JP5505119B2 - Display device and electronic device - Google Patents

Description

  The present invention relates to a display device and an electronic apparatus.

For example, an electrophoretic display using particle electrophoresis is known as an image display unit of electronic paper (see, for example, Patent Document 1). The electrophoretic display has excellent portability and power saving, and is particularly suitable as an image display unit for electronic paper.
Patent Document 1 has a plurality of cells, two electrodes (upper electrodes) provided on one side (upper side) of each cell, and a lower electrode provided on the other side (lower side) of each cell. A display device is disclosed. Each cell is filled with a dispersion liquid in which three kinds of particles are dispersed in a dispersion medium. The three types of particles include negatively charged black first particles, negatively charged yellow second particles, and positively charged white third particles.
In such a display device of Patent Document 1, by controlling the voltage pattern applied between the three electrodes, a black display state in which the first particles gather on the upper electrode side, and the second particles on the upper electrode. Either the collected yellow display state or the white display state in which the third particles are collected on the upper electrode side can be used.

  However, in the display device of Patent Document 1, since the black first particles are gathered on the upper electrode side together with the yellow second particles in the yellow display state, the black color affects the bright yellow, that is, The original color of the second particle cannot be displayed. Further, in the black display state, the yellow second particles are gathered on the upper electrode side together with the black first particles. Therefore, the black is low in saturation and low in brightness due to yellow, that is, the first particles. The original color of the particles cannot be displayed. That is, in the display device of Patent Document 1, the contrast is lowered, and the lightness / saturation of the chromatic color (yellow) is lowered, which causes a problem that excellent display characteristics cannot be exhibited.

JP 2009-192637 A

  An object of the present invention is to provide a display device capable of exhibiting high contrast and capable of performing vivid color display and an electronic apparatus using the display device.

Such an object is achieved by the present invention described below.
The display device of the present invention includes a storage unit that stores first particles that are positively charged, and second particles that are negatively charged and have a color complementary to the color of the first particles. A display layer;
On one surface side of the display layer, a first electrode and a second electrode provided corresponding to the housing portion are provided,
A predetermined voltage is applied between the first electrode and the second electrode, and the first particles and the second particles are mixed with each other and gathered on the one surface side of the display layer. with mixed state, configured to black is the color mixing of the one said color in said housing portion which is visible from the side of the first color and the second particles of the particles of the display layer And
In the mixed state step, a voltage is applied between the first electrode and the second electrode so that the first electrode has a negative potential and the second electrode has a positive potential. A first step of collecting the first particles on one electrode side and collecting the second particles on the second electrode side, and between the first electrode and the second electrode, A voltage at which one electrode has a positive potential and the second electrode has a negative potential is applied to move the first particles to the second electrode side, and the second particles are moved to the first electrode. And a second step of bringing the mixture into the mixed state by moving it to the electrode side .

  Thus, by mixing the first particles and the second particles and displaying black, it is possible to display black with low brightness and low saturation. In addition, as long as black can be displayed without using black particles, black particles need not be used. Therefore, black particles have an adverse effect on color display (causes a decrease in saturation and brightness). Therefore, a clearer and more vivid color (the color of the first particles and the color of the second particles) can be displayed. Therefore, it is possible to provide a display device that can exhibit high contrast and perform vivid color display.

The display device of the present invention includes a storage unit that stores first particles that are positively charged, and second particles that are negatively charged and have a color complementary to the color of the first particles. A display layer;
On one surface side of the display layer, a first electrode and a second electrode provided corresponding to the housing portion are provided,
A predetermined voltage is applied between the first electrode and the second electrode, and the first particles and the second particles are mixed with each other and gathered on the one surface side of the display layer. By setting it as a mixed state, the color in the said accommodating part visually recognized from the said one surface side of the said display layer is set to black which is a color mixture of the color of the said 1st particle, and the color of the said 2nd particle. And
In the mixed state step, a voltage is applied between the first electrode and the second electrode so that the first electrode has a negative potential and the second electrode has a positive potential. A first step of collecting the first particles on one electrode side and collecting the second particles on the second electrode side, and applying an alternating voltage between the first electrode and the second electrode. And a second step of bringing the first particles and the second particles into the mixed state by vibrating the first particles and the second particles in a direction away from the first electrode and the second electrode. It is characterized by being.

In the display device of the present invention, the alternating voltage is such that the first electrode has a negative potential and the second electrode has a negative potential, compared to a period in which the first electrode has a positive potential and the second electrode has a negative potential. It is preferable that the period of positive potential is longer.
As a result, when the first particle vibrates, the moving distance to the second electrode side becomes longer than the moving distance to the first electrode side. Similarly, the second particle During the vibration, the moving distance to the first electrode side is longer than the moving distance to the second electrode side. As a result, the first particles can be moved from the first electrode side to the second electrode side, and the second particles can be moved more efficiently (smoothly) from the second electrode side to the first electrode side. It is possible to obtain a mixed state in which the first particles and the second particles are more uniformly mixed. Therefore, it is possible to display black with lower saturation and lower brightness.

In the display device according to the aspect of the invention, the alternating voltage includes a period in which the first electrode has a positive potential and the second electrode has a negative potential, the first electrode has a negative potential, and the second electrode has a positive potential. It is preferable that there is a period in which a potential difference is 0 (zero) between the first electrode and the second electrode between the period of potential.
Thereby, the 1st particle and the 2nd particle can be vibrated more effectively.

In the display device according to the aspect of the invention, it is preferable that the first particles and the second particles are dispersed in the accommodating portion prior to the mixing state.
Thereby, since the movement of the first particles and the second particles can be performed smoothly, the first particles A are directed toward the first electrode, and the second particles are rapidly moved toward the second electrode. be able to. As a result, a black display state can be quickly achieved.

In the display device of the present invention, on the other surface side of the display layer, it has a first back surface side electrode and a second back surface side electrode provided corresponding to the housing portion,
Applying an alternating voltage between at least one of the first back electrode and the second back electrode and at least one of the first electrode and the second electrode; It is preferable that the dispersed state is obtained by vibrating the first particles and the second particles in the thickness direction of the display layer.
Thereby, it can be set as a dispersed state smoothly.

In the display device according to the aspect of the invention, the first back surface side electrode and the second back surface side electrode, and the first back surface side electrode and the second back electrode are interposed between the first back surface side electrode and the second back electrode. The first particles are applied to the first electrode and the second electrode side by applying a voltage at which the second back surface side electrode has a positive potential and the first electrode and the second electrode have a negative potential. Collecting and collecting the second particles on the first back surface side electrode and the second back surface side electrode side allows the color in the housing portion to be visually recognized from the one surface side of the display layer. The color of one particle is preferable.
Thereby, the color of the first particles can be displayed. In addition, since the second particles are gathered on the back surface side electrode, the color of the second particles can be suppressed from affecting the display color, and the original color of the first particles can be displayed. .

In the display device according to the aspect of the invention, the first back surface side electrode and the second back surface side electrode, and the first back surface side electrode and the second back electrode are interposed between the first back surface side electrode and the second back electrode. The second particle is applied to the first electrode and the second electrode side by applying a voltage at which the second back surface side electrode has a negative potential and the first electrode and the second electrode have a positive potential. Collecting and collecting the first particles on the first back surface side electrode and the second back surface side electrode side allows the color in the housing portion to be visually recognized from the one surface side of the display layer. It is preferable to set the color of the second particle.
Thereby, the color of the second particle can be displayed. In addition, since the first particles are gathered on the back side electrode, the color of the first particles can be suppressed from affecting the display color, and the original color of the first particles can be displayed. .

In the display device according to the aspect of the invention, it is preferable that the storage portion further stores non-charged white third particles.
As a result, white display is possible, and the contrast can be improved.
In the display device of the present invention, on the other surface side of the display layer, it has a first back surface side electrode and a second back surface side electrode provided corresponding to the housing portion,
Between the first back-side electrode and the second back-side electrode, and applying the first of the back side electrode negative potential, the voltage which the second back-side electrode has a positive potential, the third By collecting the first particles on the first back surface side electrode side and collecting the second particles on the second back surface side electrode side while dispersing the particles in the container, the display It is preferable that the color in the accommodating part visually recognized from the one surface side of the layer is white.
Thereby, the external light incident in the accommodating portion can be efficiently reflected and diffused by the third particles. For example, the third particles are unevenly distributed on the first electrode side and the second electrode side. Therefore, a brighter white color can be displayed as compared with the case where white color is displayed. As a result, higher contrast can be exhibited.

In the display device of the present invention, one pixel is constituted by at least three of the accommodating portions,
One of the first particles and the second particles accommodated in the first accommodating portion included in the at least three accommodating portions is red, the other is cyan, and the one is accommodated in the second accommodating portion. One of the first particles and the second particles is green, the other is magenta, one of the first particles and the second particles housed in the third housing portion is blue, and the other is yellow It is preferable to do it.
This enables full color display.
An electronic apparatus according to the present invention includes the display device according to the present invention.
As a result, it is possible to provide an electronic device that can exhibit high contrast and can perform vivid color display.

It is sectional drawing which shows typically 1st Embodiment of the display apparatus of this invention. It is a top view of the display apparatus shown in FIG. It is a top view which shows the modification of the display surface side electrode shown in FIG. It is a figure which shows the operating voltage of the display apparatus shown in FIG. It is a schematic diagram explaining the action | operation of the display apparatus shown in FIG. It is a schematic diagram explaining the action | operation of the display apparatus shown in FIG. It is a figure which shows the operating voltage of the display apparatus shown in FIG. It is a figure which shows the operating voltage of the display apparatus shown in FIG. It is a figure which shows the operating voltage of the display apparatus shown in FIG. It is a schematic diagram explaining the action | operation of the display apparatus shown in FIG. It is a figure which shows the operating voltage of the display apparatus shown in FIG. It is a schematic diagram explaining the action | operation of the display apparatus shown in FIG. It is a schematic diagram explaining the action | operation of the display apparatus shown in FIG. It is sectional drawing which shows typically 2nd Embodiment of the display apparatus of this invention. It is a perspective view which shows embodiment at the time of applying the electronic device of this invention to electronic paper. It is a figure which shows embodiment at the time of applying the electronic device of this invention to a display.

Hereinafter, a display device and an electronic apparatus of the present invention will be described in detail based on preferred embodiments shown in the accompanying drawings.
<First Embodiment>
First, a first embodiment of the display device of the present invention will be described.
1 is a cross-sectional view schematically showing a first embodiment of the display device of the present invention, FIG. 2 is a plan view of the display device shown in FIG. 1, and FIG. 3 is a modification of the display surface side electrode shown in FIG. FIG. 4, FIG. 7, FIG. 8, FIG. 9, and FIG. 11 are diagrams showing operating voltages of the display device shown in FIG. 1, and FIG. 5, FIG. 6, FIG. 13 is a schematic diagram for explaining the operation of the display device shown in FIG. In the following description, for convenience of explanation, the upper side in FIG. 1 will be described as “upper” and the lower side as “lower”.

1. Configuration of Display Device A display device 1 shown in FIG. 1 includes a display sheet (front plane) 2 and a circuit board (back plane) 9.
The display sheet 2 includes a substrate 3 and a display layer 5 provided on the lower surface of the substrate 3. The substrate 3 includes a sheet-like (flat plate-like) base 31 and a plurality of display surface side electrodes 32 formed on the lower surface of the base 31.
One circuit board 9 includes a sheet-like (flat plate-like) base 91, a circuit (not shown) including a switching element such as a TFT provided on the base 91, and a plurality of back-side electrodes connected to the switching element. 92.

Hereinafter, each of these parts will be described in detail.
-Display layer-
The display layer 5 has a plurality of cells (accommodating portions) 51 in which the dispersion liquid 10 is enclosed. In the present embodiment, the plurality of cells 51 are arranged in a matrix. In the present embodiment, one cell 51 constitutes one pixel. The plurality of cells 51 may be arranged in a honeycomb shape, for example.

  The display layer 5 is in the form of a sheet, and includes a base 52 having a plurality of recesses 521 opened on the upper surface (one surface), and a lid 53 that is liquid-tightly bonded to the base 52 so as to close the recesses 521. Have. A space defined by the inner surface of the recess 521 and the lower surface of the lid 53 constitutes the cell 51. The lid 53 is substantially colorless and transparent, and the inside of the cell 51 can be visually recognized through the lid 53.

Each of the base 52 and the lid 53 has insulating properties and impermeability of the dispersion liquid 10. The constituent materials of the base 52 and the lid 53 are not particularly limited, for example, polyolefins such as polyethylene, polypropylene, and ethylene-vinyl acetate copolymer, modified polyolefins, polyamides (eg, nylon 6, nylon 66), styrene Type, polyvinyl chloride, polyurethane, polyester, epoxy, fluororubber, chlorinated polyethylene and other thermoplastic elastomers, or copolymers, blends, polymer alloys, etc. One of these materials may be used, or a mixture of two or more materials may be used.
The dispersion liquid 10 enclosed in each cell 51 is obtained by dispersing three types of particles (first particle A, second particle B, and third particle C) in the dispersion medium 6.

  The dispersion medium 6 is preferably substantially colorless and transparent. The dispersion medium 6 preferably has a relatively high insulating property. Examples of the dispersion medium 6 include alcohols such as methanol, ethanol and butanol, cellosolves such as methyl cellosolve, esters such as methyl acetate and ethyl acetate, ketones such as acetone and methyl ethyl ketone, and aliphatic carbonization such as pentane. Hydrogen, cycloaliphatic hydrocarbons such as cyclohexane, aromatic hydrocarbons such as benzene having a long-chain alkyl group such as benzene and toluene, halogenated hydrocarbons such as methylene chloride and chloroform, pyridine , Aromatic heterocycles such as pyrazine, nitriles such as acetonitrile and propionitrile, amides such as N, N-dimethylformamide, mineral oils such as carboxylates and liquid paraffin, linoleic acid, linolenic acid, olein Vegetable oils such as acids, dimethyl silicone oil, methyl phenyl silicone Yl, silicone oils such as methyl hydrogen silicone oil, fluorine-based liquid, or other various oils such as hydrofluoroether and the like, these can be used alone or as a mixture.

  Further, in the dispersion medium 6, if necessary, for example, a charge control agent composed of particles of electrolyte, surfactant, metal soap, resin material, rubber material, oils, varnish, compound, etc., titanium-based coupling You may make it add various additives, such as dispersing agents, lubricants, stabilizers, such as an agent, an aluminum coupling agent, and a silane coupling agent.

In such a dispersion medium 6, as described above, the first particles A, the second particles B, and the third particles C are dispersed.
The first particle A is a positively charged positively charged particle, the second particle B is a negatively charged negatively charged particle, and the third particle is an uncharged particle that is not substantially charged. . Of these three types of particles, the first particle A and the second particle B are both charged particles, and therefore are generated between the display surface side electrode 32 and the back surface side electrode 92 as described later. The dispersion medium 6 is electrophoresed (moved) in accordance with the electric field. On the other hand, since the third particles C have no charge, they are dispersed in the dispersion medium 6 regardless of whether or not an electric field is generated between the display surface side electrode 32 and the back surface side electrode 92. To maintain.

The first particle A, the second particle B, and the third particle C are different in color from each other.
The third particles C are white. In this way, by setting the third particles C, which are non-charged particles, to be white, a brighter white color can be displayed as will be described later.
The first particles A and the second particles B have colors complementary to each other. Thereby, as described later, black can be displayed using the first particles A and the second particles B. Specifically, one of the first particle A and the second particle B may be red, the other may be very cyan, one may be green, the other may be magenta, one is blue, and the other is yellow. Also good.

In the following, for the convenience of explanation, a configuration in which the first particle A is red and the second particle B is cyan will be representatively described.
As the first particle A, the second particle B, and the third particle C, any particles can be used as long as they are positively charged, negatively charged, and uncharged. At least one of resin particles, ceramic particles, metal particles, metal oxide particles, or composite particles thereof is preferably used. These particles have the advantage that they are easy to manufacture and the charge can be controlled relatively easily.

  Examples of pigments constituting the pigment particles include black pigments such as aniline black, carbon black, and titanium black, white pigments such as titanium dioxide, antimony trioxide, zinc sulfide, and zinc white, and azo series such as monoazo, disazo, and polyazo. Pigments, yellow pigments such as isoindolinone, yellow lead, yellow iron oxide, cadmium yellow and titanium yellow, azo pigments such as monoazo, disazo and polyazo, red pigments such as quinacridone red and chrome vermilion, phthalocyanine blue and indanthrene Blue pigments such as blue, bitumen, ultramarine, and cobalt blue, green pigments such as phthalocyanine green, and the like can be used, and one or more of these can be used in combination.

Examples of the resin material constituting the resin particles include acrylic resin, urethane resin, urea resin, epoxy resin, rosin resin, polystyrene, polyester, AS resin copolymerized with styrene and acrylonitrile, and the like. These can be used alone or in combination of two or more.
The composite particles are, for example, composed of pigment particles whose surfaces are coated with a resin material, resin particles whose surfaces are coated with a pigment, or a mixture of a pigment and a resin material mixed in an appropriate composition ratio. Particles and the like.

  In addition, for the purpose of improving the dispersibility of the first particles A, the second particles B, and the third particles C in the dispersion medium 6, the surface of each particle A to C is phased with the dispersion medium 6. Highly soluble polymers can be physically adsorbed or chemically bonded. Among these, those in which the polymer is chemically bonded are particularly preferable in view of the problem of detachment from the surface of each particle A to C. With such a configuration, it is possible to improve the affinity, that is, dispersibility, of the particles A to C in the dispersion medium 6 by acting in a direction in which the apparent specific gravity of each particle A to C decreases.

  The average particle diameters of the first particle A, the second particle B, and the third particle C are not particularly limited, but are preferably about 0.1 to 10 μm, preferably about 0.1 to 7.5 μm. It is more preferable that If the average particle size of each of the particles A to C is too small, a sufficient concealment rate cannot be obtained mainly in the visible light range, and as a result, the display contrast of the display device 1 may be reduced. On the other hand, if the average particle size of each of the particles A to C is too large, depending on the type or the like, the particles may easily settle in the dispersion medium 6 and may cause problems such as deterioration in display quality of the display device 1. . The “average particle diameter” means a volume average particle diameter measured with a dynamic light scattering particle size distribution analyzer (for example, product name: LB-500, manufactured by Horiba, Ltd.).

  The specific gravity of the first particle A, the second particle B, and the third particle C is preferably set to be approximately equal to the specific gravity of the dispersion medium 6. As a result, each of the particles A to C may stay in a certain position in the dispersion medium 6 for a long time even after application of voltage between the display surface side electrode 32 and the back surface side electrode 92 is stopped. it can. That is, the display device 1 is provided with a memory property, and the displayed information can be held for a long time. Thereby, the power saving of the display apparatus 1 can be achieved.

The display layer 5 has been described above.
A substrate 3 is provided on the upper surface of the display layer 5, and a circuit board 9 is provided on the lower surface. That is, the display layer 5 is sandwiched between the substrate 3 and the circuit substrate 9. As described above, the substrate 3 includes the sheet-like base portion 31 and the plurality of display surface side electrodes 32 provided on the lower surface of the base portion 31 (the surface on the display layer 5 side). And a plurality of back surface side electrodes 92 provided on the upper surface (surface on the display layer 5 side) of the base portion 91.

In the present embodiment, the upper surface of the substrate 3 is a display surface (surface on which an image is displayed) 1 a of the display device 1.
The bases 31 and 91 may be either flexible or hard, but are preferably flexible. By using the base portions 31 and 91 having flexibility, the display device 1 having flexibility can be obtained.

  When the bases 31 and 91 are flexible, their constituent materials are, for example, polyesters such as PET (polyethylene terephthalate) and PEN (polyethylene naphthalate), polyolefins such as polyethylene, modified polyolefins, polyamides, Examples thereof include various thermoplastic elastomers such as thermoplastic polyimide, polyether, polyetheretherketone, polyurethane, and chlorinated polyethylene, and copolymers, blends, and polymer alloys mainly composed of these.

The average thicknesses of the base portions 31 and 91 are appropriately set depending on the constituent material, application, etc., and are not particularly limited. However, when having flexibility, it is preferably about 20 μm or more and 500 μm or less. More preferably, it is about 25 μm or more and 250 μm or less. Thereby, size reduction (thinning) of the display apparatus 1 can be achieved, aiming at harmony with the softness | flexibility and intensity | strength of the display apparatus 1. FIG.
The plurality of display surface side electrodes 32 formed on the base 31 are provided in a matrix (matrix). The plurality of display surface side electrodes 32 are provided so that two display surface side electrodes 32 (that is, two display surface side electrodes 32 for one cell 51) are positioned on each cell 51. .

On the other hand, the plurality of back surface side electrodes 92 formed on the base 91 are also provided in a matrix (matrix). The plurality of back surface side electrodes 92 are provided such that two back surface side electrodes 92 (that is, two back surface side electrodes 92 for one cell 51) are positioned on each cell 51.
The constituent material of each display surface side electrode 32 and each back surface side electrode 92 is not particularly limited as long as it is substantially conductive, for example, gold, silver, copper, aluminum, or an alloy containing these. In metal materials such as carbon black, carbon-based materials such as carbon black, electroconductive polymer materials such as polyacetylene, polyfluorene or derivatives thereof, and matrix resins such as polyvinyl alcohol and polycarbonate, NaCl, Cu (CF ₃ SO ₃ ) ₂ Various conductive materials such as ionic conductive polymer materials in which ionic substances such as ionic materials are dispersed, conductive oxide materials such as indium oxide (IO), indium tin oxide (ITO), and fluorine-doped tin oxide (FTO) The material can be used, and one or more of these can be used in combination.

  Here, as shown in FIG. 2, the two display surface side electrodes 32 (32 ′, 32 ″) provided corresponding to one cell 51 have substantially the same shape (rectangular shape), and the short pieces thereof. The two display surface side electrodes 32 ′ and 32 ″ are not limited to this shape and arrangement, although they are provided apart from each other in the direction. For example, if the two display surface side electrodes 32 ′ and 32 ″ are electrically separated, as shown in FIG. 3A, the display surface side electrode 32 is arranged inside the frame-shaped display surface side electrode 32 ′. ”May be provided, or, as shown in FIG. 3B, the cell 51 is divided into two so as to face each other through the display surface side electrode 32 ′ provided in the center portion. The display surface side electrode 32 ″ may be provided. The back surface side electrode 92 is the same as this, and preferably corresponds to the shape and arrangement of the display surface side electrode 32.

2. Operation of the display device The display device 1 operates as follows. Hereinafter, for convenience of explanation, one cell 51 (one pixel) will be described as a representative. One of the two display surface side electrodes 32 provided corresponding to the one cell 51 is referred to as a “display surface side electrode (first electrode) 321”, and the other is referred to as a “display surface side electrode (second electrode). Electrode) 322 ". Similarly, one of the two back surface side electrodes 92 provided corresponding to the one cell 51 is referred to as a “display surface side electrode (first back surface side electrode) 921”, and the other is referred to as a “back surface side electrode (first surface electrode). 2 back side electrode) 922 ".

  The display device 1 can apply voltages independently to four electrodes (display surface side electrodes 321 and 322, back surface side electrodes 921 and 922). In such a display device 1, the uneven distribution positions of the first particles A and the second particles B in the cell 51 are controlled by selecting a voltage pattern to be applied to the four electrodes 321, 322, 921, 922. Thus, a desired color is displayed in the cell 51 (one pixel).

  Specifically, in the display device 1, the cell 51 is displayed in a black display state in which black is displayed on the display surface 1a, a white display state in which white is displayed on the display surface 1a, and a red in which red is displayed on the display surface 1a. A display state or a cyan display state in which cyan is displayed on the display surface 1a can be set. Hereinafter, the black display state, the white display state, the red display state, and the cyan display state will be sequentially described.

−Black display state−
First, the voltage shown in FIG. 4A is applied to the four electrodes 321, 322, 921, and 922. That is, while the back surface side electrodes 921 and 922 are both grounded (0 V), the display surface side electrode 321 has a negative potential (lower potential than the back surface side electrodes 921 and 922) between the display surface side electrodes 321 and 322. A voltage is applied so that the surface-side electrode 322 has a positive potential (higher potential than the back-side electrodes 921 and 922) (first step). Then, the positively charged first particles A move (migrate) toward the display surface side electrode 321 and gather (is unevenly distributed) on the display surface side electrode 321 side. On the other hand, the negatively charged second particles B move toward the display surface side electrode 322 and gather on the display surface side electrode 322 side. Note that the third particles C maintain a state of being dispersed in the dispersion medium 6. Thereby, as shown in FIG. 5, the first particles A and the second particles B are arranged side by side on the display surface 1 a side in the cell 51.

  If the magnitude relationship between the potentials of the display surface side electrodes 321 and 322 and the back surface side electrodes 921 and 922 is maintained (if a similar electric field can be generated), as shown in FIG. The side electrodes 921 and 922 may not be 0V, the display surface side electrode 321 may be −V, and the display surface side electrode 322 may not be + V. For example, the back surface side electrodes 921 and 922 may be + 10V and the display surface side electrode 321 may be The display surface side electrode 322 may be + 15V. The same applies to the voltage described below.

After the state shown in FIG. 5 is reached, the voltage shown in FIG. 4B is applied to the four electrodes 321, 322, 921, and 922. That is, an alternating voltage is applied between the display surface side electrodes 321 and 322 while the back surface side electrodes 921 and 922 are both grounded (0 V) (second step). Then, in a state where the display surface side electrode 321 is a positive potential and the display surface side electrode 322 is a negative potential, the first particles A move toward the display surface side electrode 322 and the second particles B are displayed on the display surface side. In contrast, when the display surface side electrode 321 is a negative potential and the display surface side electrode 322 is a positive potential, the first particles A move toward the display surface side electrode 321, The second particles B move toward the display surface side electrode 322.
As a result, the first particles A and the second particles B vibrate in the separation direction of the display surface side electrodes 321 and 322 (the surface direction of the display layer 5 and the horizontal direction in FIG. 5). As a result, as shown in FIG. 6, the first particles A and the second particles B are mixed with each other and are unevenly distributed on the display surface 1 a side in the cell 51 (hereinafter also referred to as “mixed state”). )

  By setting the cell 51 in such a mixed state, black, which is a mixed color of the color of the first particle A and the color of the second particle B, is displayed on the display surface 1a. In particular, when the first particles A and the second particles B are mixed, for example, as compared with the state where the first particles A and the second particles B shown in FIG. Black with low brightness and low brightness can be displayed. Therefore, the display device 1 can exhibit higher contrast.

Here, as shown in FIG. 4B, the alternating voltage (waveform) applied between the display surface side electrodes 321 and 322 to obtain a mixed state is not particularly limited, but the display surface side electrode 321 has a positive potential, The period T1 in which the display surface side electrode 322 is at a negative potential is preferably a voltage that is longer than the period T2 in which the display surface side electrode 321 is at a negative potential and the display surface side electrode 322 is at a positive potential.
As a result, when the first particle A vibrates, the moving distance to the display surface side electrode 322 side becomes longer than the moving distance to the display surface side electrode 321 side. In B, during the vibration, the moving distance to the display surface side electrode 321 side becomes longer than the moving distance to the display surface side electrode 322 side. As a result, the first particles A are efficiently (smoothly) transferred from the display surface side electrode 321 side to the display surface side electrode 322 side, and the second particles B are transferred from the display surface side electrode 322 side to the display surface side electrode 321 side. It can be made to move, and it can be set as the mixed state which the 1st particle A and the 2nd particle B mixed more uniformly. Accordingly, it is possible to display black with lower saturation and lower brightness.

Note that the relationship between the lengths of the periods T1 and T2 is not particularly limited, but the period T1 is preferably about 1.5T2 or more and about 5.0T2 or less. By making the period T1 1.5T2 or more, the above effects can be effectively exhibited, and by making the period T1 5.0T2 or less, the reduction in the frequency per unit time can be suppressed. it can.
The application time of the period T1 is not particularly limited, but is preferably 50 to 500 ms. The application time of the period T2 is not particularly limited, but is 20 to 100 ms (however, shorter than the application time of the period T1). Is preferred. Thereby, the effect becomes more remarkable.

  Further, as shown in FIG. 4B, the alternating voltage applied between the display surface side electrodes 321 and 322 to obtain a mixed state is such that the display surface side electrode 321 has a positive potential and the display surface side electrode 322 has a negative potential. The period during which the display surface side electrodes 321 and 322 are at the same potential (state where the potential difference is 0) between the period T1 during which the display surface side electrode 321 is negative potential and the display surface side electrode 322 is positive potential. It preferably has T3. By having such a period T3, the first particles A and the second particles B can be vibrated more effectively. Specifically, when an electric field acts on the first particles A and the second particles B, these particles are dielectrically polarized, and the dielectrically polarized particles are adsorbed by electrostatic force. By interposing the period T3 between the period T1 and the period T2, the dielectric polarization of the particles A and B is released, whereby the particles are separated from each other and each particle is easily moved. Therefore, the 1st particle A and the 2nd particle B can be vibrated effectively, and can be made into a mixed state rapidly.

  4B, during the period T1 in which the display surface side electrode 321 is positive potential and the display surface side electrode 322 is negative potential, the display surface side electrode 321 is negative potential and the display surface side electrode 322 is By making the period longer than the positive potential period T2, more uniform mixing of the first particles A and the second particles B is realized. Another method is as follows. That is, as shown in FIG. 7B, the lengths of the period T1 and the period T2 are the same, but a voltage at which the electric field in the period T1 is stronger (larger) than the electric field in the period T2 is displayed. You may apply between 321 and 322. As a result, when the first particle A vibrates, the moving distance to the display surface side electrode 322 side becomes longer than the moving distance to the display surface side electrode 321 side. In B, during the vibration, the moving distance to the display surface side electrode 321 side becomes longer than the moving distance to the display surface side electrode 322 side. As a result, the first particles A are efficiently (smoothly) transferred from the display surface side electrode 321 side to the display surface side electrode 322 side, and the second particles B are transferred from the display surface side electrode 322 side to the display surface side electrode 321 side. The first particles A and the second particles B can be mixed more uniformly.

  Further, in order to change from the state shown in FIG. 5 to the state shown in FIG. 6, the voltage applied between the display surface side electrodes 321 and 322 is not limited to the alternating voltage as described above. For example, FIG. As shown, the display surface side electrode 321 may be a positive potential and the display surface side electrode 322 may be a direct current voltage having a negative potential. Also by this voltage, the second particles B can be moved to the display surface side electrode 321 side while moving the first particles A to the display surface side electrode 322 side. The particles B can be mixed with each other. Note that the voltage shown in FIG. 7A may be applied only once between the display surface side electrodes 321 and 322, or may be applied multiple times in a pulsed manner.

The black display state has been described above.
Here, prior to the black display state, the first particles A, the second particles B, and the third particles C are dispersed in the dispersion medium 6 (the state shown in FIG. The state is also referred to as “dispersed state”). In other words, it is preferable to set the black display state after the dispersion state. Since the first particles A and the second particles B can move smoothly by being in a dispersed state, when the voltage shown in FIG. 4A is applied, the first particles A are displayed on the display surface side electrode. The second particles B can be quickly moved toward the display surface side electrode 322 toward the direction 321.

For example, the voltage shown in FIG. 8 is applied to the four electrodes 321, 322, 921, and 922 for the dispersion state. That is, an alternating voltage is applied between the display surface side electrodes 321 and 322 and the back surface side electrodes 921 and 922. Then, when the display surface side electrodes 321 and 322 are at a positive potential and the back surface side electrodes 921 and 922 are at a negative potential, the first particles A move toward the back surface side electrodes 921 and 922 and the second particles B Moves toward the display surface side electrodes 321 and 322. Conversely, when the display surface side electrodes 321 and 322 are at a negative potential and the back surface side electrodes 921 and 922 are at a positive potential, the first particles A are on the display surface side. While moving toward the electrodes 321 and 322, the second particles B move toward the back side electrodes 921 and 922. In addition, the 3rd particle | grains C are not influenced by the application of a voltage, but maintain the state disperse | distributed in the dispersion medium 6. FIG.
Thereby, the first particles A and the second particles B vibrate in the separation direction of the display surface side electrodes 321 and 322 and the back surface side electrodes 921 and 922 (the thickness direction of the display layer 5 and the vertical direction in FIG. 1). To do. As a result, the first particles A, the second particles B, and the third particles can be dispersed in the dispersion medium 6, respectively.

  As shown in FIG. 8, the alternating voltage applied between the display surface side electrodes 321 and 322 and the back surface side electrodes 921 and 922 in order to obtain a dispersed state is that the display surface side electrodes 321 and 322 have a positive potential, the back surface side electrode 921, Between the period T4 in which 922 is a negative potential and the period T5 in which the display surface side electrodes 321 and 322 are a negative potential and the back surface side electrodes 921 and 922 are a positive potential, the display surface side electrodes 321 and 322 and the back surface side electrodes 921 and 922 preferably have a period T6 of the same potential (state where the potential difference is 0). By having such a period T6, the first particles A and the second particles B can be vibrated more effectively for a reason similar to the provision of the period T3, and the dispersed state can be quickly achieved. be able to.

  In FIG. 8, an alternating voltage is applied between the display surface side electrodes 321 and 322 and the back surface side electrodes 921 and 922. However, as described above, the first particles A and the second particles B are displayed. It is only necessary to vibrate in the thickness direction of the layer 5, and an alternating voltage may be applied between at least one of the display surface side electrodes 321 and 322 and at least one of the back surface side electrodes 921 and 922.

However, for example, when an alternating voltage is applied between the display surface side electrode 321 and the back surface side electrode 921 while the display surface side electrode 322 and the back surface side electrode 922 are grounded, the display surface side electrode 321 and the back surface side electrode 921 In addition, an electric field in the thickness direction of the display layer 5 is generated between them, and an electric field in the surface direction of the display layer 5 is generated between the display surface side electrodes 321 and 322 and between the back surface side electrodes 921 and 922. For this reason, depending on the strength of the electric field, the first particles A and the second particles B may not be able to vibrate smoothly in the thickness direction of the display layer 5.
From this point, it is most preferable to apply an alternating voltage between the display surface side electrodes 321 and 322 and the back surface side electrodes 921 and 922 as shown in FIG.

-White display state-
First, the voltage shown in FIG. 9 is applied to the four electrodes 321, 322, 921, and 922. That is, while the display surface side electrodes 321 and 322 are both grounded, a voltage (DC voltage) is applied between the back surface side electrodes 921 and 922 so that the back surface side electrode 921 has a negative potential and the back surface side electrode 922 has a positive potential. . Then, as shown in FIG. 10, the positively charged first particles A move toward the back surface side electrode 921 and gather on the back surface side electrode 921 side. On the other hand, the negatively charged second particles B move toward the back surface side electrode 922 and gather on the back surface side electrode 922 side. Note that the third particles C maintain a state of being dispersed in the dispersion medium 6.
Thereby, when the 3rd particle | grains C disperse | distribute in the cell 51 (dispersion medium 6) and the cell 51 is visually recognized from the display surface 1a side, the 1st particle A and the 2nd particle B become the 3rd particle C. Obscured by. As a result, in such a state, white, which is the color of the third particles C, is displayed on the display surface 1a.

  As shown in FIG. 10, by dispersing the third particles C in the dispersion medium 6, it is possible to efficiently reflect and diffuse external light that has entered the cell 51 through the substrate 3. For example, a brighter white color can be displayed as compared with a case where white color is displayed by unevenly distributing the third particles C toward the display surface side electrodes 321 and 322. As a result, higher contrast can be exhibited.

-Red display status-
The voltage shown in FIG. 11A is applied to the four electrodes 321, 322, 921, and 922. That is, a voltage (DC voltage) is applied between the display surface side electrodes 321 and 322 and the back surface side electrodes 921 and 922 so that the display surface side electrodes 321 and 322 have a negative potential and the back surface side electrodes 921 and 922 have a positive potential. Then, as shown in FIG. 12, the positively charged first particles A move toward the display surface side electrodes 321 and 322 and gather on the display surface side electrodes 321 and 322 side. On the other hand, the negatively charged second particles B move toward the back surface side electrodes 921 and 922 and gather on the back surface side electrodes 921 and 922 side. Note that the third particles C maintain a state of being dispersed in the dispersion medium 6. Thereby, red, which is the color of the first particles A, is displayed on the display surface 1a.

  In the red display state, the second particles B are gathered at the back surface side electrodes 921 and 922 side, that is, at a site far from the display surface 1a, and further between the first particles A and the second particles B. The third particles C are dispersed. Therefore, the external light that has passed between the first particles A can be reflected and diffused by the third particles before reaching the second particles B. As a result, it is possible to prevent (or suppress) the color of the second particles B from affecting the red display state, and it is possible to display a brighter red color.

-Cyan display state-
The voltage shown in FIG. 11B is applied to the four electrodes 321, 322, 921, and 922. That is, a voltage (DC voltage) is applied between the display surface side electrodes 321 and 322 and the back surface side electrodes 921 and 922 so that the display surface side electrodes 321 and 322 have a positive potential and the back surface side electrodes 921 and 922 have a negative potential. Then, as shown in FIG. 13, the positively charged first particles A move toward the back surface side electrodes 921 and 922 and gather on the back surface side electrodes 921 and 922 side. On the other hand, the negatively charged second particles B move toward the display surface side electrodes 321 and 322 and gather on the display surface side electrodes 321 and 322 side. Note that the third particles C maintain a state of being dispersed in the dispersion medium 6. Thereby, cyan which is the color of the second particle B is displayed on the display surface 1a.

  In the cyan display state, the first particles A are gathered at the back surface side electrodes 921 and 922, that is, the portions far from the display surface 1a, and the second particles B and the first particles A 3 particles C are dispersed. Therefore, the external light that has passed between the second particles B can be reflected and diffused by the third particles before reaching the first particles A. As a result, the color of the first particle A can be prevented (or suppressed) from affecting the cyan display state, and brighter cyan can be displayed.

  According to the display device 1 as described above, since black is displayed by mixing the first particles A and the second particles B, it is possible to display black with low brightness and low saturation. . Further, since black can be displayed without using black particles, the color of the first particle A, the color of the second particle B, and the color of the third particle C can be displayed more brightly and vividly. Further, when displaying the color of the first particle A, the second particle B moves to the opposite side, and when displaying the color of the second particle B, the first particle A is on the opposite side. From this point, the colors of the first particles A and the second particles B can be displayed more brightly and vividly. Therefore, the display device 1 can exhibit high contrast and can perform vivid color display.

Second Embodiment
Next, a second embodiment of the display device of the present invention will be described.
FIG. 14 is a cross-sectional view schematically showing a second embodiment of the display device of the present invention.
Hereinafter, the display device according to the second embodiment will be described, but the description will be focused on differences from the above-described embodiment, and description of similar matters will be omitted.

The display device 1A according to the present embodiment has the same configuration as that of the first embodiment described above except that the number of cells constituting one pixel is different.
As shown in FIG. 14, in the display device 1A of the present embodiment, one pixel is configured by three cells 51 (a first cell 51A, a second cell 51B, and a third 51C).
In the first cell 51A, the color of the first particle A is red, and the color of the second particle B is cyan, which has a complementary color relationship with red. In the second cell 51B, the color of the first particle A is green, and the color of the second particle B is magenta having a complementary color relationship with green. In the third cell 51C, the color of the first particle A is blue, and the color of the second particle B is yellow, which is in a complementary color relationship with blue. By configuring one pixel with the first cell 51A, the second cell 51B, and the third cell 51C as described above, the display device 1A can realize full color display.

  Specifically, as described in the first embodiment, the first cell 51A can take four states of a black display state, a white display state, a red display state, and a cyan display state. Similarly, the second cell 51B has four states of a black display state, a white display state, a green display state, and a magenta display state, and the third cell 51C has a black display state, a white display state, and a blue display. Each of the four states of the state and the yellow display state can be taken. Then, by controlling (selecting) a combination of the state of the first cell 51A, the state of the second cell 51B, and the state of the third cell 51C, full color can be displayed on the pixel.

  For each cell 51, the color combination of the first particle A and the second particle B may be reversed. That is, in the first cell 51A, the first particle A may be cyan and the second particle B may be red. In the second cell 51B, the first particle A is magenta. The second particle B may be green, and in the third cell 51C, the first particle A may be yellow and the second particle B may be blue.

  Specific operations of the display device 1A are as shown in Tables 1 and 2. In each table, “W” means a white display state, “BK” means a black display state, “R” means a red display state, and “G” means a green display state. , “B” means blue display state, “C” means cyan display state, “M” means magenta display state, “Y” means yellow display state To do. Moreover, what is shown in each table is an example, and the color that can be displayed on the display device 1A is not limited to this.

-White display-
As shown in Table 1, there are at least three patterns for displaying white on the pixels. Specifically, the pattern (W1) in which each cell 51A, 51B, 51C is in a white display state, the first cell 51A is in a red display state, the second cell 51B is in a green display state, and the third cell A pattern (W2) in which 51C is in a blue display state, and a pattern (W3) in which the first cell 51A is in a cyan display state, the second cell 51B is in a magenta display state, and the third cell 51C is in a yellow display state. And have.
Of these three patterns (W1) to (W3), the pattern (W1) is preferable in that it can display the clearest and bright white color (that is, the white color having the highest reflectance). That is, an image with high contrast can be displayed by displaying white in the pattern (W1).

-Red display-
As shown in Table 1, there are at least seven patterns for displaying red in the pixels. Specifically, the pattern (R1) in which the first cell 51A is in a red display state, the second cell 51B and the third cell 51C are in a white display state, and the first cell 51A is in a red display state. Patterns (R2) and (R3) in which one of the second cell 51B and the third cell 51C is in a white display state and the other is in a black display state, and the first cell 51A is in a red display state, The second cell 51B and the third cell 51C in a black display state (R4), the first cell 51A in a red display state, the second cell 51B in a magenta display state, and the third cell 51C. Is the yellow display state (R5), the first cell 51A is in the white display state, the second cell 51B is in the magenta display state, and the third cell 51C is in the yellow display state. A turn (R6), a first cell 51A and a black display state, the second cell 51B and magenta display state, and a third cell 51C and a pattern (R7) to yellow display state.

Of the patterns (R1) to (R4), the pattern (R1) can display the brightest red, and the pattern (R4) can display the darkest red. The pattern (R2) and the pattern (R3) can display red having brightness intermediate between the pattern (R1) and the pattern (R4).
In addition, the pattern (R5) can display red having the best color (that is, the darkest) among the seven patterns. Specifically, the mixed color of magenta displayed in the second cell 51B and yellow displayed in the third cell 51C is red. For this reason, the red color displayed in the first cell 51A and the red color displayed in the second and third cells 51B and 51C are combined to display a red color with better color.

−Green display−
As shown in Table 1, there are at least seven patterns for displaying the green color on the pixels, similar to the red display pattern described above. Specifically, the pattern (G1) in which the second cell 51B is in the green display state, the first cell 51A and the third cell 51C are in the white display state, and the second cell 51B is in the green display state. Patterns (G2) and (G3) in which one of the first cell 51A and the third cell 51C is in a white display state and the other is in a black display state, and the second cell 51B is in a green display state, The pattern (G4) in which each of the first cell 51A and the third cell 51C is in the black display state, the second cell 51B in the green display state, the first cell 51A in the cyan display state, and the third cell 51C Is a yellow display state pattern (G5), the second cell 51B is a white display state, the first cell 51A is a cyan display state, and the third cell 51C is a yellow display state. And emissions (G6), the second cell 51B and the black display state, the first cell 51A and cyan display state, and a pattern (G7) of the third cell 51C and the yellow display state.

Of the patterns (G1) to (G4), the pattern (G1) can display the brightest green, and the pattern (G4) can display the darkest green. The pattern (G2) and the pattern (G3) can display green having brightness intermediate between the pattern (G1) and the pattern (G4).
In addition, the pattern (G5) can display green having the best color (that is, the darkest) among the seven patterns. Specifically, the mixed color of cyan displayed in the first cell 51A and yellow displayed in the third cell 51C is green. For this reason, the green color displayed in the second cell 51B and the green color displayed in the first and third cells 51A and 51C are combined to display a green color with better hue.

-Blue display-
As shown in Table 1, there are at least seven patterns for displaying a blue color on the pixels, like the red display pattern described above. Specifically, the pattern (B1) in which the third cell 51C is in a blue display state, the first cell 51A and the second cell 51B are in a white display state, and the third cell 51C is in a blue display state. Patterns (B2) and (B3) in which one of the first cell 51A and the second cell 51B is in a white display state and the other is in a black display state, and the third cell 51C is in a blue display state, The pattern (B4) in which each of the first cell 51A and the second cell 51B is in a black display state, the third cell 51C in a blue display state, the first cell 51A in a cyan display state, and the second cell 51B Is a pattern (B5) in which the third cell 51C is in the white display state, the first cell 51A is in the cyan display state, and the second cell 51B is in the magenta display state. And emissions (B6), a third cell 51C and a black display state, the first cell 51A and cyan display state, the second cell 51B and a pattern (B7) to magenta display state.

Of the patterns (B1) to (B4), the pattern (B1) can display the brightest blue color, and the pattern (B4) can display the darkest blue color. The pattern (B2) and the pattern (B3) can display a blue color having intermediate brightness between the pattern (B1) and the pattern (B4).
Further, the pattern (B5) can display blue having the best color (that is, the darkest) among the seven patterns. Specifically, the mixed color of cyan displayed in the first cell 51A and magenta displayed in the second cell 51B is blue. Therefore, when the blue color displayed in the third cell 51C and the blue color displayed in the first and second cells 51A and 51B are combined, a blue color having a better color is displayed.

-Cyan display-
As shown in Table 2, there are at least seven patterns for displaying cyan on the pixels, similar to the red display pattern described above. Specifically, the pattern (C1) in which the first cell 51A is in the cyan display state, the second cell 51B and the third cell 51C are in the white display state, and the first cell 51A is in the cyan display state. Patterns (C2) and (C3) in which one of the second cell 51B and the third cell 51C is in a white display state and the other is in a black display state, and the first cell 51A is in a cyan display state, The pattern (C4) in which each of the second cell 51B and the third cell 51C is in the black display state, the first cell 51A in the cyan display state, the second cell 51B in the green display state, and the third cell 51C (C5) in which the first cell 51A is in the white display state, the second cell 51B is in the green display state, and the third cell 51C is in the blue display state. And C6), the first cell 51A and a black display state, the second cell 51B and green display state, and a pattern (C7) to a third cell 51C and blue display state.

Of the patterns (C1) to (C4), the pattern (C1) can display the lightest cyan, and the pattern (C4) can display the darkest cyan. The pattern (C2) and the pattern (C3) can display cyan having brightness intermediate between the pattern (C1) and the pattern (C4).
Further, the pattern (C5) can display cyan having the best color (that is, the darkest) among the seven patterns. Specifically, the mixed color of green displayed in the second cell 51B and blue displayed in the third cell 51C is cyan. For this reason, the cyan displayed in the first cell 51A and the cyan displayed in the second and third cells 51B and 51C are combined to display cyan having a better hue.

-Magenta display-
As shown in Table 2, there are at least seven patterns for displaying magenta on the pixels, like the red display pattern described above. Specifically, the pattern (M1) in which the second cell 51B is in the magenta display state, the first cell 51A and the third cell 51C are in the white display state, and the second cell 51B is in the magenta display state. Patterns (M2) and (M3) in which one of the first cell 51A and the third cell 51C is in a white display state and the other is in a black display state, and the second cell 51B is in a magenta display state, The pattern (M4) in which each of the first cell 51A and the third cell 51C is in a black display state, the second cell 51B in a magenta display state, the first cell 51A in a red display state, and the third cell 51C Is a blue display state, the second cell 51B is in a white display state, the first cell 51A is in a red display state, and the third cell 51C is in a blue display state. A turn (M6), the second cell 51B and the black display state, the first cell 51A and red display state, and a pattern (M7) to a third cell 51C and blue display state.

Among the patterns (M1) to (M4), magenta with the brightest pattern (M1) can be displayed, and magenta with the darkest pattern (M4) can be displayed. The pattern (M2) and the pattern (M3) can display magenta having an intermediate brightness between the pattern (M1) and the pattern (M4).
The pattern (M5) can display magenta having the best color (ie, the darkest) among the seven patterns. Specifically, the mixed color of red displayed in the first cell 51A and blue displayed in the third cell 51C is magenta. Therefore, the magenta displayed in the second cell 51B and the magenta displayed in the first and third cells 51A and 51C are combined to display magenta with better color.

-Yellow display-
As shown in Table 2, there are at least seven patterns for displaying yellow on the pixels, similar to the red display pattern described above. Specifically, the pattern (Y1) in which the third cell 51C is in the yellow display state, the first cell 51A and the second cell 51B are in the white display state, and the third cell 51C is in the yellow display state. Patterns (Y2) and (Y3) in which one of the first cell 51A and the second cell 51B is in a white display state and the other is in a black display state, and the third cell 51C is in a yellow display state, The pattern (Y4) in which each of the first cell 51A and the second cell 51B is in a black display state, the third cell 51C in a yellow display state, the first cell 51A in a red display state, and the second cell 51B Is the green display state, the third cell 51C is in the white display state, the first cell 51A is in the red display state, and the second cell 51B is in the green display state. A turn (Y6), a third cell 51C and a black display state, the first cell 51A and red display state, and a pattern (Y7) of the second cell 51B and green display state.

Of the patterns (Y1) to (Y4), the pattern (Y1) can display the brightest yellow, and the pattern (Y4) can display the darkest yellow. The pattern (Y2) and the pattern (Y3) can display yellow having an intermediate brightness between the pattern (Y1) and the pattern (Y4).
Further, the pattern (Y5) can display yellow having the best color (that is, the darkest) among the seven patterns. Specifically, the mixed color of red displayed in the first cell 51A and green displayed in the second cell 51B is yellow. For this reason, the yellow displayed in the third cell 51C and the yellow displayed in the first and second cells 51A and 51B are combined to display a yellow having a better hue.

-Black display-
As shown in Table 2, there are at least one pattern for displaying black on the pixels. Specifically, it has a pattern (BK1) in which each cell 51A, 51B, 51C is in a black display state.

-Gray display-
As shown in Table 2, there are at least six patterns for displaying gray on the pixels. Specifically, a pattern (GR1), (GR2) in which any one of the first cell 51A, the second 51B, and the third 51C is in a black display state and the other two cells are in a white display state. ), (GR3), and a pattern (GR4) in which any one of the first cell 51A, the second 51B, and the third 51C is in a white display state, and the other two cells are in a black display state. (GR5) and (GR6).
Of the patterns (GR1) to (GR6), the patterns (GR1), (GR2), and (GR3) are gray near white, and the patterns (GR4), (GR5), and (GR6) are gray near black. .

-Display state of other colors Although not shown in Tables 1 and 2, colors other than those described above can be displayed on the pixels. For example, to display a mixed color of red and green, the first cell 51A is set in a red display state, the second cell 51B is set in a green display state, and the third cell 51C is set in a white display state or a black display state. In order to display a mixed color of green and blue, the second cell 51B is in a green display state, the third cell 51C is in a blue display state, and the first cell 51A is in a white display state or a black display state. In order to display a mixed color of blue and red, the third cell 51C is set in a blue display state, the first cell 51A is set in a red display state, and the second cell 51B is set in a white display state or black. The display state may be set. For example, in order to display a mixed color of cyan and magenta, the first cell 51A is set to the cyan display state, the second cell 51B is set to the magenta display state, and the third cell 51C is set to the white display state or the black display state. In order to display a mixed color of magenta and yellow, the second cell 51B is in the magenta display state, the third cell 51C is in the yellow display state, and the first cell 51A is in the white display state or black. In order to display a mixed color of yellow and cyan, the third cell 51C is set to the yellow display state, the first cell 51A is set to the cyan display state, and the second cell 51B is set to the white display state. Alternatively, a black display state may be set.
According to the second embodiment as described above, the same effect as that of the first embodiment described above can be exhibited.

<Electronic equipment>
The display device 1 as described above can be incorporated into various electronic devices. Hereinafter, the electronic apparatus of the present invention including the display device 1 will be described.
<< Electronic Paper >>
First, an embodiment when the electronic apparatus of the present invention is applied to electronic paper will be described.

FIG. 15 is a perspective view showing an embodiment when the electronic apparatus of the present invention is applied to electronic paper.
An electronic paper 600 shown in FIG. 15 includes a main body 601 composed of a rewritable sheet having the same texture and flexibility as paper, and a display unit 602.
In such electronic paper 600, the display unit 602 includes the display device 1 as described above.

<< Display >>
Next, an embodiment when the electronic apparatus of the present invention is applied to a display will be described.
FIG. 16 is a diagram showing an embodiment when the electronic apparatus of the present invention is applied to a display. 16A is a cross-sectional view, and FIG. 16B is a plan view.
A display (display device) 800 illustrated in FIG. 16 includes a main body 801 and an electronic paper 600 that is detachably provided to the main body 801. The electronic paper 600 has the same configuration as described above, that is, the configuration shown in FIG.

  The main body 801 has an insertion port 805 into which the electronic paper 600 can be inserted on its side (right side in FIG. 16A), and two pairs of conveying rollers 802a and 802b are provided inside. Yes. When the electronic paper 600 is inserted into the main body 801 through the insertion port 805, the electronic paper 600 is installed in the main body 801 in a state of being sandwiched between the pair of conveyance rollers 802a and 802b.

  A rectangular hole 803 is formed on the display surface side of the main body 801 (the front side in FIG. 16B), and a transparent glass plate 804 is fitted in the hole 803. . Thereby, the electronic paper 600 installed in the main body 801 can be viewed from the outside of the main body 801. That is, in the display 800, the display surface is configured by visually recognizing the electronic paper 600 installed in the main body 801 on the transparent glass plate 804.

Further, a terminal portion 806 is provided at the leading end portion (left side in FIG. 16) of the electronic paper 600 in the insertion direction, and the terminal is provided inside the main body portion 801 with the electronic paper 600 installed on the main body portion 801. A socket 807 to which the unit 806 is connected is provided. A controller 808 and an operation unit 809 are electrically connected to the socket 807.
In such a display 800, the electronic paper 600 is detachably installed on the main body 801, and can be carried and used while being detached from the main body 801.

Moreover, in such a display 800, the electronic paper 600 is comprised with the display apparatus 1 as mentioned above.
Note that the electronic apparatus of the present invention is not limited to the application to the above, but, for example, a television, viewfinder type, monitor direct-view type video tape recorder, car navigation device, pager, electronic notebook, calculator. , Electronic newspapers, word processors, personal computers, workstations, videophones, POS terminals, devices equipped with touch panels, and the like. The display device 1 can be applied to the display units of these various electronic devices. is there.

  As described above, the display device and the electronic apparatus according to the present invention have been described based on the illustrated embodiment. However, the present invention is not limited to this, and the configuration of each unit is an arbitrary configuration having the same function. Can be substituted. In addition, any other component may be added to the present invention. Further, the display device of the present invention may be a combination of any two or more configurations of the above embodiments.

In the above-described embodiment, the cell has a substantially rectangular shape in a plan view of the display layer, and the configuration in which the cells are arranged in a matrix has been described. However, the shape and arrangement of the cells are not limited thereto, for example Each cell may have a substantially hexagonal shape in a plan view of the display layer, and may be arranged in a honeycomb shape.
In the above-described embodiment, the case where the white third particles are non-charged particles that are not substantially charged has been described. However, the particles are dispersed in the cell without an electric field acting. If so, charged particles having a positive or negative charge may be used. The third particles may not be white, and may be a metal color such as gold, silver, or copper.
In addition, the above-described embodiment is a so-called partition type (cell type) display device, but is not limited thereto, and a so-called microcapsule type may be used.

  DESCRIPTION OF SYMBOLS 1, 1A ... Display apparatus 1a ... Display surface 2 ... Display sheet 3 ... Substrate 31 ... Base 32, 32 ', 32 ", 321, 322 ... Display side electrode 5 ... Display layer 51 ... Cell 51A ... 1st cell 51B ... 2nd cell 51C ... 3rd cell 52 ... Base 521 ... Recess 53 ... Lid 6 ... Dispersion medium 9 ... Circuit board 91 ... Base 92 , 921, 922 ... Back side electrode 10 ... Dispersion liquid 600 ... Electronic paper 601 ... Main unit 602 ... Display unit 800 ... Display 801 ... Main unit 802a, 802b ... Conveying roller pair 803 ... Hole 804 ... Transparent glass plate 805 ... Insertion slot 806 ... Terminal part 807 ... Socket 808 ... Controller 809 ... Operation part A ... First particle B ... Second particle ‥‥ third of particle T1~T6 ‥‥ period

Claims (12)

A display layer including a storage unit that stores first particles that are positively charged and second particles that are negatively charged and have a color complementary to the color of the first particles;
On one surface side of the display layer, a first electrode and a second electrode provided corresponding to the housing portion are provided,
A predetermined voltage is applied between the first electrode and the second electrode, and the first particles and the second particles are mixed with each other and gathered on the one surface side of the display layer. with mixed state, configured to black is the color mixing of the one said color in said housing portion which is visible from the side of the first color and the second particles of the particles of the display layer And
In the mixed state step, a voltage is applied between the first electrode and the second electrode so that the first electrode has a negative potential and the second electrode has a positive potential. A first step of collecting the first particles on one electrode side and collecting the second particles on the second electrode side, and between the first electrode and the second electrode, A voltage at which one electrode has a positive potential and the second electrode has a negative potential is applied to move the first particles to the second electrode side, and the second particles are moved to the first electrode. And a second step of bringing the mixture into the mixed state by being moved to the electrode side . A display layer including a storage unit that stores first particles that are positively charged and second particles that are negatively charged and have a color complementary to the color of the first particles;
On one surface side of the display layer, a first electrode and a second electrode provided corresponding to the housing portion are provided,
A predetermined voltage is applied between the first electrode and the second electrode, and the first particles and the second particles are mixed with each other and gathered on the one surface side of the display layer. with mixed state, configured to black is the color mixing of the one said color in said housing portion which is visible from the side of the first color and the second particles of the particles of the display layer And
In the mixed state step, a voltage is applied between the first electrode and the second electrode so that the first electrode has a negative potential and the second electrode has a positive potential. A first step of collecting the first particles on one electrode side and collecting the second particles on the second electrode side, and applying an alternating voltage between the first electrode and the second electrode. And a second step of bringing the first particles and the second particles into the mixed state by vibrating the first particles and the second particles in a direction away from the first electrode and the second electrode. display device characterized by there. The alternating voltage is greater in the period in which the first electrode is at a negative potential and the second electrode is at the positive potential than in the period in which the first electrode is at a positive potential and the second electrode is at a negative potential. The display device according to claim 2 , wherein The alternating voltage is between a period in which the first electrode is a positive potential and the second electrode is a negative potential, and a period in which the first electrode is a negative potential and the second electrode is a positive potential. The display device according to claim 2 , further comprising a period in which a potential difference is 0 (zero) between the first electrode and the second electrode. Prior to the step of said mixed state, the display device according to any one of claims 1 to 4 wherein the first particles and the second particles in the receptacle is a dispersed state dispersed respectively. On the other surface side of the display layer, it has a first back surface side electrode and a second back surface side electrode provided corresponding to the housing portion,
Applying an alternating voltage between at least one of the first back electrode and the second back electrode and at least one of the first electrode and the second electrode; The display device according to claim 5 , wherein the dispersed state is obtained by vibrating the first particles and the second particles in the thickness direction of the display layer. Between the first back electrode and the second back electrode, and the first electrode and the second electrode, the first back electrode and the second back electrode are positive. Applying a potential, a voltage at which the first electrode and the second electrode have a negative potential, and collecting the first particles on the first electrode and the second electrode side, and the first back surface By collecting the second particles on the side electrode and the second back-side electrode side, the color in the housing portion visually recognized from the one surface side of the display layer is set as the color of the first particle. display device according to any one of claims 1 to 6. The first back side electrode and the second back side electrode are negative between the first back side electrode and the second back side electrode, and the first electrode and the second electrode. Applying a potential, a voltage at which the first electrode and the second electrode are positive potentials, and collecting the second particles on the first electrode and the second electrode side, and the first back surface By collecting the first particles on the side electrode and the second back-side electrode side, the color in the housing portion visually recognized from the one surface side of the display layer is set as the color of the second particles. display device according to any one of claims 1 to 7. The display device according to any one of claims 1 to 8 , wherein the storage unit further stores non-charged white third particles. On the other surface side of the display layer, it has a first back surface side electrode and a second back surface side electrode provided corresponding to the housing portion,
Between the first back-side electrode and the second back-side electrode, and applying the first of the back side electrode negative potential, the voltage which the second back-side electrode has a positive potential, the third By collecting the first particles on the first back surface side electrode side and collecting the second particles on the second back surface side electrode side while dispersing the particles in the container, the display The display device according to claim 9 , wherein a color in the housing portion viewed from the one surface side of the layer is white. One pixel is constituted by at least three of the accommodating portions,
One of the first particles and the second particles accommodated in the first accommodating portion included in the at least three accommodating portions is red, the other is cyan, and the one is accommodated in the second accommodating portion. One of the first particles and the second particles is green, the other is magenta, one of the first particles and the second particles housed in the third housing portion is blue, and the other is yellow The display device according to any one of claims 1 to 10 . An electronic apparatus, comprising the display device according to any one of claims 1 to 11.

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