JP2011227383A - Display unit and electronic device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a display unit with excellent visibility of displayed images without causing a sense of strangeness between a variable display pattern and a fixed display pattern.SOLUTION: A display unit 1 in the present invention comprises: first and second substrates 10 and 11 placed face-to-face at predetermined distance; a plurality of charged particles (black particles and white particles) enclosed in a space between the pair of substrates; first and second electrodes 12 and 13 provided on the pair of substrates; and a fixed display pattern 15 printed on at least one of the pair of substrates. The display unit 1 displays information using: a variable display part for generating an electrical field in the space with the electrodes and for performing display with the variable display pattern which varies depending on which one of the pair of substrates the charged particles are moved to according to the electric field; and a fixed display part for performing stationary display with the fixed display pattern.

Description

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

  In a display device, a constant display area that does not change (hereinafter referred to as a fixed display area) and a display area that includes image changes (hereinafter referred to as a variable display area) are required in one screen. There is a case. For example, when displaying the dial of an analog clock, numbers and scales indicating hours and minutes may be fixed display areas, and hour and minute hands need to be variable display areas. In addition, when the user performs an operation such as pressing a switch on the screen and displays the result according to the operation, the switch part is a fixed display area and the result display part is a variable display area. There is a need. Patent Document 1 below discloses a touch panel device having a configuration in which a fixed display sheet on which predetermined operation keys are drawn is sandwiched between a touch panel and a display device.

Japanese Patent Laid-Open No. 11-312054

  In the touch panel device of Patent Document 1, a liquid crystal display device that performs display using polarization characteristics, a CRT that is a self-luminous element, or the like is used as a display device that configures a variable display region. And the whole information is comprised combining the variable display pattern by a liquid crystal display device or CRT, and the fixed display pattern by printing on a fixed display sheet. However, the fixed display pattern by printing is a display by scattering of external light, and the variable display pattern is a display by light emitted from a liquid crystal display device or a CRT, so that the display is different between the variable display pattern and the fixed display pattern. As a result, there is a problem that the user feels uncomfortable, the display is not settled, and the visibility is lowered.

  The present invention has been made to solve the above-described problems, and provides a display device having excellent visibility of a display image without causing a sense of incongruity between a variable display pattern and a fixed display pattern. Objective. It is another object of the present invention to provide an electronic device including a display portion with excellent visibility.

  In order to achieve the above object, a display device of the present invention includes a pair of substrates opposed to each other at a predetermined interval, a plurality of charged particles enclosed in a space between the pair of substrates, and the pair of substrates. An electrode provided on the substrate and a fixed display pattern printed on at least one of the pair of substrates, and using the electrode to generate an electric field in the space, In response, a variable display unit that displays using a variable display pattern that can be changed depending on which substrate side of the pair of substrates is moved, and a display that does not change depending on the fixed display pattern And a fixed display unit for displaying information.

  According to the display device of the present invention, in the variable display unit, display is performed using a variable display pattern that can be changed depending on which substrate side of the pair of substrates the plurality of charged particles are moved by the electric field. It is carried out. This type of variable display unit is different from display elements having polarization characteristics, such as electroluminescent elements, light emitting diodes, and liquid crystal elements, and displays light by light scattering similar to that of a printed material constituting a fixed display pattern. Therefore, the appearance of the fixed display pattern and the variable display pattern is substantially the same, and a calm display that does not feel uncomfortable for the user is possible, so that an electrophoretic display device with high visibility can be realized. In addition, since it is not necessary to display a fixed display pattern using active pixels, the pixel layout can be simplified and the cost can be reduced.

In the display device according to the aspect of the invention, it is preferable that the fixed display pattern is printed on the space-side surface of the substrate.
In the present specification, the “surface on the space side of the substrate” is referred to as “the inner surface of the substrate”.
According to this configuration, since the fixed display pattern is printed on the inner surface of the substrate, the surface on which the variable display pattern exists and the surface on which the fixed display pattern exist are in a very close state, and parallax does not occur. Therefore, in the case of analog display, for example, when the amount of an arbitrary object is expressed by the length of the bar, the scale of the fixed display pattern is printed on the inner surface of the substrate, so that the length of the bar is accurately determined. Can be read. In addition, by printing the fixed display pattern on the inner surface of the substrate, the appearance of the variable display pattern and the fixed display pattern is made more identical, and it looks as if they are displayed on the same plane, so the texture is close to that of printed paper. Is obtained.

In the display device of the present invention, the fixed display pattern may be made of an insulating material and printed on the electrodes.
According to this configuration, the behavior of the charged particle is different from the other portions only in the portions where the fixed display pattern exists. Depending on the type of charged particles, for example, the display color becomes lighter due to the difference in the electro-optical response characteristics when the voltage application is stopped at the place where the insulating layer of the fixed display pattern exists and the place where it does not exist, It becomes darker. As a result, it is possible to perform a display in which a watermark is inserted in the fixed display pattern, or a display in which the fixed display pattern is emphasized.

In the display device of the present invention, it is preferable that a color difference between the variable display pattern and the fixed display pattern is less than 3.
According to this configuration, the variable display pattern and the fixed display pattern are close to each other, and the color difference is sufficiently small that it is difficult for human eyes to identify. Therefore, it is difficult to understand the boundary between the images displayed by the variable display pattern and the fixed display pattern, and an unbroken image is displayed, thereby improving visibility.

In the display device of the present invention, the fixed display pattern partially overlaps the fixed display pattern printed on the inner surface of the substrate on the surface opposite to the space side of the substrate in the normal direction of the substrate. Furthermore, it is good also as a structure printed.
In the present specification, the “surface opposite to the space side of the substrate” is referred to as “the outer surface of the substrate”.
According to this configuration, since the fixed display pattern on the outer surface side of the substrate and the fixed display pattern on the inner surface side of the substrate appear to be shifted depending on the angle viewed by the user, a stereoscopic effect of the image is generated, and a profound feeling can be expressed. .

In the display device of the present invention, a light absorbing layer having a light absorption rate higher than that of the fixed display pattern may be provided on at least the substrate side of the fixed display pattern printed on the outer surface of the substrate.
According to this configuration, since a part of the light scattered by the charged particles forming the variable display pattern is absorbed by the light absorption layer, the amount of light that irradiates the variable display pattern again decreases, and the periphery of the fixed display pattern Becomes darker. Therefore, the fixed display pattern can be made to appear clearly by setting the viewing side of the printed fixed display pattern to, for example, a bright color tone.

Alternatively, in the display device of the present invention, a light reflection layer having a light reflectance higher than that of the fixed display pattern is provided on at least the substrate side of the fixed display pattern printed on the surface opposite to the space side of the substrate. It is good also as the structure comprised.
According to this configuration, since a part of the light scattered by the charged particles forming the variable display pattern is reflected by the light reflection layer, the amount of light that irradiates the variable display pattern again increases, and the periphery of the fixed display pattern Becomes brighter. Therefore, the fixed display pattern can be emphasized by making the viewing side of the printed fixed display pattern dark, for example.

An electronic apparatus according to the present invention includes the display device according to the present invention.
According to the present invention, by including the display device of the present invention, it is possible to realize an electronic device including a display unit with excellent visibility without causing a sense of incongruity.

It is sectional drawing which shows the electrophoretic display device of 1st Embodiment of this invention. It is sectional drawing which shows the microcapsule which comprises an electrophoretic element. It is a figure for demonstrating operation | movement of an electrophoretic element. It is a figure which shows an example of the display by the variable display part and fixed display part of the electrophoretic display device of this embodiment. It is sectional drawing which shows the electrophoretic display device of 2nd Embodiment of this invention. It is a figure which shows an example of the display by the variable display part and fixed display part of the electrophoretic display device of this embodiment. It is sectional drawing which shows the modification of the electrophoretic display device of this embodiment. It is sectional drawing which shows the electrophoretic display device of 3rd Embodiment of this invention. It is a figure which shows an example of the display by the electrophoretic display device variable display part and fixed display part of this embodiment. It is sectional drawing which shows the electrophoretic display device of 4th Embodiment of this invention. It is a figure which shows an example of the display by the variable display part and fixed display part of the electrophoretic display device of this embodiment. It is sectional drawing which shows the modification of the electrophoretic display device of this embodiment. It is sectional drawing which shows the electrophoretic display device of 5th Embodiment of this invention. It is a figure which shows an example of the display by the variable display part and fixed display part of the electrophoretic display device of this embodiment. It is sectional drawing for demonstrating the effect | action of the electrophoretic display device of this embodiment. It is a figure which shows embodiment of the electronic device of this invention.

[First Embodiment]
Hereinafter, a first embodiment of the present invention will be described with reference to FIGS.
This embodiment is an example in which the display device of the present invention is applied to a segment type electrophoretic display device.
FIG. 1 is a cross-sectional view showing an electrophoretic display device of this embodiment. FIG. 2 is a cross-sectional view of a microcapsule constituting an electrophoretic element. 3A and 3B are diagrams for explaining the operation of the electrophoretic element. 4A to 4C are diagrams showing examples of display by the variable display unit and the fixed display unit of the electrophoretic display device of the present embodiment.
In the following drawings, in order to make each component easy to see, the scale of the size may be varied depending on the component.

In the electrophoretic display device 1 (display device) of the present embodiment, as shown in FIG. 1, a first substrate 10 and a second substrate 11 are arranged to face each other at a predetermined interval, and the first substrate 10 and the second substrate 10 are secondly arranged. An electrophoretic element 32 in which a plurality of microcapsules 20 are arranged in a space between the substrate 11 is disposed. A first electrode 12 and a second electrode 13 for applying a voltage to the electrophoretic element 32 are formed on the inner surface of the first substrate 10 and the inner surface of the second substrate 11, respectively. A fixed display pattern 15 is printed on the outer surface of the second substrate 11.
In addition, a user shall visually recognize a display from the 2nd board | substrate 11 side located in the upper side in FIG.

  The substrate body 71 constituting the first substrate 10 is made of glass, plastic, or the like, and is disposed on the side opposite to the viewing side, and thus may not be a transparent substrate. The first electrode 12 formed on the inner surface of the substrate body 71 is formed of a transparent conductive material such as ITO (indium tin oxide) or a metal material such as aluminum. On the other hand, the substrate body 79 constituting the second substrate 11 is made of glass, plastic, or the like, and is disposed on the viewing side, so that a transparent substrate is used. The second electrode 13 formed on the inner surface of the substrate body 79 is made of a transparent conductive material such as ITO, MgAg (magnesium silver), or IZO (indium / zinc oxide). A voltage is applied to the electrophoretic element 32 by the first electrode 12 and the second electrode 13.

  As shown in FIG. 2, the microcapsule 20 has a particle size of, for example, about 50 μm, and has a dispersion medium 21, a large number of white particles (charged particles) 27, and a large number of black particles (charged particles) inside. 26 is an encapsulated spherical body. The outer shell portion 20a (wall film) of the microcapsule 20 is formed using an acrylic resin such as polymethyl methacrylate or polyethyl methacrylate, a translucent polymer resin such as urea resin, gum arabic, or the like. Yes. The dispersion medium 21 is a liquid that disperses the white particles 27 and the black particles 26 in the microcapsules 20.

  Examples of the dispersion medium 21 include water, alcohol solvents (methanol, ethanol, isopropanol, butanol, octanol, methyl cellosolve, etc.), esters (ethyl acetate, butyl acetate, etc.), ketones (acetone, methyl ethyl ketone, methyl isobutyl ketone, etc.). ), Aliphatic hydrocarbons (pentane, hexane, octane, etc.), alicyclic hydrocarbons (cyclohexane, methylcyclohexane, etc.), aromatic hydrocarbons (benzene, toluene, benzenes having a long-chain alkyl group ( Xylene, hexylbenzene, hebutylbenzene, octylbenzene, nonylbenzene, decylbenzene, undecylbenzene, dodecylbenzene, tridecylbenzene, tetradecylbenzene)), halogenated hydrocarbons (methylene chloride, chloroform, tetrachloride) Element, and 1,2-dichloroethane), can be exemplified a carboxylate, it may be other oils. These substances can be used alone or as a mixture, and a surfactant or the like may be further blended.

  The white particles 27 are particles (polymer or colloid) made of a white pigment such as titanium dioxide, zinc white, and antimony trioxide, and are used, for example, by being negatively charged. The black particles 26 are particles (polymer or colloid) made of a black pigment such as aniline black or carbon black, and are used by being charged positively, for example.

If necessary, these white pigments and black pigments may include electrolytes, surfactants, metal soaps, resins, rubbers, oils, varnishes, compound charge control agents, titanium-based coupling agents, aluminum-based cups. A dispersing agent such as a ring agent and a silane coupling agent, a lubricant, a stabilizer, and the like can be added.
Further, instead of the black particles 26 and the white particles 27, for example, pigments such as red, green, blue, yellow, cyan, magenta and the like may be used. According to such a configuration, red, green, blue, yellow, cyan, magenta, and the like can be displayed on the display unit 5 without using a color filter.
Instead of the above configuration, a one-particle system in which one type of charged particle is dispersed in the colored dispersion medium 21 may be used. Alternatively, a configuration in which two or more kinds of charged particles are dispersed in the colored dispersion medium 21 may be used.
Further, instead of the configuration in which the dispersion medium and particles are enclosed in the microcapsule, a configuration in which the dispersion medium and particles are filled between a pair of substrates may be used. In this case, a partition wall is provided between the pair of substrates. The dispersion medium and the particles may be filled in the cells partitioned by the partition walls.

  When displaying white (W) in the electrophoretic element 32 configured as described above, as shown in FIG. 3A, the second electrode 13 is held at a relatively high potential and the first electrode 12 is relatively moved. Therefore, it is kept at a low potential. That is, when the potential of the second electrode 13 is set to the reference potential, the first electrode 12 is held negative. As a result, an electric field is generated in the space between the first substrate 10 and the second substrate 11, and the white particles 26 negatively charged in accordance with the electric field are attracted to the second electrode 13, while the positively charged black The particles 27 are attracted to the first electrode 12. As a result, white is visually recognized when viewed from the second electrode 13 side.

  On the other hand, when displaying black (B), as shown in FIG. 3B, the second electrode 13 is held at a relatively low potential, and the first electrode 12 is held at a relatively high potential. . That is, when the potential of the second electrode 13 is set as a reference potential, the first electrode 12 is kept positive. As a result, an electric field is generated in the space between the first substrate 10 and the second substrate 11, and the positively charged black particles 27 are attracted toward the second electrode 13 according to the electric field, while being negatively charged. White particles 26 are attracted to the first electrode 12. As a result, when viewed from the second electrode 13 side, black is visually recognized.

The display by the electrophoretic display device 1 having the above configuration will be described with reference to FIG.
Here, the example applied to the display part in the coffee vending machine is assumed.
4A to 4C are diagrams showing an example of display by the electrophoretic display device 1 of the present embodiment, FIG. 4A is a diagram showing a variable display pattern of the variable display unit, and FIG. ) Is a diagram showing a fixed display pattern of the fixed display unit, and FIG. 4C is a diagram showing the entire display information combining the variable display pattern and the fixed display pattern.

  As shown in FIG. 4A, the variable display unit 50 includes five segments 51 arranged in one direction (the vertical direction in FIG. 4A). Each segment 51 is provided with the first electrode 12 and the second electrode 13 described above, and the display can be switched by applying a voltage independently for each segment 51. In the example of the variable display pattern 52 shown in FIG. 4A, the upper three segments 51 are displayed in white, the lower two segments 51 are displayed in black, and the black display portion represents coffee. ing.

  As described above, the fixed display unit 54 includes the fixed display pattern 15 printed on the outer surface of the second substrate 11. As shown in FIG. 4B, the fixed display pattern 15 has a character “currently extracting” and a picture of a cup. The inside of the cup is a transparent portion, and a variable display pattern 52 (portion representing coffee) arranged on the back side as viewed from the user can be visually recognized through the transparent portion.

  Therefore, the entire display information is a combination of the variable display pattern 52 and the fixed display pattern 15 as shown in FIG. In this example, a state in which coffee is being poured into the cup is displayed, and the vending machine is currently extracting coffee and indicates how much the pouring into the cup has progressed.

  If the variable display pattern is formed by a self-luminous display element such as an electroluminescence element or a light emitting diode, or a display element having a polarization characteristic such as a liquid crystal element, the fixed display pattern formed by printing is bright when the external light is strong. While it can be clearly seen, the variable display pattern is difficult to see, so there is a sense of incongruity and the display is inferior in visibility. In contrast, in the case of the electrophoretic display device 1 of the present embodiment, the variable display pattern 52 is an image formed by the electrophoretic element 32. For this reason, the variable display pattern 52 is displayed by scattering of external light as in the print body constituting the fixed display pattern 15, so that the fixed display pattern 15 and the variable display pattern 52 can be seen regardless of the intensity of external light. It becomes almost the same. Therefore, it is possible to provide a calm display that does not feel uncomfortable for the user, and an electrophoretic display device with high visibility can be realized. Further, since there is no need to display the fixed display pattern 52 with active pixels, the pixel layout can be simplified and the cost can be reduced.

[Second Embodiment]
Hereinafter, a second embodiment of the present invention will be described with reference to FIGS.
This embodiment is an example in which the display device of the present invention is applied to an active matrix electrophoretic display device.
FIG. 5 is a cross-sectional view showing the electrophoretic display device of this embodiment. 6A to 6C are diagrams showing examples of display by the variable display unit and the fixed display unit of the electrophoretic display device of the present embodiment. FIG. 7 is a cross-sectional view showing a modification of the electrophoretic display device of this embodiment. 5 and 7, the same reference numerals are given to the same components as those in FIG. 1 used in the first embodiment, and detailed description thereof will be omitted.

  As shown in FIG. 5, the electrophoretic display device 100 of the present embodiment is sandwiched between an element substrate 30 (first substrate), a counter substrate 31 (second substrate), and the element substrate 30 and the counter substrate 31. The electrophoretic element 32 is provided. On the surface of the element substrate 30 on which the electrophoretic element 32 is disposed, a scanning line 36, a data line 38, a selection transistor 41, and the like are formed.

  A semiconductor layer 72 is formed on the inner surface of the substrate body 71 constituting the element substrate 30, and a gate insulating film 73 is formed so as to cover the semiconductor layer 72. The semiconductor layer 72 includes, for example, non-single-crystal silicon materials such as amorphous silicon and polycrystalline silicon, oxide semiconductor materials, transparent oxide semiconductor materials such as In—Ga—Zn—O, and organic substances such as fluorene-bithiophene copolymers. A semiconductor material or the like can be used. When an oxide semiconductor material is used for the semiconductor layer 72, an oxide insulating material is preferably used for the gate insulating film 73. When an organic semiconductor material is used for the semiconductor layer 72, the gate insulating film 73 is used. It is also desirable to use an organic insulating material.

  On the gate insulating film 73, the scanning line 36 that functions as the gate electrode of the selection transistor 41 is formed. For the scanning line 36, for example, a metal laminated film of an Al—Nd alloy and Mo can be used. In addition, Al alone, ITO, Cu, Cr, Ta, Mo, Nb, Ag, Pt, Pd, In, Nd, and alloys thereof can be used. A first interlayer insulating film 74 is formed on the entire surface of the substrate body 71 so as to cover the scanning lines 36. For the first interlayer insulating film 74, for example, an inorganic insulating material such as a silicon nitride film, a silicon oxide film, or a silicon nitride oxide film, or an organic insulating material can be used. A data line 38 electrically connected to the source region of the semiconductor layer 72 through the contact hole 75 is formed on the first interlayer insulating film 74. The same material as that of the scanning line 36 can be used for the data line 38.

  A second interlayer insulating film 76 is formed on the entire surface of the first interlayer insulating film 74 so as to cover the data line 38. As the first interlayer insulating film 74, for example, an inorganic insulating material such as a silicon nitride film, a silicon oxide film, or a silicon nitride oxide film, or an organic insulating material can be used for the second interlayer insulating film 76. A pixel electrode 35 electrically connected to the drain region of the semiconductor layer 72 through the contact hole 77 is formed on the second interlayer insulating film 76. The pixel electrode 35 is made of, for example, a transparent conductive material such as ITO (indium tin oxide) or a metal material such as Al. A voltage corresponding to each pixel is applied to each pixel electrode 35 via a selection transistor, and a voltage is applied to the electrophoretic element 32 between the counter electrode 37.

  On the other hand, a counter electrode 37 is formed on the inner surface of the substrate body 79 constituting the counter substrate 31. A common voltage is applied to the counter electrode 37, and a voltage is applied to the electrophoretic element 32 together with the pixel electrode 35. The counter electrode 37 is made of a transparent conductive material such as MgAg (magnesium silver), ITO, or IZO (indium / zinc oxide). Further, a fixed display pattern 16 constituting a fixed display portion is printed on the counter electrode 37. When ink having conductivity is used when printing the fixed display pattern 16, the electrophoretic element 32 operates in the same manner as when the fixed display pattern 16 is not provided.

The display by the electrophoretic display device 100 having the above configuration will be described with reference to FIG.
Here, an example applied to an analog timepiece having an hour hand and a minute hand is assumed.
6A to 6C are diagrams illustrating an example of display by the electrophoretic display device 100 according to the present embodiment. FIG. 6A is a diagram illustrating a configuration of a variable display unit, and FIG. FIG. 6C is a diagram showing the fixed display pattern of the fixed display unit, and FIG. 6C is a diagram showing the entire display information combining the variable display pattern and the fixed display pattern.

  As shown in FIG. 6A, the variable display unit 56 includes a plurality of pixels 40 arranged in a matrix in two directions orthogonal to each other (the vertical direction and the horizontal direction in FIG. 6A). . Each pixel 40 is provided with the above-described pixel electrode 35, and is configured to be switched between black display and white display for each pixel 40 by applying a voltage between the counter electrode 37. Here, the variable display 56 displays the minute hand and hour hand that move over time.

  As described above, the fixed display unit 57 is composed of the fixed display pattern 16 printed on the counter electrode 37 on the inner surface side of the counter substrate 31. As shown in FIG. 6B, the fixed display pattern 16 has numbers “3”, “6”, “9”, “12” and scales. The inside of the scale printed in an annular shape is a transparent portion, and the variable display pattern 58 (minute hand and hour hand) arranged on the back side as viewed from the user can be visually recognized through the transparent portion.

  Therefore, the entire display information is a combination of the variable display pattern 58 and the fixed display pattern 16 as shown in FIG. In this example, a predetermined time by an analog clock is displayed by a combination of the variable display pattern 58 and the fixed display pattern 16.

  Also in the electrophoretic display device 100 of the present embodiment, an uncomfortable and calm display is possible, an electrophoretic display device with high visibility can be realized, the pixel layout can be simplified, and the cost can be reduced. The same effect as in the first embodiment can be obtained.

  In particular, in the case of the present embodiment, since the fixed display pattern 16 is printed on the inner surface side of the counter substrate 31, the surface on which the variable display pattern 58 exists and the surface on which the fixed display pattern 16 exist are in a very close state. No parallax occurs. Therefore, in addition to the analog timepiece of this embodiment, when performing an analog display such as expressing the amount of an arbitrary object with the length of a bar, the time and numerical value can be set by printing the scale on the inner surface of the substrate. It becomes possible to read accurately. For example, in a conventional analog voltmeter or the like, in order to avoid reading errors due to parallax, it was solved by attaching a mirror to the scale part, but by providing the display unit of this embodiment, a simulated analog voltmeter without parallax Can be provided. In this way, by printing the fixed display pattern 16 on the inner surface of the counter substrate 31, the appearances of the variable display pattern 58 and the fixed display pattern 16 are further made identical, and appear to be displayed on the same plane, A thin texture similar to a printed matter on paper can be obtained.

  Further, instead of the above configuration, as shown in FIG. 7, the fixed display pattern 16 is printed on the inner surface of the substrate body 79 of the counter substrate 31, and the counter electrode 37 is formed on the fixed display pattern 16. Also good. Even when this configuration is adopted, display without parallax can be performed as in the configuration of FIG.

In the present embodiment, it is desirable that the color difference between the display color of the variable display pattern 58 by the electrophoretic element 32 and the display color of the fixed display pattern 16 by printing is less than 3.
In the CIE L * a * b * color space, the color difference ΔE may be calculated by calculating the square root (distance between two coordinates) of the sum of the differences of the L * axis, a * axis, and b * axis. That is,
ΔE = √ (ΔL ^{* 2} + Δa ^{* 2} + Δb ^{* 2} )
It is.

  According to this configuration, the display positions of the variable display pattern 58 and the fixed display pattern 16 are sufficiently matched, and the color difference between the two patterns is sufficiently small that it is difficult for human eyes to identify. Therefore, it is difficult to understand the boundary between the images displayed by the variable display pattern 58 and the fixed display pattern 16, and an unbroken image is displayed, thereby improving visibility.

  For example, when the electrophoretic display device 100 of the present embodiment is applied to a signboard or the like that displays either “business” or “closed” characters, the “business” portion is set as a fixed display pattern, and “business” is displayed. Even if only the “rest” portion is set as the variable display pattern, the observer does not feel uncomfortable. Similarly, when the electrophoretic display device 100 of the present embodiment is applied to a signboard or the like that displays any of the characters “open” and “closed”, the gate portions of the characters “open” and “close” and “ The “shop” portion may be a fixed display pattern and the remaining portion may be a variable display pattern. Alternatively, when displaying not only characters but also arrow symbols “→” and “←”, the “−” portion is a fixed display pattern, and the “>” and “<” portions are variable display patterns. do it.

  As described above, by combining the electrophoretic element 32 having light scattering properties and the printing in which light scattering occurs on the inner surface of the counter substrate 32, the variable display by the electrophoretic element 32 and the fixed display by printing are integrated. Visible. Thereby, the pixel structure of the variable display part 56 can be simplified and the power consumption required for display can be reduced.

[Third Embodiment]
Hereinafter, a third embodiment of the present invention will be described with reference to FIGS.
This embodiment is an example in which the display device of the present invention is applied to an active matrix electrophoretic display device.
FIG. 8 is a cross-sectional view showing the electrophoretic display device of this embodiment. FIGS. 9A to 9C are diagrams showing examples of display by the variable display unit and the fixed display unit of the electrophoretic display device of this embodiment.
In FIG. 8, the same components as those in FIG. 5 used in the second embodiment are denoted by the same reference numerals, and detailed description thereof is omitted.

  In the electrophoretic display device 110 of the present embodiment, as shown in FIG. 8, the counter electrode 37 is formed on the inner surface of the substrate body 79 of the counter substrate 31, and the fixed display pattern 17 constituting the fixed display unit on the counter electrode 37. Is printed. This laminated structure is the same as in the second embodiment. In the second embodiment, the material of the ink for printing the fixed display pattern is not particularly limited, but in the present embodiment, an insulating material is used as the ink for printing the fixed display pattern 17. In the case of forming on the counter substrate 31 (the substrate on the viewing side) as in the present embodiment, the fixed display pattern 17 is formed using a transparent or translucent light-transmitting material. However, the fixed display pattern 17 only needs to be light transmissive, and need not be colorless. Further, when the fixed display pattern 17 is formed on the element substrate 30 (substrate opposite to the viewing side), it is not necessary to have light transmittance.

The display by the electrophoretic display device 110 having the above configuration will be described with reference to FIG.
Here, the example applied to the electronic paper mainly used for the use which displays a sentence is assumed.
9A to 9C are diagrams showing an example of display by the electrophoretic display device 110 of the present embodiment, FIG. 9A is a diagram showing the configuration of the variable display unit, and FIG. FIG. 9C is a diagram showing the fixed display pattern of the fixed display unit, and FIG. 9C is a diagram showing the entire display information in which the variable display pattern and the fixed display pattern are combined.

  As shown in FIG. 9A, the variable display section 60 is composed of a plurality of pixels 40 arranged in a matrix in two directions orthogonal to each other (the vertical direction and the horizontal direction in FIG. 9A). . Each pixel 40 is provided with a pixel electrode 35, and is configured to be switched between black display and white display for each pixel 40 by applying a voltage to the counter electrode 37. Here, the character portion is displayed by the variable display section 60.

  As described above, the fixed display unit 61 is configured by the fixed display pattern 17 made of an insulating material printed on the counter electrode 37 on the inner surface side of the counter substrate 31. As shown in FIG. 9B, the fixed display pattern 17 has ruled lines extending in the horizontal direction of FIG. 9B. The part between the ruled lines is a transparent part, and the variable display pattern 62 (characters) arranged on the back side as viewed from the user can be visually recognized through the transparent part.

  Therefore, the entire display information is a combination of the variable display pattern 62 and the fixed display pattern 17 as shown in FIG. 9C. In this example, a sentence in which each line is separated by a ruled line is displayed by a combination of the variable display pattern 62 and the fixed display pattern 17.

  Also in the electrophoretic display device 110 of the present embodiment, an uncomfortable and calm display is possible, an electrophoretic display device with high visibility can be realized, the pixel layout can be simplified, and the cost can be reduced. The same effects as those of the first and second embodiments can be obtained.

  In particular, in the case of the present embodiment, the behavior of the charged particles is different from other portions only at the portions where the fixed display pattern 17 exists. Depending on the type of charged particles, for example, the display color of the fixed display pattern 17 is different due to the difference in electro-optical response characteristics when the voltage application is stopped between the place where the insulating layer of the fixed display pattern 17 is present and the place where the insulating layer is not present. Becomes thinner or darker. As a result, it is possible to perform display such that the fixed display pattern 17 is watermarked or the fixed display pattern is emphasized. In the example of FIGS. 9A to 9C, for example, when the ruled line is printed in dark black, after all the pixels 40 of the variable display section 60 are once displayed in black and then switched to white display, fixed display is performed. The color of the ruled line of the pattern 17 changes to light black. Therefore, when information such as characters is displayed in black, the color of the ruled line can be made inconspicuous with respect to the color of the characters, and the readability of the information is improved.

[Fourth Embodiment]
Hereinafter, a fourth embodiment of the present invention will be described with reference to FIGS.
This embodiment is an example in which the display device of the present invention is applied to an active matrix electrophoretic display device.
FIG. 10 is a cross-sectional view showing the electrophoretic display device of this embodiment. FIGS. 11A to 11C are diagrams showing examples of display by the variable display unit and the fixed display unit of the electrophoretic display device of the present embodiment. FIG. 12 is a cross-sectional view showing a modification of the electrophoretic display device of this embodiment.
10-12, the same code | symbol is attached | subjected to the same component as FIGS. 5-7 used by 2nd Embodiment, and detailed description is abbreviate | omitted.

  In the electrophoretic display device 120 of the present embodiment, as shown in FIG. 10, the counter electrode 37 is formed on the inner surface of the substrate body 79 of the counter substrate 31, and the first fixed that constitutes the fixed display unit on the counter electrode 37. A display pattern 16 is printed. Further, the second fixed display pattern 18 constituting the fixed display unit is also printed on the outer surface of the substrate body 79 of the counter substrate 31. As in the second embodiment, when the conductive ink is used when printing the first fixed display pattern 16, the electrophoretic element 32 operates in the same manner as when the first fixed display pattern 16 is not provided. On the other hand, the second fixed display pattern 18 hardly affects the operation of the electrophoretic element 32 regardless of the type of ink.

The display by the electrophoretic display device 120 having the above configuration will be described with reference to FIG.
Here, as in the second embodiment, an example applied to an analog timepiece having an hour hand and a minute hand is assumed.
FIGS. 11A to 11C are diagrams showing an example of display by the electrophoretic display device 120 of the present embodiment, FIG. 11A is a diagram showing the configuration of the variable display unit, and FIG. FIG. 11C shows a fixed display pattern of the fixed display unit, and FIG. 11C shows the entire display information in which the variable display pattern and the fixed display pattern are combined.

  As shown in FIG. 11A, the variable display unit 62 includes a plurality of pixels 40 arranged in a matrix in two directions orthogonal to each other (the vertical direction and the horizontal direction in FIG. 11A). . Each pixel 40 is provided with a pixel electrode 35, and is configured to be switched between black display and white display for each pixel 40 by applying a voltage between the counter electrode 37. Here, the variable hand 62 displays the minute hand and hour hand that move over time.

  As described above, the fixed display unit 63 includes the first fixed display pattern 16 printed on the counter electrode 37 on the inner surface side of the counter substrate 31 and the second fixed display printed on the outer surface side of the counter substrate 31. Pattern 18. The first fixed display pattern 16 and the second fixed display pattern 18 are the same, and are printed at substantially overlapping positions when viewed from the substrate normal direction. As shown in FIG. 11B, the first fixed display pattern 16 and the second fixed display pattern 18 have numbers “3”, “6”, “9”, “12” and scales. ing. The inside of the scale printed in an annular shape is a transparent portion, and the variable display pattern 64 (minute hand and hour hand) arranged on the back side as viewed from the user can be visually recognized through the transparent portion.

  Therefore, the entire display information is a combination of the variable display pattern 64 and the fixed display patterns 16 and 18 as shown in FIG. 11C. In this example, a predetermined time by an analog clock is displayed by a combination of the variable display pattern 64 and the fixed display patterns 16 and 18.

  Also in the electrophoretic display device 120 of the present embodiment, an uncomfortable and calm display is possible, an electrophoretic display device with high visibility can be realized, the pixel layout can be simplified, and the cost can be reduced. The same effects as those of the first to third embodiments can be obtained.

  Particularly in the case of this embodiment, the first fixed display pattern 16 and the second fixed display pattern 18 are provided on the inner surface side and the outer surface side of the counter substrate 31 having a predetermined plate thickness, respectively. For this reason, the first fixed display pattern 16 and the second fixed display pattern 18 appear to be shifted depending on the angle viewed by the user, so that the stereoscopic effect of the image is generated as shown in FIG. can do. Even if the first fixed display pattern 16 and the second fixed display pattern 18 are printed at a position where they are completely overlapped when viewed from the normal direction of the substrate, the first fixed display pattern 16 and the second fixed display pattern 18 appear to be shifted depending on the angle viewed by the user. It suffices that at least a portion overlaps, and printing may be performed at a position slightly shifted from the beginning.

  Further, instead of the above configuration, as shown in FIG. 12, the first fixed display pattern 16 is printed on the inner surface of the substrate body 79 of the counter substrate 31, and the counter electrode 37 is formed on the first fixed display pattern 16. It is good also as the structure currently formed. Even when this configuration is adopted, an image with a three-dimensional effect can be displayed as in the configuration of FIG.

[Fifth Embodiment]
Hereinafter, a fifth embodiment of the present invention will be described with reference to FIGS.
This embodiment is an example in which the display device of the present invention is applied to an active matrix electrophoretic display device.
FIG. 13 is a cross-sectional view showing the electrophoretic display device of this embodiment. 14A to 14C are diagrams showing examples of display by the variable display unit and the fixed display unit of the electrophoretic display device of the present embodiment. FIG. 15 is a diagram for explaining the operation of the electrophoretic display device of this embodiment.
13-15, the same code | symbol is attached | subjected to the same component as FIGS. 5-7 used in 2nd Embodiment, and detailed description is abbreviate | omitted.

  In the electrophoretic display device 140 of this embodiment, as shown in FIG. 13, the counter electrode 37 is formed on the inner surface of the substrate body 79 of the counter substrate 31, and the fixed display pattern 18 is printed on the outer surface of the substrate body 79. . Further, a light absorption layer 19 having a light absorption rate higher than that of the fixed display pattern 18 is printed on the substrate main body 79 side of the fixed display pattern 18. In the case of the present embodiment, the fixed display pattern 18 is preferably printed with a light color ink such as white or light blue, and the light absorption layer 19 has a light absorption rate higher than that of the fixed display pattern, for example, dark such as black. Printing with colored inks is preferred.

The display by the electrophoretic display device 140 having the above configuration will be described with reference to FIG.
Here, as in the second embodiment, an example applied to an analog timepiece having an hour hand and a minute hand is assumed.
14A to 14C are diagrams showing an example of display by the electrophoretic display device 140 of the present embodiment, FIG. 14A is a diagram showing the configuration of the variable display unit, and FIG. FIG. 14C is a diagram showing a fixed display pattern of the fixed display unit, and FIG. 14C is a diagram showing the entire display information in which the variable display pattern and the fixed display pattern are combined.

  As shown in FIG. 14A, the variable display unit 56 includes a plurality of pixels 40 arranged in a matrix in two directions orthogonal to each other (the vertical direction and the horizontal direction in FIG. 14A). . Each pixel 40 is provided with a pixel electrode 35, and is configured to be switched between black display and white display for each pixel 40 by applying a voltage between the counter electrode 37. Here, the variable display 56 displays the minute hand and hour hand that move over time.

  As described above, the fixed display unit 65 includes the light absorption layer 19 and the fixed display pattern 18 that are sequentially printed on the outer surface side of the counter substrate 31. The fixed display pattern 18 and the light absorption layer 19 are formed so as to overlap each other when viewed from the substrate normal direction. As shown in FIG. 14B, “3”, “6”, “9”, “12 ”And a scale. The inside of the scale printed in an annular shape is a transparent portion, and the variable display pattern 58 (minute hand and hour hand) arranged on the back side as viewed from the user can be visually recognized through the transparent portion.

  Therefore, the entire display information is a combination of the variable display pattern 58 and the fixed display pattern 18 as shown in FIG. In this example, a predetermined time by an analog clock is displayed by a combination of the variable display pattern 58 and the fixed display pattern 18.

  Also in the electrophoretic display device 140 of the present embodiment, an uncomfortable and calm display is possible, an electrophoretic display device with high visibility can be realized, the pixel layout can be simplified, and the cost can be reduced. The same effects as those of the first to fourth embodiments can be obtained.

  In particular, in the case of this embodiment, since the light absorption layer 19 is provided between the substrate body 79 of the counter substrate 31 and the fixed display pattern 18, a variable display pattern 58 is formed as shown in FIG. A part of the light scattered on the surface of the electrophoretic element 32 is absorbed by the light absorption layer 19. For this reason, in the region close to the fixed display pattern 18, the amount of light irradiated again with the variable display pattern 58 is reduced, and the peripheral region of the fixed display pattern 18 is slightly darker than the region away from the fixed display pattern 18. Therefore, the fixed display pattern 18 printed in a bright color such as white or light blue appears to be clearly lifted, and visibility can be improved.

  Instead of the above configuration, a configuration in which a light reflecting layer having a light reflectance higher than that of the fixed display pattern 18 is printed on the substrate main body 79 side of the fixed display pattern 18 may be adopted. In that case, it is preferable to print the fixed display pattern 18 with dark ink such as black, and the light reflection layer has a light reflectance higher than that of the fixed display pattern 18, for example, light ink such as white. It is preferable to print.

  According to this configuration, since a part of the light scattered on the surface of the electrophoretic element 32 forming the variable display pattern 58 is reflected by the light reflection layer, the amount of light that irradiates the variable display pattern 58 again increases. The peripheral area of the fixed display pattern 18 becomes slightly brighter than the area away from the fixed display pattern 18. Therefore, the fixed display pattern 18 printed in a dark color such as black appears to be more emphasized, and visibility can be improved.

  The technical scope of the present invention is not limited to the above embodiment, and various modifications can be made without departing from the spirit of the present invention. For example, in the above embodiment, only the example in which the fixed display pattern is printed on the substrate on the viewing side is given, but the fixed display pattern is printed on the substrate on the opposite side to the viewing side, although the visibility of the fixed display pattern is slightly inferior. May be.

  Further, the specific configuration such as the material, shape, number, and the like of each constituent member of the electrophoretic display device is not limited to the above embodiment, and can be changed as appropriate. In addition, an example of an electrophoretic element has been given as a display element constituting a variable display unit. In addition, an electropowder fluid (charged particle) made of charged polymer polymer particles is applied to either the front plate side or the back plate side by an electric field. It is also possible to employ an electronic powder fluid type display element that performs display by moving it.

[Electronics]
Next, a case where the electrophoretic display device 100 of the above embodiment is applied to an electronic device will be described.
FIG. 16A is a perspective view illustrating a configuration of the electronic paper 1100. An electronic paper 1100 includes the electrophoretic display device of the above embodiment in a display area 1101. The electronic paper 1100 is flexible and includes a main body 1102 made of a rewritable sheet having the same texture and flexibility as conventional paper.

  FIG. 16B is a perspective view showing the configuration of the electronic notebook 1200. An electronic notebook 1200 is obtained by bundling a plurality of the electronic papers 1100 and sandwiching them between covers 1201. The cover 1201 includes display data input means (not shown) for inputting display data sent from an external device, for example. Thereby, according to the display data, the display content can be changed or updated while the electronic paper is bundled.

According to the electronic paper 1100 and the electronic notebook 1200 described above, since the electrophoretic display device according to the present invention is employed, it is possible to realize an electronic apparatus including a display unit with low cost and excellent visibility.
In addition, said electronic device illustrates the electronic device which concerns on this invention, Comprising: The technical scope of this invention is not limited. For example, the display device according to the present invention can be suitably used for a display unit of an electronic device such as a watch, a mobile phone, and a portable audio device.

  DESCRIPTION OF SYMBOLS 10 ... 1st board | substrate, 11 ... 2nd board | substrate, 12 ... 1st electrode, 13 ... 2nd electrode, 15, 16, 17, 18 ... Fixed display pattern, 19 ... Light absorption layer, 26 ... Black particle (charged particle) 27 ... white particles (charged particles), 30 ... element substrate (first substrate), 31 ... counter substrate (second substrate), 32 ... electrophoretic element, 35 ... pixel electrode, 37 ... counter electrode, 50, 56, 60, 62 ... variable display unit, 52, 58, 64 ... variable display pattern, 54, 57, 63 ... fixed display unit, 1, 100, 110, 120, 130, 140 ... electrophoretic display device (display device), 1100 ... electronic paper (electronic equipment), 1200 ... electronic notebook (electronic equipment).

Claims (8)

A pair of substrates opposed to each other at a predetermined interval;
A plurality of charged particles enclosed in a space between the pair of substrates;
Electrodes provided on the pair of substrates;
A fixed display pattern printed on at least one of the pair of substrates,
An electric field is generated in the space using the electrode, and a variable display pattern that can be changed depending on which substrate side of the pair of substrates is moved according to the electric field is used. A display device that displays information using a variable display unit that performs display and a fixed display unit that performs display that does not vary depending on the fixed display pattern.   The display device according to claim 1, wherein the fixed display pattern is printed on a surface of the substrate on the space side.   The display device according to claim 2, wherein the fixed display pattern is made of an insulating material and printed on the electrode.   The display device according to claim 2, wherein a color difference between the variable display pattern and the fixed display pattern is less than 3. 5.   The fixed display pattern is further printed on the surface of the substrate opposite to the space side so as to partially overlap the fixed display pattern printed on the space side surface in the normal direction of the substrate. The display device according to claim 2, wherein the display device is a display device.   The light absorption layer having a light absorption rate higher than that of the fixed display pattern is provided on at least the substrate side of the fixed display pattern printed on the surface opposite to the space side of the substrate. 5. The display device according to 5.   The light reflection layer having a light reflectance higher than that of the fixed display pattern is provided on at least the substrate side of the fixed display pattern printed on the surface opposite to the space side of the substrate. 5. The display device according to 5.   An electronic apparatus comprising the display device according to claim 1.

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