Display apparatus and method of manufacturing same

Abstract

The invention relates to a display device and a method of manufacturing the same. The display device includes: a light emitting element; a first electrode disposed on the light emitting element; an electronic ink layer including partition walls disposed on the first electrode, the partition walls including an internal space having a substantially recessed shape to accommodate electronic ink between the partition walls; a second electrode disposed on the electronic ink layer; and an adhesive layer disposed between the electronic ink layer and the second electrode and adhered to a surface of the electronic ink layer, and adjusting a viewing angle by moving carbon particles included in the electronic ink according to a voltage difference between the first electrode and the second electrode.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims priority to and the benefit of Korean Patent Application No. 10-2023-0142300 filed in the Korean Intellectual Property Office on October 23, 2023, the entire contents of which are incorporated herein by reference. Technical Field

[0003] The present disclosure relates to a display device and a method of manufacturing the display device. Background Art

[0004] The importance of display devices has increased with the development of multimedia. To this end, various types of display devices, such as an organic light emitting diode (OLED) display device and a liquid crystal display (LCD), are used.

[0005] A display device is a device that displays an image, and may include a display panel, such as an organic light emitting display panel or a liquid crystal display panel. Among them, an organic light emitting display panel (OLED panel) has attracted attention as a next-generation display device due to its advantages such as low voltage drive, light weight and thinness, wide viewing angle, and fast response speed. For example, research on a vehicle display device using an organic light emitting element is currently underway. Such a vehicle display device requires a display device and a method for manufacturing the display device, which can adjust the viewing angle by blocking external light that interferes with the passenger's field of vision in the case of night driving.

[0006] It should be understood that this background technology section is intended, in part, to provide a useful background for understanding the technology. However, this background technology section may also include ideas, concepts or understandings of parts that were not known or understood by a person skilled in the relevant art before the corresponding effective filing date of the subject matter disclosed herein. Summary of the invention

[0007] Embodiments provide a display device having improved efficiency by adjusting a viewing angle and a method of manufacturing the display device.

[0008] According to an embodiment of the present disclosure, a display device may include: a light-emitting element; a first electrode disposed on the light-emitting element; an electronic ink layer including a partition wall disposed on the first electrode, the partition wall including an internal space having a substantially concave shape to accommodate the electronic ink between the partition walls; a second electrode disposed on the electronic ink layer; and an adhesive layer disposed between the electronic ink layer and the second electrode and adhered to a surface of the electronic ink layer, and adjusting the viewing angle by moving carbon particles included in the electronic ink according to a voltage difference between the first electrode and the second electrode.

[0009] After a positive voltage is applied to the first electrode and a negative voltage is applied to the second electrode to move the carbon particles toward the first electrode, the binder layer may be adhered to an upper surface of the partition wall facing the second electrode.

[0010] The electronic ink layer may further include a base layer disposed on the first electrode to support the partition walls, and the partition walls may protrude from the base layer in a direction toward the second electrode and be spaced apart from each other on the base layer.

[0011] Each of the partition walls may have a first surface facing the base layer and a second surface opposite to the first surface and facing the second electrode, and a width of the first surface may be wider than or equal to a width of the second surface.

[0012] The first electrode and the second electrode may include indium tin oxide (ITO).

[0013] The partition wall and a solvent included in the electronic ink may have the same refractive index.

[0014] The partition wall may include resin.

[0015] The display device can operate in one of a viewing angle blocking mode and a wide viewing angle mode, and when the display device operates in the viewing angle blocking mode, the carbon particles can be dispersed and distributed in the internal space, and when the display device operates in the wide viewing angle mode, the carbon particles can be distributed near the first electrode.

[0016] The display device may operate in one of a viewing angle blocking mode and a wide viewing angle mode, and in a case where the display device operates in the wide viewing angle mode, a positive voltage may be applied to the first electrode and a negative voltage may be applied to the second electrode.

[0017] The display device may operate in one of a viewing angle blocking mode and a wide viewing angle mode, and in a case where the display device operates in the viewing angle blocking mode, a voltage pulse may be applied to the first electrode and the second electrode.

[0018] In the viewing angle blocking mode, in the case where a positive voltage is applied to the first electrode, a negative voltage may be applied to the second electrode, and in the case where a negative voltage is applied to the first electrode, a positive voltage may be applied to the second electrode.

[0019] Another aspect of the present disclosure relates to a method for manufacturing a display device. The method may include: forming a first electrode disposed on a light emitting element; forming an electronic ink layer on the first electrode that may include a partition wall, the partition wall including an inner space having a substantially concave shape to accommodate the electronic ink between the partition walls; forming a second electrode on the electronic ink layer; and forming an adhesive layer disposed between the electronic ink layer and the second electrode and adhered to a surface of the electronic ink layer.

[0020] In the method, forming the adhesive layer may include adhering the adhesive layer to a surface of the electronic ink layer after carbon particles included in the electronic ink move toward the first electrode due to a positive voltage applied to the first electrode and a negative voltage applied to the second electrode.

[0021] In the method, forming the electronic ink layer may include injecting the electronic ink into the inner space of the partition wall using liquid crystal dripping (ODF).

[0022] In the method, the electronic ink layer may further include a base layer disposed on the first electrode to support the partition walls, and the partition walls may protrude from the base layer in a direction toward the second electrode and be spaced apart from each other on the base layer.

[0023] In the method, the first electrode and the second electrode may include indium tin oxide (ITO).

[0024] In the method, the partition wall and a solvent included in the electronic ink may have the same refractive index.

[0025] In the method, the partition wall may include a resin.

[0026] The inner space of the partition wall may have a narrow lower end and a wide upper end.

[0027] The method may further include adjusting a viewing angle by moving carbon particles included in the electronic ink according to a voltage difference between the first electrode and the second electrode. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] The above and other features of the present disclosure will become more apparent by describing embodiments of the present disclosure in more detail with reference to the accompanying drawings, in which:

[0029] Figure 1 is a schematic perspective view schematically showing a display device according to an embodiment;

[0030] Figure 2 It is shown Figure 1 A block diagram of an embodiment of a display device;

[0031] Figure 3 It is along Figure 1 A schematic cross-sectional view taken along line II' of FIG.

[0032] Figure 4 It is shown Figure 3 A schematic cross-sectional view of an embodiment of an electronic ink layer;

[0033] Figure 5 It is shown Figure 3A schematic cross-sectional view of an embodiment of an electronic ink layer;

[0034] Figure 6 is a diagram showing a manufacturing step of a display device in which electronic ink is contained in Figure 4 A schematic cross-sectional view of a display device in a step of forming an electronic ink layer;

[0035] Figure 7 is a diagram showing a manufacturing step of a display device in which a second electrode and a window are provided Figure 6 A schematic cross-sectional view of a display device in a step of forming an electronic ink layer;

[0036] Figure 8 is shown operating in wide viewing mode Figure 1 A schematic cross-sectional view of an embodiment of a display device;

[0037] Fig. 9 is shown operating in view blocking mode Figure 1 A schematic cross-sectional view of an embodiment of a display device of ; and

[0038] Fig.10 is a flow chart illustrating an embodiment of a method of manufacturing a display device. DETAILED DESCRIPTION

[0039] Hereinafter, the embodiments are described in detail with reference to the accompanying drawings. It should be noted that in the following description, parts for understanding the operation according to the present disclosure are described, and the description of other parts may be omitted so as not to obscure the subject matter of the present disclosure. However, the present disclosure may be implemented in other forms and is not limited to the embodiments described herein. The embodiments described herein are provided to describe in detail so as to implement the technical spirit of the present disclosure to those skilled in the art to which the present disclosure belongs.

[0040] In the drawings, the size, thickness, ratio, and scale of elements may be exaggerated for convenience of description and clarity. The same reference numerals refer to the same elements throughout.

[0041] As used herein, the singular forms “a”, “an” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise.

[0042] In the specification and claims, for the purpose of its meaning and interpretation, the term "and / or" is intended to include any combination of the terms "and" and "or". For example, "A and / or B" may be understood to mean "A, B, or A and B". The terms "and" and "or" may be used in conjunction or disjunction and may be understood to be equivalent to "and / or".

[0043] In the specification and claims, for the purpose of its meaning and interpretation, the phrase "at least one of" is intended to include the meaning of "at least one selected from the group of..." For example, "at least one of A and B" can be understood to mean "A, B, or A and B".

[0044] It will be understood that although the terms first, second, etc. may be used herein to describe various elements, these elements should not be limited by these terms. These terms are only used to distinguish one element from another element. For example, without departing from the scope of the present disclosure, a first element may be referred to as a second element, and similarly, a second element may be referred to as a first element.

[0045] For ease of description, spatially relative terms "below," "below," "down," "above," "upper," etc. may be used herein to describe the relationship between one element or component and another element or component as shown in the drawings. It will be understood that, in addition to the orientation depicted in the drawings, spatially relative terms are intended to include different orientations of the device in use or operation. For example, in the case where the device shown in the drawings is flipped, a device located "below" or "below" another device may be placed "above" the other device. Thus, the illustrative term "below" may include both a lower position and an upper position. The device may also be oriented in other directions, and thus spatially relative terms may be interpreted differently depending on the orientation.

[0046] The term "overlap" or "overlapped" means that a first object can be above or below a second object, or on one side of the second object, and vice versa. Additionally, the term "overlap" may include layering, stacking, facing or facing, extending over, covering or partially covering, or any other suitable term as would be appreciated and understood by one of ordinary skill in the art.

[0047] The terms "face" and "facing" mean that the first element can be directly opposite to the second element or indirectly opposite to each other. In the case where a third element is inserted between the first element and the second element, the first element and the second element can be understood as being indirectly opposite to each other, but still facing each other.

[0048] When an element is described as “not overlapping” or “to not overlap” another element, this may include the elements being spaced apart, offset or separated from each other or any other suitable terminology as would be appreciated and understood by one of ordinary skill in the art.

[0049] When used in this specification, the terms “comprises,” “comprising,” “includes,” and / or “including,” “has,” “have,” and / or “having,” and variations thereof, specify the presence of stated features, integers, steps, operations, elements, components, and / or groups thereof, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and / or groups thereof.

[0050] The phrase "in a plan view" means that an object is viewed from the top, and the phrase "in a schematic sectional view" means that a vertically cut section of an object is viewed from the side.

[0051] As used herein, "about" or "approximately" is inclusive of the stated value and means within an acceptable range of deviation for the particular value as determined by one of ordinary skill in the art, in view of the measurements in question and the errors associated with the measurement of a particular quantity (i.e., the limitations of the measurement system). For example, "about" can mean within one or more standard deviations, or within ±30%, ±20%, ±10%, ±5% of the stated value.

[0052] Unless otherwise defined or implied herein, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by those of ordinary skill in the art to which the present disclosure belongs. It will also be understood that terms (such as those defined in commonly used dictionaries) should be interpreted as having a meaning consistent with their meaning in the context of the relevant art, and will not be interpreted in an idealized or overly formal sense unless explicitly defined as such herein.

[0053] It will be understood that when an element (or region, layer, portion, etc.) is referred to as being "on," "connected to" or "coupled to" another element in the specification, it can be directly disposed on, directly connected to or directly coupled to the other element described above, or intervening elements may be disposed between them.

[0054] It will be understood that the term "connected to" or "coupled to" may include a physical or electrical connection or both.

[0055] Figure 1 is a schematic perspective view schematically showing a display device according to an embodiment.

[0056] refer to Figure 1, the display device DD may include a display area DA and a non-display area NDA. The display area DA may be an area where an image is displayed, and the non-display area NDA may be disposed around the display area DA. The non-display area NDA is an area where no image is displayed. According to an embodiment, the shape of the display area DA and the shape of the non-display area NDA may be variously changed.

[0057] In the case where the display device DD is an electronic device in which the display surface is applied to a surface or onto a surface (such as a smart phone, a TV, a tablet PC, a mobile phone, a video phone, a car navigation system, an e-book reader, a desktop PC, a laptop PC, a netbook, a workstation, a server, a PDA, a portable multimedia player (PMP), an MP3 player, a medical device, a camera, or a wearable device), the present disclosure can be applied to the display device DD.

[0058] The display device DD may be provided in various shapes, and for example, the display device DD may be provided in a rectangular plate shape having two pairs of sides parallel to each other, but the present disclosure is not limited thereto. In the case where the display device DD is provided in a rectangular plate shape, one pair of the two pairs of sides may be provided to be longer than the other pair of sides. In the accompanying drawings, the display device DD has an angled corner portion formed by a straight line, but the present disclosure is not limited thereto. According to an embodiment, the display device DD provided in a rectangular plate shape may have a rounded shape at a corner portion where one long side or one long side and one short side or one short side contact each other.

[0059] In an embodiment of the present disclosure, for ease of description, a case is provided in which the display device DD has a rectangular shape having a pair of long sides and a pair of short sides, and an extending direction of the long sides may be indicated as a first direction DR1, an extending direction of the short sides may be indicated as a third direction DR3, and a direction perpendicular to the extending directions of the long sides and the short sides may be indicated as a second direction DR2. The first direction DR1, the second direction DR2, and the third direction DR3 may refer to directions indicated by the first direction DR1, the second direction DR2, and the third direction DR3, respectively.

[0060] In an embodiment of the present disclosure, at least a portion of the display device DD may have flexibility, and the portion having flexibility may be foldable.

[0061] Figure 2 It is shown Figure 1 A block diagram of an embodiment of a display device.

[0062] refer to Figure 2 , the display device DD may include a display panel DP, a controller 110 , a data driver 120 , a scan driver 130 , and a power driver 140 .

[0063] The display panel DP may include pixels PX. The display panel DP may be connected to scan lines SL1 to SLm and data lines DL1 to DLn. The scan lines SL1 to SLm and the data lines DL1 to DLn may be arranged to intersect each other on the display panel DP. The pixels PX may be electrically connected to the scan lines SL1 to SLm and the data lines DL1 to DLn in the display panel DP.

[0064] The display panel DP may be various types of panels, such as an organic light emitting diode (OLED) panel. The types of lines provided in the display panel DP may vary according to a pixel structure, a panel type, and the like within the spirit and scope of the present disclosure.

[0065] The controller 110 may control operations of the data driver 120, the scan driver 130, and the power driver 140. The controller 110 may provide a first control signal SCS to the scan driver 130 according to a timing implemented in each frame to apply a scan signal to the scan lines SL1 to SLm. The controller 110 may provide an image data signal DATA converted from a data format of an image signal to fit an interface specification of the data driver 120. In the case where the scan signal is applied to the scan lines SL1 to SLm, the controller 110 may provide a second control signal DCS to the data driver 120 to apply a data voltage to the data lines DL1 to DLn.

[0066] The controller 110 may be a timing controller used in display technology, or may be a control device that may perform another control function by including a timing controller.

[0067] The data driver 120 may output data signals to the data lines DL1 to DLn. For example, the data driver 120 may receive the second control signal DCS and the image data signal DATA from the controller 110. The data driver 120 may convert the image data signal DATA into a data signal and output the data signal to the data lines DL1 to DLn. Here, the data signal may be an analog voltage corresponding to the grayscale value of the image data signal DATA. For example, in the case where the selectable scan line is selected by the scan driver 130, the data driver 120 may provide an analog data voltage to the data lines DL1 to DLn.

[0068] The scan driver 130 may receive a first control signal SCS from the controller 110. The scan driver 130 may output scan signals to the scan lines SL1 to SLm. The scan driver 130 may sequentially provide scan signals to the scan lines SL1 to SLm according to the first control signal SCS from the controller 110. The pixel PX receiving each scan signal may receive an analog voltage corresponding to a grayscale value of the image data signal DATA and output light of a brightness corresponding to the analog voltage. Thus, an image may be displayed on the display panel DP.

[0069] The power driver 140 can generate a first viewing angle control voltage VCV1 and a second viewing angle control voltage VCV2. Figure 2 1, but the power driver 140 may generate the first power voltage, the second power voltage, the initialization voltage, and other voltages within the spirit and scope of the present disclosure. The power driver 140 may provide the first viewing angle control voltage VCV1 and the second viewing angle control voltage VCV2 to the electrodes of the display panel DP through the first viewing angle control voltage line VCVL1 and the second viewing angle control voltage line VCVL2. The first viewing angle control voltage VCV1 may be the voltage provided to the first electrode 20 (refer to FIG. 1 ). Figure 3 ), and the second viewing angle control voltage VCV2 may be provided to the second electrode 50 (reference Figure 3 ) voltage. For example, the first viewing angle control voltage VCV1 and the second viewing angle control voltage VCV2 may be determined according to the operation mode of the display device DD. The first viewing angle control voltage VCV1 may be higher than the second viewing angle control voltage VCV2. At this time, the second viewing angle control voltage VCV2 may be a ground voltage or a voltage lower than the ground voltage. The first viewing angle control voltage VCV1 may be lower than the second viewing angle control voltage VCV2. At this time, the first viewing angle control voltage VCV1 may be a ground voltage or a voltage lower than the ground voltage.

[0070] At least one of the controller 110, the data driver 120, the scan driver 130, and the power driver 140 may be mounted on the display panel DP in the form of an integrated circuit chip. Another portion of the controller 110, the data driver 120, the scan driver 130, and the power driver 140 may be attached to the display panel DP in the form of a tape carrier package (TCP), or may be mounted on a separate printed circuit board.

[0071] Figure 3 It is along Figure 1 A schematic cross-sectional view taken along line II'.

[0072] refer to Figure 3 , the display device DD may include a display module 10 , a first electrode 20 , an electronic ink layer 30 , an adhesive layer 40 , a second electrode 50 , and a window 60 .

[0073] The display module 10 can be displayed through the display area DA (refer to Figure 1 ) displays an image. The display module 10 may include a display panel capable of self-emission, such as an organic light-emitting display panel (OLED panel) using an organic light-emitting diode as a light-emitting element, an ultra-small light-emitting diode display panel (nano-LED display) using an ultra-small light-emitting diode as a light-emitting element, and a quantum dot organic light-emitting display panel (QD OLED panel) using quantum dots and organic light-emitting diodes. The display module 10 may include a non-emissive display panel, such as a liquid crystal display panel (LCD panel), an electrophoretic display panel (EPD panel), and an electrowetting display panel (EWD panel). In the case of using a non-emissive display panel, the display device DD may also include a backlight unit that provides light to the display panel.

[0074] The display module 10 may include Figure 2 The display module 10 may include a substrate, a light emitting element, and a driving circuit for driving the light emitting element. For example, in the case where the light emitting element is an organic light emitting element, each of the light emitting elements may include a pixel electrode, an organic light emitting layer, and a common electrode. When holes and electrons injected from the pixel electrode and the common electrode into the organic light emitting layer recombine and drop from an excited state to a ground state, the light emitting element may emit light. The light emitting element may be connected to a driving circuit, and the driving circuit may respond to a signal from Figure 2 The data driver 120, the scan driver 130, and the power driver 140 are operated according to the signals and voltages of the data driver 120, the scan driver 130, and the power driver 140, and the light emitting element may emit light according to the operation of the driving circuit.

[0075] The first electrode 20 and the second electrode 50 may be disposed on the display module 10. The first electrode 20 and the second electrode 50 may include a transparent conductive material. Even if the first electrode 20 and the second electrode 50 are disposed on the display module 10, the first electrode 20 and the second electrode 50 may transmit light incident from the lower portion. For example, the first electrode 20 and the second electrode 50 may include indium tin oxide (ITO). The first electrode 20 and the second electrode 50 may include indium zinc oxide (IZO), indium tin zinc oxide (ITZO) or aluminum zinc oxide (AZO). However, the present disclosure is not limited thereto.

[0076] The electronic ink layer 30 may be disposed between the first electrode 20 and the second electrode 50. The electronic ink layer 30 may include electronic ink. Here, the electronic ink may include a solvent and carbon particles dispersed in the solvent. Therefore, the light transmittance of the electronic ink layer 30 may be controlled according to the voltage difference between the first electrode 20 and the second electrode 50. In other words, the light transmittance of the electronic ink layer 30 may be controlled according to the first viewing angle control voltage VCV1 (reference voltage VCV1) applied to the first electrode 20. Figure 2 ) and a second viewing angle control voltage VCV2 (reference voltage VCV2) applied to the second electrode 50 Figure 2 ) to control the transmittance of the electronic ink layer 30, and thus the display device DD can operate in the viewing angle blocking mode and the wide viewing angle mode. Figure 8 and Fig. 9 A detailed description is given of the electronic ink layer 30 according to the operation mode of the display device DD.

[0077] The adhesive layer 40 may be disposed between the electronic ink layer 30 and the second electrode 50, and may be adhered to one surface or one surface of the electronic ink layer 30 and one surface or one surface of the second electrode 50. The adhesive layer 40 may include a material having a high light transmittance, such as an adhesive film or a resin. The adhesive layer 40 may include at least one of an optically clear resin (OCR), an optically clear adhesive (OCA), and a pressure sensitive adhesive (PSA).

[0078] The window 60 can protect the display panel from external impacts and provide an input surface and / or a display surface to the user. For example, the window 60 can have a multilayer structure selected from a glass substrate, a plastic film, and a plastic substrate. The multilayer structure can be formed by a continuous process or a bonding process using an adhesive layer. A portion of the window 60 or the entire window 60 can be flexible.

[0079] Figure 4 It is shown Figure 3 Schematic cross-sectional view of an embodiment of an electronic ink layer.

[0080] refer to Figure 4 , the electronic ink layer 30 may include partition walls PW. The electronic ink layer 30 may define an inner space IS that may accommodate electronic ink between the partition walls PW. The electronic ink layer 30 may further include a base layer BL disposed on the first electrode 20 to support the partition walls PW.

[0081] The partition walls PW may protrude from the base layer BL in the second direction DR2. For example, the second direction DR2 may be the thickness direction of the electronic ink layer 30. The partition walls PW may be arranged to be spaced apart from each other on the base layer BL in a direction perpendicular to the second direction DR2. For example, each of the partition walls PW may have a first surface 31 facing the base layer BL and a second surface 32 facing the second electrode 50. The first surface 31 and the second surface 32 may be opposite surfaces. The width W1 of the first surface 31 may be wider than or equal to the width W2 of the second surface 32. Each of the partition walls PW may have a side surface 33 connecting the first surface 31 and the second surface 32. The side surface 33 of the partition wall PW may have a tapered shape. Therefore, the cross-section of each of the partition walls PW may have a trapezoidal shape.

[0082] The partition wall PW may include a transparent polymer insulating material. The partition wall PW may be a single layer or a multi-layer. However, the configuration material and / or stacking structure of the partition wall PW is not limited thereto.

[0083] Since the side surface 33 of each of the partition walls PW has a tapered shape, the internal space IS located between the partition walls PW may have a shape complementary to the tapered shape, for example, an inverted trapezoidal shape. It is understood that the internal space IS has the same depth as the height H of the partition wall PW protruding from the base layer BL. For example, the internal space IS may have a depth corresponding to the height H between the first surface 31 and the second surface 32 of the partition wall PW. The internal space IS may have a third width W3 at the height of the first surface 31 of the partition wall PW. The internal space IS may have a fourth width W4 at the height of the second surface 32 of the partition wall PW. At this time, the third width W3 may be equal to or narrower than the fourth width W4. For example, the third width W3 of the internal space IS may be about 10 μm, and the fourth width W4 of the internal space IS may be about 20 μm. The depth of the internal space IS may be in the range of about 50 to about 100 μm. The distance between the internal spaces IS may be about 45 μm, which may be the width W1 of the first surface 31 of the partition wall PW. However, this is an example and is not limited thereto.

[0084] Each of the internal spaces IS may have a substantially concave shape between the partition walls PW. The substantially concave shape of each of the internal spaces IS may be formed by a physical process method such as a master mold process, an imprint process, or a photolithography process. Therefore, the internal space IS may have a shape in which a lower end corresponding to the first surface 31 is narrow and an upper end corresponding to the second surface 32 is wide. The internal space IS may be formed to be spaced apart from the first electrode 20 by the base layer BL. In this case, a reduction in productivity and defects due to leakage of the electronic ink contained in the internal space IS may be prevented.

[0085] When viewed in a direction opposite to the second direction DR2, each of the internal spaces IS may have a closed planar shape. The planar shape of each of the internal spaces IS may be a quadrilateral shape, a circular shape, or a shape in which a curve and a straight line are combined. However, the present disclosure is not limited thereto as long as electronic ink can be accommodated.

[0086] Figure 5 It is shown Figure 3 Schematic cross-sectional view of an embodiment of an electronic ink layer.

[0087] refer to Figure 5 , the electronic ink layer 30 ′ may include partition walls PW′, each of which has a rectangular shape.

[0088] The partition walls PW' may protrude from the first electrode 20 in the second direction DR2. The partition walls PW' may be disposed to be spaced apart from each other in a direction perpendicular to the second direction DR2 on the first electrode 20. For example, each of the partition walls PW' may have a first surface 34 facing the first electrode 20 and a second surface 35 facing the second electrode 50. The first surface 34 and the second surface 35 may be surfaces facing each other.

[0089] The cross section of each of the partition walls PW' may have a short side in the first direction DR1 and a long side in the second direction DR2. The first surface 34 and the second surface 35 of each of the partition walls PW' may have the same width W5. Therefore, the cross section of each of the partition walls PW' may have a rectangular shape.

[0090] When the side surface 36 of the partition wall PW' extends perpendicular to the first electrode 20, each of the internal spaces IS' between the partition walls PW' may also have a rectangular shape. For example, each of the internal spaces IS' may have the same width W6 between the first surface 34 and the second surface 35. The internal space IS' may have a depth equal to the height H' of the partition wall PW'.

[0091] As described above, the partition wall PW' may have various shapes, but is not limited thereto.

[0092] Figure 6 is a diagram showing a manufacturing step of a display device in which electronic ink is contained in Figure 4 Schematic cross-sectional view of a display device in the step of an electronic ink layer.

[0093] refer to Figure 6 The electronic ink layer 30 may contain electronic ink INK capable of absorbing light in the internal space IS.

[0094] The electronic ink INK may be injected into the internal space IS using liquid crystal dripping (drip irrigation technology (ODF)) to cover the electronic ink layer 30. The electronic ink INK may be injected into the internal space IS using inkjet, liquid dispensing, etc., and is not limited thereto. However, when the electronic ink INK is applied to the open surface of the electronic ink layer 30, the electronic ink INK may be maintained not only in the internal space IS but also on the second surface 32 of the partition wall PW (see Figure 4 ). The electronic ink INK remaining on the second surface 32 of the partition wall PW may form a residual film layer. For example, the carbon particles CB included in the electronic ink INK may remain in the residual film layer formed on the second surface 32 of the partition wall PW.

[0095] The electronic ink INK may include a solvent SOL and carbon particles CB dispersed in the solvent SOL. For example, the carbon particles CB may be colored carbon nanotube particles and may be carbon black, manganese ferrite black spinel, copper chromite black spinel, or the like within the spirit and scope of the present disclosure. The solvent SOL may be transparent, may be a low viscosity insulating solvent, and may be a fluid or oil.

[0096] The solvent SOL may have the same refractive index as the partition wall PW. For example, in the case where the partition wall PW includes a transparent resin having a refractive index of 1.41, the solvent SOL may be oil having a refractive index of 1.41. For example, the solvent SOL has the same refractive index as the partition wall PW, thereby minimizing total reflection and ensuring constant transmittance.

[0097] The carbon particles CB may absorb light incident from the outside into the electronic ink INK. The solvent SOL may uniformly disperse the carbon particles CB in the internal space IS and prevent the carbon particles CB from settling due to gravity.

[0098] The carbon particles CB may be black particles and may be negatively charged (or positively charged) particles. In the case of forming an electric field, the carbon particles CB may be moved by electric force. For example, in the case where electric force does not act on the carbon particles CB, the carbon particles CB may be uniformly dispersed and distributed in the solvent SOL. On the other hand, in the case where electric force acts on the carbon particles CB, the carbon particles CB may be distributed near a given position in the solvent SOL.

[0099] Figure 7 is a diagram showing a manufacturing step of a display device in which a second electrode and a window are provided Figure 6 Schematic cross-sectional view of a display device with steps on an electronic ink layer.

[0100] refer to Figure 6 and Figure 7 The second electrode 50 and the window 60 are disposed on the electronic ink layer 30 in which the electronic ink INK is accommodated. The adhesive layer 40 may be formed on a lower surface of the second electrode 50 and may be disposed between the second electrode 50 and the electronic ink layer 30.

[0101] In the case where the adhesive layer 40 adheres to the electronic ink layer 30 in a state where the electronic ink INK is maintained on the second surface 32 of the partition wall PW, the transmittance may be reduced due to the carbon particles CB included in the electronic ink INK. On the other hand, according to an embodiment, the carbon particles CB included in the electronic ink INK may move to the internal space IS, and the adhesive layer 40 may adhere to the electronic ink layer 30.

[0102] First, a voltage for forming an electric field may be applied to the first electrode 20 and the second electrode 50 (wherein the electronic ink layer 30 is disposed between the first electrode 20 and the second electrode 50). For example, a first viewing angle control voltage VCV1 may be applied to the first electrode 20 through a first viewing angle control voltage line VCVL1. A second viewing angle control voltage VCV2 may be applied to the second electrode 50 through a second viewing angle control voltage line VCVL2. In this case, an electric field may be formed in the electronic ink layer 30. At this time, the first viewing angle control voltage VCV1 may be a positive voltage, and the second viewing angle control voltage VCV2 may be a ground voltage or a negative voltage. As the voltage difference between the first electrode 20 and the second electrode 50 increases, the intensity of the electric field formed in the electronic ink layer 30 may increase. For example, the first viewing angle control voltage VCV1 may be a voltage of about 100V or more, and the second viewing angle control voltage VCV2 may be a voltage of about 0V or less. However, the present disclosure is not limited thereto.

[0103] The negatively charged carbon particles CB may receive electrical attraction by the formed electric field. The electrically attracted carbon particles CB may move to an area in the internal space IS adjacent to the first electrode 20 to which the positive voltage is applied. For example, the carbon particles CB included in the electronic ink INK may be distributed near the first electrode 20 in the internal space IS. On the other hand, only the solvent SOL not including the carbon particles CB may remain in the residual film layer formed on the second surface 32 of the partition wall PW. In this state, the adhesive layer 40 may adhere to the second surface 32 of the partition wall PW to bond the electronic ink layer 30 between the first electrode 20 and the second electrode 50.

[0104] According to an example, the voltage applied when the electronic ink layer 30 and the adhesive layer 40 are adhered may be a high voltage so that the carbon particles CB do not remain between the bonded electronic ink layer 30 and the adhesive layer 40. The voltage applied when the electronic ink layer 30 and the adhesive layer 40 are adhered may be higher than a voltage applied to the first electrode 20 according to an operation mode of the display device after manufacturing the display device.

[0105] As described above, in a state in which a voltage is applied to the first electrode 20 and the second electrode 50, the second electrode 50 may be adhered to the electronic ink layer 30 through the adhesive layer 40. In this case, only the solvent SOL not including the carbon particles CB may remain between the electronic ink layer 30 and the adhesive layer 40. Therefore, the problem of reduced transmittance of the upper surface of the electronic ink layer 30 due to the carbon particles CB included in the electronic ink INK may be improved.

[0106] Figure 8 is shown operating in wide viewing mode Figure 1 Schematic cross-sectional view of an embodiment of a display device.

[0107] refer to Figure 8 , in the case where an electric field is formed between the first electrode 20 and the second electrode 50, the display device DD can operate in a wide viewing angle mode. According to an example, in the case where an electric field is formed between the first electrode 20 and the second electrode 50, the carbon particles CB may not be uniformly dispersed in the solvent SOL. The carbon particles CB may be distributed near the first electrode 20 in the internal space IS. In the region not adjacent to the first electrode 20 in the internal space IS, only the solvent SOL may remain without the carbon particles CB. The solvent SOL disposed in the region not adjacent to the first electrode 20 in the internal space IS may transmit incident light with the same transmittance as the partition wall PW. In this case, in the electronic ink layer 30, the optical opening that allows light emitted from the display module 10 to pass through may be expanded. Therefore, the display device DD may operate in a wide viewing angle mode in which external light may be transmitted through the display device DD. In the wide viewing angle mode, the display device DD may be used as a transparent display device.

[0108] In order to form an electric field between the first electrode 20 and the second electrode 50, voltages may be applied to the first electrode 20 and the second electrode 50, respectively. A positive voltage may be applied to the first electrode 20 during a predetermined time, and a ground voltage or a negative voltage may be applied to the second electrode 50 during a predetermined time. Here, the time in the case where the voltage is applied to the first electrode 20 and the second electrode 50 may be set to a range of about 1 s to about 2 s. For example, in the case where a first viewing angle control voltage VCV1 of about 10 V or more and about 50 V or less is applied to the first electrode 20, a second viewing angle control voltage VCV2 of about 0 V or less may be applied to the second electrode 50. However, this is an example and is not limited thereto.

[0109] As described above, since the light-blocking carbon particles CB are distributed near the first electrode 20, the optical opening can be expanded in the upper portion of the internal space IS. Therefore, the display device DD can operate in a wide viewing angle mode of transmitting light. Therefore, the display device DD can prevent the reduction of brightness by moving the carbon particles CB to open the light emission path.

[0110] Fig. 9 is shown operating in view blocking mode Figure 1 Schematic cross-sectional view of an embodiment of a display device.

[0111] refer to Fig. 9, in the case where no electric field is formed between the first electrode 20 and the second electrode 50, the display device DD can operate in a viewing angle blocking mode. According to an example, in the case where a voltage is not applied to the first electrode 20 and the second electrode 50, an electric field may not be formed between the first electrode 20 and the second electrode 50. In this case, the electric force may not act on the carbon particles CB included in the electronic ink INK. Therefore, the carbon particles CB may be uniformly dispersed in the solvent SOL and dispersed and distributed in the internal space IS. When the carbon particles CB are dispersed and distributed in the internal space IS, the dispersed carbon particles CB may absorb incident light. For example, in the case where an electric field is not formed between the first electrode 20 and the second electrode 50, light incident at a viewing angle of a certain angle or greater may be blocked by the carbon particles CB dispersed in the internal space IS. Therefore, the display device DD may operate in a viewing angle blocking mode that does not transmit external light. Therefore, the display device DD may improve the visibility of an image displayed on the display panel by blocking external light.

[0112] As another example, in order to switch from the wide viewing angle mode to the viewing angle blocking mode relatively quickly, it is necessary to remove the electric field formed between the first electrode 20 and the second electrode 50 relatively quickly. In this case, a voltage pulse may be applied to each of the first electrode 20 and the second electrode 50. During a predetermined time, a positive voltage and a negative voltage may be alternately applied to each of the first electrode 20 and the second electrode 50. Here, the time in the case where the voltage is applied to the first electrode 20 and the second electrode 50 may be set to three times or more of about 100ms to about 200ms. However, this is an example and is not limited thereto. For example, in the case where a positive voltage is applied to the first electrode 20, a negative voltage may be applied to the second electrode 50. In the case where a negative voltage is applied to the first electrode 20, a positive voltage may be applied to the second electrode 50. For example, in the case where a first viewing angle control voltage VCV1 of about 10V or more and about 50V or less is applied to the first electrode 20, a second viewing angle control voltage VCV2 of about 0V or less may be applied to the second electrode 50. In the case where the first viewing angle control voltage VCV1 of about 0V or less is applied to the first electrode 20, the second viewing angle control voltage VCV2 of about 10V or more and about 50V or less may be applied to the second electrode 50. For example, the display device DD may be relatively quickly switched from the wide viewing angle mode to the viewing angle blocking mode by applying a voltage pulse to each of the first electrode 20 and the second electrode 50. Therefore, the display device DD may quickly perform mode switching according to the needs of the user.

[0113] In the following, the manufacturing reference is described Figures 1 to 9 A method of displaying a device is described.

[0114] Fig.10is a flowchart showing an embodiment of a method for manufacturing a display device. Figures 1 to 9 Duplicate content of description.

[0115] refer to Figure 3 and Fig.10 In S1010 , a first electrode 20 may be formed on the display module 10 .

[0116] refer to Figure 4 and Fig.10 In S1020 , an electronic ink layer 30 may be formed, the electronic ink layer 30 may include partition walls PW, and in the electronic ink layer 30 , an inner space IS having a substantially concave shape to accommodate the electronic ink INK between the partition walls PW is located.

[0117] According to an embodiment, the electronic ink layer 30 may include partition walls PW protruding from the base layer BL in the second direction DR2. The partition walls PW may be arranged to be spaced apart from each other on the base layer BL in a direction perpendicular to the second direction DR2. For example, each of the partition walls PW may have a first surface 31 facing the base layer BL and a second surface 32 facing the second electrode 50. The first surface 31 and the second surface 32 may be surfaces facing each other. The width W1 of the first surface 31 may be wider than or equal to the width W2 of the second surface 32. Each of the partition walls PW may have a side surface 33 connecting the first surface 31 and the second surface 32. The side surface 33 of each of the partition walls PW may have a tapered shape. The cross-section of each of the partition walls PW may have a trapezoidal shape.

[0118] The partition wall PW may include a transparent polymer insulating material. For example, the adhesive layer 40 may include a material having high light transmittance, such as an adhesive film or a resin.

[0119] The electronic ink layer 30 may define an inner space IS having a substantially concave shape between the partition walls PW. The substantially concave shape of the inner space IS may be formed by a physical process method such as a master mold process, an imprint process, or a photolithography process.

[0120] Since the side surface 33 of the partition wall PW has a tapered shape, each of the internal spaces IS located between the partition walls PW may have a shape complementary to the tapered shape, for example, an inverse trapezoidal shape. Each of the internal spaces IS may have a depth equal to a height H of the partition wall PW protruding from the base layer BL.

[0121] refer to Figure 7 and Fig.10 , in S1030 , a second electrode 50 may be formed.

[0122] refer to Figure 6and Fig.10 In S1040 , the electronic ink INK may be injected into the internal space IS of the electronic ink layer 30 using liquid crystal droplets.

[0123] According to an embodiment, the electronic ink INK may be injected into the internal space IS using liquid crystal dripping (drip irrigation technology (ODF)) to cover the electronic ink layer 30. The electronic ink INK may be injected into the internal space IS using inkjet, liquid dispensing, etc., without limitation thereto. However, when the electronic ink INK is applied to the open surface of the electronic ink layer 30, the electronic ink INK may be retained not only in the internal space IS but also on the second surface 32 of the partition wall PW. The electronic ink INK retained on the second surface 32 of the partition wall PW may form a residual film layer. For example, the carbon particles CB included in the electronic ink INK may be retained in the residual film layer formed on the second surface 32 of the partition wall PW.

[0124] The electronic ink INK may include a solvent SOL and carbon particles CB dispersed in the solvent SOL. For example, the carbon particles CB may be colored carbon nanotube particles and may be carbon black, manganese ferrite black spinel, copper chromite black spinel, or the like within the spirit and scope of the present disclosure. The solvent SOL may be transparent, may be a low viscosity insulating solvent, and may be a fluid or oil.

[0125] The carbon particles CB can play a role in absorbing a large amount of light incident from the outside into the electronic ink INK. The carbon particles CB can be black particles and can be negatively charged (or positively charged) particles. In the case of forming an electric field, the carbon particles CB can be moved by electricity. For example, in the case where electricity does not act on the carbon particles CB, the carbon particles CB can be uniformly dispersed and distributed in the solvent SOL. On the other hand, in the case where electricity acts on the carbon particles CB, the carbon particles CB can be distributed near a given position in the solvent SOL.

[0126] refer to Figure 7 and Fig.10 In S1050 , a voltage may be applied to the first electrode 20 and the second electrode 50 to move carbon particles CB included in the electronic ink INK of the electronic ink layer 30 , and an adhesive layer 40 adhered to one surface or one surface of the electronic ink layer 30 may be formed.

[0127] In the case where the adhesive layer 40 adheres to the electronic ink layer 30 in a state where the electronic ink INK is maintained on the second surface 32 of the partition wall PW, the transmittance may be reduced due to the carbon particles CB included in the electronic ink INK. On the other hand, according to an embodiment, the carbon particles CB included in the electronic ink INK on the second surface 32 of the partition wall PW may move to the internal space IS, and the adhesive layer 40 may adhere to the electronic ink layer 30.

[0128] First, a voltage for forming an electric field may be applied to the first electrode 20 and the second electrode 50 (wherein the electronic ink layer 30 is disposed between the first electrode 20 and the second electrode 50). For example, the first viewing angle control voltage VCV1 may be applied to the first electrode 20 through the first viewing angle control voltage line VCVL1. The second viewing angle control voltage VCV2 may be applied to the second electrode 50 through the second viewing angle control voltage line VCVL2. In this case, an electric field may be formed in the electronic ink layer 30. At this time, the first viewing angle control voltage VCV1 may be a positive voltage, and the second viewing angle control voltage VCV2 may be a ground voltage or a negative voltage. As the voltage difference between the first electrode 20 and the second electrode 50 increases, the intensity of the electric field formed in the electronic ink layer 30 may increase. For example, the first viewing angle control voltage VCV1 may be a voltage of about 100V or more, and the second viewing angle control voltage VCV2 may be a voltage of about 0V or less. However, the present disclosure is not limited thereto.

[0129] The negatively charged carbon particles CB may receive electrical attraction by the formed electric field. The electrically attracted carbon particles CB may move to an area in the internal space IS adjacent to the first electrode 20 to which the positive voltage is applied. For example, the carbon particles CB included in the electronic ink INK may be distributed near the first electrode 20 in the internal space IS. On the other hand, only the solvent SOL not including the carbon particles CB may remain in the residual film layer formed on the second surface 32 of the partition wall PW. In this state, the adhesive layer 40 may adhere to the second surface 32 of the partition wall PW to bond the electronic ink layer 30 between the first electrode 20 and the second electrode 50.

[0130] According to an example, the voltage applied when the electronic ink layer 30 and the adhesive layer 40 are adhered may be a high voltage so that the carbon particles CB do not remain between the bonded electronic ink layer 30 and the adhesive layer 40. The voltage applied when the electronic ink layer 30 and the adhesive layer 40 are adhered may be higher than a voltage applied to the first electrode 20 according to an operation mode of the display device after manufacturing the display device.

[0131] As described above, in a state where a voltage is applied to the first electrode 20 and the second electrode 50, the second electrode 50 may be adhered to the electronic ink layer 30 through the adhesive layer 40. In this case, only the solvent SOL not including the carbon particles CB may remain between the electronic ink layer 30 and the adhesive layer 40. Therefore, the problem of reduced transmittance of the upper surface of the electronic ink layer 30 due to the carbon particles CB included in the electronic ink INK may be improved.

[0132] According to an embodiment, a display apparatus having improved efficiency by adjusting a viewing angle and a method of manufacturing the same are provided.

[0133] The effects according to the embodiments are not limited to the above, and various effects are also included in the specification.

[0134] Although embodiments and application examples are described herein, other embodiments and modifications can be derived from the above description. Therefore, the spirit of the present disclosure is not limited to these embodiments, but extends to the appended claims, various modifications and equivalent scopes.

Claims

1. Display equipment, including: Light emitting element; A first electrode, disposed on the light emitting element; an electronic ink layer, comprising a partition wall disposed on the first electrode, the partition wall comprising an inner space having a concave shape to accommodate the electronic ink between the partition walls; A second electrode is disposed on the electronic ink layer; as well as an adhesive layer disposed between the electronic ink layer and the second electrode and adhered to a surface of the electronic ink layer, Wherein, the viewing angle is adjusted by moving carbon particles included in the electronic ink according to the voltage difference between the first electrode and the second electrode.

2. The display device according to claim 1, wherein: After a positive voltage is applied to the first electrode and a negative voltage is applied to the second electrode to move the carbon particles toward the first electrode, the binder layer adheres to an upper surface of the partition wall facing the second electrode.

3. The display device according to claim 1, wherein: The electronic ink layer further includes a base layer disposed on the first electrode to support the partition wall, and The partition walls protrude from the base layer in a direction toward the second electrode and are spaced apart from each other on the base layer.

4. The display device according to claim 3, wherein: Each of the partition walls has a first surface facing the base layer and a second surface opposite to the first surface and facing the second electrode, and The width of the first surface is wider than or equal to the width of the second surface.

5. The display device according to claim 1, wherein: The partition wall and a solvent included in the electronic ink have the same refractive index.

6. The display device according to claim 1, wherein: The display device operates in one of a viewing angle blocking mode and a wide viewing angle mode, In a case where the display device is operated in the viewing angle blocking mode, the carbon particles are dispersed and distributed in the inner space of the partition wall, and In a case where the display device operates in the wide viewing angle mode, the carbon particles are distributed near the first electrode.

7. The display device according to claim 1, wherein: The display device operates in one of a viewing angle blocking mode and a wide viewing angle mode, and In a case where the display device operates in the wide viewing angle mode, a positive voltage is applied to the first electrode and a negative voltage is applied to the second electrode.

8. The display device according to claim 1, wherein: The display device operates in one of a viewing angle blocking mode and a wide viewing angle mode, and In a case where the display device operates in the viewing angle blocking mode, a voltage pulse is applied to the first electrode and the second electrode.

9. The display device according to claim 8, wherein: In the viewing angle blocking mode, in the case where a positive voltage is applied to the first electrode, a negative voltage is applied to the second electrode, and in the case where a negative voltage is applied to the first electrode, a positive voltage is applied to the second electrode.

10. A method for manufacturing a display device, the method comprising: forming a first electrode disposed on the light emitting element; forming an electronic ink layer including partition walls on the first electrode, the partition walls including an inner space having a concave shape to accommodate the electronic ink between the partition walls; forming a second electrode on the electronic ink layer; as well as forming an adhesive layer disposed between the electronic ink layer and the second electrode and adhered to a surface of the electronic ink layer, Wherein, forming the adhesive layer includes adhering the adhesive layer to the surface of the electronic ink layer after carbon particles included in the electronic ink move toward the first electrode due to a positive voltage applied to the first electrode and a negative voltage applied to the second electrode.

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