CN110082980B - Reflective color electrophoretic display device - Google Patents

Reflective color electrophoretic display device Download PDF

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Publication number
CN110082980B
CN110082980B CN201810057298.8A CN201810057298A CN110082980B CN 110082980 B CN110082980 B CN 110082980B CN 201810057298 A CN201810057298 A CN 201810057298A CN 110082980 B CN110082980 B CN 110082980B
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China
Prior art keywords
display device
ink layer
electronic ink
sub
electrophoretic display
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CN201810057298.8A
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Chinese (zh)
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CN110082980A (en
Inventor
骆伯远
李岱原
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E Ink Holdings Inc
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E Ink Holdings Inc
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    • GPHYSICS
    • G02OPTICS
    • G02FOPTICAL DEVICES OR ARRANGEMENTS FOR THE CONTROL OF LIGHT BY MODIFICATION OF THE OPTICAL PROPERTIES OF THE MEDIA OF THE ELEMENTS INVOLVED THEREIN; NON-LINEAR OPTICS; FREQUENCY-CHANGING OF LIGHT; OPTICAL LOGIC ELEMENTS; OPTICAL ANALOGUE/DIGITAL CONVERTERS
    • G02F1/00Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics
    • G02F1/01Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour 
    • G02F1/165Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour  based on translational movement of particles in a fluid under the influence of an applied field
    • G02F1/166Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour  based on translational movement of particles in a fluid under the influence of an applied field characterised by the electro-optical or magneto-optical effect
    • G02F1/167Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour  based on translational movement of particles in a fluid under the influence of an applied field characterised by the electro-optical or magneto-optical effect by electrophoresis
    • GPHYSICS
    • G02OPTICS
    • G02FOPTICAL DEVICES OR ARRANGEMENTS FOR THE CONTROL OF LIGHT BY MODIFICATION OF THE OPTICAL PROPERTIES OF THE MEDIA OF THE ELEMENTS INVOLVED THEREIN; NON-LINEAR OPTICS; FREQUENCY-CHANGING OF LIGHT; OPTICAL LOGIC ELEMENTS; OPTICAL ANALOGUE/DIGITAL CONVERTERS
    • G02F1/00Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics
    • G02F1/01Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour 
    • G02F1/165Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour  based on translational movement of particles in a fluid under the influence of an applied field
    • G02F1/1675Constructional details
    • G02F1/1676Electrodes

Abstract

The invention discloses a reflective color electrophoretic display device, comprising: the pixel structure comprises a plurality of sub-pixel structures, wherein each sub-pixel structure comprises a columnar body, an electronic ink layer, two electrodes and a rotation control unit. The column comprises at least one partition arranged radially to divide the column into at least two sections. The electronic ink layer is positioned over one of the at least two portions of the columnar body, the electronic ink layer including two different colored particles. The two electrodes are electrically connected with the electronic ink layer to control the movement of the two different color particles. The rotation control unit is used for controlling the rotation of the columnar body. The color displayed by the sub-pixel structure can be controlled by controlling the rotation of the columnar body through the rotation control unit and controlling the color development of the electronic ink layer through the driving of the two electrodes. The method of controlling the size of the display area through mechanical and electrode driving can maintain the resolution of the display device and make the color expression better.

Description

Reflective color electrophoretic display device
Technical Field
The invention relates to a reflective color electrophoretic display device.
Background
The conventional reflective color electrophoretic display device is driven by a thin film transistor to display colors. However, the color representation is poor due to the small size of the sub-pixel structure. If the size of the sub-pixel structure is increased, more light can be reflected, and the color performance is better. However, the size of the sub-pixel structure is limited by the requirement of resolution, and cannot be infinitely enlarged, so that the color expression is limited.
Disclosure of Invention
The invention provides a reflective color electrophoretic display device, which comprises a plurality of sub-pixel structures, wherein each sub-pixel structure comprises a columnar body, an electronic ink layer, two electrodes and a rotation control unit. The color displayed by the sub-pixel structure can be controlled by controlling the rotation of the columnar body through the rotation control unit and controlling the color development of the electronic ink layer through the driving of the two electrodes. The method of controlling the size of the display area through mechanical and electrode driving can maintain the resolution of the display device and make the color expression better.
The invention provides a reflective color electrophoretic display device, comprising: the pixel structure comprises a plurality of sub-pixel structures, wherein each sub-pixel structure comprises a columnar body, an electronic ink layer, two electrodes and a rotation control unit. The column comprises at least one partition arranged radially to divide the column into at least two sections. The electronic ink layer is positioned over one of the at least two portions of the columnar body, the electronic ink layer including two different colored particles. The two electrodes are electrically connected with the electronic ink layer to control the movement of the two different color particles. The rotation control unit is used for controlling the rotation of the columnar body.
According to embodiments of the present invention, the two electrodes are an upper electrode and a lower electrode, respectively, the upper electrode contacts the upper surface of the electronic ink layer, and the lower electrode contacts the lower surface of the electronic ink layer and is interposed between the electronic ink layer and at least two portions of the pillar.
According to various embodiments of the present invention, the sub-pixel structure further comprises an insulator adjacent to the electronic ink layer.
According to various embodiments of the present invention, a rotational control unit includes a shaft located within a cylinder; and a first signal line electrically connected to the shaft for controlling the rotation of the cylindrical body.
According to various embodiments of the present invention, the sub-pixel structure further comprises: the second signal line and the third signal line are respectively electrically connected with the two electrodes.
According to various embodiments of the present invention, one of the second signal line and the third signal line is disposed above the spacer.
According to various embodiments of the present invention, the diameter of the sub-pixel structure is between 5 mm and 500 mm.
According to various embodiments of the present invention, the column contains three partitions to divide the column into three sections.
According to embodiments of the present invention, the sub-pixel structure further comprises a reflective coating layer over another of the at least two portions of the pillars.
According to embodiments of the present invention, the color of the two differently colored particles of the electronic ink layer is selected from the group consisting of: red, green, blue, white, cyan, magenta, yellow, and black.
According to various embodiments of the present invention, the two different color particles of the electronic ink layer are respectively black and white, and the sub-pixel structure further includes a color filter disposed above the upper electrode.
Compared with the prior art, the reflective color electrophoretic display device has the advantages that the resolution of the display device can be maintained by controlling the size of the display area through mechanical and electrode driving, and the color performance can be better.
Drawings
The above and other objects, features, and advantages of the present invention will become more apparent from the following description of the embodiments taken in conjunction with the accompanying drawings in which:
FIG. 1 is a schematic top view of a reflective color electrophoretic display device according to various embodiments of the present invention.
FIG. 2 is a schematic cross-sectional view illustrating sub-pixel structures of a reflective color electrophoretic display device according to various embodiments of the invention.
FIG. 3 is a schematic cross-sectional view illustrating sub-pixel structures of a reflective color electrophoretic display device according to various embodiments of the invention.
FIG. 4 is a schematic cross-sectional view illustrating a sub-pixel structure of a reflective color electrophoretic display device according to embodiments of the present invention.
Detailed Description
The following provides many different embodiments or examples of the invention to achieve different technical features of the provided subject matter. The elements and designs of the following specific examples are provided to simplify the present disclosure. These are, of course, merely examples and are not intended to be limiting. For example, the description discloses forming a first feature over a second feature, including embodiments in which the first feature and the second feature are formed in direct contact, as well as embodiments in which additional features are formed between the first feature and the second feature, i.e., the first feature and the second feature are not in direct contact. Moreover, repeated reference symbols and/or verbs may be used in various examples. These repeated symbols or words are provided for simplicity and clarity and are not intended to limit the relationship between the various embodiments and/or the described structures.
Furthermore, spatially relative terms, such as "lower," "upper," and the like, are used for convenience in describing the relative relationship of one element or feature to another element or feature in the figures. These spatially relative terms are intended to encompass different orientations of the device in use or operation in addition to the orientation depicted in the figures. The device may be otherwise oriented (e.g., rotated 90 degrees or at other orientations) and the spatially relative descriptors used herein interpreted accordingly.
The present invention provides a reflective color electrophoretic display device, which comprises a plurality of sub-pixel structures, wherein each sub-pixel structure comprises a column, an electronic ink layer, two electrodes and a rotation control unit. The color displayed by the sub-pixel structure can be controlled by controlling the rotation of the columnar body through the rotation control unit and controlling the color development of the electronic ink layer through the driving of the two electrodes. The method of controlling the size of the display area through mechanical and electrode driving can maintain the resolution of the display device and make the color expression better.
FIG. 1 is a schematic top view of a reflective color electrophoretic display device according to various embodiments of the present invention. As shown in fig. 1, the reflective color electrophoretic display device includes a plurality of sub-pixel structures 100. The plurality of sub-pixel structures 100 may be arranged in a pixel array.
FIG. 2 is a schematic cross-sectional view illustrating sub-pixel structures of a reflective color electrophoretic display device according to various embodiments of the invention. Referring to fig. 1 and 2, the sub-pixel structure 100 includes a pillar 110, an electronic ink layer 120, two electrodes 130 and 140, and a rotation control unit 180. In some embodiments, as shown in fig. 2, the diameter d1 of the sub-pixel structure 100 is between 5 mm and 500 mm. The diameter d1 of the sub-pixel structure 100 may be determined according to the application of the reflective color electrophoretic display device, such as a personal display device or an advertisement board.
As shown in fig. 2, the cylinder 110 includes at least one partition 112 radially disposed to divide the cylinder 110 into at least two portions 110a, 110 b. In some embodiments, the column 110 includes two baffles 112 radially disposed to separate the column 110 into two portions 110a, 110 b. In some embodiments, the spacer 112 comprises an insulating material or other suitable material. The radii of the portions separated by the partition 112 may be the same or different. In some embodiments, as shown in FIG. 2, the two portions 110a, 110b separated by the partition 112 have different radii.
The electronic ink layer 120 is located over one 110a of the two portions 110a, 110b of the pillar 110. The electronic ink layer 120 includes two different colored particles 122, 124. In some embodiments, the color of the two differently colored particles 122, 124 of the electronic ink layer 120 is selected from the group consisting of: red, green, blue, white, cyan, magenta, yellow, and black. These color particles 122, 124 are charged.
The two electrodes 130, 140 are electrically connected to the electronic ink layer 120 to control the movement of the two different color particles 122, 124. In some embodiments, the two electrodes 130, 140 are the upper electrode 130 and the lower electrode 140, respectively, and the electronic ink layer 120 is disposed between the upper electrode 130 and the lower electrode 140. The upper electrode 130 contacts the upper surface of the electronic ink layer 120. The lower electrode 140 contacts the lower surface of the electronic ink layer 120, and the lower electrode 140 is interposed between the electronic ink layer 120 and the portion 110a of the columnar body 110.
As shown in fig. 2, in some embodiments, the sub-pixel structure further includes a second signal line 172 and a third signal line 174 electrically connected to the two electrodes 130 and 140, respectively. In some embodiments, one of the second signal line 172 and the third signal line 174 is disposed above the spacer 112. In some embodiments, as shown in fig. 2, the second signal line 172 and the third signal line 174 are disposed above the spacer 112. In some embodiments, the second signal line 172 and the third signal line 174 are disposed along a radial direction of the pillar 110. In some embodiments, different signals may be transmitted to the second signal line 172 and the third signal line 174 through the signal lines inside the shaft 182, and then to the upper electrode 130 and the lower electrode 140, respectively, to control the electric field of the electronic ink layer 120, and thus the movement of the charged color particles 122, 124.
As shown in fig. 2, in some embodiments, the third signal line 174 directly contacts the lower electrode 140. In some embodiments, the sub-pixel structure further includes a conductor 160, such that the upper electrode 130 can be electrically connected to the second signal line 172 through the conductor 160. In some embodiments, the conductor 160 is a conductive glue or wire. In some embodiments, the conductor 160 is silver paste. In other embodiments, the second signal line 172 may directly contact the upper electrode 130.
As shown in fig. 2, in some embodiments, the sub-pixel structure 100 further comprises an insulator 152 adjacent to the electronic ink layer 120. In some embodiments, the sub-pixel structure 100 further comprises an insulator 154 adjacent to the lower electrode 140. The insulators 152 and 154 are used to electrically isolate the upper electrode 130, the conductor 160, the second signal line 172, and the lower electrode 140, which are electrically connected to each other. In other embodiments, other insulating structures may be used instead of the insulators 152 and 154 to electrically isolate the upper electrode 130, the conductor 160, the second signal line 172, and the lower electrode 140, which are electrically connected to each other.
As shown in fig. 1, the rotation control unit 180 is used to control the rotation of the column 110. In detail, the rotation control unit 180 can be used to control the rotation angle of the pillar 110 to control the color displayed by the sub-pixel structure 100. In some embodiments, as shown in fig. 1 and 2, the rotation control unit 180 includes a shaft 182 and a first signal line 184. The shaft 182 is disposed inside the column 110, and the first signal line 184 is electrically connected to the shaft 182 to control the rotation angle of the column 110. In some embodiments, shaft 182 extends through cylindrical body 110.
As shown in fig. 2, in some embodiments, the sub-pixel structure 100 further comprises a reflective paint layer 190 over the other 110b of the at least two portions 110a, 110b of the pillar 110. In some embodiments, the reflective coating layer 190 comprises a resin material or other suitable material. In some embodiments, the color of the reflective paint layer 190 is red, green, blue, white, cyan, magenta, yellow, and black. In some embodiments, the color of the reflective paint layer 190 is different from the color of the two chromatic particles 122, 124.
In other embodiments, there is no reflective coating layer over the portion 110b of the pillar 110 of the sub-pixel structure 100, and the upper surface of the portion 110b of the pillar 110 is directly exposed. In some embodiments, the portion 110b of the pillar 110 of the sub-pixel structure 100 is white, black, or other color.
As can be seen from the above, the sub-pixel structure 100 shown in FIG. 2 can display three colors. By controlling the rotation angle of the pillar 110, the color displayed by the pixel structure 100 can be controlled.
FIG. 3 is a schematic cross-sectional view illustrating sub-pixel structures of a reflective color electrophoretic display device according to various embodiments of the invention. The difference between fig. 3 and fig. 2 is that the column 110 of fig. 3 includes three partitions 112 to separate the column 110 into three portions 110a, 110b, 110 c. The embodiment of the structure above the portions 110a and 110b of the column 110 can refer to the embodiment of the structure above the portions 110a and 110b of the column 110 in fig. 2, and is not repeated herein.
An example of a structure above portion 110c of column 110 can be found in reference to an example of a structure above portion 110a of column 110 of fig. 2. It is noted that the electronic ink layer 120 is disposed over the portion 110c of the pillar 110, and includes two different color particles 126, 128. In some embodiments, the color of the chromatic particles 126, 128 is different than the color of the chromatic particles 122, 124. In this way, the sub-pixel structure 100 shown in fig. 3 can display five colors. By controlling the rotation angle of the pillar 110, the color displayed by the pixel structure 100 can be controlled.
It is understood that in other embodiments, the pillar may be divided into more than four portions, and an electronic ink layer and an electrode may be selectively disposed on each portion, or a reflective coating layer may be disposed on each portion, so that the sub-pixel structure can display more than one color.
FIG. 4 is a schematic cross-sectional view illustrating sub-pixel structures of a reflective color electrophoretic display device according to various embodiments of the invention. In some embodiments, as shown in fig. 4, the color particles 122 and 124 of the electronic ink layer 120 are black and white, respectively. In some embodiments, the sub-pixel structure 100 further comprises a color filter 195 over the upper electrode 130. In some embodiments, the color filter 195 comprises a color photoresist, such as red, green, blue, cyan, magenta, yellow photoresist. In some embodiments, the color filter 195 comprises red, green, and blue photoresists. In some embodiments, the color filter 195 includes cyan, magenta, and yellow photoresists. In other embodiments, color filters (not shown) may be disposed above the two upper electrodes 130 of fig. 3, respectively.
The foregoing briefly addresses the features of the various embodiments so that those skilled in the art may better understand the aspects of the present invention. Those skilled in the art should appreciate that they may readily use the present invention as a basis for designing or modifying other processes and structures for carrying out the same purposes and/or achieving the same advantages of the embodiments introduced herein. Those skilled in the art should also realize that such equivalent constructions do not depart from the spirit and scope of the present disclosure, and that they may make various changes, substitutions, and alterations herein without departing from the spirit and scope of the present disclosure.

Claims (11)

1. A reflective color electrophoretic display device, comprising:
a plurality of sub-pixel structures, each of the sub-pixel structures comprising:
a cylindrical body including at least one partition plate radially disposed to divide the cylindrical body into at least two parts;
an electronic ink layer over one of the at least two portions of the pillars, the electronic ink layer comprising two different color particles;
two electrodes electrically connected to the electronic ink layer to control the movement of the two different color particles; and
and a rotation control unit for controlling the rotation of the columnar body.
2. The reflective color electrophoretic display device according to claim 1, wherein the two electrodes are an upper electrode and a lower electrode, respectively, the upper electrode contacting an upper surface of the electronic ink layer, the lower electrode contacting a lower surface of the electronic ink layer and being interposed between the electronic ink layer and the one of the at least two portions of the pillar.
3. The reflective color electrophoretic display device of claim 1, wherein the sub-pixel structure further comprises:
an insulator adjacent the electronic ink layer.
4. The reflective color electrophoretic display device of claim 1, wherein the rotation control unit comprises:
a shaft located within the cylinder; and
the first signal wire is electrically connected with the shaft rod so as to control the rotation of the columnar body.
5. The reflective color electrophoretic display device of claim 1, wherein the sub-pixel structure further comprises:
and the second signal wire and the third signal wire are respectively and electrically connected with the two electrodes.
6. The reflective color electrophoretic display device according to claim 5, wherein one of the second signal line and the third signal line is disposed above the partition.
7. The reflective color electrophoretic display device of claim 1, wherein the diameter of the sub-pixel structure is between 5 mm and 500 mm.
8. The reflective color electrophoretic display device of claim 1, wherein the pillar comprises three partitions to divide the pillar into three portions.
9. The reflective color electrophoretic display device of claim 1, wherein the sub-pixel structure further comprises:
a reflective coating layer located over another of the at least two portions of the cylinder.
10. The reflective color electrophoretic display device according to claim 1, wherein the two differently colored particles of the electronic ink layer are selected from the group consisting of: red, green, blue, white, cyan, magenta, yellow, and black.
11. The reflective color electrophoretic display device according to claim 2, wherein the two different color particles of the electronic ink layer are respectively black and white, and the sub-pixel structure further comprises:
and the color filter is positioned above the upper electrode.
CN201810057298.8A 2018-01-22 2018-01-22 Reflective color electrophoretic display device Active CN110082980B (en)

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Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2000122102A (en) * 1998-10-16 2000-04-28 Sony Corp Display device
TW200521545A (en) * 2003-11-12 2005-07-01 Lg Philips Lcd Co Ltd Reflective type liquid crystal display device and fabricating method thereof
CN105378554A (en) * 2013-05-14 2016-03-02 伊英克公司 Colored electrophoretic displays
CN106990638A (en) * 2017-05-05 2017-07-28 大连龙宁科技有限公司 A kind of high-contrast electrophoresis type display device

Family Cites Families (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2016057587A (en) * 2014-09-12 2016-04-21 富士フイルム株式会社 Reflection type display device

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2000122102A (en) * 1998-10-16 2000-04-28 Sony Corp Display device
TW200521545A (en) * 2003-11-12 2005-07-01 Lg Philips Lcd Co Ltd Reflective type liquid crystal display device and fabricating method thereof
CN105378554A (en) * 2013-05-14 2016-03-02 伊英克公司 Colored electrophoretic displays
CN106990638A (en) * 2017-05-05 2017-07-28 大连龙宁科技有限公司 A kind of high-contrast electrophoresis type display device

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