WO2012137779A1 - Display element, manufacturing method, and electrical apparatus - Google Patents

Abstract

Provided is a display element (2) which is configured to be capable of changing a display color on a display surface by moving a polarized fluid (12). An effective display part (ED), having a plurality of pixel regions (P), and an ineffective display part (ND), which is disposed to surround the effective display part (ED), are set. The polarized fluid (12) and an oil (insulating fluid) (13) are sealed within the pixel regions (P). Furthermore, a dummy pixel region (dummy region) (DP) is disposed between an upper substrate (6) and a lower substrate (7) corresponding to the ineffective display part (ND), and the polarized fluid (12) and the oil (13) are sealed within the dummy pixel region (DP).

Description

Display element, manufacturing method, and electric apparatus

The present invention relates to a display element that displays information such as images and characters by moving a polar liquid, a method of manufacturing the display element, and an electrical apparatus using the display element.

Recently, as represented by electrowetting type display elements, display elements that display information using the phenomenon of movement of a conductive liquid by an external electric field have been developed and put into practical use.

Specifically, in the conventional display element as described above, for example, as described in Patent Document 1 below, a plurality of first and second substrates and a plurality of interiors of a space formed between these substrates are provided. A first fluid sealed for each pixel region and a second fluid incompatible with the first fluid are provided. In this conventional display element, by applying an electric field to the first fluid, the first fluid is moved to change the display color on the display surface side.

Further, in this conventional display element, the step of disposing the first and second fluids on the first substrate, the step of disposing the sealing agent on the first substrate, and above the sealing agent and the first substrate. By placing a second substrate, bonding the first and second substrates together to form a space surrounded by the first and second substrates, and curing the sealant, The display element has been manufactured.

International Publication No. 2009/065909 Pamphlet

However, in the conventional display element as described above, the first and / or second fluid (polar liquid and / or insulating fluid) is sealed in the pixel region arranged in the outer peripheral portion of the display surface of the display element. In some cases, a part of the first and / or second fluid thus evaporated may evaporate before the first and second substrates are bonded to each other. Thereby, in this conventional display element, the liquid amount of the first and / or second fluid is non-uniform in a plurality of pixel regions on the display surface, and a bright spot is generated in a part of the pixel region. In some cases, gradation display is not properly performed in a part of the pixel region. As a result, the conventional display element has a problem that the display quality is deteriorated.

In view of the above-described problems, an object of the present invention is to provide a display element that can prevent deterioration in display quality, a method for manufacturing the display element, and an electric device using the display element.

In order to achieve the above object, the display element according to the present invention is configured such that a predetermined display space is formed between the first substrate provided on the display surface side and the first substrate. , The second substrate provided on the non-display surface side of the first substrate, the effective display area and the non-effective display area set with respect to the display space, and at least the inside of the display space A display element configured to be capable of changing a display color on the display surface side by moving the polar liquid, the polar liquid encapsulated movably on the effective display area side,
A first electrode installed in the display space so as to be in contact with the polar liquid; and the first and second electrodes in a state of being electrically insulated from the polar liquid and the first electrode. A second electrode provided on one side of the second substrate;
An effective display unit having a plurality of pixel regions provided so as to divide the display space by ribs and an ineffective display unit provided to surround the effective display unit are set on the display surface. And
Encapsulating the polar liquid and an insulating fluid that does not mix with the polar liquid inside each of the plurality of pixel regions in the effective display unit,
A dummy region is provided between the first and second substrates corresponding to the ineffective display portion, and a predetermined liquid is sealed in the dummy region.

In the display element configured as described above, the effective display portion and a non-effective display portion provided so as to surround the effective display portion are set on the display surface. Further, a polar liquid and an insulating fluid are sealed inside each of the plurality of pixel regions in the effective display portion. Further, a dummy region is provided between the first and second substrates corresponding to the ineffective display portion, and a predetermined liquid is sealed inside the dummy region. Thereby, it is possible to prevent a part of the polar liquid and the insulating fluid enclosed in each of the plurality of pixel regions in the effective display portion from evaporating. As a result, unlike the conventional example, it is possible to configure a display element that can prevent deterioration in display quality.

In the display element, it is preferable that the polar liquid and the insulating fluid are used as the predetermined liquid.

In this case, the number of parts of the display element can be reduced, and a low-cost display element can be easily configured.

Further, in the display element, it is preferable that the ineffective display portion is set by a light shielding film provided on at least one side of the first and second substrates.

In this case, the non-effective display portion can be reliably set by the light shielding film, and the deterioration of the display quality can be surely prevented.

In the display element, the dummy area may be partitioned by a rib in a shape different from that of the pixel area.

In this case, the size of the ineffective display portion can be easily reduced as compared with the case where the dummy area is divided in the same shape as the pixel area.

In the display element, data wiring and gate wiring are provided in a matrix on one side of the first and second substrates.
On the other side of the first and second substrates, a planar transparent electrode as the first electrode is provided,
Each of the plurality of pixel regions is provided in an intersection unit between the data line and the gate line,
In each of the plurality of pixel regions, a switching element connected to the data wiring and the gate wiring, a pixel electrode as the second electrode connected to the switching element, and a charge supplied to the pixel electrode A capacitor for holding may be provided.

In this case, a matrix drive type display element having excellent display quality can be formed.

In the display element, it is preferable that a dielectric layer provided on one side of the first and second substrates is used as the capacitor so as to cover the pixel electrode.

In this case, it is possible to omit the installation of a capacitor composed of discrete components, and a display device having a simple structure can be easily configured.

Further, in the display element, a signal electrode installed inside the display space is used as the first electrode.
As the second electrode, a reference electrode provided on one side of the first and second substrates so as to be installed on one side of the effective display area and the non-effective display area, and the effective display area Scanning electrode provided on one side of the first and second substrates in a state of being electrically insulated from the reference electrode so as to be installed on the other side of the side and the ineffective display area side May be used.

In this case, the display color on the display surface side can be changed without providing a switching element, and a display element with a simple structure can be configured.

In the display element, the plurality of signal electrodes are provided along a predetermined arrangement direction,
The plurality of reference electrodes and the plurality of scanning electrodes are provided alternately with each other and intersect with the plurality of signal electrodes,
A signal voltage applying unit that is connected to the plurality of signal electrodes and applies a signal voltage within a predetermined voltage range to each of the plurality of signal electrodes in accordance with information displayed on the display surface side; ,
A selection voltage that is connected to the plurality of reference electrodes and that allows the polar liquid to move within the display space in response to the signal voltage for each of the plurality of reference electrodes; A reference voltage applying unit for applying one of a non-selection voltage for preventing the polar liquid from moving inside the display space;
A selection voltage that is connected to the plurality of scan electrodes and that allows the polar liquid to move within the display space in response to the signal voltage for each of the plurality of scan electrodes; It is preferable to include a scanning voltage application unit that applies one voltage of a non-selection voltage that prevents the polar liquid from moving inside the display space.

In this case, a matrix drive type display element having excellent display quality can be easily configured.

In the display element, it is preferable that each of the plurality of pixel regions is provided in a unit of intersection of the signal electrode and the scanning electrode.

In this case, the display color on the display surface side can be changed in units of pixels by moving the polar liquid in each of the plurality of pixels on the display surface side.

In the display element, it is preferable that a dielectric layer is laminated on the surfaces of the reference electrode and the scanning electrode.

In this case, the electric field applied to the polar liquid by the dielectric layer can be reliably increased, and the moving speed of the polar liquid can be improved more easily.

In the display element, the plurality of pixel regions may be provided in accordance with a plurality of colors capable of full color display on the display surface side.

In this case, a color image can be displayed by appropriately moving the corresponding polar liquid in each of the plurality of pixels.

In the display element, the ineffective display area is set by a light shielding film provided on one side of the first and second substrates,
The effective display area is preferably set by an opening formed in the light shielding film.

In this case, it is possible to appropriately and reliably set the effective display area and the non-effective display area for the display space.

In the display element, it is preferable that the non-effective display portion and the non-effective display area are set by the same light shielding film provided on the first substrate side.

In this case, a display element having a simple structure can be easily configured.

The electrical device of the present invention is an electrical device including a display unit that displays information including characters and images,
Any one of the display elements described above is used for the display portion.

In the electric device configured as described above, since a display element capable of preventing a reduction in display quality is used in the display unit, an electric device having excellent display performance can be easily configured.

In addition, in the method for manufacturing a display element of the present invention, the first substrate is formed so that a predetermined display space is formed between the first substrate provided on the display surface side and the first substrate. The second substrate provided on the non-display surface side of the substrate, the effective display region and the non-effective display region set with respect to the display space, and at least the effective display region side in the display space A display element configured to change a display color on the display surface side by moving the polar liquid, the polar liquid encapsulated in a movable manner,
By setting a rib on one side of the first and second substrates, a plurality of pixel areas are set in the effective display area, and a dummy area is set in the ineffective display area surrounding the effective display area. Process,
Encapsulating at least one of the polar liquid and an insulating fluid that does not mix with the polar liquid in each of the plurality of pixel regions and enclosing a predetermined liquid in the dummy region And a process.

In the method of manufacturing the display element configured as described above, the polar liquid and the insulating fluid sealed in each of the plurality of pixel regions in the effective display unit are sequentially performed by performing the region setting step and the sealing step. At least one part can be prevented from evaporating. As a result, unlike the conventional example, it is possible to configure a display element that can prevent deterioration in display quality.

In the display element manufacturing method, the sealing step includes a first sealing step of sealing the predetermined liquid into the dummy region;
It is preferable that after the first sealing step, a second sealing step of sealing at least one of the polar liquid and the insulating fluid is included in the inside of each of the plurality of pixel regions. .

In this case, since the predetermined liquid is sealed in the dummy area in the non-effective display area before the internal area in the effective display area, the multiple pixel areas in the effective display area. It is possible to more reliably prevent a part of at least one of the polar liquid and the insulating fluid sealed in the inside of the liquid from evaporating. As a result, unlike the conventional example, it is possible to more easily configure a display element that can prevent deterioration in display quality.

In the method for manufacturing the display element, it is preferable that the polar liquid and the insulating fluid are used as the predetermined liquid.

In this case, the number of parts of the display element can be reduced, and a low-cost display element can be easily configured.

According to the present invention, it is possible to provide a display element that can prevent display quality from deteriorating, a method for manufacturing the display element, and an electric device using the display element.

FIG. 1 is a plan view for explaining a display element and an image display apparatus according to a first embodiment of the present invention. FIG. 2 is a diagram illustrating a specific configuration of a main part in the pixel region of the display element shown in FIG. FIG. 3 is a plan view showing an effective display portion and an ineffective display portion on the display surface of the display element shown in FIG. FIG. 4 is a diagram for explaining the pixel area in the effective display section and the dummy pixel area in the non-effective display section shown in FIG. FIG. 5 is an enlarged plan view showing a main configuration of the upper substrate side in the effective display section shown in FIG. 3 when viewed from the display surface side. FIG. 6 is an enlarged plan view showing a main configuration of the lower substrate side in the effective display section shown in FIG. 3 when viewed from the non-display surface side. FIG. 7 is an enlarged plan view showing a main configuration of the upper substrate side in the ineffective display portion shown in FIG. 3 when viewed from the display surface side. FIG. 8 is an enlarged plan view showing a main configuration of the lower substrate side in the non-effective display portion shown in FIG. 3 when viewed from the non-display surface side. FIG. 9A and FIG. 9B are cross-sectional views showing the main configuration of the display element shown in FIG. 1 during non-CF color display and CF color display, respectively. FIG. 10A to FIG. 10C are diagrams for explaining the formation process on the upper substrate side shown in FIG. FIG. 11A to FIG. 11E are diagrams for explaining the formation process on the lower substrate side shown in FIG. FIG. 12 is a view for explaining the oil filling process in the dummy pixel region in the ineffective display section shown in FIG. FIG. 13 is a diagram for explaining a process of enclosing oil in the pixel area in the effective display section shown in FIG. FIG. 14A is a diagram illustrating a process of bonding the upper substrate and the lower substrate, and FIG. 14B is a diagram illustrating a final manufacturing process of the display element. FIG. 15 is a plan view for explaining a display element and an image display apparatus according to the second embodiment of the present invention. 16 is a plan view showing an effective display portion and an ineffective display portion on the display surface of the display element shown in FIG. FIG. 17 is a diagram illustrating the pixel area in the effective display section and the dummy pixel area in the non-effective display section shown in FIG. FIG. 18 is an enlarged plan view showing a main configuration of the upper substrate side in the effective display section shown in FIG. 16 when viewed from the display surface side. FIG. 19 is an enlarged plan view showing a main configuration of the lower substrate side in the effective display section shown in FIG. 16 when viewed from the non-display surface side. FIG. 20 is an enlarged plan view showing a main configuration of the upper substrate side in the ineffective display portion shown in FIG. 16 when viewed from the display surface side. FIG. 21 is an enlarged plan view showing a main configuration of the lower substrate side in the non-effective display portion shown in FIG. 16 when viewed from the non-display surface side. 22 (a) and 22 (b) are cross-sectional views showing the main configuration of the display element shown in FIG. 15 during CF color display and non-CF color display, respectively. FIG. 23A to FIG. 23D are diagrams for explaining the formation process on the upper substrate side shown in FIG. 24 (a) to 24 (e) are diagrams for explaining the formation process on the lower substrate side shown in FIG. FIG. 25 is a diagram illustrating a process of enclosing polar liquid in the dummy pixel region in the ineffective display section shown in FIG. FIG. 26 is a diagram for explaining a process of enclosing the polar liquid into the pixel region in the effective display section shown in FIG. FIG. 27A is a diagram illustrating a process of bonding the upper substrate and the lower substrate illustrated in FIG. 22, and FIG. 27B illustrates a final manufacturing process of the display element illustrated in FIG. 15. It is a figure to do. FIG. 28 is a diagram for explaining an operation example of the image display apparatus shown in FIG. FIG. 29 is a plan view showing a pixel region in the effective display portion and a dummy region in the ineffective display portion of the display element according to the third embodiment of the present invention.

Hereinafter, a preferred embodiment showing a display element, a manufacturing method, and an electric device of the present invention will be described with reference to the drawings. In the following description, a case where the present invention is applied to an image display device including a display unit capable of displaying information will be described as an example. Moreover, the dimension of the structural member in each figure does not faithfully represent the actual dimension of the structural member, the dimensional ratio of each structural member, or the like.

[First Embodiment]
FIG. 1 is a plan view for explaining a display element and an image display apparatus according to a first embodiment of the present invention. In FIG. 1, the image display device 1 of the present embodiment is provided with a display unit using the display element 2 of the present embodiment, and a rectangular display surface is configured in the display unit. In the image display device 1, as will be described in detail later, an effective display unit that displays information and an ineffective display unit that does not display information are set on the display surface.

Further, the display element 2 is provided with a display control unit 3, and a source driver 4 and a gate driver 5 connected to the display control unit 3. A video signal is input to the display control unit 3 from the outside, and the display control unit 3 creates each instruction signal to the source driver 4 and the gate driver 5 based on the input video signal. And output. Thereby, the display element 2 displays information including characters and images according to the video signal.

In addition, the display element 2 includes an upper substrate 6 and a lower substrate 7 that are arranged so as to overlap each other in a direction perpendicular to the paper surface of FIG. 1, and the upper substrate 6 and the lower substrate 7 overlap each other. An effective display area on the display surface is formed (details will be described later).

Further, in the display element 2, a plurality of source lines S as data lines are provided in stripes along the X direction at a predetermined interval from each other. In the display element 2, the plurality of gate lines G are provided in stripes along the Y direction at predetermined intervals. The source lines S and the gate lines G are provided in a matrix so as to intersect with each other on the lower substrate 6, for example. In the display element 2, the source lines S and the gate lines G are in units of intersections. A plurality of pixel areas are set.

The plurality of source lines S and the plurality of gate lines G are connected to the source driver 4 and the gate driver 5, respectively, and each source line S and each gate line G are input to the display control unit 3. A source signal (voltage signal) and a gate signal corresponding to the video signal are supplied from the source driver 4 and the gate driver 5, respectively.

Furthermore, in the display element 2, as will be described in detail later, each of the plurality of pixel regions is partitioned by a partition wall. In the display element 2, for each of a plurality of pixels (display cells) provided in a matrix, a polar liquid described later is deformed (moved) by the electrowetting phenomenon, and the display color on the display surface side is changed. It is like that.

Here, the pixel structure of the display element 2 will be described in detail with reference to FIGS.

FIG. 2 is a diagram for explaining a specific configuration of the main part in the pixel region of the display element shown in FIG. FIG. 3 is a plan view showing an effective display portion and an ineffective display portion on the display surface of the display element shown in FIG. FIG. 4 is a diagram for explaining the pixel area in the effective display section and the dummy pixel area in the non-effective display section shown in FIG. FIG. 5 is an enlarged plan view showing a main configuration of the upper substrate side in the effective display section shown in FIG. 3 when viewed from the display surface side. FIG. 6 is an enlarged plan view showing a main configuration of the lower substrate side in the effective display section shown in FIG. 3 when viewed from the non-display surface side. FIG. 7 is an enlarged plan view showing a main configuration of the upper substrate side in the ineffective display portion shown in FIG. 3 when viewed from the display surface side. FIG. 8 is an enlarged plan view showing a main configuration of the lower substrate side in the non-effective display portion shown in FIG. 3 when viewed from the non-display surface side. FIG. 9A and FIG. 9B are cross-sectional views showing the main configuration of the display element shown in FIG. 1 during non-CF color display and CF color display, respectively. In FIG. 6, the source wiring S and the gate wiring G are not shown for simplification of the drawing.

As shown in FIG. 2, in the display element 2, each of the plurality of pixel regions is set in a unit of intersection of the source line S and the gate line G, and a thin film transistor (switching element) ( TFT) SW, a pixel electrode 8 as a second electrode, and a capacitor C are provided. That is, in the display element 2, in each pixel region, the source electrode and the gate electrode of the thin film transistor SW are connected to the source line S and the gate line G, respectively. Further, the drain electrode of the thin film transistor SW is connected to the pixel electrode 8, and the pixel electrode 8 is constituted by a capacitor C formed by a dielectric layer 14 described later provided on the lower substrate 7 side so as to cover the pixel electrode 8. It is connected to the. In each pixel region, when the thin film transistor SW is turned on by the gate signal, a voltage corresponding to the video signal is supplied as a source signal to the pixel electrode 8 via the source wiring S and the thin film transistor SW, The electric charge according to the voltage is held by the capacitor C (dielectric layer 14). As described above, the display element 2 constitutes the above-described display portion of the active matrix driving method having a switching element (active element) for each pixel.

In the display element 2, as described above, an effective display portion and an ineffective display portion are set on the display surface. Specifically, as shown in FIG. 3, in the display element 2, an effective display portion ED that closes a large area of the rectangular display surface including the center of the display surface, and the effective display portion ED are surrounded. The ineffective display portion ND provided as described above is set. The effective display portion ED includes a plurality of the pixel regions P (FIG. 4) provided to divide the display space K (FIG. 9) by the ribs 11 (FIG. 4). On the other hand, the ineffective display portion ND includes a plurality of dummy pixel regions DP (FIG. 4) as dummy regions.

Further, in the display element 2, the size of the dummy region (the total size of the plurality of dummy pixel regions DP) is the polar liquid 12 enclosed in the plurality of pixel regions P and oil as an insulating fluid. It is determined based on the amount of 13 encapsulated.

More specifically, when the display element 2 forms a 3 × 1 RGB specification display panel with QVGA (Quarter Video Graphics Graphics Array), for example, in the X direction of the effective display unit ED (for example, the horizontal direction of the display panel). The number of pixel regions P (number of pixels) is 320 pixels, and the number (pixel number) of pixel regions P in the Y direction (for example, the vertical direction of the display panel) of the effective display portion ED is 240 × 3 (RGB). Pixel. The number (number of pixels) of dummy pixel regions DP in the X direction of the ineffective display portion ND is 5 pixels in each of the left and right portions of the effective display portion ED, and the dummy pixels in the Y direction of the ineffective display portion ND. The number of the regions DP (number of pixels) is 5 pixels in each of the upper part and the lower part of the effective display portion ED.

More specifically, in the upper right part of the display element 2, as shown in FIG. 4, the pixel area P included in the effective display part ED is provided in six pixels in the X direction and the Y direction, respectively. Further, dummy pixel regions DP included in the non-effective display portion ND of 5 pixels are provided in the X direction and the Y direction so as to surround these 36 pixel regions P. Further, the pixel region P and the dummy pixel region DP are divided into the same shape by the ribs 11 as the partition walls. In addition, color filter portions (openings) 10r, 10g, and 10b of any color are formed in each pixel region P of the effective display portion ED. On the other hand, the opening is not formed in each dummy pixel region DP of the non-effective display portion ND, and is shielded from light by a black matrix portion 10s described later as a light shielding film.

Further, the polar liquid 12 and the oil 13 are sealed in each pixel area P of the effective display portion ED, and the polar liquid 12 and the oil 13 as a predetermined liquid are filled in each dummy pixel area DP of the non-effective display portion ND. It is enclosed. However, as illustrated in FIG. 4, in the dummy pixel region DP, particularly in the dummy pixel region DP close to the outermost peripheral portion, a part of the oil 13 evaporates during the manufacturing process of the display element 2, and the amount of liquid is changed to each pixel. It is less than the appropriate amount of oil 13 in the region P.

2 to 9, the display element 2 includes the upper substrate 6 as the first substrate provided on the display surface side, and the first substrate provided on the back side (non-display surface side) of the upper substrate 2. And the lower substrate 7 as a second substrate. In the display element 2, the upper substrate 6 and the lower substrate 7 are arranged at a predetermined distance from each other, so that a predetermined display space K is formed between the upper substrate 6 and the lower substrate 7. . However, the display space K functions in the effective display portion ED, and does not function in the ineffective display portion ND. Further, as described above, in the display space K, the polar liquid 12 and the insulating colored oil 13 that does not mix with the polar liquid 12 are placed in the X direction in the display space K. The polar liquid 12 is movably enclosed, and can move from an ineffective display area P2 side described later to an effective display area P1 side.

As the polar liquid 12, for example, a mixed liquid of ethylene glycol and water is used. The polar liquid 12 is a colorless and transparent liquid. However, the polar liquid 12 may be mixed with a water-soluble liquid such as a lower alcohol in order to adjust its density, viscosity, melting point and boiling point, and is colored red, green, blue, or the like. Therefore, a self-dispersing pigment or a water-soluble dye may be mixed.

Further, as the oil 13, for example, a mixture of alkane oil and toluene colored in black with, for example, a pigment or a dye is used. In addition to this description, as the oil 13, for example, a non-polar solvent composed of one or more selected from side chain higher alcohol, side chain higher fatty acid, alkane hydrocarbon, silicone oil, and matching oil, for example, pigment Alternatively, those colored with dyes may be used. The oil 13 moves inside the display space K as the polar liquid 12 slides.

Further, the oil 13 is filled into the inside of each pixel region P and the inside of each dummy pixel region DP by being filled on the lower substrate 7 by, for example, a dispenser method or an ink jet method.

Furthermore, since the oil 13 is colored in black, the oil 13 functions as a shutter that allows or blocks light transmission in each pixel. That is, in each pixel of the display element 2, as will be described later in detail, the oil 13 modulates the area where the oil 13 is located in the effective display area P1 inside the display space K, whereby the display is in the light absorption state and the light transmission state. And can be switched.

For the upper substrate 6, a transparent glass material such as a non-alkali glass substrate or a transparent transparent sheet material such as a transparent synthetic resin such as an acrylic resin is used. Further, the color filter layer 10 and the common electrode 9 as the first electrode are sequentially formed on the surface of the upper substrate 6 on the non-display surface side. However, as illustrated in FIG. 5, the common electrode 9 is provided on the non-display surface side of the upper substrate 6 corresponding to the pixel region P included in the effective display portion ED (on the surface of the color filter layer 10). 7, as illustrated in FIG. 7, the non-display surface side surface side (on the surface of the color filter layer 10) of the upper substrate 6 corresponding to the dummy pixel region DP included in the ineffective display portion ND. ) Is not formed.

The lower substrate 7 is made of a transparent glass material such as a transparent glass material such as a non-alkali glass substrate or a transparent synthetic resin such as an acrylic resin, like the upper substrate 6. The pixel electrode 8 and the thin film transistor SW are provided on the surface of the lower substrate 7 on the display surface side. Further, the dielectric layer 14 is formed so as to cover the pixel electrode 8 and the thin film transistor SW. Is formed. However, the pixel electrode 8 and the thin film transistor SW are formed only on the display surface side surface of the lower substrate 7 corresponding to the pixel region P included in the effective display portion ED, as illustrated in FIG. As illustrated in FIG. 8, it is not formed on the display surface side surface of the lower substrate 7 corresponding to the dummy pixel region DP included in the ineffective display portion ND.

Further, the source line S is provided on the display surface side surface of the lower substrate 7 only in the portion of the effective display portion ED and the portion of the non-effective display portion ND between the source driver 4 and the effective display portion ED. Is provided. Similarly, the gate wiring G is provided on the surface of the lower substrate 7 on the display surface side only in the portion of the effective display portion ED and the portion of the ineffective display portion ND between the gate driver 5 and the effective display portion ED. Is provided.

The dielectric layer 14 is formed on the surface on the display surface side of the lower substrate 7 corresponding to each of the pixel region P included in the effective display portion ED and the dummy pixel region DP included in the ineffective display portion ND. ing. Further, a rib 11 having a first rib member 11a and a second rib member 11b provided so as to be parallel to the X direction and the Y direction is provided on the surface of the dielectric layer 14 on the display surface side. It has been. Further, the lower substrate 7 is provided with a water repellent film 15 so as to cover the dielectric layer 14 and the ribs 11. In addition to the above description, the thin film transistor SW may not be covered by the dielectric layer 14.

Further, on the back side (non-display surface side) of the lower substrate 7, for example, a backlight 16 that emits white illumination light is integrally assembled, and the transmissive display element 2 is configured. The backlight 16 uses a light source such as a cold cathode fluorescent tube or an LED.

The pixel electrode 8 is a transparent electrode made of a transparent electrode material such as ITO. The pixel electrode 8 is provided on the lower substrate 7 so as to be installed below the effective display area P1. The thin film transistor SW is provided on the lower substrate 7 so as to be installed below the ineffective display area P2.

As the common electrode 9, a transparent electrode made of a transparent electrode material such as ITO is used in the same manner as the pixel electrode 8. The common electrode 9 is a flat transparent electrode, and the common electrode 9 covers all the pixel regions P provided on the display surface.

The color filter layer 10 is provided with red (R), green (G), and blue (B) color filter portions 10r, 10g, and 10b, and a black matrix portion 10s as a light shielding film. The pixels of each color of RGB are configured. That is, in the color filter layer 10, as illustrated in FIG. 5, RGB color filter portions 10 r, 10 g, and 10 b are sequentially provided along the Y direction, and three color filter portions 10 r, 10 g, and 10 b are each provided with X A total of nine pixels are arranged in the X direction and the Y direction, respectively.

In the display element 2, as illustrated in FIG. 5, in each pixel region P, any one of RGB color filter portions 10 r, 10 g, and 10 b is provided at a location corresponding to the effective display region P 1 of the pixel, A black matrix portion 10s is provided at a location corresponding to the ineffective display area P2. That is, in the display element 2, an ineffective display region P2 (non-opening portion) is set by the black matrix portion (light-shielding film) 10s with respect to the display space K, and the opening portion (non-opening portion) formed in the black matrix portion 10s ( That is, the effective display area P1 is set by any one of the color filter portions 10r, 10g, and 10b).

In the display element 2, the area of the color filter portions 10r, 10g, and 10b is selected to be the same or slightly smaller than the area of the effective display area P1. On the other hand, the area of the black matrix portion 10s is selected to be the same or slightly larger than the area of the ineffective display area P2. In FIG. 5, in order to clarify the boundary portion between adjacent pixels, the boundary line between two black matrix portions 10 s corresponding to the adjacent pixels is indicated by a dotted line. Then, there is no boundary line between the black matrix portions 10s.

Further, in the display element 2, the display space K is divided into pixel unit P units by the ribs 11 as the partition walls. That is, in the display element 2, the display space K of each pixel has two first rib members 11a having appropriate heights facing each other and appropriate heights facing each other, as illustrated in FIG. It is divided by two second rib members 11b. Furthermore, in the display element 2, the first and second rib members 11a and 11b prevent the polar liquid 12 from easily flowing into the display space K of the adjacent pixel region P. That is, for example, negative-type photocurable resin is used for the first and second rib members 11a and 11b, and the first and second rib members 11a and 11b are light transmissive. Further, in these first and second rib members 11a and 11b, the protruding height from the dielectric layer 14 is determined so that the polar liquid 12 is prevented from flowing in and out between adjacent pixels.

In addition to the above description, for example, the first and second rib members 11a and 11b may be separated from each other so that gaps are generated at the four corners of the pixel region P, for example. Further, the end portions of the ribs 11 configured in the frame shape may be brought into close contact with the upper substrate 2 side so that the adjacent pixel regions P are hermetically separated.

In the display element 2, as illustrated in FIG. 7, only the black matrix portion 10s provided on the non-display surface side surface of the upper substrate 6 is provided in each dummy pixel region DP of the ineffective display portion ND. ing. That is, the ineffective display portion ND is set by a light shielding film provided on the upper substrate (first substrate) 6 side. In FIG. 7, in order to clarify the boundary portion between adjacent dummy pixels, the boundary line between the two black matrix portions 10s corresponding to the adjacent dummy pixels is indicated by a dotted line. In the portion 10s, there is no boundary line between the black matrix portions 10s.

Further, as illustrated in FIG. 8, in the non-effective display portion ND, the display space K is divided into dummy pixel regions DP by the ribs 11 as in the effective display portion ED. On the other hand, in the ineffective display portion ND, unlike the effective display portion ED, the pixel electrode 8 and the thin film transistor SW are not provided.

The dielectric layer 14 is made of a transparent dielectric film containing, for example, silicon nitride, hafnium oxide, titanium dioxide, or barium titanate. The water repellent film 15 is made of a transparent synthetic resin, preferably, for example, a fluorine-based resin that becomes a hydrophilic layer with respect to the polar liquid 12 when a voltage is applied. Thereby, in the display element 2, the wettability (contact angle) with the polar liquid 12 on the surface side of the lower substrate 7 on the display space K side can be greatly changed, and the polar liquid 12 moves (deforms). ) The speed can be increased.

In each pixel region P of the display element 2 configured as described above, as illustrated in FIG. 9A, when the oil 13 is held below the color filter portion 11r, light from the backlight 16 is emitted. The oil 13 is shielded from light and a black display (non-CF color display) is performed. On the other hand, as illustrated in FIG. 9B, when the oil 13 is held below the black matrix portion 10s, the light from the backlight 16 passes through the color filter portion 10r without being blocked by the oil 13. Thus, red display (CF color display) is performed by the light of the backlight 16.

Here, with reference to FIGS. 10 to 14, the manufacturing process of the display element 2 of the present embodiment will be specifically described.

FIG. 10A to FIG. 10C are diagrams for explaining the formation process on the upper substrate side shown in FIG. FIG. 11A to FIG. 11E are diagrams for explaining the formation process on the lower substrate side shown in FIG. FIG. 12 is a view for explaining the oil filling process in the dummy pixel region in the ineffective display section shown in FIG. FIG. 13 is a diagram for explaining a process of enclosing oil in the pixel area in the effective display section shown in FIG. FIG. 14A is a diagram illustrating a process of bonding the upper substrate and the lower substrate, and FIG. 14B is a diagram illustrating a final manufacturing process of the display element.

In FIG. 10A, an alkali-free glass substrate having a thickness of 0.7 mm, for example, is used for the upper substrate 6, and the color filter portions 10r, 10g, 10b and the black matrix portion are formed by using, for example, a photolithography method. By laminating 10 s on the surface of the upper substrate 6, the CF forming step is performed, and the color filter layer 10 is formed. The color filter layer 10 uses a photosensitive resin (for example, photoreactive acrylic monomer) and a corresponding pigment, and has a thickness of about 2 μm, for example. Further, the color filter portions 10r, 10g, and 10b are formed only on the effective display portion ED (FIG. 3) and not formed on the non-effective display portion ND (FIG. 3). That is, as shown in FIG. 10B, only the black matrix portion 10s is formed on the surface of the upper substrate 6 in the ineffective display portion ND.

Thereafter, as shown in FIG. 10C, an electrode forming step of the common electrode 9 is performed in the effective display portion ED. That is, in this electrode formation step, the common electrode 9 is formed by forming an ITO film having a thickness of 100 nm on the color filter layer 10 by sputtering, for example.

Further, in FIG. 11A, a non-alkali glass substrate having a thickness of 0.7 mm, for example, is used for the lower substrate 7, and the formation process of the pixel electrode 8 and the thin film transistor SW is performed in the effective display portion ED. . That is, in this formation step, the pixel electrode 8 is formed by forming an ITO film having a thickness of 100 nm on the surface of the lower substrate 7 by, for example, sputtering. On the surface of the lower substrate 7, a thin film transistor SW made of TFT is formed by a known manufacturing process.

Next, as shown in FIG. 11B, a dielectric layer 14 forming step is performed. That is, a silicon nitride film was formed as the dielectric layer 14 on the pixel electrode 8 and the thin film transistor SW by using, for example, a CVD method. The film thickness of the dielectric layer 14 is, for example, 350 nm. In the non-effective display portion ND, as shown in FIG. 11C, the pixel electrode 8 and the thin film transistor SW are not formed, and only the dielectric layer 14 is formed on the surface of the lower substrate 7.

Subsequently, as shown in FIG. 11D, an installation step of providing the rib 11 on the dielectric layer 14 is performed. That is, in this installation step, the first and second rib members 11a and 11b using photo-curing resin are formed on the surface of the dielectric layer 14 in the pixel region P unit and the dummy pixel region DP unit. The Further, by performing this installation process, a plurality of pixel areas P are set in the effective display area ED, and a dummy pixel area (dummy area) DP is set in the ineffective display area ND surrounding the effective display area ED. The area setting process is completed.

Next, as shown in FIG. 11 (e), a forming step of forming a water repellent film 15 on the surface of the dielectric layer 14 and the first and second rib members 11a and 11b is performed. That is, in this forming step, for example, a fluorine-based resin material is applied to the surface of the dielectric layer 14 and the first and second rib members 11a and 11b by dipping and baked at 80 ° C. for 30 minutes. Thus, the water repellent film 15 is formed.

Subsequently, an oil 13 filling step is performed on the lower substrate 6. In this encapsulating step, first, the dummy pixel region DP of the ineffective display portion ND is performed, and then the pixel region P of the effective display portion ED is performed.

That is, as shown in FIG. 12, a first sealing step for sealing oil 13 as a predetermined liquid is performed on each dummy pixel region DP of the ineffective display portion ND by, for example, a dispenser method or an inkjet method. Is called.

Subsequently, as shown in FIG. 13, a second enclosing step of enclosing the oil 13 is performed on each pixel region P of the effective display portion ED by, for example, a dispenser method or an inkjet method.

Next, as shown in FIG. 14A, the upper substrate 6 is assembled to the lower substrate 7 holding the oil 13 from above, and the upper substrate 6 and the lower substrate 7 are bonded together.

Thereafter, in FIG. 14B, a step of enclosing the polar liquid 12 using the capillary phenomenon from the gap between the pixel areas P and the gap between the dummy pixel areas DP is performed. Then, the display element 10 is completed by installing the backlight 16 on the lower substrate 7 side.

Here, the display operation of the image display device 1 of the present embodiment configured as described above will be specifically described.

In FIG. 1, the display control unit 3 sequentially outputs gate signals for turning on the thin film transistors SW from the gate driver 5 to the gate wiring G in a predetermined scanning direction from the upper side to the lower side in FIG. . When the thin film transistor SW is turned on, the display control unit 3 causes the source driver 4 to output a source signal (voltage signal) corresponding to the video signal to the corresponding source line S. As a result, in the corresponding pixel, the voltage from the source line S is applied to the pixel electrode 8, and charges are accumulated in the capacitor C (dielectric layer 14). The accumulated electric charge is maintained in the capacitor C for a period of one frame until the gate line G is next selected.

Further, in the display element 2, when the black display shown in FIG. 9A is performed, the source signal is sent from the source driver 4 to the source wiring so that the potential difference between the pixel electrode 8 and the common electrode 9 becomes 0V. It is output to the pixel electrode 8 via S. When such a voltage application is applied to the pixel electrode 8, the polar liquid 12 in the pixel region P is colored by an oil 13 having a relatively high affinity with the water-repellent film as shown in FIG. It will be in the state located below the filter part 10r, and will be in the state which covered the said color filter part 10r completely. As a result, in the display element 2, the light from the backlight 16 is blocked by the oil 13 and black display is performed.

Further, in the display element 2, when the red display shown in FIG. 9B is performed, the source difference is set so that the potential difference between the pixel electrode 8 and the common electrode 9 becomes a predetermined voltage value (for example, 16V). A signal is output from the source driver 4 to the pixel electrode 8 via the source line S. When such voltage application is applied to the pixel electrode 8, charges are accumulated on the surface of the water repellent film 15 and the hydrophilicity is increased. Therefore, the polar liquid 12 in the pixel region P is shown in FIG. As shown, it is held in a state of being located below the color filter portion 10r side. As a result, in the display element 2, the light from the backlight 16 is not blocked by the oil 13, but is allowed to be emitted to the viewer side such as a user, and a red display is performed. Further, in the image display device 1, when the oil 13 moves to the ineffective display area P <b> 2 side in all three adjacent RGB pixels and CF colored display is performed, Red light, green light, and blue light are mixed with white light, and white display is performed.

In the display element 2, the source signal is sent from the source driver 4 through the source line S so that the potential difference between the pixel electrode 8 and the common electrode 9 becomes a voltage value between 0 V and the predetermined voltage value. When the output is made to the pixel electrode 8, halftone display according to the voltage value can be performed. That is, according to the voltage applied to the pixel electrode 8, the oil 13 moves to the lower side of the color filter portion 10r, so that the shielding ratio by the oil 13 with respect to the color filter portion 10r changes, and the observer side By changing the amount of light emitted from the emitted backlight 16, halftone display can be performed.

In the display element 2 of the present embodiment configured as described above, the effective display portion ED and the ineffective display portion ND provided so as to surround the effective display portion ED are set on the display surface. . In addition, a polar liquid 12 and oil (insulating fluid) 13 are sealed inside each of the plurality of pixel regions P in the effective display portion ED. Further, a dummy pixel region (dummy region) DP is provided between the upper substrate 6 and the lower substrate 7 corresponding to the ineffective display portion ND, and the polar liquid 12 and the oil 13 are provided inside the dummy pixel region DP. Is enclosed. As a result, in the present embodiment, it is possible to prevent a part of the polar liquid 12 and the oil 13 enclosed in each of the plurality of pixel regions P in the effective display unit ED from evaporating. As a result, in the present embodiment, unlike the conventional example, it is possible to configure the display element 2 that can prevent the display quality from being deteriorated.

In the present embodiment, the ineffective display portion ND is set by the black matrix portion (light shielding film) 10s provided on the upper substrate (first substrate) 6 side. Therefore, it is possible to reliably prevent the display quality from deteriorating.

In this embodiment, the size of the dummy pixel region DP is determined based on the amount of the polar liquid 12 and the oil 13 enclosed in each of the plurality of pixel regions P. Accordingly, in the present embodiment, the polar liquid 12 and the oil 13 can be appropriately sealed inside the dummy pixel region DP, and a part of the polar liquid 12 and the oil 13 can be more reliably prevented from being evaporated. Can do.

Moreover, in this embodiment, as shown in FIG.12 and FIG.13, after performing the 1st enclosure process, the 2nd enclosure process is performed. As a result, in the present embodiment, oil (predetermined liquid) is first applied to the inside of the dummy pixel region DP in the non-effective display portion ND rather than the inside of each of the plurality of pixel regions P in the effective display portion ED. Since 13 is enclosed, it is possible to more reliably prevent a part of the oil 13 enclosed in each of the plurality of pixel regions P in the effective display portion ED from evaporating. As a result, in the present embodiment, unlike the conventional example, the display element 2 that can prevent the display quality from being deteriorated can be configured more easily.

In the present embodiment, the non-effective display area P2 is set by the black matrix portion (light shielding film) 10s provided on the upper substrate 6, and the effective display area P1 is set by the color filter portions (openings) 10r, 10g, and 10b. Since it is set, the effective display area P1 and the ineffective display area P2 can be appropriately and reliably set for the display space K.

Further, in the display element 2 of the present embodiment, the source wiring (data wiring) S and the gate wiring G are provided in a matrix on the lower substrate 7, and the planar common electrode (transparent electrode) 9 is provided on the upper substrate 6. It has been. Further, in the display element 2 of the present embodiment, each of the plurality of pixel regions P is provided in units of intersections of the source wiring S and the gate wiring G, and in each pixel region P, the display space K is a rib (partition). Wall) 11. Furthermore, in the display element 2 of the present embodiment, each pixel region P is provided with a thin film transistor (switching element) SW, a pixel electrode (second electrode) 8, and a dielectric layer (capacitor) 14. Thereby, in the present embodiment, it is possible to configure the matrix drive type display element 2 having an excellent display quality.

Further, in the image display device (electric device) 1 of the present embodiment, the display element 2 that can prevent the display quality from being deteriorated is used in the display unit. Therefore, the image display device 1 having excellent display performance is provided. It can be easily configured.

In addition to the above description, a reflection electrode may be used as the pixel electrode 8. In such a configuration, the installation of the backlight 16 can be omitted, and a display element with low power consumption can be easily configured.

[Second Embodiment]
FIG. 15 is a plan view for explaining a display element and an image display apparatus according to the second embodiment of the present invention. In the figure, the main difference between this embodiment and the first embodiment is that a signal electrode as a first electrode and a reference electrode and a scan electrode as a second electrode are used. In addition, about the element which is common in the said 1st Embodiment, the same code | symbol is attached | subjected and the duplicate description is abbreviate | omitted.

That is, as shown in FIG. 15, in the image display apparatus 1 of the present embodiment, a display unit using the display element 2 ′ of the present embodiment is provided, and a rectangular display surface is configured on the display unit. Has been. Further, in the display element 2 ′ of the present embodiment, an effective display area of the display surface is formed by an overlapping portion of the upper substrate 6 and the lower substrate 7 as in the first embodiment (details are given) (See below.)

In the display element 2 ′, a plurality of signal electrodes 18 are provided in stripes along the X direction at a predetermined interval from each other. In the display element 2 ′, a plurality of reference electrodes 19 and a plurality of scanning electrodes 20 are provided alternately in a stripe pattern along the Y direction. The plurality of signal electrodes 18, the plurality of reference electrodes 19, and the plurality of scanning electrodes 20 are provided so as to intersect with each other. In the display element 2 ′, the unit of intersection between the signal electrode 18 and the scanning electrode 20 is provided. In addition, a plurality of pixel areas are set.

The plurality of signal electrodes 18, the plurality of reference electrodes 19, and the plurality of scanning electrodes 20 are independently of each other a high voltage (hereinafter referred to as “H voltage”) as a first voltage and a second voltage. A voltage within a predetermined voltage range between the low voltage and the low voltage (hereinafter referred to as “L voltage”) can be applied (details will be described later).

Further, in the display element 2 ′, as described in detail later, each of the plurality of pixel regions is partitioned by a partition wall. In the display element 2 ′, a polar liquid 12 ′ described later is moved by an electrowetting phenomenon for each of a plurality of pixels (display cells) provided in a matrix to change the display color on the display surface side. It is like that.

Further, each of the plurality of signal electrodes 18, the plurality of reference electrodes 19, and the plurality of scanning electrodes 20 has one end portion drawn out of the effective display area of the display surface to form terminal portions 18 a, 19 a, and 20 a. ing.

A signal driver 21 is connected to each terminal portion 18a of the plurality of signal electrodes 18 via a wiring 21a. The signal driver 21 constitutes a signal voltage application unit. When the image display device 1 displays information including characters and images on the display surface, the signal driver 21 responds to the information for each of the plurality of signal electrodes 18. The signal voltage Vd is applied.

Further, a reference driver 22 is connected to each terminal portion 19a of the plurality of reference electrodes 19 via a wiring 22a. The reference driver 22 constitutes a reference voltage application unit. When the image display device 1 displays information including characters and images on the display surface, the reference driver 22 applies a reference voltage Vr to each of the plurality of reference electrodes 19. Is applied.

Further, a scanning driver 23 is connected to each terminal portion 20a of the plurality of scanning electrodes 20 via a wiring 23a. The scanning driver 23 constitutes a scanning voltage application unit. When the image display device 1 displays information including characters and images on the display surface, the scanning voltage Vs is applied to each of the plurality of scanning electrodes 20. Is applied.

In the scan driver 23, a non-selection voltage that prevents the polar liquid from moving with respect to each of the plurality of scan electrodes 20, and a selection voltage that allows the polar liquid to move according to the signal voltage Vd. One of the voltages is applied as the scanning voltage Vs. The reference driver 22 is configured to operate with reference to the operation of the scanning driver 23, and the reference driver 22 prevents the polar liquid from moving with respect to each of the plurality of reference electrodes 19. One voltage of the non-selection voltage and the selection voltage that allows the polar liquid to move according to the signal voltage Vd is applied as the reference voltage Vr.

In the image display device 1, for example, the scanning driver 23 sequentially applies a selection voltage to the scanning electrodes 20 from the left side to the right side of FIG. 15, and the reference driver 22 is synchronized with the operation of the scanning driver 23. The scanning operation for each line is performed by sequentially applying a selection voltage to the reference electrodes 19 from the left side to the right side of 15 (details will be described later).

Further, the signal driver 21, the reference driver 22, and the scanning driver 23 include a DC power source or an AC power source, and supply corresponding signal voltage Vd, reference voltage Vr, and scanning voltage Vs. .

The reference driver 22 is configured to switch the polarity of the reference voltage Vr every predetermined time (for example, one frame). Furthermore, the scanning driver 23 is configured to switch each polarity of the scanning voltage Vs in response to switching of the polarity of the reference voltage Vr. Thus, since the polarities of the reference voltage Vr and the scanning voltage Vs are switched every predetermined time, these references are compared to when the same polarity voltage is always applied to the reference electrode 19 and the scanning electrode 20. It is possible to prevent the charge from being localized in the electrode 19 and the scanning electrode 20. Furthermore, it is possible to prevent adverse effects of display defects (afterimage phenomenon) and reliability (lifetime reduction) due to charge localization.

Here, the pixel structure of the display element 2 ′ will be specifically described with reference to FIGS. 16 to 22.

FIG. 16 is a plan view showing an effective display portion and an ineffective display portion on the display surface of the display element shown in FIG. FIG. 17 is a diagram illustrating the pixel area in the effective display section and the dummy pixel area in the non-effective display section shown in FIG. FIG. 18 is an enlarged plan view showing a main configuration of the upper substrate side in the effective display section shown in FIG. 16 when viewed from the display surface side. FIG. 19 is an enlarged plan view showing a main configuration of the lower substrate side in the effective display section shown in FIG. 16 when viewed from the non-display surface side. FIG. 20 is an enlarged plan view showing a main configuration of the upper substrate side in the ineffective display portion shown in FIG. 16 when viewed from the display surface side. FIG. 21 is an enlarged plan view showing a main configuration of the lower substrate side in the non-effective display portion shown in FIG. 16 when viewed from the non-display surface side. 22 (a) and 22 (b) are cross-sectional views showing the main configuration of the display element shown in FIG. 15 during CF color display and non-CF color display, respectively.

As shown in FIG. 16, in the display element 2 ', an effective display portion ED and a non-effective display portion ND are set on the display surface, as in the first embodiment. Specifically, as shown in FIG. 16, in the display element 2 ′, an effective display portion ED that tightens a large area of the display surface having a rectangular shape including the center of the display surface, and the effective display portion ED are provided. A non-effective display portion ND provided so as to surround is set. The effective display portion ED includes a plurality of the pixel regions P (FIG. 17) provided to divide the display space K (FIG. 22) by the ribs 11 (FIG. 19). On the other hand, the non-effective display portion ND includes a plurality of dummy pixel regions DP (FIG. 17) as dummy regions.

In the display element 2 ′, the size of the dummy region (the total size of the plurality of dummy pixel regions DP) is the polar liquid 12 ′ enclosed in each of the plurality of pixel regions P and the insulating fluid. Is determined based on the amount of oil 13 'enclosed.

More specifically, when the display element 2 forms a 3 × 1 RGB specification display panel with QVGA (Quarter Video Graphics Graphics Array), for example, in the X direction of the effective display unit ED (for example, the horizontal direction of the display panel). The number of pixel regions P (number of pixels) is 320 pixels, and the number (pixel number) of pixel regions P in the Y direction (for example, the vertical direction of the display panel) of the effective display portion ED is 240 × 3 (RGB). Pixel. The number (number of pixels) of dummy pixel regions DP in the X direction of the ineffective display portion ND is 5 pixels in each of the left and right portions of the effective display portion ED, and the dummy pixels in the Y direction of the ineffective display portion ND. The number of the regions DP (number of pixels) is 5 pixels in each of the upper part and the lower part of the effective display portion ED.

More specifically, in the upper right part of the display element 2 ′, as shown in FIG. 17, the pixel area P included in the effective display part ED is provided with 3 pixels and 6 pixels in the X direction and the Y direction, respectively. Further, dummy pixel regions DP included in the ineffective display portion ND of 5 pixels are provided in the X direction and the Y direction so as to surround the 18 pixel regions P. Further, the pixel region P and the dummy pixel region DP are divided into the same shape by the ribs 11 as the partition walls. In addition, in each pixel region P of the effective display portion ED, color filter portions (openings) 25r, 25g, and 25b of any color are formed. On the other hand, the opening is not formed in each dummy pixel region DP of the non-effective display portion ND, and is shielded from light by a black matrix portion 10s described later as a light shielding film.

In addition, each pixel region P of the effective display portion ED is filled with polar liquid 12 ′ and oil 13 ′, and each dummy pixel region DP of the non-effective display portion ND is filled with polar liquid 12 ′ and predetermined liquid. Oil 13 'is enclosed. However, as illustrated in FIG. 17, in the dummy pixel region DP, particularly in the dummy pixel region DP close to the outermost peripheral portion, part of the polar liquid 12 ′ is evaporated during the manufacturing process of the display element 2, and the amount of the liquid is reduced. It is less than the appropriate amount of polar liquid 12 ′ in each pixel region P.

16 to 22, the display element 2 ′ includes the upper substrate 6 as the first substrate provided on the display surface side and the back surface side of the upper substrate 6 (as in the first embodiment). And the lower substrate 7 as the second substrate provided on the non-display surface side. In the display element 2 ′, a predetermined display space K is formed between the upper substrate 6 and the lower substrate 7. However, the display space K functions in the effective display portion ED, and does not function in the ineffective display portion ND. The display space K is filled with polar liquid 12 ′ and oil 13 ′ so as to be movable in the X direction inside the display space K. The polar liquid 12 ′ is in the effective display area P1. It can move to the side or the non-effective display area P2 side.

Further, in the display element 2 ′ of the present embodiment, unlike the first embodiment, as the polar liquid 12 ′, for example, one that is colored black by a self-dispersing pigment is used, and the oil 13 ′ is colorless and transparent. Oil is used. Specifically, for example, a mixed liquid of ethylene glycol and water and the pigment are used for the polar liquid 12 '. For example, colorless and transparent alkane oil is used as the oil 13 '. That is, in the display element 2 ′ of the present embodiment, the polar liquid 12 ′ functions as a shutter that allows or blocks light transmission in each pixel.

Further, in each pixel of the display element 2 ′ of the present embodiment, as will be described in detail later, the polar liquid 12 ′ is disposed inside the display space K on the reference electrode 19 side (effective display region P1 side) or on the scanning electrode 20 side. The display color is changed to one of black or red display, green display, and blue display (CF color display) by sliding to the (ineffective display area P2 side).

Further, a color filter layer 25, a signal electrode 18 as a first electrode, and a water repellent film 24 are sequentially formed on the surface of the upper substrate 6 on the non-display surface side. However, as illustrated in FIG. 18, the signal electrode 18 is provided on the non-display surface side of the upper substrate 6 corresponding to the pixel region P included in the effective display portion ED (on the surface of the color filter layer 25). 19, as illustrated in FIG. 19, the surface side of the upper substrate 6 corresponding to the dummy pixel region DP included in the ineffective display portion ND (on the surface of the color filter layer 25). ) Is not formed. More specifically, the signal electrode 18 is on the non-display surface side of the upper substrate 6 only in the portion of the effective display portion ED and the portion of the non-effective display portion ND between the signal driver 21 and the effective display portion ED. It is provided on the surface side.

Further, the reference electrode 19 and the scan electrode 20 as second electrodes are provided on the surface of the lower substrate 7 on the display surface side, and further, the reference electrode 19 and the scan electrode 20 are covered. The dielectric layer 14 is formed. However, as illustrated in FIG. 19, the reference electrode 19 and the scanning electrode 20 are formed only on the surface on the display surface side of the lower substrate 7 corresponding to the pixel region P included in the effective display portion ED. As illustrated in FIG. 21, it is not formed on the display surface side surface of the lower substrate 7 corresponding to the dummy pixel region DP included in the ineffective display portion ND.

More specifically, the reference electrode 19 is provided on the display surface side of the lower substrate 7 only in the portion of the effective display portion ED and the portion of the non-effective display portion ND between the reference driver 22 and the effective display portion ED. On the surface. Similarly, the scanning electrode 20 is formed on the display surface side surface of the lower substrate 7 only in the portion of the effective display portion ED and the portion of the non-effective display portion ND between the scan driver 23 and the effective display portion ED. Is provided.

The dielectric layer 14 is formed on the surface on the display surface side of the lower substrate 7 corresponding to each of the pixel region P included in the effective display portion ED and the dummy pixel region DP included in the ineffective display portion ND. ing. Further, the surface on the display surface side of the dielectric layer 14 is provided with a first rib member 11a and a first rib member 11a provided in parallel to the X direction and the Y direction, respectively, as in the first embodiment. Ribs 11 having two rib members 11b are provided. Further, the lower substrate 7 is provided with a water repellent film 15 so as to cover the dielectric layer 14 and the ribs 11.

Similar to the first embodiment, the color filter layer 25 has red (R), green (G), and blue (B) color filter portions 25r, 25g, and 25b, and a light shielding layer. A black matrix portion 25s as a film is provided, and constitutes pixels of each color of RGB. That is, in the color filter layer 25, as illustrated in FIG. 18, RGB color filter portions 25r, 25g, and 25b are sequentially provided along the X direction, and three color filter portions 25r, 25g, and 25b are respectively provided as Y. A total of nine pixels are arranged in the X direction and the Y direction, respectively.

Further, in the display element 2 ′, as illustrated in FIG. 18, in each pixel region P, any one of RGB color filter portions 25r, 25g, and 25b is provided at a location corresponding to the effective display region P1 of the pixel. A black matrix portion 25s is provided at a location corresponding to the ineffective display area P2. That is, in the display element 2 ′, an ineffective display region P2 (non-opening portion) is set for the display space K by the black matrix portion (light-shielding film) 25s, and the opening portion formed in the black matrix portion 25s. The effective display area P1 is set by (that is, any one of the color filter portions 25r, 25g, and 25b).

In the display element 2 ′, the area of the color filter portions 25 r, 25 g, and 25 b is selected to be the same or slightly smaller than the area of the effective display area P 1. On the other hand, the area of the black matrix portion 25s is selected to be the same or slightly larger than the area of the ineffective display area P2. In FIG. 18, in order to clarify the boundary between adjacent pixels, the boundary between the two black matrix portions 25s corresponding to the adjacent pixels is indicated by a dotted line, but the actual color filter layer 25 is shown. Then, there is no boundary line between the black matrix portions 25s.

Further, in the display element 2 ′, the display space K is divided in units of pixel areas P by the ribs 11 as the partition walls, as in the first embodiment. That is, in the display element 2 ′, the display space K of each pixel is, as illustrated in FIG. 19, two first rib members 11 a having appropriate heights facing each other and appropriate heights facing each other. Are divided by the two second rib members 11b. Furthermore, in the display element 2 ′, the polar liquid 12 ′ can be easily placed inside the display space K of the adjacent pixel region P by the first and second rib members 11a and 11b, as in the first embodiment. It is prevented from flowing into. That is, for example, negative-type photocurable resin is used for the first and second rib members 11a and 11b, and the first and second rib members 11a and 11b are light transmissive. Further, in these first and second rib members 11a and 11b, the protruding height from the dielectric layer 14 is determined so that the polar liquid 12 ′ is prevented from flowing in and out between adjacent pixels. .

Further, in the display element 2 ′, as illustrated in FIG. 20, only the black matrix portion 10s provided on the non-display surface side surface of the upper substrate 6 is provided in each dummy pixel region DP of the ineffective display portion ND. It has been. That is, the ineffective display portion ND is set by a light shielding film provided on the upper substrate (first substrate) 6 side. In FIG. 20, in order to clarify the boundary portion between adjacent dummy pixels, the boundary line between the two black matrix portions 10s corresponding to the adjacent dummy pixels is indicated by a dotted line. In the portion 10s, there is no boundary line between the black matrix portions 10s.

Further, as illustrated in FIG. 21, in the non-effective display portion ND, the display space K is divided into dummy pixel regions DP by the ribs 11 as in the effective display portion ED. On the other hand, in this ineffective display part ND, unlike the effective display part ED, the reference electrode 19 and the scanning electrode 20 are not installed.

For the reference electrode 19 and the scanning electrode 20, a transparent electrode material such as indium oxide (ITO), tin oxide (SnO ₂ ), or zinc oxide (AZO, GZO, or IZO) is used. Each of these reference electrodes 19 and each scanning electrode 20 is formed in a strip shape on the lower substrate 7 by a known film forming method such as sputtering.

The signal electrode 18 uses a linear wiring arranged so as to be parallel to the X direction. The signal electrode 18 is made of a transparent electrode material such as ITO. Further, the signal electrode 18 is disposed on the color filter layer 25 so as to pass through the substantially central portion in the X direction of each pixel region P, and is electrically connected to the polar liquid 12 ′ via the water repellent film 24. It is comprised so that it may contact. Thereby, in the display element 2 ', the response of the polar liquid 12' during the display operation is improved.

The water-repellent film 24 is made of a transparent synthetic resin, preferably, for example, a fluorine-based resin that becomes a hydrophilic layer with respect to the polar liquid 12 'when a voltage is applied. Thereby, in the display element 2 ′, wettability (contact angle) with the polar liquid 12 ′ on the surface side of the upper substrate 6 on the display space K side can be greatly changed. The movement (deformation) speed can be increased.

In each pixel of the display element 2 ′ configured as described above, when the polar liquid 12 ′ is held between the black matrix portion 25 s and the reference electrode 19 as illustrated in FIG. Light from the light 16 passes through the color filter portion 25r without being blocked by the polar liquid 12 ', thereby performing red display (CF color display). On the other hand, as illustrated in FIG. 22B, when the polar liquid 12 ′ is held between the color filter portion 25r and the scan electrode 20, the light from the backlight 16 is blocked by the polar liquid 12 ′. Black display (non-CF color display) is performed.

Here, with reference to FIGS. 23 to 27, the manufacturing process of the display element 2 'of the present embodiment will be specifically described.

23 (a) to 23 (d) are diagrams for explaining the formation process on the upper substrate side shown in FIG. 24 (a) to 24 (e) are diagrams for explaining the formation process on the lower substrate side shown in FIG. FIG. 25 is a diagram illustrating a process of enclosing polar liquid in the dummy pixel region in the ineffective display section shown in FIG. FIG. 26 is a diagram for explaining a process of enclosing the polar liquid into the pixel region in the effective display section shown in FIG. FIG. 27A is a diagram illustrating a process of bonding the upper substrate and the lower substrate illustrated in FIG. 22, and FIG. 27B illustrates a final manufacturing process of the display element illustrated in FIG. 15. It is a figure to do.

In FIG. 23A, a non-alkali glass substrate having a thickness of 0.7 mm, for example, is used for the upper substrate 6, and the color filter portions 25r, 25g, 25b and the black matrix portion are formed by using, for example, a photolithography method. 25 s is stacked on the surface of the upper substrate 6 to perform a CF forming step, and the color filter layer 25 is formed. The color filter layer 25 uses a photosensitive resin (for example, photoreactive acrylic monomer) and a corresponding pigment, and has a thickness of, for example, about 2 μm. Further, the color filter portions 25r, 25g, and 25b are formed only on the effective display portion ED (FIG. 16) and are not formed on the non-effective display portion ND (FIG. 16). That is, as shown in FIG. 23B, in the ineffective display portion ND, only the black matrix portion 10s is formed on the surface of the upper substrate 6.

Subsequently, as shown in FIG. 23C, an electrode forming step of the signal electrode 18 is performed in the effective display portion ED. That is, in this electrode formation step, the signal electrode 18 is installed by fixing a thin wire made of, for example, ITO on the surface of the color filter layer 25, for example.

Next, as shown in FIG. 23D, a film forming process of the water repellent film 24 is performed. That is, a water-repellent film 24 was formed by applying, for example, a fluorine-based resin material to each surface of the color filter layer 25 and the signal electrode 18 by dipping and baking at 80 ° C. for 30 minutes. The film thickness of the water repellent film 24 is, for example, 60 nm.

In FIG. 24A, a non-alkali glass substrate having a thickness of, for example, 0.7 mm is used for the lower substrate 7, and the formation process of the reference electrode 19 and the scanning electrode 20 is performed in the effective display portion ED. Is called. That is, in this forming step, the reference electrode 19 and the scanning electrode 20 are formed by forming an ITO film having a thickness of 100 nm on the surface of the lower substrate 7 by, for example, sputtering.

Next, as shown in FIG. 24 (b), a step of forming the dielectric layer 14 is performed. That is, a silicon nitride film was formed as the dielectric layer 14 on the reference electrode 19 and the scanning electrode 20 by using, for example, a CVD method. The film thickness of the dielectric layer 14 is, for example, 350 nm. In the non-effective display portion ND, as shown in FIG. 24C, the reference electrode 19 and the scanning electrode 20 are not formed, and only the dielectric layer 14 is formed on the surface of the lower substrate 7. .

Subsequently, as shown in FIG. 24D, an installation step of providing the rib 11 on the dielectric layer 14 is performed. That is, in this installation step, the first and second rib members 11a and 11b using photo-curing resin are formed on the surface of the dielectric layer 14 in the pixel region P unit and the dummy pixel region DP unit. The Further, by performing this installation process, a plurality of pixel areas P are set in the effective display area ED, and a dummy pixel area (dummy area) DP is set in the ineffective display area ND surrounding the effective display area ED. The area setting process is completed.

Next, as shown in FIG. 24 (e), a forming step of forming a water repellent film 15 on the surface of the dielectric layer 14 and the first and second rib members 11a and 11b is performed. That is, in this forming step, for example, a fluorine-based resin material is applied to the surface of the dielectric layer 14 and the first and second rib members 11a and 11b by dipping and baked at 80 ° C. for 30 minutes. Thus, the water repellent film 15 is formed.

Subsequently, an encapsulating step of the polar liquid 12 ′ is performed on the lower substrate 6. In this encapsulating step, first, the dummy pixel region DP of the ineffective display portion ND is performed, and then the pixel region P of the effective display portion ED is performed.

That is, as shown in FIG. 25, a first enclosing step of enclosing a polar liquid 12 ′ as a predetermined liquid into each dummy pixel region DP of the ineffective display portion ND by, for example, a dispenser method or an ink jet method. Is done.

Subsequently, as shown in FIG. 26, for each pixel region P of the effective display portion ED, a second sealing step of sealing the polar liquid 12 'is performed by, for example, a dispenser method or an inkjet method.

Next, as shown in FIG. 27A, a process of assembling the upper substrate 6 from above and bonding the upper substrate 6 and the lower substrate 7 to the lower substrate 7 holding the polar liquid 12 ′ is performed. .

Thereafter, in FIG. 27B, a step of encapsulating the oil 13 'using the capillary phenomenon from the gap between the pixel areas P and the gap between the dummy pixel areas DP is performed. Then, the display element 10 is completed by installing the backlight 16 on the lower substrate 7 side.

Here, the display operation of the image display apparatus 1 of the present embodiment configured as described above will be specifically described with reference to FIG.

FIG. 28 is a diagram for explaining an operation example of the image display device shown in FIG.

In FIG. 28, the reference driver 22 and the scanning driver 23 select the reference voltage Vr and the scanning voltage Vs as the reference voltage Vr and the scanning voltage Vs, respectively, with respect to the reference electrode 19 and the scanning electrode 20 in a predetermined scanning direction from the left to the right in FIG. Apply voltage sequentially. Specifically, the reference driver 22 and the scan driver 23 sequentially apply an H voltage (first voltage) and an L voltage (second voltage) as selection voltages to the reference electrode 19 and the scan electrode 20, respectively. The scanning operation for selecting the line is performed. In this selection line, the signal driver 21 applies the H voltage or the L voltage as the signal voltage Vd to the corresponding signal electrode 18 according to the image input signal from the outside. Thereby, in each pixel of the selection line, the polar liquid 12 'is moved to the effective display area P1 side or the non-effective display area P2 side, and the display color on the display surface side is changed.

On the other hand, the reference driver 22 and the scan driver 23 apply the above-mentioned non-selection voltages as the reference voltage Vr and the scan voltage Vs to the non-selected lines, that is, all the remaining reference electrodes 19 and scan electrodes 20, respectively. Specifically, the reference driver 22 and the scan driver 23 apply an intermediate voltage (Middle) that is, for example, an intermediate voltage between the H voltage and the L voltage to the remaining reference electrodes 19 and scan electrodes 20 as non-selection voltages. Voltage, hereinafter referred to as “M voltage”). Thereby, in each pixel of the non-selected line, the polar liquid 12 ′ is stopped without causing unnecessary fluctuation on the effective display region P 1 side or the non-effective display region P 2 side, and the display color on the display surface side is not changed.

When performing the display operation as described above, combinations of voltages applied to the reference electrode 19, the scanning electrode 20, and the signal electrode 18 are as shown in Table 1. Further, as shown in Table 1, the behavior of the polar liquid 12 ′ and the display color on the display surface side depend on the applied voltage.

<Operation on selected line>
In the selection line, for example, when an H voltage is applied to the signal electrode 18, an H voltage is applied between the reference electrode 19 and the signal electrode 18. There is no potential difference between the electrode 18 and the electrode 18. On the other hand, since the L voltage is applied to the scanning electrode 20 between the signal electrode 18 and the scanning electrode 20, a potential difference is generated. For this reason, the polar liquid 12 ′ moves in the display space K toward the scanning electrode 20 where a potential difference is generated with respect to the signal electrode 18. As a result, as illustrated in FIG. 22B, the polar liquid 12 ′ moves to the effective display region P1 side, moves the oil 13 to the reference electrode 19 side, and illuminates light from the backlight 16. Is prevented from reaching the color filter portion 25r. Thereby, the display color on the display surface side is in a black display (non-CF color display) state by the polar liquid 12 ′.

On the other hand, when the L voltage is applied to the signal electrode 18 in the selected line, a potential difference is generated between the reference electrode 19 and the signal electrode 18, and between the signal electrode 18 and the scanning electrode 20. No potential difference has occurred. Accordingly, the polar liquid 12 ′ moves in the display space K toward the reference electrode 19 where a potential difference is generated with respect to the signal electrode 18. As a result, as illustrated in FIG. 22A, the polar liquid 12 ′ moves to the ineffective display region P2 side, and allows the illumination light from the backlight 16 to reach the color filter portion 25r. . As a result, the display color on the display surface side is in a red display (CF color display) state by the color filter unit 25r. Further, in the image display device 1, when the polar liquid 12 ′ moves to the non-effective display area P 2 side in all three adjacent RGB pixels and the CF color display is performed, the RGB pixels are concerned. The red light, green light, and blue light from are mixed with white light, and white display is performed.

<Operation on unselected lines>
In the non-selected line, for example, when the H voltage is applied to the signal electrode 18, the polar liquid 12 ′ is kept stationary at the current position and is maintained at the current display color. That is, since the M voltage is applied to both the reference electrode 19 and the scan electrode 20, the potential difference between the reference electrode 19 and the signal electrode 18 and the potential difference between the scan electrode 20 and the signal electrode 18 are as follows. This is because the same potential difference occurs in both cases. As a result, the display color is maintained unchanged from the current black display or CF color display.

Similarly, even when the L voltage is applied to the signal electrode 18 in the non-selected line, the polar liquid 12 ′ is maintained in a stationary state at the current position and is maintained at the current display color. That is, since the M voltage is applied to both the reference electrode 19 and the scan electrode 20, the potential difference between the reference electrode 19 and the signal electrode 18 and the potential difference between the scan electrode 20 and the signal electrode 18 are as follows. This is because the same potential difference occurs in both cases.

As described above, in the non-selected line, even if the signal electrode 18 is either the H voltage or the L voltage, the polar liquid 12 ′ does not move but remains stationary and display on the display surface side. The color does not change.

On the other hand, in the selection line, the polar liquid 12 ′ can be moved according to the voltage applied to the signal electrode 18 as described above, and the display color on the display surface side can be changed.

Further, in the image display device 1, the display color at each pixel on the selected line is applied to the signal electrode 18 corresponding to each pixel, for example, as shown in FIG. 28, by the combination of applied voltages shown in Table 1. Depending on the voltage, the color filter portions 25r, 25g, and 25b are colored with CF (red, green, or blue) or nonpolarized with a polar liquid 12 ′ (black). Further, when the reference driver 22 and the scanning driver 23 perform the scanning operation of the selection lines of the reference electrode 19 and the scanning electrode 20 from the left to the right in FIG. 28, for example, each pixel in the display unit of the image display device 1 is scanned. The display color also changes sequentially from left to right in FIG. Therefore, by performing the scanning operation of the selection line by the reference driver 22 and the scanning driver 23 at high speed, the display color of each pixel on the display unit can be changed at high speed in the image display device 1. Furthermore, by applying the signal voltage Vd to the signal electrode 18 in synchronization with the scanning operation of the selected line, the image display apparatus 1 can perform various information including moving images based on an image input signal from the outside. Can be displayed.

Further, the combinations of voltages applied to the reference electrode 19, the scan electrode 20, and the signal electrode 18 are not limited to Table 1 but may be those shown in Table 2.

In other words, the reference driver 22 and the scan driver 23, for example, select L voltage (second voltage) and H as selection voltages with respect to the reference electrode 19 and the scan electrode 20 in a predetermined scanning direction from the left side to the right side in FIG. A scanning operation is performed in which a voltage (first voltage) is sequentially applied to select lines. In this selection line, the signal driver 21 applies the H voltage or the L voltage as the signal voltage Vd to the corresponding signal electrode 18 according to the image input signal from the outside.

On the other hand, the reference driver 22 and the scan driver 23 apply the M voltage as the non-selection voltage to the non-selected lines, that is, the remaining reference electrodes 19 and scan electrodes 20.

<Operation on selected line>
In the selection line, for example, when an L voltage is applied to the signal electrode 18, an L voltage is applied between the reference electrode 19 and the signal electrode 18. There is no potential difference between the electrode 18 and the electrode 18. On the other hand, between the signal electrode 18 and the scan electrode 20, since the H voltage is applied to the scan electrode 20, a potential difference is generated. Accordingly, the polar liquid 12 ′ moves in the display space K toward the scanning electrode 20 where a potential difference is generated with respect to the signal electrode 18. As a result, as illustrated in FIG. 22B, the polar liquid 12 ′ moves to the effective display region P1 side, moves the oil 13 to the reference electrode 19 side, and illuminates light from the backlight 16. Is prevented from reaching the color filter portion 25r. Thereby, the display color on the display surface side is in a black display (non-CF color display) state by the polar liquid 12 ′.

On the other hand, when the H voltage is applied to the signal electrode 18 in the selection line, a potential difference is generated between the reference electrode 19 and the signal electrode 18, and between the signal electrode 18 and the scanning electrode 20. No potential difference has occurred. Accordingly, the polar liquid 12 ′ moves in the display space K toward the reference electrode 19 where a potential difference is generated with respect to the signal electrode 18. As a result, as illustrated in FIG. 22A, the polar liquid 12 ′ moves to the ineffective display region P2 side, and allows the illumination light from the backlight 16 to reach the color filter portion 25r. . As a result, the display color on the display surface side is in a red display (CF color display) state by the color filter unit 25r. Further, in the image display device 1, when the polar liquid 12 ′ moves to the non-effective display area P 2 side in all three adjacent RGB pixels and the CF color display is performed, the RGB pixels are concerned. The red light, green light, and blue light from are mixed with white light, and white display is performed.

<Operation on unselected lines>
In the non-selected line, for example, when the L voltage is applied to the signal electrode 18, the polar liquid 12 ′ is maintained stationary at the current position and is maintained at the current display color. That is, since the M voltage is applied to both the reference electrode 19 and the scan electrode 20, the potential difference between the reference electrode 19 and the signal electrode 18 and the potential difference between the scan electrode 20 and the signal electrode 18 are as follows. This is because the same potential difference occurs in both cases. As a result, the display color is maintained unchanged from the current black display or CF color display.

Similarly, even when the H voltage is applied to the signal electrode 18 in the non-selected line, the polar liquid 12 ′ is maintained in a stationary state at the current position and is maintained at the current display color. That is, since the M voltage is applied to both the reference electrode 19 and the scan electrode 20, the potential difference between the reference electrode 19 and the signal electrode 18 and the potential difference between the scan electrode 20 and the signal electrode 18 are as follows. This is because the same potential difference occurs in both cases.

As described above, even in the case shown in Table 2, as in the case shown in Table 1, in the non-selected line, even if the signal electrode 18 is either the H voltage or the L voltage, the polar liquid 12 'does not move, stops, and the display color on the display surface side does not change.

On the other hand, in the selection line, the polar liquid 12 ′ can be moved according to the voltage applied to the signal electrode 18 as described above, and the display color on the display surface side can be changed.

Further, in the image display device 1 of the present embodiment, in addition to the combinations of applied voltages shown in Tables 1 and 2, the applied voltage to the signal electrode 18 is not limited to the binary value of the H voltage or the L voltage. The voltage between the H voltage and the L voltage can be changed according to information displayed on the display surface side. In other words, the image display device 1 can perform gradation display by controlling the signal voltage Vd. Thereby, the display element 2 ′ having excellent display performance can be configured.

With the above configuration, the present embodiment can achieve the same operations and effects as the first embodiment. In the display element 2 ′ of the present embodiment, the signal electrode 18 installed in the display space K is used as the first electrode, and the effective display area P1 and the ineffective display area are used as the second electrodes. The reference electrode 19 and the scanning electrode 20 provided on the lower substrate 7 are used so as to be installed on one side and the other side of P2, respectively. Thus, in the present embodiment, unlike the first embodiment, the display color on the display surface side can be changed without providing a switching element, and a display element 2 ′ having a simple structure can be configured. it can. In addition, in the display element 2 ′ according to the present embodiment, the three electrodes are provided and the conductive liquid 12 is slid. Therefore, the display on the display surface side is compared with the display element 2 ′ that changes the shape of the conductive liquid 12. It is possible to easily increase the color switching speed and save labor.

In the display element 2 ′ of the present embodiment, the signal driver (signal voltage applying unit) 21, the reference driver (reference voltage applying unit) 22, and the scanning driver (scanning voltage applying unit) 23 are the signal electrode 18 and the reference electrode 19. The signal voltage Vd, the reference voltage Vr, and the scanning voltage Vs are applied to the scanning electrode 20. Thereby, in the present embodiment, the matrix drive type display element 2 ′ having excellent display quality can be easily configured, and the display color of each pixel region can be appropriately changed.

[Third Embodiment]
FIG. 29 is a plan view showing a pixel region in the effective display portion and a dummy region in the ineffective display portion of the display element according to the third embodiment of the present invention. In the figure, the main difference between the present embodiment and the second embodiment is that the dummy region is partitioned by ribs in a shape different from the pixel region. In addition, about the element which is common in the said 2nd Embodiment, the same code | symbol is attached | subjected and the duplicate description is abbreviate | omitted.

That is, as shown in FIG. 29, in the display element 2 ′ of the present embodiment, an ineffective display portion ND is provided so as to surround the effective display portion ED. In other words, in the display element 2 ′ of the present embodiment, a frame-like ineffective display portion ND is set as in the second embodiment. Further, when a 3 × 1 RGB specification display panel is configured by the above QVGA (Quarter Video Graphics Array), the non-effective display portion ND sets the dimension H1 in the Y direction and the dimension H2 in the X direction to about 0.2 mm, for example. Has been. However, these dimensions H1 and H2 are appropriately changed according to the size of the dummy area DA described below.

Further, unlike the second embodiment, the ineffective display portion ND does not include the dummy pixel region DP, and the corresponding upper substrate 6 and lower substrate 7 are separated by ribs 34. The dummy area DA is provided. That is, as illustrated in FIG. 29, the dummy area DA is partitioned by the ribs 34 in a shape different from that of the pixel area P. Further, in the frame-shaped ineffective display portion ND, one or a plurality of dummy areas DA are provided in each of two portions parallel to the X direction and each of two portions parallel to the Y direction.

In the ineffective display area ND, the size of the dummy area DA (the total size of all the dummy areas DA) is enclosed in each of the plurality of pixel areas P, as in the second embodiment. It is determined on the basis of the enclosed amount of the polar liquid 12 ′ and the oil 13 ′. In the dummy area DA, at least one of the polar liquid 12 ′ and the oil 13 ′, for example, the polar liquid 12 ′ is sealed as a predetermined liquid.

With the above configuration, the present embodiment can achieve the same operations and effects as those of the second embodiment. In this embodiment, since the dummy area DA is partitioned by the rib 34 in a shape different from that of the pixel area P, the ineffective display portion is compared with the case where the dummy area is partitioned in the same shape as the pixel area P. The size of ND can be easily reduced.

It should be noted that all of the above embodiments are illustrative and not restrictive. The technical scope of the present invention is defined by the claims, and all modifications within the scope equivalent to the configurations described therein are also included in the technical scope of the present invention.

For example, in the above description, the case where the present invention is applied to an image display apparatus provided with a display unit has been described. However, the present invention is an electric device provided with a display unit that displays information including characters and images. The present invention is not limited in any way. For example, it can be suitably used for a portable information terminal such as a PDA such as an electronic notebook, a display device attached to a personal computer, a television, or the like, or an electronic paper or other electric device including various display units. it can.

In the above description, the case where an electrowetting type display element that moves the polar liquid in accordance with the application of an electric field to the polar liquid has been described. However, the display element of the present invention is not limited to this. It is not limited as long as it is an electric field induction type display element that can change the display color on the display surface side by operating a polar liquid inside the display space using an external electric field. Instead, the present invention can be applied to other types of electric field induction display elements such as an electroosmosis method, an electrophoresis method, and a dielectrophoresis method.

However, when the electrowetting type display element is configured as in the above embodiments, the polar liquid can be moved at a high speed with a low driving voltage. Further, in the electrowetting type display element, the display color is changed according to the movement of the polar liquid, and unlike a liquid crystal display device using a birefringent material such as a liquid crystal layer, it is used for information display. It is also preferable in that a high-luminance display element that is excellent in light utilization efficiency of light from the backlight and external light can be easily configured.

In the above description, the case where a mixed liquid of ethylene glycol and water is used as a polar liquid has been described. However, the polar liquid of the present invention is not limited to this. Specifically, polar liquids include potassium chloride, zinc chloride, potassium hydroxide, sodium hydroxide, alkali metal hydroxide, zinc oxide, sodium chloride, lithium salt, phosphoric acid, alkali metal carbonate, oxygen ion What contains electrolytes, such as ceramics which have conductivity, can be used. In addition to water, organic solvents such as alcohol, acetone, formamide, and ethylene glycol can also be used as the solvent. Furthermore, the polar liquid of the present invention includes an ionic liquid containing a cation such as pyridine, alicyclic amine, or aliphatic amine, and an anion such as fluoride such as fluoride ion or triflate ( Room temperature molten salt) can also be used.

The polar liquid of the present invention includes a conductive liquid having conductivity and a liquid having a high dielectric constant having a specific dielectric constant of a predetermined value or higher, preferably 15 or higher.

However, as in each of the above-described embodiments, the use of a mixed liquid containing water as a polar liquid is superior in handleability and can easily constitute a display element that is easy to manufacture. preferable.

In the above description, the case where nonpolar oil is used has been described. However, the present invention is not limited to this, and any insulating fluid that does not mix with polar liquid may be used. Air may be used. Moreover, silicone oil, aliphatic hydrocarbons, etc. can be used as oil. The insulating fluid of the present invention includes a fluid having a relative dielectric constant of not more than a predetermined value, preferably not more than 5.

However, as in each of the above-described embodiments, the use of nonpolar oil that is not compatible with polar liquid is more polar in the nonpolar oil than when air and polar liquid are used. It is preferable in that the liquid droplets can be moved more easily, the polar liquid can be moved at high speed, and the display color can be switched at high speed.

In the description of the first embodiment, the case where a thin film transistor is used as the switching element has been described. However, the switching element of the present invention is not limited to this, and other switching elements such as an MIM element are used. It can also be used.

In the description of the first embodiment, a case has been described in which the dielectric layer provided on the lower substrate (one side of the first and second substrates) is used as the capacitor so as to cover the pixel electrode. However, the capacitor of the present invention is not limited as long as it can hold the charge supplied to the pixel electrode (second electrode). Specifically, when a capacitor (discrete component) is installed as a capacitor, or when a pixel electrode is embedded inside one side of the first and second substrates, the substrate may be used as a capacitor. it can. Further, a substrate in which a water-repellent film is coated on the pixel electrode of the lower substrate can be regarded as a state in which a capacitor is formed for each pixel.

However, in the case of using the dielectric layer as in the above embodiments, it is possible to omit the installation of a capacitor composed of discrete components, and a display device with a simple structure can be easily configured.

In the description of each of the second and third embodiments, the case of using a colorless and transparent oil and a polar liquid colored in black has been described. However, the present invention is not limited to this, for example, RGB, cyan (C), magenta (M), yellow (Y) CMY, RGBYC, etc. so that a plurality of pixel regions are provided in accordance with a plurality of colors capable of full color display on the display surface side. It is also possible to use a plurality of polar liquids that are colored. When the polar liquid colored in this way is used, the installation of the color filter layer can be omitted in the second and third embodiments.

In the description of each of the first to third embodiments, the case where a polar liquid and oil (insulating fluid) are sealed as predetermined liquids in the dummy area (including the dummy pixel area) is used. As described above, the predetermined liquid of the present invention is not limited as long as it can suppress evaporation of the polar liquid and the insulating fluid sealed in the inside of each of the plurality of pixel areas provided inside the dummy area. .

However, as in each of the above embodiments, the predetermined liquid is preferably a liquid having the same or similar composition as the polar liquid and the insulating fluid sealed in the inside of each pixel region. When used, it is more preferable in that the number of parts of the display element can be reduced, and an inexpensive display element can be easily configured. Specifically, in the case of the first embodiment, oil is sealed into the inside of each pixel region before the upper substrate (first substrate) and the lower substrate (second substrate) are bonded together. It is preferable to use alkane oil containing the composition of the oil, toluene, or a mixture thereof as the predetermined liquid. Further, in each of the second and third embodiments, the polar liquid is sealed into the inside of each pixel region before the upper substrate (first substrate) and the lower substrate (second substrate) are bonded together. In some cases, water containing the polar liquid composition is preferably used as the predetermined liquid.

In the description of the first to third embodiments, the ineffective display area and the ineffective display area in each of the plurality of pixel areas in the effective display area are provided on the upper substrate (first substrate) side. However, the present invention is not limited to this. For example, the non-effective display portion and the non-effective display area may be set using separate light-shielding films. Further, for example, the ineffective display portion may be set by a light shielding film provided on at least one side of the upper substrate (first substrate) and the lower substrate (second substrate).

However, as in each of the above-described embodiments, a display element with a simple structure is easier when the ineffective display portion and the ineffective display area are set by the same light-shielding film provided on the first substrate side. It is preferable at the point which can be comprised.

In the description of each of the first to third embodiments, the case where a transmissive display element including a backlight is configured has been described. However, the present invention is not limited to this, and the diffuse reflector The present invention can also be applied to a reflection type having a light reflection part such as a transflective display element in which the light reflection part and a backlight are used in combination.

In the description of the second and third embodiments, the signal electrode is provided on the upper substrate (first substrate) side, and the reference electrode and the scan electrode are provided on the lower substrate (second substrate) side. Explained the case. However, the present invention is not limited to this, and the signal electrode is installed inside the display space so as to come into contact with the polar liquid, and the reference is made while being electrically insulated from the polar liquid. What is necessary is just to provide an electrode and a scanning electrode in one side of the 1st and 2nd board | substrate. Specifically, for example, the signal electrode may be provided on the second substrate side or on the rib, and the reference electrode and the scan electrode may be provided on the first substrate side.

In the description of each of the second and third embodiments, the case where the reference electrode and the scanning electrode are provided on the effective display area side and the ineffective display area side has been described. However, the present invention is limited to this. Instead, the reference electrode and the scanning electrode may be provided on the non-effective display area side and the effective display area side, respectively.

In the description of each of the second and third embodiments, the case where the reference electrode and the scanning electrode are provided on the display surface side surface of the lower substrate (second substrate) has been described. The reference electrode and the scan electrode embedded in the second substrate made of an insulating material can be used without limitation. In such a configuration, the second substrate can be used as a dielectric layer, and the installation of the dielectric layer can be omitted.

In the description of each of the second and third embodiments, the case where the reference electrode and the scan electrode are configured using a transparent electrode material has been described. However, the present invention relates to the pixel of the reference electrode and the scan electrode. Only one electrode placed so as to face the effective display area may be made of a transparent electrode material, and the other electrode not facing the effective display area may be opaque such as aluminum, silver, chromium, or other metal. Any electrode material can be used.

In the description of each of the second and third embodiments, the case where the belt-like reference electrode and the scan electrode are used has been described. However, the shapes of the reference electrode and the scan electrode of the present invention are not limited to this. For example, in a reflective display element in which the use efficiency of light used for information display is lower than that of a transmissive type, the shape may be such that light loss such as a line shape or a net shape hardly occurs.

In the description of each of the second and third embodiments, the case where a linear wiring is used for the signal electrode has been described. However, the signal electrode of the present invention is not limited to this, and a network wiring or the like is used. Wirings formed in other shapes can also be used.

In the description of each of the second and third embodiments, the case where the color filter layer is formed on the surface on the non-display surface side of the upper substrate (first substrate) has been described. However, the present invention is not limited to this. Instead, the color filter layer can be provided on the surface of the first substrate on the display surface side or on the lower substrate (second substrate) side. Thus, the case where the color filter layer is used is preferable in that a display element which is easy to manufacture can be easily configured as compared with the case where a plurality of colors of polar liquids are prepared. In addition, the color filter part (opening part) and the black matrix part (light-shielding film) included in the color filter layer appropriately and reliably provide an effective display area and an ineffective display area with respect to the display space. It is also preferable in that it can be set.

In the description of each of the first to third embodiments, the size of the dummy region is determined based on the amount of polar liquid and oil (insulating fluid) sealed in each of the plurality of pixel regions. However, the present invention is not limited to this, and the size of the dummy region can be appropriately changed according to the type of polar liquid, the type of insulating fluid, and the like.

In the description of each of the first to third embodiments, after the oil or polar liquid is sealed and the upper substrate (first substrate) and the lower substrate (second substrate) are bonded together, capillary action is performed. However, the present invention is not limited to this, and after the oil or polar liquid is sealed, the first substrate and the second substrate are bonded together. Prior to this, polar liquid or oil may be sealed using a dispenser method, an ink jet method, or the like. Further, the polar liquid and the oil may be sealed at the same time before the first substrate and the second substrate are bonded to each other.

The present invention is useful for a display element that can prevent display quality from being deteriorated, a manufacturing method thereof, and an electric device using the display element.

1 Image display device (electric equipment)
2, 2 'display element 6 Upper substrate (first substrate)
7 Lower substrate (second substrate)
8 Pixel electrode (second electrode)
9 Common electrode (first electrode)
10 Color filter layer 10r, 10g, 10b Color filter part (opening part)
10s black matrix (light shielding film)
11, 34 Rib 11a First rib member 11b Second rib member 12, 12 ′ Polar liquid (predetermined liquid)
13, 13 'oil (insulating fluid, predetermined liquid)
14 Dielectric layer (capacitor)
18 Signal electrode (first electrode)
19 Reference electrode (second electrode)
20 Scanning electrode (second electrode)
21 Signal driver (Signal voltage application unit)
22 Reference driver (reference voltage application unit)
23 Scanning driver (scanning voltage application unit)
25 Color filter layer 25r, 25g, 25b Color filter part (opening)
25s black matrix (light shielding film)
S source wiring (data wiring)
G Gate wiring SW Thin film transistor (switching element)
K display space P pixel area P1 effective display area P2 ineffective display area DP dummy pixel area (dummy area)
DA dummy area ED Effective display area ND Non-effective display area

Claims (17)

1. A second substrate provided on the non-display surface side of the first substrate so that a predetermined display space is formed between the first substrate provided on the display surface side and the first substrate. An effective display area and an ineffective display area set with respect to the display space, and a polar liquid sealed so as to be movable at least toward the effective display area inside the display space. A display element configured to change the display color on the display surface side by moving the polar liquid,
   A first electrode installed in the display space so as to be in contact with the polar liquid; and the first and second electrodes in a state of being electrically insulated from the polar liquid and the first electrode. A second electrode provided on one side of the second substrate;
   An effective display unit having a plurality of pixel regions provided so as to divide the display space by ribs and an ineffective display unit provided to surround the effective display unit are set on the display surface. And
   Encapsulating the polar liquid and an insulating fluid that does not mix with the polar liquid inside each of the plurality of pixel regions in the effective display unit,
   A dummy area is provided between the first and second substrates corresponding to the ineffective display portion, and a predetermined liquid is sealed inside the dummy area.
   A display element characterized by the above.
2. The display element according to claim 1, wherein the polar liquid and the insulating fluid are used as the predetermined liquid.
3. The display element according to claim 1, wherein the non-effective display unit is set by a light shielding film provided on at least one side of the first and second substrates.
4. The display element according to any one of claims 1 to 3, wherein the dummy region is partitioned by a rib in a shape different from that of the pixel region.
5. Data wiring and gate wiring are provided in a matrix on one side of the first and second substrates,
   On the other side of the first and second substrates, a planar transparent electrode as the first electrode is provided,
   Each of the plurality of pixel regions is provided in an intersection unit between the data line and the gate line,
   In each of the plurality of pixel regions, a switching element connected to the data wiring and the gate wiring, a pixel electrode as the second electrode connected to the switching element, and a charge supplied to the pixel electrode The display element according to any one of claims 1 to 4, further comprising a capacitor for holding.
6. The display element according to claim 5, wherein a dielectric layer provided on one side of the first and second substrates is used as the capacitor so as to cover the pixel electrode.
7. As the first electrode, a signal electrode installed inside the display space is used,
   As the second electrode, a reference electrode provided on one side of the first and second substrates so as to be installed on one side of the effective display area and the non-effective display area, and the effective display area Scanning electrode provided on one side of the first and second substrates in a state of being electrically insulated from the reference electrode so as to be installed on the other side of the side and the ineffective display area side The display element according to any one of claims 1 to 4, wherein is used.
8. A plurality of the signal electrodes are provided along a predetermined arrangement direction,
   The plurality of reference electrodes and the plurality of scanning electrodes are provided alternately with each other and intersect with the plurality of signal electrodes,
   A signal voltage applying unit that is connected to the plurality of signal electrodes and applies a signal voltage within a predetermined voltage range to each of the plurality of signal electrodes in accordance with information displayed on the display surface side; ,
   A selection voltage that is connected to the plurality of reference electrodes and that allows the polar liquid to move within the display space in response to the signal voltage for each of the plurality of reference electrodes; A reference voltage applying unit for applying one of a non-selection voltage for preventing the polar liquid from moving inside the display space;
   A selection voltage that is connected to the plurality of scan electrodes and that allows the polar liquid to move within the display space in response to the signal voltage for each of the plurality of scan electrodes; The display element according to claim 7, further comprising: a scanning voltage applying unit that applies one voltage of a non-selection voltage that prevents the polar liquid from moving inside the display space.
9. The display element according to claim 8, wherein each of the plurality of pixel regions is provided in a unit of intersection of the signal electrode and the scan electrode.
10. 10. The display element according to claim 6, wherein a dielectric layer is laminated on the surfaces of the reference electrode and the scanning electrode.
11. The display element according to any one of claims 1 to 10, wherein the plurality of pixel regions are provided in accordance with a plurality of colors capable of full color display on the display surface side.
12. The ineffective display area is set by a light shielding film provided on either one of the first and second substrates,
    12. The display element according to claim 1, wherein the effective display area is set by an opening formed in the light shielding film.
13. The display element according to claim 12, wherein the non-effective display portion and the non-effective display area are set by the same light shielding film provided on the first substrate side.
14. An electrical device having a display unit for displaying information including characters and images,
    14. An electric device using the display element according to claim 1 for the display portion.
15. A second substrate provided on the non-display surface side of the first substrate so that a predetermined display space is formed between the first substrate provided on the display surface side and the first substrate. An effective display area and an ineffective display area set with respect to the display space, and a polar liquid sealed so as to be movable at least toward the effective display area inside the display space. A method of manufacturing a display element configured to change the display color on the display surface side by moving the polar liquid,
    By setting a rib on one side of the first and second substrates, a plurality of pixel areas are set in the effective display area, and a dummy area is set in the ineffective display area surrounding the effective display area. Process,
    Encapsulating at least one of the polar liquid and an insulating fluid that does not mix with the polar liquid in each of the plurality of pixel regions and enclosing a predetermined liquid in the dummy region Process,
    A method for manufacturing a display element, comprising:
16. In the sealing step, a first sealing step of sealing the predetermined liquid with respect to the inside of the dummy region,
    16. The second enclosing step of enclosing at least one of the polar liquid and the insulating fluid into the inside of each of the plurality of pixel regions after the first enclosing step is included. The manufacturing method of the display element of description.
17. The method for manufacturing a display element according to claim 15, wherein the polar liquid and the insulating fluid are used as the predetermined liquid.

Images