JP6048570B2 - Display device - Google Patents

Description

  The present invention relates to a display device, and more particularly, to a display device capable of color display by pressure generation means such as a piezoelectric element and inflow of a colored liquid into a pixel space.

  In recent years, various types of display devices have been developed as display media that replace paper. For example, a microcapsule electronic paper or the like has been put to practical use as a black and white display device, but no display device having sufficient practicality has been obtained to date.

One of the methods for colorization is a liquid crystal method, for example, a reflective display device (Patent Document 1). In this liquid crystal reflective display device, a front substrate provided with a plurality of color filters, a transparent counter electrode, and a liquid crystal alignment film, a rear substrate disposed so as to face the front substrate, and the front substrate and the rear surface And a liquid crystal layer provided between the substrate and the substrate. The back substrate has an interlayer insulating layer, a reflective layer, and an alignment layer formed on a TFT substrate having a plurality of switching elements. The interlayer insulating layer has a surface shape exhibiting retroreflectivity. Since the reflective layer is formed on the interlayer insulating layer and has irregularities reflecting the surface shape of the interlayer insulating layer, it functions as a retroreflector. The reflective layer is also composed of a plurality of pixel electrodes that are spaced apart from each other as a unit of image display. Each pixel electrode in the reflective layer is connected to the drain electrode of the corresponding switching element through a contact portion formed in the interlayer insulating layer.
In this reflective display device, the liquid crystal layer has, for example, a transmission state that transmits light and a scattering state that scatters light (forward scattering) by changing a voltage applied between the counter electrode and each pixel electrode. Can be switched between.

JP 2008-40513 A

  In the conventional liquid crystal display device as described above, incident light is reflected by a color filter, a transparent counter electrode on the front substrate, a liquid crystal layer provided between the front substrate and the rear substrate, and a reflective layer on the rear substrate. Since this reflected light is used for display, color developability and visibility are poor, and in particular, a configuration is adopted in which three reflected lights are combined by overlapping color filters of the three primary colors of light (RGB) in order to produce white. However, there is a problem that the reflectance is further lowered and the screen becomes dark.

  The present invention has been made in view of such circumstances, and an object thereof is to provide a display device that is excellent in color development and visibility.

To achieve the above object, a display device of the present invention has a surface which is defined by the transparent substrate, a multi-compartment pixel space in the direction parallel or perpendicular to the plane of the transparent substrate, wherein the pixel space communicated with the pixel space on the opposite side to the transparent substrate in a colored colored liquid storable liquid storage space, the first pressure generating means for applying a pressure variation to the liquid storage space, said transparent An achromatic or transparent liquid that communicates with the pixel space in a second direction that intersects the first direction in which the substrate, the pixel space, and the liquid storage space are arranged and extends in the first direction. And a second pressure generating means for applying pressure fluctuation in the escape portion, and the colored liquid stored in the liquid storage space is driven by the first pressure generating means. Into the pixel space , If the colored liquid to flow into the pixel space, when said achromatic or clear liquid flows into the relief space, and side view of the relief portion from the second direction, and the clearance portion The liquid storage space has an overlapping portion, and the colored liquid that has flowed into the pixel space can be visually recognized through the transparent substrate.

  According to the above configuration, the colored liquid stored in the liquid storage space is caused to flow into the pixel space by driving the pressure generating means, so that one pixel space can be a pixel that displays the color of the colored liquid. The color of the colored liquid can be visually recognized from the outside through the transparent substrate. As a result, the pixel space can be displayed in color by arranging a plurality of pixel spaces in the surface direction of the transparent substrate or in the direction perpendicular to the surface, and the color development and visibility can be achieved by using the reflected light on the transparent substrate. An excellent display device can be obtained.

  Further, the display device of the present invention is characterized in that the gradation of the color is expressed by controlling the pressure generating means and controlling the amount of the colored liquid in the pixel space.

  According to the above configuration, the color gradation can be changed by controlling the pressure generating means and controlling the amount of the colored liquid in the pixel space.

  The display device of the present invention is characterized in that the surface of the pixel space opposite to the transparent substrate is achromatic.

  According to the above configuration, the surface on the side opposite to the transparent substrate in the pixel space is achromatic, so that black, white, or an intermediate color thereof can be displayed on the side opposite to the transparent substrate in the pixel space without controlling the colored liquid. The display color can be displayed, and the display device can be simplified.

Further, the display device of the present invention includes an achromatic color liquid enclosed in the pixel space, and a relief space into which the achromatic color liquid can flow. One of the achromatic color liquid and the colored liquid is oil-based. The other is water,
When the colored liquid flows into the pixel space, the achromatic liquid flows into the escape space.

  According to the above configuration, the achromatic color liquid is sealed in the pixel space, a relief space into which the achromatic color liquid can flow is formed, and one of the achromatic color liquid and the colored liquid is an oil system and the other is an aqueous system. Therefore, if the colored liquid flows into the pixel space without mixing the achromatic color liquid and the colored liquid, the achromatic color liquid can flow into the escape space. It is possible to reliably switch to non-display by.

  In addition, the display device of the present invention is characterized by comprising pressure generating means for applying pressure fluctuation in the escape space.

  According to the above configuration, by providing the pressure generating means for applying pressure fluctuation in the escape space, the achromatic liquid can be reliably introduced into the pixel space and recovered into the escape space by the pressure generating means. Switching between color display by coloring and non-display by achromatic color can be speeded up.

2A and 2B are a plan view and a cross-sectional view illustrating the principle of a display device. It is the top view and sectional drawing of the pixel of the display apparatus by parallel color mixing. It is the front view and partial enlarged view of a display apparatus. It is the top view and sectional drawing of the pixel of a display apparatus. It is the top view and sectional drawing of the pixel of a display apparatus. It is the top view and sectional drawing of a pixel of a display device by subtractive color mixture. It is a perspective view of a pixel of a display device.

DESCRIPTION OF EMBODIMENTS Hereinafter, embodiments for carrying out the present invention will be described with reference to the accompanying drawings. In the embodiment described below, a color display device that performs display in color will be described as an example of the display device of the present invention.
As shown in FIG. 1, a color display device (hereinafter simply referred to as a display device) 1 according to the present invention is configured such that one pixel 2 includes a pixel space 3, a liquid storage space 4, a pressure generating means 5, and the like. .

  The color display principle in one pixel 2 is that the colored liquid 6 stored in the liquid storage space 4 is caused to flow into the pixel space 3 by driving the pressure generating means 5, so that one pixel space 3 is the color of the colored liquid 6. The color 2 of the colored liquid 6 can be viewed from the outside (when ON), or the driving of the pressure generating means 5 is switched to return the colored liquid 6 to the liquid storage space 4 so that the pixel space 3 is displayed. This is performed by setting a non-colored state (when OFF) that is not colored.

  The display device 1 uses RGB, which is the three primary colors of light, or CMY, which is the three primary colors of the pigment. For example, as shown in FIG. 2, there are three pixels of the three primary colors of CMY and pixels that display black (K). A pixel unit 7 that mixes four pixels horizontally and mixes in parallel is configured to display a color. For example, as shown in FIG. 3, the display device 1 is configured using a pixel unit 7 in which four pixels are arranged in a rectangle.

  Each pixel 2 constituting such a parallel-mixed color pixel unit 7 has the same configuration. The pixel space 3 of the pixel 2 is configured such that one surface is partitioned by a transparent substrate 31, for example, the transparent substrate 31 is formed in a square shape, and the opposite side of the transparent substrate 31 is formed in a quadrangular pyramid surface 32. . A pixel unit 7 is configured by partitioning the transparent substrate 31 by arranging four pixel spaces 3 in the plane direction.

  In the pixel space 3, a liquid storage space 4 is formed through a communication path 33 that communicates with the center of the quadrangular pyramid surface 32, and the colored liquid 6 is stored in the liquid storage space 4. The surface of the liquid storage space 4 opposite to the communication passage 33 is formed of an elastic plate 41 so that the volume can be changed by bending. Then, by setting the liquid storage space 4 to the same or larger volume as the pixel space 3, the entire amount of the colored liquid 6 can be stored in the liquid storage space 4, and the transparent liquid 31 is caused to flow into the pixel space 3 by the transparent substrate 31. The color of the colored liquid 6 can be visually recognized from the outside.

  In the pixel unit 7 of the color mixture in parallel as the coloring liquid 6, four colors of CMY (C: cyan, M: magenta, Y: yellow) and black (K), which are the three primary colors of the pigment, are used. As a result, in the state where the colored liquid 6 is stored in the liquid storage space 4, the color of the surface 32 on the opposite side of the transparent substrate 31 in the pixel space 3 is visually recognized. An achromatic color such as intermediate gray can be identified as a non-colored state.

The liquid storage space 4 is provided with a pressure generating means 5 that applies a pressure fluctuation in the liquid storage chamber 4. As the pressure generating means 5, for example, a bending type piezoelectric element (piezo) is used, which is adhered to an elastic plate.
As a result, the colored liquid 6 stored in the liquid storage space 4 is caused to flow into the pixel space 3 by driving the piezoelectric element that is the pressure generating means 5, and one pixel space 3 displays the color of the colored liquid 6. As the pixel 2, the color of the colored liquid 6 can be viewed from the outside through the transparent substrate 31.

  Further, the colored liquid 6 is set as a translucent liquid, the piezoelectric element 51 constituting the pressure generating means 5 is controlled, the deformation amount of the elastic plate 41 is adjusted, and the amount of the colored fluid 6 in the pixel space 3 is controlled. Thus, the color gradation can be changed.

  By configuring the display device 1 as a pixel unit 7 by combining four such pixels 2, the color of the colored liquid 6 can be visually recognized through the transparent substrate 31, and color development is improved as compared with the liquid crystal method. Can be increased. In addition, the pixel 2 can be thinned, the display device 1 can be thinned, and the partition density of the pixels 2 can be increased to achieve high resolution.

  Next, another embodiment of the display device of the present invention will be described with reference to FIGS. In this display device 10, the colored liquid 6 of the pixel 2 is caused to flow into the pixel space 3, and the colored fluid 6 of the pixel space 3 is stored in the liquid storage space 4 to make the pixel space 3 uncolored. In order to ensure switching, the achromatic color liquid 11 is sealed in the pixel space 3 and an escape space 12 is provided in communication with the pixel space 3 and into which the achromatic color liquid 11 flows. One of the achromatic liquid 11 and the colored fluid 6 in the liquid storage space 4 is an oil-based liquid and the other is a water-based liquid that does not mix with each other. Thus, if the colored liquid 6 flows into the pixel space 3 by driving the piezoelectric element 51 constituting the pressure generating means 5 without mixing the achromatic color liquid 11 and the colored liquid 6, the achromatic color liquid 11 is changed. It is possible to flow into the escape space 12, and it is possible to surely switch between color display by coloring visually recognized through the transparent substrate 31 and non-display by achromatic color.

  In addition to the piezoelectric element 51 constituting the pressure generating means being attached to the elastic plate 41 of the liquid storage space 4, the side wall of the escape space 12 is formed by the elastic plate 121, and the pressure generating means is provided on the elastic plate 121. 13, for example, the pressure generating means 13 is composed of a piezoelectric element 131 and is affixed to the elastic plate 121, whereby pressure fluctuation can be applied to the escape space 12, whereby the achromatic liquid in the escape space 12 can be provided. 11 can flow into the pixel space 3. Note that a transparent liquid can be used in place of the achromatic liquid 11.

  Next, another embodiment of the display device of the present invention will be described with reference to FIGS. For example, as shown in FIG. 6, the display device 20 is configured to express a color by using a pixel unit 8 that subtracts and mixes three pixels 2 of the three primary colors of CMY sequentially from the transparent substrate 31 side. Is.

  Each pixel 2 constituting such a subtractive color mixing pixel unit 8 has the same configuration, and the pixel space 3 of the pixel 2 is partitioned on one side by a transparent substrate 31 and on the opposite side. Is also formed of a transparent substrate 34. For example, the transparent substrates 31 and 34 are formed in a square shape. A pixel unit 8 is configured by partitioning the transparent substrates 31 and 34 by overlapping three pixel spaces 3 in the vertical direction.

In the pixel space 3, as shown in FIG. 7, a liquid storage space 4 is formed orthogonal to the pixel space 3 via a communication path 33 that communicates with one end corner of the transparent substrate 34, and the liquid storage space 4 is halfway A transparent colored liquid 6 is stored. One side surface of the liquid storage space 4 is formed of an elastic plate 41 and is bent so that the volume can be changed.
In addition, the escape space 12 is formed on the opposite side of the liquid storage space 4 so as to communicate with the other end corner of the transparent substrate 34, and the achromatic liquid 11 sealed in the pixel space 3 is escaped. 12 can be made to flow in. One side of the escape space 12 is formed of an elastic plate 121 and is bent so that the volume can be changed.
A piezoelectric element 51 constituting the pressure generating means 5 is attached between the liquid storage space 4 and the escape space 12, and the piezoelectric element 51 applies pressure fluctuation to the elastic plate 41 of the liquid storage space 4, and The pressure variation opposite to that of the liquid storage space 4 can be applied to the elastic plate 121 of the escape space 12.

The pixel 2 in which the liquid storage space 4, the escape space 12 and the piezoelectric element 51 are arranged orthogonally along one side surface of the pixel space 3 is shifted by 90 degrees corresponding to each side of the quadrilateral, The pixel unit 8 is configured by overlapping the pixels 2, and the colored fluids of the three overlapped pixels can be mixed and visually recognized.
By setting the liquid storage space 4 to the same or larger volume as the pixel space 3, the entire amount of the colored liquid 6 can be stored in the liquid storage space 4, and by allowing the colored liquid 6 to flow into the pixel space 3, the transparent substrates 31 and 34. The color of the colored liquid 6 can be visually recognized from outside. A transparent liquid may be used in place of the achromatic liquid 11, and the escape space may be omitted, and only the liquid storage space may be provided to allow the colored fluid to flow into the pixel space 3.

In the subtractive color pixel unit 8 as the coloring liquid 6, a translucent liquid of CMY (C: cyan, M: magenta, Y: yellow) which is the three primary colors of the pigment is used. As a result, it is possible to visually recognize the mixed color of the colored liquid 6 that has flowed into the three superimposed pixel spaces through the transparent substrate 31 and the transparent substrate 34. For example, the black color can be obtained by mixing the three colors. It will be visually recognized.
Moreover, since all the colored liquids 6 are returned to the liquid storage space 4 and the color of the transparent substrate 34 of the lowermost pixel 2 is recognized, the transparent substrate 34 or a base disposed under the transparent substrate is recognized. By setting the color of the material to an achromatic color such as white or gray, the achromatic color can be visually recognized as a non-colored color.

  Further, the colored liquid 6 which is a translucent liquid is controlled by the piezoelectric element 51 constituting the pressure generating means 5, the deformation amount of the elastic plate 41 is adjusted, and the amount of the colored fluid 6 in the pixel space 3 is controlled. Thus, the color gradation can be changed.

  According to the display device 20 in which three such pixels 2 are stacked and combined to form the pixel unit 8, the color of the colored liquid 6 can be visually recognized in a mixed state through the transparent substrates 31 and 34. Compared to, color development can be improved. In addition, the pixel 2 can be thinned, the display device 20 can be thinned, and the partition density of the pixels 2 can be increased to achieve high resolution.

  In the present invention, each component such as a pixel shape and a pixel space shape is not limited to the above-described embodiment.

  DESCRIPTION OF SYMBOLS 1 ... Display apparatus, 2 ... Pixel, 3 ... Pixel space, 4 ... Liquid storage space, 5 ... Pressure generating means, 6 ... Colored liquid, 7 ... Pixel unit, 8 ... Pixel unit, 10 ... Display apparatus, 11 ... Achromatic Liquid, 12 ... escape space, 13 ... pressure generating means, 21 ... escape space, 31 ... transparent substrate, 32 ... opposite surface, 34 ... transparent substrate, 51 ... piezoelectric element.

Claims (2)

Has a surface which is defined by the transparent substrate, a multi-compartment pixel space in the direction parallel or perpendicular to the plane of the transparent substrate,
Said communicating with the pixel space, colored colored liquid storable liquid storage space on the opposite side to the transparent substrate in the pixel space,
A first pressure generating means for applying a pressure variation to the liquid storage space,
The transparent substrate, the pixel space, and the liquid storage space communicate with the pixel space in a second direction intersecting the first direction and extend in the first direction, and are achromatic or transparent. An escape portion capable of storing various liquids,
Second pressure generating means for applying pressure fluctuation in the escape portion;
With
The colored liquid stored in the liquid storage space flows into the pixel space by driving the first pressure generating unit,
If the colored liquid flows into the pixel space, the achromatic or transparent liquid flows into the escape space;
When the escape portion is viewed from the side in the second direction, the escape portion and the liquid storage space have overlapping portions,
The display device, wherein the colored liquid that has flowed into the pixel space is visible from the outside through the transparent substrate.   The display device according to claim 1, wherein the gradation of color is expressed by controlling the pressure generating unit and controlling an amount of the colored liquid in the pixel space.

Images