied to the pixel, the display color of the rewritten pixel can be increased, and as a result, the contrast can be further improved. Specifically, the row (scanning) drive voltage and the column drive voltage are composed of pulse trains having the same cycle and the same duty, respectively, and when selecting a row on the row side, each of the port drive voltage and the column drive voltage is used. By inverting the phase of the pulse train, the crosstalk voltage given as the difference between the row (scanning) drive voltage and the column drive voltage at the rewrite pixel increases the difference between the peak 'toe' peaks, thereby increasing the color of the rewrite pixel. Can be increased. Both examples will be described in detail in embodiments described later.

Hereinafter, each member constituting the information display panel to which the present invention is applied will be described.

[0048] As for the substrate, at least one of the substrates is a force outside the information display panel. It is a transparent front substrate 2 whose color can be confirmed, and a material having high visible light transmittance and good heat resistance is preferable. The rear substrate 1 may be transparent or opaque. Examples of the substrate material include polymer sheets such as polyethylene terephthalate, polyether sulfone, polyethylene, polycarbonate, polyimide, and acrylic, and flexible materials such as metal sheets, and flexible materials such as glass and quartz. Inorganic sheet having no properties. The thickness of the substrate is preferably between 2 and 5000 μm, and more preferably between 5 and 2000 μm.If the thickness is too small, the strength and uniformity between the substrates are maintained.If the thickness is more than 5000 / zm, This is inconvenient when using a thin information display panel.

[0049] When forming electrodes on the information display panel, examples of the electrode forming material include metals such as aluminum, silver, nickel, copper, and gold, _ITO , indium oxide, conductive tin oxide, and conductive zinc oxide. Examples of such conductive metal oxides and conductive polymers such as polyaline, polypyrrole, and polythiophene are exemplified and appropriately selected for use. Examples of the method of forming the electrode include a method of forming the above-described materials into a thin film by a sputtering method, a vacuum evaporation method, a CVD (chemical vapor deposition) method, a coating method, or a method in which a conductive agent is mixed with a solvent or a synthetic resin binder. A method of applying is used. The electrode provided on the viewing side (display surface side) substrate needs to be transparent. The electrode provided on the back side substrate does not need to be transparent. In any case, the above-mentioned conductive material capable of forming a pattern can be suitably used. The thickness of the electrode is preferably 3 to: LOOO nm, and more preferably 5 to 400 nm, as long as the conductivity can be ensured and the light transmittance is not impaired. The material and thickness of the electrodes provided on the back side substrate are the same as those of the electrodes provided on the display surface side substrate, and need not be transparent. In this case, the external voltage input may be superimposed with DC or AC.

[0050] The shape of the partition wall 4 provided as necessary is appropriately set appropriately according to the type of the display medium involved in the display, and is not particularly limited, but the width of the partition wall is 2 to: ίΟΟ / ζπι, preferably Preferably, the height is adjusted to 3 to 50 μm, and the height of the septum is adjusted to 10 to 500 μm, preferably 10 to 200 μm. Further, in forming the partition, a two-rib method in which ribs are formed on both of the opposing substrates and then joined, or a one-rib method in which the ribs are formed only on one substrate is conceivable. In the present invention, any of the methods is suitably used.

The cells formed by the ribs having the rib force are arranged on the substrate plane as shown in FIG. Seen from the direction, a square shape, a triangular shape, a line shape, a circular shape, and a hexagonal shape are exemplified, and the arrangement is exemplified by a lattice shape, a honeycomb shape, and a mesh shape. It is better to make the part (area of the cell frame) corresponding to the cross-section of the partition seen from the display surface side as small as possible, and the sharpness of the display state increases. Here, examples of the method for forming the partition include a mold transfer method, a screen printing method, a sand blast method, a photolithography method, and an additive method. Of these, a photolithography method using a resist film and a mold transfer method are preferably used.

Next, the particle group used as a display medium in the information display panel according to the present invention will be described. The particles constituting the particle group can contain a charge control agent, a coloring agent, an inorganic additive, and the like, as necessary, in a resin as a main component thereof, as necessary. The following are examples of resins, charge control agents, coloring agents, and other additives.

Examples of the resin include urethane resin, urethane resin, acrylic resin, polyester resin, acrylic urethane resin, acrylic urethane silicone resin, acrylic urethane fluorine resin, acrylic fluorine resin, Silicone resin, acrylic silicone resin, epoxy resin, polystyrene resin, styrene acrylic resin, polyolefin resin, butyral resin, vinylidene chloride resin, melamine resin, phenol resin, fluorine resin, polycarbonate. Fat, polysulfone resin, polyether resin, polyamide resin, and the like, and two or more kinds can be mixed. In particular, from the viewpoint of controlling the adhesion to the substrate, acrylic urethane resin, acrylic silicone resin, acrylic fluorine resin, acrylic urethane silicone resin, acrylic urethane fluorine resin, fluorine resin, silicone resin. Is preferred.

The charge control agent is not particularly limited, but examples of the charge control agent include a metal salicylate complex, a metal-containing azo dye, and a metal-containing dye (including a metal ion and a metal atom) in an oil-soluble dye. Materials, quaternary ammonium salt-based compounds, Rick's Allylene conjugates, boron-containing compounds (boron benzylate complexes), nitroimidazole derivatives and the like. Examples of the positive charge control agent include a nig mouth dye, a triphenylmethane compound, a quaternary ammonium salt compound, a polyamine resin, and an imidazole derivative. In addition, metal oxides such as ultrafine silica, ultrafine titanium oxide and ultrafine alumina, nitrogen-containing cyclic compounds such as pyridine and derivatives and salts thereof, various organic pigments, and resins containing fluorine, chlorine, nitrogen, etc. Can also be used as a charge control agent. [0055] As the colorant, various kinds of organic or inorganic pigments and dyes as exemplified below can be used.

[0056] Examples of the black colorant include carbon black, copper oxide, dimanganese diacid, arin black, activated carbon and the like.

Blue colorants include CI Pigment Blue 15: 3, CI Pigment Blue 15, Navy Blue, Cobalt Blue, Alkaline Blue Lake, Victoria Blue Lake, Phthalocyanine Blue, Metal-Free Phthalocyanine Blue, Partially Chlorinated Phthalocyanine Blue, First Sky Blue and Indanthrene Blue BC are available.

Red colorants include Bengala, Cadmium Red, Lead Tan, Mercury Sulfide, Cadmium, Permanent Red 4R, Linole Red, Pyrazolone Red, Watching Red, Calcium Salt, Lake Red D, Brilliant Carmine 6B, Eosin Lake, Rhodamine Lake B, Aliza Lin Lake, Brilliant Carmine 3B, CI Pigment Red 2, etc.

[0057] Examples of the yellow colorant include graphite, zinc yellow, cadmium yellow, yellow iron oxide, mineral yellow, nickel yellow, yellow yellow, navy yellow, naphtho no yellow yellow S, nonzai yellow G, hanzi yellow 10G, benzidine Yellow G, Benzijin Yellow GR, Quinoline Yellow Lake, Permanent Yellow NCG, Tartrazine Lake, CI Pigment Yellow 12 and others.

Examples of the green colorant include chrome green, oxidized chromium, pigment green B, CI pigment green 7, malachite green lake, and huainanorayello green G. Orange colorants include red lead, molybdenum orange, permanent orange GTR, pyrazolone age range, norecan age range, indanthrene brilliant age range RK :, benzidine age range G, indanthrene brilliant age range GK, CI Pigment Age Range 3 1 mag.

Purple colorants include manganese violet, first violet B, methyl violet lake, and the like.

Examples of white colorants include zinc white, titanium oxide, antimony white, zinc sulfate, and the like.

[0058] Examples of extenders include norite powder, barium carbonate, clay, silica, white carbon, talc, and alumina white. Also, with various dyes such as basic, acidic, dispersion, direct dye And Nigguchi Shin, Methylene Blue, Rose Bengal, Quinoline Yellow, Ultramarine Blue and the like.

[0059] Examples of the inorganic additives include titanium oxide, zinc white, zinc sulfide, antimony oxide, calcium carbonate, lead white, talc, silica, calcium silicate, alumina white, cadmium yellow, cadmium red, and cadmium. Orange, titanium yellow, navy blue, ultramarine, cobalt blue, cobalt green, cobalt violet, iron oxide, carbon black, manganese ferrite black, cobalt ferrite black, copper powder, aluminum powder and the like. These pigments and inorganic additives can be used alone or in combination. Of these, carbon black is particularly preferred as the black pigment, and titanium oxide is preferred as the white pigment.

The particles used in the present invention have an average particle diameter d (0.5) force of 0.1 to 20 μm, and are preferably uniform and uniform. If the average particle diameter d (0.5) is larger than this range, the sharpness of the display will be poor, and if it is smaller than this range, the cohesion between the particles will be too large and the movement of the particles will be hindered.

[0061] Further, in the present invention, regarding the particle size distribution of each particle, the particle size distribution Span represented by the following formula is set to less than 5, preferably less than 3.

Span = (d (0.9) -d (0.1)) /d(0.5)

(However, d (0.5) is the numerical value of the particle diameter in which 50% of the particles are larger and 50% is smaller than this, expressed in m, and d (0.1) is the particle in which the ratio of particles smaller than 10% is 10%.) The particle diameter is expressed as / zm, and d (0.9) is the particle diameter at which 90% of the particles are 90% or less./zm.) By setting the Span within the range of 5 or less, The size is uniform and uniform particle movement is possible.

[0062] Furthermore, regarding the correlation of each particle, of the particles used, the ratio of d (0.5) of the particle having the minimum diameter to d (0.5) of the particle having the maximum diameter is 50 or less, preferably 10 or less. It is important to do so. Even if the particle size distribution Span is reduced, particles with different charging characteristics move in opposite directions, so that particles with similar particle sizes can easily move in opposite directions by an equivalent amount. It is preferable that the force falls within this range. [0063] The above-mentioned particle size distribution and particle size can be determined by a laser diffraction Z scattering method or the like. When laser light is applied to the particles to be measured, a spatial light intensity distribution pattern of the diffracted Z scattered light is generated, and since this light intensity pattern has a correspondence with the particle size, the particle size and the particle size distribution are measured. it can.

Here, the particle size and the particle size distribution in the present invention are obtained from a volume-based distribution. Specifically, using a Mastersizer2000 (Malvern Instruments Ltd.) measuring instrument, the particles are put into a nitrogen gas stream, and the particles are analyzed using the attached analysis software (software based on volume-based distribution using Mie theory). Measurements of diameter and particle size distribution can be made.

Although the charge amount of the particles naturally depends on the measurement conditions, the charge amount of the particles in the information display panel is almost the same as the initial charge amount, the contact with the partition, the contact with the substrate, and the charge accompanying the elapsed time. It was found that it depends on the attenuation, and in particular, the saturation value of the charging behavior of the particles is the dominant factor.

As a result of intensive studies, the present inventors have found that by measuring the charge amount of each particle using the same carrier particles in the blow-off method, it is possible to evaluate the appropriate range of the charge characteristic value of the particles used. I found it.

Next, a powder fluid used as a display medium in the information display panel according to the present invention will be described. The name of the liquid powder used in the information display device of the present invention is obtained by the present applicant with the right of “Electronic powder liquid (registered trademark): registration number 4636931”.

[0067] The "powder fluid" in the present invention is a substance in an intermediate state between a fluid and a particle that exhibits fluidity by itself without using the power of gas or liquid. For example, a liquid crystal is defined as an intermediate phase between a liquid and a solid, and has fluidity, a characteristic of liquid, and anisotropy (optical properties), a characteristic of solid (Heibonsha: Encyclopedia) ). On the other hand, the definition of a particle is an object having a finite mass, even if it is negligible, and is said to be affected by gravity (Maruzen: Encyclopedia of Physics). Here, particles also have a special state of gas-solid fluidized bed or liquid-solid fluid. When gas flows from the bottom plate to the particles, an upward force acts on the particles corresponding to the velocity of the gas. When the fluid balances with gravity, it is called a gas-solid fluidized bed that can easily flow like a fluid, and the fluidized fluidized state is called a liquid-solid fluidized body. (Heibonsha: Encyclopedia). Gas-solid fluidized bed And liquid-solid fluids are in a state utilizing the flow of gas or liquid. In the present invention, it has been found that a substance in a state of fluidity can be specifically produced without using the power of such a gas or the power of a liquid, and this is defined as a powder fluid.

That is, as in the definition of the liquid crystal (intermediate phase between liquid and solid), the powder fluid in the present invention is an intermediate state having both characteristics of particles and liquid, and has the characteristics of the particles described above. A substance that exhibits a unique state of high fluidity that is extremely insensitive to gravity. Such a substance can be obtained in an aerosol state, that is, a dispersion system in which a solid or liquid substance is stably suspended as a dispersoid in a gas, and the solid substance is dispersed in the information display panel of the present invention. It is assumed that.

[0069] The information display panel that is the object of the present invention is a powder fluid that exhibits high fluidity in an aerosol state in which solid particles are stably suspended as a dispersoid in a gas between opposed substrates, at least one of which is transparent. Such a powder fluid can be easily and stably moved by a cooler or the like when a low voltage is applied.

The powder fluid used in the present invention is, as described above, a substance in an intermediate state between a fluid and a particle, which exhibits fluidity by itself without using the power of gas or liquid. The powdered fluid can be in an aerosol state, and the information display panel of the present invention is used in a state where a solid substance is relatively stably suspended as a dispersoid in a gas.

[0070] The range of the aerosol state is preferably twice or more the maximum apparent volume of the powder fluid when it was not suspended, more preferably 2.5 times or more, and particularly preferably 3 times or more. You. The upper limit is not particularly limited, but is preferably 12 times or less.

If the apparent volume at the time of the maximum suspension of the powder fluid is smaller than twice that of the non-floating state, it will be difficult to control the display.If the apparent volume is larger than 12 times, the powder fluid will flutter too much when enclosed in the device. Inconvenience in handling occurs. The apparent volume at the time of maximum suspension is measured as follows. That is, the powdered fluid is placed in a closed container through which the powdered fluid can be seen, and the container itself is vibrated or dropped to create a maximum floating state, and the apparent volume at that time is also measured for the external force of the container. Specifically, a powdery liquid with no suspension is placed in a container with a lid made of polypropylene (trade name: i-boy: Azwan Corporation) with an average particle diameter d (0.5) (inner diameter) of 6 cm and a height of 10 cm. Then, put the powder fluid equivalent to the volume of 1Z5, set the container on a shaker, and shake for 3 hours at 3 round trip Zsec over a distance of 6cm. The apparent volume immediately after stopping shaking is the apparent volume at the time of maximum suspension.

Further, in the present invention, it is preferable that the temporal change of the apparent volume of the powder fluid satisfies the following expression.

V / V> 0.8

10 5

Where V is the apparent volume (cm ³ ) 5 minutes after the maximum suspension, and V is 10

5 10

Shows the apparent volume (cm ³ ) after minutes. In the information display device of the present invention, it is preferable that the temporal change V / V of the apparent volume of the powdery fluid is larger than 0.85, and more preferable that it is larger than 0.9.

10 5

Is particularly preferred. If V / V is 0.8 or less, the field using ordinary so-called particles

10 5

In this case, the effects of high-speed response and durability as in the present invention cannot be secured.

[0072] Further, the average particle diameter d (0.5) (d (0.5)) of the particulate matter constituting the powder fluid is preferably 0.1 to 20 111, and more preferably 0.5 to 15 111, particularly preferably 0.9 to 8 m. If it is smaller than 0.1 m, it will be difficult to control the display. If it is larger than 20 m, the display will be less clear. The average particle size d (0.5) (d (0.5)) of the particulate matter constituting the powder fluid is the same as d (0.5) in the next particle size distribution Span.

[0073] The particle material constituting the powder fluid preferably has a particle size distribution Span represented by the following formula of less than 5, more preferably less than 3.

Particle size distribution Span = (d (0.9) —d (0.l)) / d (0.5)

Here, d (0.5) is a numerical value expressed by / zm that 50% of the particulate matter constituting the powder fluid is larger than 50% and smaller than 50%, and d (0.1) is Numerical value in μm of the particle diameter where the ratio of the particulate matter constituting the powder fluid is 10%, and d (0.9) is the particle where the particulate matter constituting the powder fluid is 90% or less. It is a numerical value representing the diameter in / zm. By setting the particle size distribution Span of the particulate matter constituting the powder fluid to 5 or less, the size becomes uniform and the powder fluid can be moved uniformly.

[0074] The above particle size distribution and particle size can be determined by a laser diffraction Z scattering method or the like. When a laser beam is irradiated to the powder fluid to be measured, a spatially diffracted Z-scattered light intensity distribution pattern is generated, and this light intensity pattern has a correspondence with the particle diameter. Thus, the particle size and the particle size distribution can be measured. The particle size and the particle size distribution are obtained from a volume-based distribution. Specifically, using a Mastersizer2000 (Malvern Instruments Ltd.) measuring machine, charge the powder fluid into a nitrogen stream, and use the attached analysis software (software based on volume-based distribution using Mie theory) A measurement can be made.

[0075] Powder fluid is produced by kneading and kneading necessary resins, charge control agents, coloring agents, and other additives, or by polymerizing with monomers, to convert existing particles into resins, charge control agents, It may be coated with a coloring agent or other additives. Hereinafter, the resin, the charge control agent, the coloring agent, and other additives constituting the powder fluid will be exemplified.

[0076] Examples of the resin include urethane resin, acrylic resin, polyester resin, urethane-modified acrylic resin, silicone resin, nylon resin, epoxy resin, styrene resin, and butyral resin. And acrylamine resin, melamine resin, phenol resin, fluorine resin and the like. Two or more of them can be mixed. Particularly, in order to control the adhesion to the substrate, acrylic urethane resin is used. Preferred are acrylic urethane silicone resin, acrylic urethane fluorine resin, urethane resin, and fluorine resin.

[0077] Examples of the charge control agent include, in the case of imparting a positive charge, a quaternary ammonium salt-based compound, a Nigguchi syn dye, a triphenylmethane-based compound, and an imidazole derivative. In such a case, a metal-containing azo dye, a metal salicylate complex, a nitroimidazole derivative and the like can be mentioned.

[0078] As the coloring agent, various kinds of organic or inorganic pigments and dyes as exemplified below can be used.

[0079] Examples of the black colorant include carbon black, copper oxide, dimanganese diacid, arin black, activated carbon and the like.

Red colorants include Bengala, Cadmium Red, Lead Tan, Mercury Sulfide, Cadmium, Permanent Red 4R, Linol Red, Pyrazolone Red, Watching Red, Calcium Salt , Lake Red D, Brilliant Carmine 6B, Eosin Lake, Rhodamine Lake B, Aliza Lin Lake, Brilliant Carmine 3B, CI Pigment Red 2, etc.

[0080] Examples of the yellow colorant include graphite, zinc yellow, cadmium yellow, yellow iron oxide, mineral yellow yellow, nickele titanium yellow, neve yellow, naphthone yellow S, nonza yellow G, hanza yellow 10G, and benzidine. Yellow G, Benzijin Yellow GR, Quinoline Yellow Lake, Permanent Yellow NCG, Tartrazine Lake, CI Pigment Yellow 12 and others.

[0081] Examples of extenders include norite powder, barium carbonate, clay, silica, white carbon, talc, and alumina white. Various dyes such as basic, acidic, disperse and direct dyes include Nigguchi Shin, Methylene Blue, Rose Bengal, Quinoline Yellow and Ultramarine Blue.

Examples of inorganic additives include titanium oxide, zinc white, zinc sulfide, antimony oxide, calcium carbonate, lead white, talc, silica, calcium silicate, alumina white, cadmium yellow, cadmium red, and cadmium. Orange, titanium yellow, navy blue, ultramarine, cobalt blue, cobalt green, cobalt violet, iron oxide, carbon black, manganese ferrite black, cobalt ferrite black, copper powder, aluminum powder and the like. These pigments and inorganic additives can be used alone or in combination. Of these, carbon black is particularly preferred as the black pigment, and titanium oxide is preferred as the white pigment. [0083] Even if such a material is kneaded and coated without any effort while applying force, it is not possible to produce a powder fluid showing an aerosol sol state! It is not clear how the powdered fluid that shows the aerosol state is determined, but for example, it is as follows.

First, it is appropriate to fix inorganic fine particles having an average particle diameter of 20 to: LOOnm, preferably 20 to 80 nm, on the surface of the particle material constituting the powder fluid. Further, it is appropriate that the inorganic fine particles are treated with silicone oil. Here, examples of the inorganic fine particles include silicon dioxide (silica), zinc oxide, aluminum oxide, magnesium oxide, cerium oxide, iron oxide, copper oxide, and the like. The method of fixing the inorganic fine particles is important.For example, using a hybridizer (manufactured by Nara Machinery Co., Ltd.) ゃ mechanofusion (manufactured by Hosokawa Micron Co., Ltd.), etc. ), A powder fluid showing an aerosol state can be produced.

Further, in the present invention, it is important to manage the particles in the substrate or the air in the void surrounding the powder fluid, which contributes to the improvement of display stability. Specifically, it is important that the relative humidity at 25 ° C. of the gas in the void portion be 60% RH or less, preferably 50% RH or less, and more preferably 35% RH or less.

In FIGS. L (a) and (b) to FIGS. 3 (a) and (b), the gap is defined as a portion between the opposing substrates 1 and 2 and the electrodes 5 and 6 (between the electrodes and the inside of the substrate). Excluding the portion occupied by the display medium 3, the portion occupied by the partition 4 (if a partition is provided), and the sealing portion of the information display panel. And

The type of gas in the void portion is not limited as long as it is in the humidity range described above, but dry air, dry nitrogen, dry argon, dry helium, dry carbon dioxide, dry methane and the like are preferable. This gas needs to be sealed in the information display panel so that the humidity is maintained.For example, filling of particles or powder fluid, assembly of the information display panel, etc. under a predetermined humidity environment In addition, it is important to provide a sealing material and a sealing method for preventing external force from entering the humidity.

[0085] The distance between the substrates in the information display panel according to the present invention is not particularly limited as long as the display medium can be moved and the contrast can be maintained, but is usually 10 to 500111, preferably 10 to 200 µm. Adjusted. The volume occupancy of the display medium in the space between the opposing substrates is preferably 5 to 70%, more preferably 5 to 60%. If it exceeds 70%, the movement of the display medium is hindered, and if it is less than 5%, the contrast tends to be unclear.

Example

[0086] Hereinafter, the present invention will be described more specifically with reference to Examples according to the second to third inventions of the present invention. However, the present invention is not limited to the following.

(Example of the Second Invention)

The contrast and drive voltage margins>

The contrast between the contrast and the driving voltage, which is an index for evaluating the driving method of the information display device according to the second invention of the present invention, was defined by performing the following experiment.

[0088] 1. Experimental method

In order to measure the effects of crosstalk, the simplest test pattern was displayed by various driving methods, and the reflectance of the display state when the voltage was changed was measured.

1. 1.Test pattern

Fig. 13 shows a test pattern displayed by noisy matrix driving. In FIG. 13, (a) is a solid black area, (b) is a solid white area, and (c) to (f) are areas affected by crosstalk. Details will be described in the next section.

[0089] 1. 2. Description of typical reflectance applied voltage characteristics

Fig. 14 shows the display screen when the test pattern is displayed, and Fig. 15 shows a typical measured reflectivity-applied voltage characteristic. As shown in Fig. 14, 5 X 5 measurement points were allocated, and the write voltage was gradually applied to the OV force to measure the reflectance at each point when the test pattern was displayed. Of these, the value obtained by averaging the portions surrounded by squares is defined as the reflectance of each region. FIG. 15 shows the characteristic curves of the applied voltage on the horizontal axis and the reflectance on the vertical axis. Hereinafter, each line shown in FIG. 15 will be described. The matrix drive in this experiment was performed as shown in Table 1 below. Further, in the following description, a potential difference is represented by setting a potential applied to a column-side electrode to +. For example, if OV is applied to a column and 50V is applied to a row, the potential difference between the electrodes is 50V. [Table 1]

[0091] (1) Area 21—1

When a line is selected, an O (V) voltage is applied. When a line is not selected, a crosstalk voltage of VZ2 is applied in the first half of scanning—V / 2 in the second half of scanning. In this area, lines are selected in the first half of the scan, but when the applied voltage increases, it is greatly affected by the crosstalk in the second half of the scan, and the display shifts to black despite the white display.

[0092] (2) Area 21-5

When the line is selected, the V voltage is applied. When the line is not selected, the crosstalk voltage of VZ2 is applied in the first half of the scan and VZ2 in the second half. This region, which is selected later in the scan, shows almost the same trend as region 5, since it is hardly affected by crosstalk.

[0093] (3) Area 22—1

When a line is selected, the V voltage is applied. When the line is not selected, a crosstalk voltage of VZ2 is applied in the first half of scanning and one VZ2 in the second half of scanning. In an area where a line is selected in the first half of the scan, the crosstalk in the second half of the scan is greatly affected by an increase in the applied voltage, and the area shifts to white despite black display.

[0094] (4) Region 22—5

When a line is selected, a voltage of 0 (V) is applied. When the line is not selected, a crosstalk voltage of VZ2 is applied in the first half of the scan and —VZ2 in the second half. This region is selected in the second half of the scan, but unlike region 1-5, it is selected by O (V), so the effect of the crosstalk received in the first half remains. For this reason, when the applied voltage becomes higher, the display shifts to a little black despite the white display.

[0095] (5) Area 24

The area where the voltage of O (V) is applied when the line is selected and the voltage of -VZ2 is always applied when the line is not selected remains white display, which is the white reference for each display method. [0096] (6) Area 25

The area where the voltage of V is applied when the line is selected and where the voltage of VZ2 is always applied when the line is not selected remains black display, which is the black reference for each display method.

[0097] 2. Evaluation method

An important evaluation item in displaying a halftone is contrast. The most important area in each area is Area 22-1. No matter how low the minimum reflectance of black is, the contrast is limited to the reflectance in this region because region 22-1 has shifted to white due to crosstalk. Area 21-1 is also strongly affected by crosstalk. This crosstalk change occurs on the higher voltage side compared to area 22-1. Since the purpose is to obtain a good display at lower voltage in order to reduce power consumption, the crosstalk in region 21-1 can be ignored.

Here, the evaluation method in this experiment is defined as follows.

[0098] (1) Contrast (vertical line with double arrow in Fig. 15)

Normal contrast is represented by the ratio of the maximum reflectance of white to the minimum reflectance of black. In this experiment, the following definition was made in consideration of the above items. In other words, contrast was defined as the ratio of the reflectance of the lowest (highest: in the case of blackout white) level of line 22-1 to the reflectance of the white (black: in the case of blackout white) display at that time. Here, “black erase white writing” refers to an “erasing-rewriting method” in which a display state is erased so as to be black, and then a portion desired to be displayed in white is rewritten so as to be white. Conversely, the “erasing-rewriting method” in which the display state is erased so as to be white and then displayed in black and the part is rewritten so as to be black is called “white erase black writing”. The higher the contrast, the better.

[0099] (2) Drive voltage margin (horizontal line with double arrow in Fig. 15)

The drive voltage margin is 10% higher than the difference between the lowest (highest: blacked out white writing) level reflectance of line 22-1 and the white (black: blacked out white writing) display reflectance at that time. (Decreased: black and white) when defined as the width of line 22-1. The drive voltage margin is wider and better.

[0100] <Pulse Drive Voltage>

Using the contrast and drive voltage margin defined as above as indices, The driving voltage was examined. In this experiment, the voltage V was equal to or lower than the threshold value V = o (v).

0

[0101] (1) Duty ratio

First, as the drive voltage, three types of pulse-like voltages, 4 pulses with a pulse width of 0.2 msec, 8 pulses with a pulse width of 0.08 msec, and 8 pulses with a pulse width of 0.2 msec, are used, and the duty of each pulse-like voltage is used. The contrast when various ratios were changed was measured. Figure 16 shows the results. In FIG. 16, the duty ratio on the horizontal axis is shown as a logarithm. From the results shown in FIG. 16, it can be seen that when the duty ratio exceeds 0.9, the contrast is reduced, and that the duty ratio is preferably set to 0.9 or less.

[0102] Next, as the driving voltage, three pulse-like voltages of 4 pulses with a pulse width of 0.2 msec, 8 pulses with a pulse width of 0.08 msec, and 8 pulses with a pulse width of 0.2 msec were used. The margin was measured when the duty ratio of the pulsed voltage was varied. Figure 17 shows the results. From the results of FIG. 17, it can be seen that the smaller the duty ratio is, the larger the margin is, so the smaller the duty ratio is, the more preferable.

[0103] (2) Off time

Based on the data obtained on the relationship between the duty ratio and the contrast or the margin, the relationship between the off-time and the margin was examined. The results are shown in FIG. The results in FIG. 18 show that the margin is reduced when the off-time is less than 0.1 msec, and that the off-time is preferably set to 0.1 msec or more.

(Example of Third Invention)

First, as shown in FIG. 19, a simple matrix panel composed of row electrodes 31-1 to 31-11 and column electrodes 32-1 to 32-111 was manufactured. In a simple matrix panel, one row is selected from row electrodes 31-1 to 31-n, and one screen is rewritten. FIG. 20 shows the driving method of Comparative Example 1, and FIGS. 21 to 23 show the driving methods of Examples 1 to 3. In the driving method of FIGS. 20 to 23, for simplicity of explanation, the same simple matrix panel of 2 rows and 2 columns as that shown in FIGS. 11 (a) and 11 (b) will be described. The following shows an example of driving by applying two pulse voltages (ON-OFF-ON-OFF) during rewriting. Then, the voltage waveforms applied to the rows, columns, and the respective electrodes, and the voltage waveforms applied to each pixel at the time of the first row rewrite (when selected) and the second row rewrite (when selected) are shown. ing. <Comparative Example 1>

In the driving method of Comparative Example 1 shown in FIG. 20, the column rewrite voltage is applied twice in a pulsed manner, while the row selection voltage is the same as the conventional one. In this example, the polarity of the pulse voltage at crosstalk 2 and 4 applied to the non-rewritable pixel changes from + VI to one VI and to one VI from the other. Is large. In both cases, the display medium was more likely to move, and the contrast was more strongly affected by the crosstalk, and the contrast deteriorated.

In the driving method according to the first embodiment shown in FIG. 21, the row selection voltage is applied twice in a pulsed manner, while the column rewrite voltage is the same as the conventional one. In this example, the polarity of each of the pulse voltages applied to the non-rewritable pixels in crosstalks 1 to 3 and 4 to 6 is constant, that is, in crosstalks 1 and 6, one peak is 0 V and the other peak is 0 V. Has the same polarity as VI, the crosstalk 2 and 4 have + VI and the same polarity, and the crosstalk 3 and 5 have the same VI and the same polarity. However, the peak “toe” peak of the rewriting voltage applied to the pixel is half of the rewriting voltage (V2-VI). As a result, the effect was reduced for the purpose of dividing the application of the pulse voltage from one force to several times, which had good contrast.

In the driving method according to the second embodiment shown in FIG. 22, the row Z column is set as a synchronized pulse train, and the pulse for selecting the row, particularly, the pulse is removed. When the noise voltage is not 1Z2 of the driving voltage, the applied voltage when the pulse is removed may not be 0V. In this example, the polarity is constant in all of the crosstalks 1 to 3 and 4 to 6 applied to the non-rewritable pixels, that is, the crosstalk 1 and 6 have a constant polarity of 0 V, and the crosstalk is constant. In Talks 2 and 4, one peak is + V and the other peak is 0V, and the polarity is constant, and in Crosstalks 3 and 5, one peak is 0V and the other peak is 1VI, and the polarity is constant. In the second embodiment, the magnitude of the rewrite voltage peak “toe” peak is twice as large as that of the first embodiment, while the effect of the crosstalk remains the same as that of the first embodiment. As a result, the rewriting of the rewritten pixels can be performed effectively, and the non-rewritten pixels can be prevented from changing due to the influence of crosstalk. <Example 3>

In the driving method according to the third embodiment shown in FIG. 23, the row (scanning) driving voltage and the column driving voltage are configured by pulse trains having the same cycle and the same duty, respectively. Invert the phase of each pulse train. In this example, the polarity of crosstalks 1 to 3 and 4 to 6 applied to the non-rewritable pixel has a constant polarity. That is, in crosstalks 1 and 6, one peak is 0 V and the other peak is —VI and polarity. In crosstalk 2 and 4, one peak is + V and the other peak power S0V is constant, and in crosstalk 3 and 5, one peak is 0V and the other peak is —VI and polarity Is constant. In the third embodiment, the magnitude of the rewriting voltage peak “toe” peak is three times larger than that of the first embodiment, while maintaining the effect of the first and second embodiments with respect to the influence of crosstalk. As a result, the rewriting of the rewritten pixel can be performed more effectively, and the change of the non-rewritten pixel due to the influence of the crosstalk can be more preferably prevented.

[0109] In Examples 1 to 3 and Comparative Example 1 described above, the force that determines the sign of the voltage applied based on 0V is not necessary for the information display device of the present invention to be driven with the reference being 0V. No. In that case, it is only necessary to define whether the reference voltage is constant on the positive side or constant on the negative side with respect to the reference voltage that is not positive or negative with reference to 0V. In addition, the bias voltage applied to the unselected row is set to VI (= (V2) / 2) and half of the rewrite voltage V2 applied to the column. However, the present invention is not limited to this. For example, the bias voltage VI may be set to (( V2) Z3) can also be used.

[0110] <Confirmation of effect>

A test pattern is displayed on the simple matrix panel shown in FIG. 24 (a) with 320 lines on the row (scanning) side and 320 lines on the column side driven by the driving method shown in the above-described Examples 1 to 3 and Comparative Example 1. The reflectivity of the rewrite (no crosstalk) area and the crosstalk area (crosstalk 4 to 6 above) shown in FIG. 24 (b) was measured with an optical densitometer (RD-1 manufactured by Dareta Macbeth). The driving conditions were as follows. That is, the number of times of applying the rewriting voltage to one pixel = 8, the driving was performed with the driving voltage that maximizes the contrast and the influence of the crosstalk 4 was the least, and the unselected column Z row was biased with the driving voltage of 1Z2. The results are shown in Table 2 below.

[0111] [Table 2] Measurement point Comparative example 1 Example 1 Example 2 Example 3 Crosstalk 5 1% 1% 2.5% 2.5% (difference from rewriting)

Cross talk 4 7% 1% 3% 3% (difference from non-rewritable)

Cross talk 60.5% 0.5% 0% 0.5% (difference from non-rewritable)

Display state after rewriting Contrast Contrast Contrast Contrast good It was also noticeable. Was not noticeable. Did not.

won.

[0112] From the results in Table 2, it can be seen that Examples 1 to 3 in which the pulse voltages in the crosstalks 1 to 3 and 4 to 6 applied to the non-rewriting pixels have a constant polarity are applied to the non-rewriting pixels. In the crosstalks 2 and 4, it can be seen that the polarity of the pulse-like voltage is not constant and that the crosstalk is less noticeable than in the comparative example 1, as compared with the comparative example 1. Comparing Examples 1 to 3, it can be seen that the larger the magnitude of the rewrite voltage peak 'toe' peak, the smaller the density change and the less noticeable the crosstalk. Industrial applicability

[0113] The information display panel and the information display device to which the driving method of the present invention is applied include a display unit of a mopile device such as a notebook computer, a PDA, a mobile phone, a handy terminal, an electronic book such as an electronic book, and an electronic newspaper. Signboards, posters, bulletin boards such as blackboards, calculators, displays for home appliances, automotive supplies, etc., card displays for point cards, IC cards, etc., electronic advertisements, electronic POP, electronic price tags, electronic shelf labels, electronic music scores, RF — Appropriately used for the display of ID devices.

Claims

The scope of the claims

[1] At least two types of display media having a first color and a second color are encapsulated between two opposing substrates, at least one of which is transparent, and the display media are separated from electrodes provided on each substrate side. In an information display device driving method for displaying information such as an image by applying an electric field to a display medium and moving the display medium, a row electrode composed of a plurality of electrodes extending in a row direction on one substrate and the other. To display information such as an image on a single screen by applying a voltage by scanning from one end of the row electrode to the other end of a row electrode with a plurality of electrodes extending in the column direction on the substrate After the display of one screen is completed, a voltage that causes crosstalk in the first color and a voltage that causes crosstalk in the second color should be applied at least once to all cells in the display unit. A method for driving an information display device, comprising:

[2] At least two lines are added at the end of the scan, and after one scan is completed, driving is performed to display the first color display and the second color display at least once each. Display device driving method.

[3] The image erasing method prior to image display can be either a line erasing method in which the image is erased line by line and then the image is written line by line, or a total erasing method in which the entire image is erased and the image is erased line by line. 3. The method for driving an information display device according to claim 1, wherein:

[4] At least two types of display media of the first color and the second color are sealed between two opposing substrates, at least one of which is transparent, and an electric field is applied from the electrode to the display medium, According to a driving method of an information display device that moves a display medium to display information such as an image, a driving voltage applied to an electrode for generating an electric field is a driving voltage in an on state and a driving voltage in an off state. A method for driving an information display device, comprising applying a pulse-like voltage composed of a plurality of voltages with a voltage equal to or lower than a threshold value at which a medium starts moving.

5. The method of driving an information display device according to claim 4, wherein the duty ratio of the pulsed voltage (= pulse width Z (pulse width + time in the off state)) is 0.9 or less.

[6] The driving method of the information display device according to [4], wherein the off-state time is 0.1 msec or more.

[7] An information display that encloses a display medium between two opposing substrates, at least one of which is transparent, applies an electric field from the electrodes to the display medium, moves the display medium, and displays information such as an image. In the device driving method, a driving waveform is applied such that a pulse is applied a plurality of times during one pixel rewriting, and the polarity of a crosstalk voltage applied to a non-rewriting pixel does not change during one pixel rewriting. A method for driving an information display device, characterized in that:

[8] The information display device according to claim 7, wherein the interval between the peaks in the pulse voltage applied to the rewrite pixel is widened while applying the pulse a plurality of times in one pixel rewrite. Drive method.

[9] The row (scanning) drive voltage and column drive voltage are composed of pulse trains of the same cycle and duty, respectively, and when selecting a row on the row side, the phases of the respective pulse trains of the row drive voltage and the column drive voltage are inverted. 9. The method for driving an information display device according to claim 8, wherein: