Viewing angle controllable touch panel device and display device

Abstract

The invention relates to a visual angle controllable touch panel device and a display device. The visual angle controllable touch panel device includes: an upper transparent substrate; a lower transparent substrate; a lower viewing angle control electrode on a top surface of the lower transparent substrate; a lower touch panel electrode on a top surface of the lower transparent substrate; an upper touch panel electrode on a bottom surface of the upper transparent substrate; and an electrophoretic element disposed between a bottom surface of the upper transparent substrate and a top surface of the lower transparent substrate. The electrophoretic element includes electrophoretic particles and a dispersion medium. The lower touch panel electrode is included in a layer above the lower viewing angle control electrode. The lower touch panel electrode at least partially overlaps the lower viewing angle control electrode in a plan view. The electrophoretic element is sandwiched between one of the upper touch panel electrodes and the lower viewing angle control electrode.

Description

Technical Field

[0001] This invention relates to a viewing angle controllable touch panel device and a display device. Background Technology

[0002] Smartphones and tablets, as electronic devices that include display devices with input capabilities (i.e., touch panels), are widely available around the world. These devices are used as tools for sharing information with many people in various scenarios.

[0003] Touch panels come in various types, such as capacitive, resistive, optical, ultrasonic, and electromagnetic induction; most smartphones and tablets use capacitive touch panels. Touch panels are used in various display devices, such as liquid crystal displays (LCDs) and organic electroluminescent (EL) displays. In recent years, considering the advantages of achieving thinner displays, so-called "on-cell" technology has been adopted. This on-cell technology places the touch panel's circuitry directly above the inorganic or organic encapsulation film that encapsulates the organic electroluminescent (EL) element.

[0004] Meanwhile, from the perspective of personal information protection, display devices with viewing angle limiting functions are widely available to prevent people from peeping at the displayed images in public spaces such as parks, trains, and ATMs. In particular, display devices capable of switching between wide and narrow viewing angles are especially noteworthy.

[0005] Several methods for actively controlling the switching of viewing angles between wide and narrow viewing angles are known. One example uses a light-shielding plate and polymer network liquid crystal (PNLC). Another known example uses electrophoretic ink, which has a relatively short response time when switching between wide and narrow viewing angles. Display devices employing either method have two electrodes and utilize the electric field generated between these electrodes to control the viewing angle.

[0006] Organic EL display devices with touch panel functionality and viewing angle control can become electronic devices suitable for a variety of applications due to their thinner shape and more functions compared to traditional devices. Summary of the Invention

[0007] Capacitive touch panels (touch sensors) detect touch points by measuring the change in capacitance caused by a finger touching the surface of the device. The capacitance changes due to the capacitance generated between the finger and the electrodes.

[0008] When another electrode is provided between the touch panel and the surface of the display device, an electric field is generated between the touch panel and the electrode, but no electric field is generated on the surface of the display device. Therefore, no capacitance is generated between the finger and the electrodes of the touch sensor, and capacitive touch sensing does not function. This means that, in principle, it is difficult to make both functions work properly when simply constructing a structure on the touch panel with active viewing angle control functionality that uses the electric field between the electrodes to control the viewing angle (the direction of travel of transmitted light).

[0009] An alternative configuration, placing the touch panel above the active viewing angle control (active sunshade), does not cause the aforementioned problems. However, stacking the independent viewing angle control and touch panel increases the overall thickness of the device.

[0010] A view-angle controllable touch panel device according to one aspect of the present invention includes: an upper transparent substrate, a lower transparent substrate, a lower view-angle control electrode on a top surface of the lower transparent substrate, a plurality of lower touch panel electrodes on the top surface of the lower transparent substrate, a plurality of upper touch panel electrodes on a bottom surface of the upper transparent substrate, and a plurality of electrophoretic elements disposed between the bottom surface of the upper transparent substrate and the top surface of the lower transparent substrate. Each of the plurality of electrophoretic elements includes electrophoretic particles and a dispersion medium. The plurality of lower touch panel electrodes are included in a layer above the lower view-angle control electrode. In a plan view, each of the plurality of lower touch panel electrodes at least partially overlaps with the lower view-angle control electrode. Each of the plurality of electrophoretic elements is sandwiched between one of the plurality of upper touch panel electrodes and the lower view-angle control electrode.

[0011] A display device according to one aspect of the present invention includes: an OLED display panel, a viewing angle controllable touch panel device disposed on the display panel, and a controller. The viewing angle controllable touch panel device includes: a plurality of upper viewing angle control electrodes; a plurality of first touch panel electrodes and a plurality of second touch panel electrodes disposed on a thin-film encapsulation structure of the OLED display panel without a substrate therebetween; and a plurality of electrophoretic elements disposed between the plurality of upper viewing angle control electrodes and a touch panel electrode array, the touch panel electrode array including the plurality of first touch panel electrodes and the plurality of second touch panel electrodes in a stacking direction, each electrophoretic element including electrophoretic particles and a dispersion medium. The controller is configured to control the potential of the plurality of upper viewing angle control electrodes. The controller is configured to control the potential during alternating sensing and non-sensing periods. The controller is configured to perform touch sensing during the sensing period by controlling the potentials of the plurality of first touch panel electrodes and the plurality of second touch panel electrodes. The controller is configured to control the viewing angle during the non-sensing period by controlling the state of electrophoretic particles in the plurality of electrophoretic elements using the electric field between the plurality of upper viewing angle control electrodes and the plurality of first touch panel electrodes and the plurality of second touch panel electrodes. The non-sensing period is longer than the sensing period.

[0012] One aspect of the present invention integrates a touch panel with a viewing angle control device that controls the viewing angle electrically, so as to share some components.

[0013] It should be understood that the above general description and the following detailed description are exemplary and explanatory, and do not limit the invention. Attached Figure Description

[0014] Figure 1 An example configuration of a display device according to one embodiment of this specification is illustrated schematically.

[0015] Figure 2 This is a schematic cross-sectional view illustrating the structure of a view-controllable touch panel.

[0016] Figure 3 This is a perspective view schematically showing the structure of a view-controllable touch panel.

[0017] Figure 4 An example of the circuit layout for a viewable touch panel is shown.

[0018] Figure 5A Schematic illustration along Figure 4 The VV section line in the diagram represents a cross-sectional structure of a view-controllable touch panel in a narrow viewing angle state.

[0019] Figure 5B Schematic illustration along Figure 4 The cross-sectional structure of the VV section line in the image is a cross-sectional structure of the view-controllable touch panel in a wide viewing angle state.

[0020] Figure 6A Schematic illustration along Figure 4 The section line VI-VI in the figure represents a cross-sectional structure of a touch panel with a controllable viewing angle in a narrow viewing angle state.

[0021] Figure 6B Schematic illustration along Figure 4 The section line VI-VI in the figure represents a cross-sectional structure of a touch panel with a controllable viewing angle in a wide viewing angle state.

[0022] Figure 7A Schematic illustration along Figure 4 The VV section line in the diagram represents another cross-sectional structure of the view-controllable touch panel in a wide-viewing-angle state.

[0023] Figure 7B Schematic illustration along Figure 4 The section line VI-VI in the middle is another cross-sectional structure of the view-controllable touch panel in a wide viewing angle state.

[0024] Figure 8A Another structural example of a view-controllable touch panel is shown.

[0025] Figure 8B An electrophoretic element with an alternative shape is shown.

[0026] Figure 9 An example configuration of a touch panel electrode group obtained by bundling some adjacent touch panel electrodes is shown.

[0027] Figure 10 The relationship between the distance between the upper touch panel electrode and the lower touch panel electrode and the distance between the upper touch panel electrode and the lower viewing angle control electrode is shown.

[0028] Figure 11 This is a timing diagram illustrating an example of how the potentials of the upper touch panel electrode (X electrode), lower touch panel electrode (Y electrode), and lower viewing angle control electrode (C electrode) change over time in narrow viewing angle mode.

[0029] Figure 12 Details of the driving pulses used for touch sensing are shown.

[0030] Figure 13 This is a timing diagram illustrating an example of how the potentials of the upper touch panel electrode (X electrode), the lower touch panel electrode (Y electrode), and the lower viewing angle control electrode (C electrode) change over time in wide viewing angle mode.

[0031] Figure 14 This is a timing diagram illustrating another example of how the potentials of the upper touch panel electrode (X electrode), lower touch panel electrode (Y electrode), and lower viewing angle control electrode (C electrode) change over time in wide viewing angle mode.

[0032] Figure 15A An example configuration of a receiver circuit for an X electrode included in a touch sensor integrated circuit (IC) and its operation is shown.

[0033] Figure 15B An example configuration of the receiver circuitry and its operation of the X electrode included in a touch sensor IC is shown.

[0034] Figure 15C An example configuration of the receiver circuitry and its operation of the X electrode included in a touch sensor IC is shown.

[0035] Figure 16 This is a timing diagram showing another example of how the potentials of the upper touch panel electrode (X electrode), lower touch panel electrode (Y electrode), and lower viewing angle control electrode (C electrode) change over time in narrow viewing angle mode.

[0036] Figure 17 This is a timing diagram showing yet another example of how the potentials of the upper touch panel electrode (X electrode), the lower touch panel electrode (Y electrode), and the lower viewing angle control electrode (C electrode) change over time in wide viewing angle mode.

[0037] Figure 18A A method for manufacturing a display device is shown.

[0038] Figure 18B A method for manufacturing a display device is shown.

[0039] Figure 18C A method for manufacturing a display device is shown.

[0040] Figure 18D A method for manufacturing a display device is shown.

[0041] Figure 18E A method for manufacturing a display device is shown.

[0042] Figure 18F A method for manufacturing a display device is shown.

[0043] Figure 18G A method for manufacturing a display device is shown.

[0044] Figure 18H A method for manufacturing a display device is shown.

[0045] Figure 19 An example layout of the electrophoretic elements is shown.

[0046] Figure 20 An example of the structure of a display device according to another embodiment of this specification is illustrated schematically.

[0047] Figure 21 An example of the electrode layout for a view-adjustable touch panel is shown.

[0048] Figure 22 This is a timing diagram showing an example of how the potentials of the upper shading electrode, the emitting electrode (TP-Tx), and the receiving electrode (TP-Rx) change over time in narrow viewing angle mode.

[0049] Figure 23 This is a timing diagram showing an example of how the potentials of the upper shading electrode, the emitting electrode (TP-Tx), and the receiving electrode (TP-Rx) change over time in a wide-viewing-angle mode.

[0050] Figure 24 This is a cross-sectional view showing another structural example of the transmitting electrode pattern and the receiving electrode pattern.

[0051] Figure 25 This is a plan view showing another structural example of the transmitting electrode pattern and the receiving electrode pattern.

[0052] Figure 26 This is a flowchart illustrating an example of a method for manufacturing a display device including a viewing angle-controlled touch panel located directly above a thin-film encapsulation structure. Detailed Implementation

[0053] In the following description, embodiments will be illustrated with reference to the accompanying drawings. These embodiments are merely examples of implementing the invention and do not limit the scope of the invention. Common elements in the drawings are indicated by the same reference numerals, and some elements in the drawings are exaggerated in size or shape for clear understanding of the description.

[0054] Capacitive touch panels (touch sensors) detect touch points by measuring the change in capacitance caused by a finger touching the surface of the device. The capacitance changes due to the capacitance generated between the finger and the electrodes.

[0055] When another electrode is provided between the touch panel and the surface of the display device, an electric field is generated between the touch panel and the electrode, but no electric field is generated on the surface of the display device. Therefore, no capacitance is generated between the finger and the electrodes of the touch sensor, and capacitive touch sensing does not function. This means that, in principle, it is difficult to make both functions work properly if a structure with active viewing angle control functionality—which uses the electric field between the electrodes to control the viewing angle (the direction of travel of transmitted light)—is simply built on the touch panel.

[0056] An alternative configuration, placing the touch panel above the active viewing angle control (active sunshade), does not cause the aforementioned problems. However, stacking the independent viewing angle control and touch panel increases the overall thickness of the device.

[0057] The viewing angle controllable touch panel in one embodiment of this specification includes a lower viewing angle control electrode and a plurality of lower touch panel electrodes on the top surface of a lower transparent substrate, and a plurality of upper touch panel electrodes on the bottom surface of an upper transparent substrate. The upper touch panel electrodes are electrodes shared by touch sensing and viewing angle control. A plurality of electrophoretic elements are disposed between the bottom surface of the upper transparent substrate and the top surface of the lower transparent substrate. Each electrophoretic element is sandwiched between the upper touch panel electrodes and the lower viewing angle control electrodes. This configuration achieves integration of the viewing angle control device with the touch panel (touch sensor) while simultaneously achieving a relatively small overall device thickness.

[0058] Implementation Method 1

[0059] Figure 1 An example configuration of a display device according to one embodiment of this specification is illustrated schematically. The display device includes a display panel 5 and a viewing angle-controlled touch panel 1 disposed on the front of the display panel 5. The viewing angle-controlled touch panel 1 and the display panel 5 are bonded together by a resin adhesive layer 31. The adhesive layer 31 between the viewing angle-controlled touch panel 1 and the display panel 5 may be disposed only between the outer regions of these panels.

[0060] Display panel 5 can be any type, such as an organic light-emitting diode (OLED) display panel, a liquid crystal display panel, or a micro LED panel. Figure 1 An OLED display panel is shown as an example.

[0061] Display panel 5 includes an OLED element layer 52 above a thin-film transistor (TFT) substrate 51. The OLED element layer 52 and the underlying TFT layer are covered by a thin-film encapsulation structure 53. The OLED element layer 52 includes an OLED element array consisting of a plurality of OLED elements (light-emitting elements) arranged in a plane. Each OLED element is a pixel that emits light in a specific color. All OLED elements can emit white light, or the OLED element layer 52 can include OLED elements for emitting red, green, and blue light.

[0062] The TFT layer includes a pixel circuit array comprising multiple pixel circuits for individually controlling the emission of light from an OLED element. Each pixel circuit includes a driving TFT for controlling the emission current flowing to the OLED element and multiple switching TFTs. Each pixel circuit operates according to a control signal to supply an emission current specified by a data signal to the OLED element from a power line via the driving TFT. Figure 1 The controller, not shown, provides signals and power to the pixel circuit via a flexible printed circuit (FPC) 54.

[0063] The side from which the user views the image on display panel 5, or the side from which the light rays of the image travel, is defined as the front or top side, and the opposite side is defined as the back or bottom side. The direction perpendicular to the main surface of display panel 5 and the main surface of viewing angle controllable touch panel 1 is defined as the Z-axis direction, and two directions perpendicular to each other within any main surface are defined as the X-axis direction and the Y-axis direction. The Z-axis direction is the stacking direction of display panel 5 and viewing angle controllable touch panel 1.

[0064] The viewing angle-controlled touch panel 1 has the function of a touch sensor and also has the function of an active light shield (ALV) for controlling the propagation direction of light transmitted from the light emitted from the display panel 5. The functional layers for touch sensor and light propagation direction control are sandwiched between two glass substrates 111 and 112. Control signals for the viewing angle-controlled touch panel 1 are transmitted, for example, via FPC 154 from... Figure 1 The controller, not shown, is provided.

[0065] The viewing angle controllable touch panel 1 can switch the range of images transmitted on the display panel 5 by switching between a wide viewing angle state and a narrow viewing angle state. The state (mode) in which the viewing angle controllable touch panel 1 emits light at a wide angle is called the wide viewing angle state (wide viewing angle mode), and the state (mode) in which it emits light at a narrow angle is called the narrow viewing angle state (narrow viewing angle mode). Figure 1 A view-controllable touch panel 1 in a narrow viewing angle state is shown.

[0066] A circular polarizer 32 is disposed above the glass substrate 112 on the front side of the viewing angle controllable touch panel 1, and a cover glass 33 is disposed above the circular polarizer 32. An indicator, such as a finger, touches the surface of the cover glass 33, and the viewing angle controllable touch panel 1 detects the touch point. The circular polarizer 32 reduces reflection from the reflective electrodes (e.g., anode electrodes) of the OLED element. The circular polarizer 32 and the cover glass 33 are optional.

[0067] Figure 2 This is a schematic cross-sectional view showing the structure of the viewing angle controllable touch panel 1. Figure 3 This is a perspective view schematically showing the structure of the view-controllable touch panel 1. Figure 2A wide-viewing-angle adjustable touch panel 1 is shown. Figure 3 A view-controllable touch panel 1 in a narrow viewing angle state is shown.

[0068] The viewing angle controllable touch panel 1 changes the dispersion state of colored electrophoretic particles (colored charged particles) 140 in the dispersion medium 141 of each electrophoretic element 114 disposed between the upper glass substrate 112 and the lower glass substrate 111, thereby changing the emission angle range of light transmitted through the region between the upper glass substrate 112 and the lower glass substrate 111. Specifically, in Figure 2 In the wide-viewing-angle state shown, electrophoretic particles 140 aggregate near an electrode, which in this example is the lower-viewing-angle control electrode 126. Figure 3 In the narrow field of view shown, the electrophoretic particles 140 are dispersed in each electrophoretic element 114.

[0069] The viewing angle controllable touch panel 1 includes an upper glass substrate 112 and a lower glass substrate 111. The bottom surface of the lower glass substrate 111 is parallel to... Figure 1 The display panels 5 shown are opposite each other, with their top surfaces facing the bottom surfaces of the upper glass substrate 112. The upper glass substrate 112 and the lower glass substrate 111 are transparent substrates, and they can be made of materials different from glass. For example, they can be made of polyethylene terephthalate (PET), polycarbonate (PC), or polyethylene naphthalate (PEN). The upper glass substrate 112 and the lower glass substrate 111 are flexible or non-flexible insulators.

[0070] The viewing angle controllable touch panel 1 also includes multiple upper touch panel electrodes 121, multiple lower touch panel electrodes 123, and a lower viewing angle control electrode 126. The upper touch panel electrodes 121 and lower touch panel electrodes 123 can be made of transparent conductors such as ITO or ZnO, or of opaque metals such as Mo or Al. The lower viewing angle control electrode 126 can be made of a transparent conductor such as ITO or ZnO. Figure 2 An example of a viewing angle-controlled touch panel 1 of the mutual capacitance type is shown. Another approach, projected capacitance sensing, can be used, namely self-capacitance touch sensing.

[0071] Multiple upper touch panel electrodes (electrode patterns of the upper touch panel) 121 are located on the bottom surface of the upper glass substrate 112. The upper touch panel electrodes 121 are configured to extend along the X-axis direction on the upper glass substrate 112 and be spaced apart from each other along the Y-axis direction. Each upper touch panel electrode 121 may be a strip conductor. The upper touch panel electrode 121 may be referred to as the X electrode.

[0072] Each upper touch panel electrode 121 is opposite to the electrophoretic element 114, but not opposite to the transparent area (light-transmitting area) 115 between the electrophoretic elements 114. The upper touch panel electrode 121 is also the upper viewing angle control electrode, thereby enabling a thinner device. An insulating film 131 is disposed between the electrophoretic element 114 and the upper touch panel electrode 121. Although the material of the insulating film 131 is selected as needed, it can be, for example, silicon nitride or silicon oxide.

[0073] Signals between the upper touch panel electrode 121 and the FPC 154 can be transmitted through an anisotropic conductive film (ACF) 156 that contacts the bottom surface of the upper glass substrate 112 and the top surface of the lower glass substrate 111.

[0074] Multiple lower touch panel electrodes (electrode patterns of the lower touch panel) 123 are located on the top surface of the lower glass substrate 111. The layer of the electrophoretic element 114 is located between the upper touch panel electrode patterns and the lower touch panel electrode patterns. The lower touch panel electrodes 123 are configured to extend along the Y-axis on the lower glass substrate 111 and be spaced apart from each other along the X-axis. Each lower touch panel electrode 123 may be a strip conductor. The lower touch panel electrodes 123 may be referred to as Y electrodes.

[0075] The upper touch panel electrode 121 and the lower touch panel electrode 123 are arranged in a matrix. The capacitance change between the upper touch panel electrode 121 and the lower touch panel electrode 123 can detect the touch point of an indicator (such as a finger).

[0076] An insulating film 132 is disposed between the electrophoretic element 114 and the lower touch panel electrode 123. Although the material of the insulating film 132 covering the lower touch panel electrode 123 is selected as needed, it can be, for example, silicon nitride or silicon oxide.

[0077] The lower viewing angle control electrode 126 is located on the top surface of the lower glass substrate 111. The lower viewing angle control electrode 126 is situated between the layer of the lower touch panel electrode 123 and the top surface of the lower glass substrate 111. In the plan view, at least a portion of the area of ​​the lower touch panel electrode 123 overlaps with the lower viewing angle control electrode 126. An insulating film 133 is disposed between the lower viewing angle control electrode 126 and the lower touch panel electrode 123. Although the material of the insulating film 133 covering the lower viewing angle control electrode 126 is selected as needed, it can be, for example, silicon nitride or silicon oxide.

[0078] The lower viewing angle control electrode 126 is a single, sheet-like electrode opposite to all electrophoretic elements 114 and all upper touch panel electrodes 121. In other words, the lower viewing angle control electrode 126 is a shared lower viewing angle control electrode for all electrophoretic elements 114. The state of the electrophoretic element 114 switches between a light-blocking state and a light-transmitting state due to the voltage (electric field) between the upper touch panel electrodes 121 and the lower viewing angle control electrode 126. The lower viewing angle control electrode 126 covers the viewing angle control area or the area where its state switches between light-blocking and light-transmitting states. The area of ​​the lower viewing angle control electrode 126 is equal to or larger than the area of ​​the viewing angle control area.

[0079] The lower viewing angle control electrode 126 can also be configured as multiple, each of which is opposite to one or more electrophoretic elements 114 and one or more upper touch panel electrodes 121 to control the state of the electrophoretic elements 114. The lower viewing angle control electrode 126 shared by multiple electrophoretic elements 114 can provide a uniform electric field for the electrophoretic elements 114, thereby achieving more uniform viewing angle control in the plane.

[0080] The viewing angle controllable touch panel 1 includes a viewing angle control layer between an upper glass substrate 112 and a lower glass substrate 111. The viewing angle control layer consists of a plurality of electrophoretic elements 114 and transparent areas 115. The transparent areas 115 are light-transmitting areas. The electrophoretic elements 114 and the transparent areas 115 are arranged to be located in the X-axis direction and alternate in the Y-axis direction.

[0081] In the XY plane, multiple electrophoretic elements 114 have a stripe pattern, such that they extend in the X-axis direction and are spaced apart from each other in the Y-axis direction. Transparent regions 115 between the electrophoretic elements 114 also have a stripe pattern, such that they extend in the X-axis direction and are spaced apart from each other in the Y-axis direction. The transparent regions 115 can be made of, for example, a light-transmitting or photosensitive resin. The height of the transparent regions 115 is suitably chosen to match the spacing between the transparent regions and the electrophoretic elements, which is determined to satisfy the viewing angle characteristics required for a viewing angle-controlled touch panel, and can be, for example, from 10 μm to 500 μm.

[0082] Each electrophoretic element 114 can be separate from other electrophoretic elements, or it can be part of an unseparated region. For example, each electrophoretic element can be a cuboid along the X-axis or Y-axis direction in a grid-like region. In this configuration, the transparent regions can be columnar regions separated from each other.

[0083] Each electrophoretic element 114 includes electrophoretic particles 140 contained within spaces formed between transparent regions 115 and a dispersion medium 141 (electrophoretic element material). In other words, within a transparent resin block, the transparent regions 115 and the electrophoretic elements 114 have a ridge-and-groove relationship. The electrophoretic particles 140 are, for example, colored black. The dispersion medium 141 can be a transparent and colorless liquid. The spacing and width of the electrophoretic elements are appropriately selected based on the viewing angle characteristics required by the viewing angle controllable touch panel. When selecting, the pixel layout of the display panel should also be considered to reduce the resulting moiré patterns based on the relationship between the line spacing of the viewing angle controllable touch panel and the pixel spacing of the display panel. For example, the width of the electrophoretic elements 114 can be from 3 μm to 100 μm, and their spacing can be from 3 μm to 1000 μm.

[0084] Each electrophoretic element 114 is sandwiched between an upper touch panel electrode 121 and a lower viewing angle control electrode 126. Figure 2 and Figure 3 In the configuration example, each electrophoretic element 114 is sandwiched between a different upper touch panel electrode and a common lower viewing angle control electrode 126.

[0085] exist Figure 2 and Figure 3 In the example, the electrophoretic element material, composed of electrophoretic particles 140 and dispersion medium 141, does not contact any electrodes, and insulating films 131 and 132 are interposed therebetween. That is, insulating films 131 and 132 are exposed to and in direct contact with the electrophoretic element material. However, these insulating films 131 and 132 are optional.

[0086] In another configuration example, multiple adjacent electrophoretic elements can be sandwiched between an upper touch panel electrode 121 and a lower viewing angle control electrode. That is, multiple electrophoretic elements can be opposite an upper touch panel electrode and a lower viewing angle control electrode in the Z-axis direction. The multiple electrophoretic elements are controlled by the electric field of a pair of electrodes.

[0087] The viewing angle control layer (active light shield) has a relatively large thickness to achieve its function. Therefore, the capacitance between the touch panel electrodes 121 and 123 can be very small, thereby improving the sensitivity of the touch sensor. Thus, even if the space between the upper touch panel electrodes 121 and the lower touch panel electrodes 123 is reduced, touch sensing is not significantly affected. Therefore, a larger number of touch panel electrodes can be provided to reduce jitter (instability in sensing).

[0088] Figure 4An example of the wiring layout for the viewing angle controllable touch panel 1 is shown. The potentials of the upper touch panel electrode 121, the lower touch panel electrode 123, and the lower viewing angle control electrode 126 are controlled by the touch sensor IC 128 of the controller. The touch sensor IC 128 also measures the capacitance change between the upper touch panel electrode 121 and the lower touch panel electrode 123 to detect the touch point of the indicator based on the measurement results. The touch sensor IC 128 can be electrically connected to these electrodes 121, 123, and 126 via the FPC 154 and peripheral wiring on the lower glass substrate 111 and the upper glass substrate 112.

[0089] The upper touch panel electrodes 121 are X electrodes, and they are configured to extend in the X-axis direction and be spaced apart from each other in the Y-axis direction. The width and spacing of the upper touch panel electrodes 121 can be consistent or different. The lower touch panel electrodes 123 are Y electrodes, and they are configured to extend in the Y-axis direction and be spaced apart from each other in the X-axis direction. The width and spacing of the lower touch panel electrodes 123 can be consistent or different. The upper touch panel electrodes 121 can have any shape and can be arranged in any layout, as long as they are suitable for touch sensing and viewing angle control. The lower touch panel electrodes 123 can also have any shape and can be arranged in any layout, as long as they are suitable for touch sensing.

[0090] The lower viewing angle control electrode 126 has a sheet-like shape and overlaps with the upper touch panel electrode 121 and the lower touch panel electrode 123 in a plan view. The upper touch panel electrode 121 is also the upper viewing angle control electrode. The state of the electrophoretic element 114 is controlled by the electric field between the upper touch panel electrode 121 and the lower viewing angle control electrode 126. Although Figure 4 In the example, all the upper touch panel electrodes 121 are paired with the same lower viewing angle control electrode 126, but the upper touch panel electrodes 121 can be divided into multiple groups, and each group can be paired with a separate lower viewing angle control electrode 126.

[0091] Figure 5A and Figure 5B Schematic illustration along Figure 4 The cross-sectional structure of the touch panel 1 with a controllable viewing angle of the cross-section line VV. Figure 6A and Figure 6B Schematic illustration along Figure 4 The cross-sectional structure of the touch panel 1 with view controllable angle of the section line VI-VI in the middle. Figure 5A and Figure 6A It shows the narrow field of view state. Figure 5B and Figure 6B The wide-view state is shown.

[0092] exist Figure 5A and Figure 6AIn the narrow viewing angle state shown, the electrophoretic particles 140 in each electrophoretic element 114 are dispersed in the dispersion medium 141. The electrophoretic element 114 blocks light from the display panel 5 by absorbing light from the display panel 5 through the dispersed electrophoretic particles 140. Therefore, only light within a narrow emission angle range in the Y-axis direction can pass through the viewing angle controllable touch panel 1.

[0093] In a narrow viewing angle, the upper touch panel electrode 121 and the lower viewing angle control electrode 126, which clamp the electrophoretic element 114, remain at the same potential. Therefore, the electrophoretic particles 140 remain dispersed in the dispersion medium 141. Details of the potential control of the upper touch panel electrode 121, the lower touch panel electrode 123, and the lower viewing angle control electrode 126 will be described later.

[0094] Figure 5B and Figure 6B A view-angle controllable touch panel 1 in a wide-viewing-angle state is shown. The wide-viewing-angle state is achieved by focusing the electrophoretic particles 140 in each electrophoretic element 114 near any of the electrodes that hold the electrophoretic element 114, for example, near the lower view-angle control electrode 126. A large portion of the electrophoretic element 114 is made up of only a transparent dispersion medium 141, making the electrophoretic element 114 transmissive. Therefore, light travels through the view-angle controllable touch panel 1 over a wide range of emission angles in the Y-axis direction.

[0095] In a wide viewing angle, the lower viewing angle control electrode 126 has a relative potential with respect to the upper touch panel electrode 121 that has the opposite polarity to the charge of the electrophoretic particles 140 (potential difference of V). Therefore, the electrophoretic particles 140 aggregate near the lower viewing angle control electrode 126. Figure 5B and Figure 6B In the example, electrophoretic particle 140 carries a negative charge.

[0096] When the electrophoretic particles 140 are negatively charged (-), an appropriate potential is supplied to the downward viewing angle control electrode 126 and the upper touch panel electrode 121 to make the downward viewing angle control electrode 126 a positive electrode. When the electrophoretic particles 140 are positively charged (+), an appropriate potential is supplied to the downward viewing angle control electrode 126 and the upper touch panel electrode 121 to make the downward viewing angle control electrode 126 a negative electrode. For example, a sufficient potential difference V is approximately 10V to 30V.

[0097] Figure 7A and Figure 7B This shows another example of a wide-viewing-angle state in which electrophoretic particles 140 aggregate near the upper touch panel electrode 121. Figure 7A Schematic illustration along Figure 4 The cross-sectional structure of section line VV in the middle. Figure 7B Schematic illustration along Figure 4The cross-sectional structure of section line VI-VI is shown. Electrophoretic particles 140 are negatively charged. The downward viewing angle control electrode 126 and the upper touch panel electrode 121 are supplied with appropriate potential so that the downward viewing angle control electrode 126 becomes a negative electrode.

[0098] The following description is based on the assumption that the electrophoretic particles 140 are negatively charged. In the case that the electrophoretic particles 140 are positively charged, the same control can be applied by changing the polarity of the lower viewing angle control electrode 126 to the opposite polarity.

[0099] The sheet resistance of insulating films 131, 132, and 133 can affect touch sensing and viewing angle control. The inventors' research indicates that more appropriate touch sensing and viewing angle control are achieved when the sheet resistance of these films is between 5E6 Ω / □ and 5E8 Ω / □. When the sheet resistance is below 5E6 Ω / □, touch sensing frequently malfunctions. When the sheet resistance is above 5E12 Ω / □, viewing angle switching takes a long time. A suitable thickness for the insulating films is approximately 10 nm to 100 nm.

[0100] The insulating films 131, 132, and 133 covering the touch panel electrodes 121 and 123 and the lower viewing angle control electrode 126 do not have high insulation properties; they generate a certain intensity of leakage current (soft leakage current) under a strong electric field. Since the insulating films prevent the upper touch panel electrodes 121 and the lower viewing angle control electrode 126 from directly contacting the electrophoretic particles 140, the electrophoretic particles 140 will not adhere to the electrodes.

[0101] Because of its low insulation performance, the electrophoretic particles 140 can be moved without applying a high voltage between the upper touch panel electrode 121 and the lower viewing angle control electrode 126. Therefore, the active light shield achieves high reliability while maintaining high responsiveness. Furthermore, since the insulating film 133 above the lower viewing angle control electrode 126 prevents the electric field between the touch panel electrodes 121 and 123 from being affected by the potential of the lower viewing angle control electrode 126, touch sensing sensitivity can be maintained.

[0102] Figure 8A Another structural example of the view-controllable touch panel 1 is shown. Figure 8A The structural example includes an upper touch panel electrode 121 having a width that is wider than the electrophoretic element (light-shielding area) 114.

[0103] Figure 8B An electrophoretic element 114 with a different shape is shown. The region 145 where electrophoretic particles 140 aggregate can have a narrower width than other regions. Figure 8BIn the example, the end region near the lower viewing angle control electrode 126 has a narrower width than the region above it. When electrophoretic particles 140 aggregate near the upper touch panel electrode 121, this region has a narrower width than the region below it. These configurations provide higher transmittance for the viewing angle-controlled touch panel in narrow viewing angle mode.

[0104] Figure 9 An example configuration of a touch panel electrode group obtained by bundling several adjacent touch panel electrodes is shown. The size of each electrophoretic element 114 and the space between them are designed considering the viewing angle characteristics required by the active light shield. Typically, the size of the electrophoretic element 114 is approximately 3 μm to 100 μm. The space between the electrodes required for touch sensing is approximately 2 mm to 5 mm. The number of electrodes required varies for each function. Specifically, the active light shield requires more electrodes than the touch panel.

[0105] In one embodiment of this specification, the upper touch panel electrode 121 is shared by the touch sensor and the active light shield. Therefore, an equal number of upper touch panel electrode groups as the touch sensor requires are configured by bundling multiple adjacent upper touch panel electrodes 121 together, and each of these groups is connected to a connection terminal 127. Electrodes in an upper touch panel electrode group are supplied with the same potential, and a signal is sent from one upper touch panel electrode group to the touch sensor IC 128.

[0106] exist Figure 9 In the configuration example, the lower touch panel electrode groups are also configured by bundling multiple adjacent lower touch panel electrodes 123, and each of these groups is connected to a connection terminal 129. Electrodes in a lower touch panel electrode group are supplied with the same potential, and a signal is sent from one lower touch panel electrode group to the touch sensor IC 128. A lower touch panel electrode group can be replaced by a single strip-shaped lower touch panel electrode.

[0107] The control of the view-adjustable touch panel 1 is described below. As mentioned above, in addition to the touch panel functions, the view-adjustable touch panel 1 also has a view control function. Figure 10 The relationship between the distance 1 between the upper touch panel electrode 121 and the lower touch panel electrode 123 and the distance 2 between the upper touch panel electrode 121 and the lower viewing angle control electrode 126 is shown.

[0108] In this structure, the distance 1 between the upper touch panel electrode 121 and the lower touch panel electrode 123 is different from the distance 2 between the upper touch panel electrode 121 and the lower viewing angle control electrode 126. Specifically, distance 2 is longer than distance 1.

[0109] When the touch sensing period (the period during which voltage is applied between touch panel electrodes 121 and 123) is long, the electric field differs between the area sandwiched by touch panel electrodes 121 and 123 and the area sandwiched by the upper touch panel electrode 121 and the lower viewing angle control electrode 126. Furthermore, the movement of electrophoretic particles 140 differs between the area above the lower touch panel electrode 123 and other areas (the area above the lower viewing angle control electrode 126). This difference in the movement of electrophoretic particles 140 can be identified as display non-uniformity.

[0110] One embodiment of this specification includes a sensing period and a non-sensing period within a frame time period for touch sensing. During the sensing period, the touch sensor IC 128 supplies signals for touch sensing to the upper touch panel electrode 121, the lower touch panel electrode 123, and the lower viewing angle control electrode 126. During the non-sensing period, the touch sensor IC 128 supplies signals for viewing angle control to the upper touch panel electrode 121, the lower touch panel electrode 123, and the lower viewing angle control electrode 126.

[0111] One embodiment of this specification provides a non-sensing period longer than the sensing period. Therefore, in touch sensing, the effect of the electric field between the touch panel electrodes on the electrophoretic particles 140 (identified display non-uniformity) is reduced.

[0112] A description of capacitive touch sensors is now provided. There are two types of capacitive sensing: self-capacitance sensing and mutual capacitance sensing. A self-capacitance touch sensor has multiple X electrodes and multiple Y electrodes. The X and Y electrodes are arranged in a matrix, with an insulator between them. The self-capacitance touch sensor independently drives the X and Y electrodes to detect changes in capacitance at the electrodes. When an object approaches an electrode, the capacitance of the electrode increases. The self-capacitance sensing detects the increased capacitance of the X and Y electrodes to detect the position of the object.

[0113] A mutual capacitance touch panel has a transmitting electrode (e.g., a Y electrode) as a driving electrode and a receiving electrode (e.g., an X electrode) as a sensing electrode. The driving and sensing electrodes are arranged in a matrix, with an insulator between them. A capacitor (cross capacitor) is disposed at each intersection of the driving and sensing electrodes. When an indicator approaches a cross capacitor, a portion of the electric field at the intersection moves towards the indicator, and the capacitance at the intersection decreases. Mutual capacitance sensing detects which intersection shows the change in mutual capacitance and how large to detect the position of the indicator. The following description is provided using mutual capacitance sensing as an example.

[0114] Figure 11This is a timing diagram showing an example of the change in the potential of the upper touch panel electrode (X electrode) 121, the lower touch panel electrode (Y electrode) 123, and the lower viewing angle control electrode (C electrode) 126 over time in narrow viewing angle mode. Figure 11 The examples in the example include N (N is a natural number) Y electrodes.

[0115] The upper touch panel electrode 121 is the X electrode, which is the receiving electrode (TP-Rx) of the touch sensor and also the control electrode of the viewing angle control device (ALV). The lower touch panel electrode 123 is the Y electrode, which is the transmitting electrode (TP-Tx) of the touch sensor. The lower viewing angle control electrode 126 is the C electrode, which is another control electrode of the viewing angle control device (ALV). The upper touch panel electrode 121 can be a transmitting electrode, and the lower touch panel electrode 123 can be a receiving electrode.

[0116] Assumption Figure 11 The frame rate in the example is 60fps. A frame period is divided into a sensing period and a non-sensing period (ALV main operation period). Although Figure 11 In the example, the non-sensing period follows the sensing period, but this order can be reversed. The sensing period is 2.6 ms, and the non-sensing period is 14 ms. The sensing and non-sensing periods alternate in consecutive frames.

[0117] The Y electrodes are divided into multiple Y electrode groups, each consisting of multiple Y electrodes bundled together. All Y electrodes in a Y electrode group are connected to the same terminal. Assume that all Y electrode groups in this example consist of the same number (e.g., 100) of Y electrodes. Similarly, the X electrodes are divided into multiple X electrode groups, each consisting of multiple X electrodes bundled together.

[0118] During the sensing period, the touch sensor IC 128 supplies a constant potential to all X electrodes, which in this example is 0V. This 0V may be the system ground potential. Additionally, the touch sensor IC 128 selects the Y electrode groups one by one and supplies a drive pulse 311 to the selected group. The potential of the drive pulse is +5V. The potential of unselected Y electrodes or Y electrodes not supplied with a drive pulse is 0V. Y electrodes in the same Y electrode group are supplied with the same drive pulse 311. The touch sensor IC 128 supplies the downward viewing angle control electrode (C electrode) 126 with the same potential as the X electrodes, which is 0V in this example.

[0119] During the non-sensing period, the touch sensor IC 128 supplies a constant potential to all X electrodes, which is 0V in this example. Additionally, the touch sensor IC 128 supplies 0V to all Y electrode groups (all Y electrodes). Since the drive pulse supply to the Y electrodes has been completed during the sensing period, all Y electrodes remain at 0V when transitioning from the sensing period to the non-sensing period. The touch sensor IC 128 supplies the same potential as the X electrodes to the downward viewing angle control electrode (C electrode) 126, which is 0V in this example. The downward viewing angle control electrode (C electrode) 126 remains at 0V throughout both the sensing and non-sensing periods.

[0120] Throughout all periods, the X electrode of the upward touch panel electrode 121 and the C electrode of the downward viewing angle control electrode 126 are supplied with the same potential. Therefore, electrophoretic particles 140 are dispersed within the electrophoretic element 114 to block light from the display panel 5. This means that the viewing angle controllable touch panel 1 is in a narrow viewing angle state.

[0121] Figure 12 Details of the drive pulse 311 used for touch sensing are shown. The drive pulse 311 is a burst signal consisting of multiple consecutive pulses. Figure 12 In the example, the period of the burst signal is 80μs to 150μs, and its frequency is 150kHz to 200kHz. As mentioned above, the sensing period is 2.6ms. The period and frequency of the burst signal can be determined as needed.

[0122] Figure 13 This is a timing diagram illustrating an example of the time-varying potentials of the upper touch panel electrode (X electrode) 121, the lower touch panel electrode (Y electrode) 123, and the lower viewing angle control electrode (C electrode) 126 in wide-viewing-angle mode. (Refer to reference...) Figure 11 Compared to the described timing diagram, the potential change of the X electrode (upper touch panel electrode 121) is different. Specifically, the potential of the X electrode is -20V during non-sensing periods. The potential of the X electrode is 0V during sensing periods, which is the same as the potential in the narrow viewing angle mode. The potential (and its signal) of the other electrodes change over time in the same way as in the narrow viewing angle mode.

[0123] During non-sensing periods, the X electrode or upper touch panel electrode (upper viewing angle control electrode) 121 is supplied with -20V, while the C electrode or lower viewing angle control electrode 126 is supplied with 0V. Therefore, negatively charged electrophoretic particles 140 accumulate in the area closer to the lower viewing angle control electrode 126. This means that the viewing angle controllable touch panel 1 is in a wide viewing angle state.

[0124] Figure 14This is a timing diagram illustrating another example of the time-varying potentials of the upper touch panel electrode (X electrode) 121, the lower touch panel electrode (Y electrode) 123, and the lower viewing angle control electrode (C electrode) 126 in wide-viewing-angle mode. (Refer to reference...) Figure 13 Compared to the timing diagram described, the potential of the X electrode (upper touch panel electrode 121) differs during the sensing period. Specifically, the X electrode is supplied with the same -20V as during the non-sensing period. From a touch sensing perspective, 0V is more preferable than -20V for the potential of the X electrode during the sensing period; Figure 14 The example in the diagram can keep the X electrode at a constant potential.

[0125] In reference Figures 11 to 14 In the described example, the potential of the downward viewing angle control electrode 126 is fixed. This configuration facilitates control of the active sunshade.

[0126] According to reference Figures 11 to 14 The described control divides a frame into a sensing period and a non-sensing period, with the non-sensing period being longer than the sensing period. The non-sensing period occupies 84% ​​of a frame, and the sensing period occupies 16%. This configuration reduces the influence of the electric field between the touch panel electrodes on the electrophoretic particles 140 (recognized display inhomogeneities) during touch sensing.

[0127] The duty cycle between sensing and non-sensing periods is not limited to the examples above.

[0128] The behavior of electrophoretic particles is described. When an electric field E is applied during the time period t, the distance s traveled by the electrophoretic particle can be expressed as follows:

[0129] s = v · t (v: velocity)

[0130] v = μ · E (μ: mobility)

[0131] The mobility of spherical electrophoretic particles can be expressed as follows:

[0132] μ = q / (6π · η · α),

[0133] Where q is the charge, η is the viscosity of the medium, and α is the diameter of the particle.

[0134] Based on the above expression, the distance s traveled by the electrophoretic particle can be represented as follows:

[0135] S = v · t = qEt / (6π · η · α).

[0136] This expression indicates that, among electrophoretic particles with equal charge, those supplied with a stronger electric field or a longer voltage travel further. As mentioned above, setting the non-sensing period to be longer than the sensing period between alternating continuous sensing and non-sensing periods allows the electrophoretic particles to travel further, thereby reducing the occurrence of display non-uniformity.

[0137] Electrophoretic particles 140 have difficulty following voltage changes in a short period of time and are also difficult to move under weak electric fields. During the period when a voltage is applied between the upper touch panel electrode (X electrode) 121 and the lower viewing angle control electrode (C electrode) 126, the electrophoretic particles 140 move gradually. The electrophoretic particles change their state from a dispersed state to a clustered state and vice versa over multiple frame periods. Given this characteristic, the driving method with a short touch sensing period achieves more suitable viewing angle switching without affecting touch sensing.

[0138] Neither the sensing period nor the non-sensing period needs to be constant. However, constant sensing and non-sensing periods are helpful for touch sensing and view control.

[0139] Figures 15A to 15C An example configuration of the receiving circuitry and operation of the X electrode (upper touch panel electrode 121) included in the touch sensor IC 128 is shown. Figures 15A to 15C Each corresponds to a reference. Figure 11 and Figure 13 The state during the described operation. Figure 15A The state during the sensing period is shown. Figure 15B The state is shown during the non-sensing period in narrow-view mode. Figure 15C The state is shown during the non-sensing period in wide-view mode.

[0140] Next, an example of self-capacitive touch sensing will be described. Figure 16 This is a timing diagram illustrating an example of the time-varying potentials of the upper touch panel electrode (X electrode) 121, the lower touch panel electrode (Y electrode) 123, and the lower viewing angle control electrode (C electrode) 126 in narrow viewing angle mode. The X electrodes are divided into groups of 100 electrodes, and the Y electrodes are also divided into groups of 100 electrodes.

[0141] and Figure 11 Timing of narrow-view mode of mutual capacitance touch sensing in Figure 1 Similarly, the touch sensor IC 128 divides a frame into a sensing period and a non-sensing period. The non-sensing period is longer than the sensing period.

[0142] The sensing period includes a pre-defined preparation period starting from the sensing period. During the preparation period provided within the sensing period, the touch sensor IC 128 places all X and Y electrodes in a high-impedance state. Therefore, crosstalk and residual signals from previous scans can be avoided.

[0143] Subsequently, the touch sensor IC 128 selects the X electrode group and the Y electrode group one by one, and applies a sensing pulse voltage 321. Figure 16 The sensor uses a +5V voltage to measure capacitance. The sensing pulse voltage 321 can be a burst signal. When the sensing pulse voltage 321 is applied, the touch sensor IC 128 keeps the unselected X and Y electrodes in a high-impedance state. Keeping the unselected X and Y electrodes in a high-impedance state reduces unwanted current flowing in the parasitic capacitor. During the sensing period, the touch sensor IC 128 supplies 0V (or system ground potential) to the C electrode.

[0144] During non-sensing periods, the touch sensor IC 128 supplies 0V (or system ground potential) to all X, Y, and C electrodes. Since the X and C electrodes are at the same potential, the electrophoretic particles 140 are dispersed. This means that the view-angle controllable touch panel 1 is in a narrow viewing angle state.

[0145] Figure 17 This is a timing diagram illustrating an example of the time-varying potentials of the upper touch panel electrode (X electrode) 121, the lower touch panel electrode (Y electrode) 123, and the lower viewing angle control electrode (C electrode) 126 in wide viewing angle mode. Figure 16 Compared to the timing diagram in the narrow-angle mode, the potential of the X electrode differs during the non-sensing period. Specifically, the potential of the X electrode during the non-sensing period is +20 V. Since the potential of the lower-angle control electrode (C electrode) 126 is fixed at 0 V, a force is applied to the negatively charged electrophoretic particles 140, causing them to aggregate toward the X electrode.

[0146] The description of the relationship between the sensing period, the non-sensing period, and a frame period in mutual capacitance sensing applies to this self-capacitance sensing.

[0147] As described above, one embodiment of this specification integrates some electrodes of the touch sensor (upper touch panel electrode 121) with the viewing angle control device to reduce the thickness of the viewing angle control device (active light shield). Furthermore, a lower viewing angle control electrode (C electrode) 126 with a large area is used to control the behavior of the electrophoretic particles 140 to generate a more uniform electric field, enabling the viewing angle control device to operate uniformly within a plane.

[0148] One embodiment of this specification employs a time series with a short touch sensing period. The short touch sensing period reduces the influence of the electric field on the electrophoretic particles 140 during the touch sensing period, while the long non-sensing period for applying the electric field for viewing angle control suppresses the uneven dispersion of the electrophoretic particles 140 after switching viewing angle characteristics. In one embodiment of this specification, the potential of the upper touch panel electrode 121 for viewing angle control is changed only when switching between wide and narrow viewing angles. This configuration facilitates control.

[0149] The following describes an example of a method for manufacturing a display device including a viewing angle-controlled touch panel 1. This method is an example; the display device can be manufactured by any other method.

[0150] Reference Figure 18A The manufacturing method involves depositing a metal film 301 on an upper glass substrate 112, and further depositing an insulating film 302 on top of the metal film 301.

[0151] Next, refer to Figure 18B The manufacturing method involves patterning the metal film 301 and the insulating film 302 together by applying photoresist, exposure, development, and etching. Thus, the pattern of the upper touch panel electrode 121 and the insulating film 131 is formed on the upper glass substrate 112.

[0152] Next, refer to Figure 18C The manufacturing method involves applying a photosensitive permanent film 303 onto an upper glass substrate 112 to cover the upper touch panel electrode 121 and the insulating film 131, and pre-baking them.

[0153] Next, refer to Figure 18D This manufacturing method uses the upper touch panel electrode 121 as a mask to expose and develop the photosensitive permanent film 303 to form a transparent area (transparent area) 115. Through this step, the upper substrate is completed. The transparent area 115 can be formed using nanoimprint lithography instead of photolithography.

[0154] Next, refer to Figure 18E This manufacturing method forms a lower viewing angle control electrode 126, an insulating film 133, a lower touch panel electrode 123, and an insulating film 132. Through this step, the lower substrate is completed.

[0155] This step involves depositing a metal film for the lower viewing angle control electrode 126 and an insulating film thereon, and forming the lower viewing angle control electrode 126 and the insulating film 133 by applying photoresist, exposure, development, and etching. Additionally, this step involves depositing a metal film for the lower touch panel electrode 123 and an insulating film thereon, and forming a pattern of the lower touch panel electrode 123 and the insulating film 132 by applying photoresist, exposure, development, and etching.

[0156] Next, refer to Figure 18F This manufacturing method involves bonding an upper substrate and a lower substrate together by heating and pressurizing to create a viewing angle-controlled touch panel 1. In this process, the method electrically connects terminals on the upper substrate and terminals on the lower substrate, for example, using an anisotropic conductive film (ACF). Next, referring to… Figure 18G This manufacturing method involves injecting electrophoretic element material into the space between the transparent regions 115. Next, refer to... Figure 18H This manufacturing method involves bonding the viewing angle controllable touch panel 1 to the display panel 5.

[0157] An example of the layout of the electrophoretic element 114 is described. Figure 19 An example layout of the electrophoretic elements 114 is shown. In this layout, the electrophoretic elements 114 have a columnar shape and are arranged in an alternating manner. More specifically, rows of electrophoretic elements are located below the upper touch panel electrode 121, and each row consists of electrophoretic elements 114 arranged in the X-axis direction and spaced apart from each other. Each electrophoretic element 114 is controlled by the upper touch panel electrode 121 and the lower viewing angle control electrode 126.

[0158] In each row, the electrophoretic elements 114 are arranged at equal intervals. The electrophoretic elements 114 in two consecutive rows are staggered in the Y-axis direction. That is, when viewed along the Y-axis direction, each electrophoretic element 114 is located between adjacent electrophoretic elements 114 in each of the two adjacent rows. This layout enables viewing angle control in both the X-axis and Y-axis directions.

[0159] Implementation Method 2

[0160] Figure 20 This specification schematically illustrates a structural example of a display device according to another embodiment. Main description and... Figure 1 The structural examples differ from those in the reference. Unless otherwise stated, the materials and dimensions of the parts may differ from those in the reference. Figure 1 The components are of the same type and size as those described in the other accompanying drawings. The display device includes a display panel 5 and a viewing angle-controlled touch panel 7 disposed on the front of the display panel 5. The configuration of the display panel 5 is the same as... Figure 1 The configuration of display panel 5 is the same.

[0161] A viewing angle-controlled touch panel 7 is in direct contact with and positioned above the thin-film encapsulation structure 53. The thin-film encapsulation structure 53 is a multilayer encapsulation film used to protect OLED elements from oxygen and moisture. The thin-film encapsulation structure 53 may include alternating layers of inorganic and organic materials, or may include only inorganic or organic material layers. Examples of inorganic materials include silicon nitride (SiNx) and aluminum oxide (Al2O3), while examples of organic materials include acrylic resin. The thin-film encapsulation structure 53 may consist of two silicon nitride layers and an organic material layer between them; it may also include additional inorganic and / or organic material layers.

[0162] The viewing angle controllable touch panel 7, starting from the bottom, includes, in sequence, an emitting electrode (TP-Tx) 723, an insulating film 731, a receiving electrode (TP-Rx) 726, another insulating film 732, an electrophoretic element 714, an upper light-shielding electrode 721, and a polyimide substrate 712. The upper light-shielding electrode 721, the emitting electrode 723, and the receiving electrode 726 are electrically insulated from each other. The upper light-shielding electrode 721 is the upper viewing angle control electrode. The positions of the emitting electrode 723 and the receiving electrode 726 can be interchanged.

[0163] The viewing angle-controlled touch panel 7 is directly positioned above the thin-film encapsulation structure 53. In other words, it eliminates the need for... Figure 1 The lower glass substrate 111 in the structural example. (And...) Figure 1 Compared to the structural example in the previous example, the cover glass 33 is omitted, and a flexible polyimide substrate 712 is provided to replace the upper glass substrate 112.

[0164] The polyimide substrate 712 and the circular polarizer 62 are tightly bonded together by an adhesive layer 63 disposed therebetween. The adhesive layer 63 may be made of resin. Although the following description is an example of the structure of a mutual capacitance touch panel, the structure of a self-capacitance touch panel may also be employed.

[0165] Multiple electrophoretic elements 714 are disposed between the thin-film encapsulation structure 53 and the polyimide substrate 712. Multiple upper light-shielding electrodes 721 are disposed between the bottom surface of the polyimide substrate 712 and the electrophoretic elements 714; each upper light-shielding electrode 721 is opposite to the electrophoretic element 714 to control the dispersion state of the electrophoretic particles. An insulating film 731 is disposed between the electrophoretic elements 714 and the upper light-shielding electrodes 721.

[0166] The state of the electrophoretic particles in the electrophoretic element 714 is controlled by the electric field between the upper light-shielding electrode 721 of the touch panel and the receiving electrode (TP-Rx) 726. The receiving electrode 726 is also the lower viewing angle control electrode.

[0167] The viewing angle adjustable touch panel 7 has the same characteristics as... Figure 1The viewing angle controllable touch panel 7 has different electrode structures. The viewing angle controllable touch panel 7 includes multiple emitting electrodes 723 directly disposed above the thin-film encapsulation structure 53, an insulating film 731 covering the emitting electrodes 723, multiple receiving electrodes 726 disposed above the insulating film 731, and another insulating film 732 covering the insulating film 731 and the receiving electrodes 726. The emitting electrodes 723 and the receiving electrodes 726 are electrodes used in mutual capacitance touch panels. Another insulating film can be disposed between the emitting electrodes 723 and the thin-film encapsulation structure 53.

[0168] Figure 21 An example of the electrode layout of the viewing angle controllable touch panel 7 is shown. Figure 21 The layout shown is merely an example; other layouts may be used. The potential of the upper light-shielding electrode 721 is controlled by a light-shielding controller 728 included in the controller. The potentials of the emitting electrode 723 and the receiving electrode 726 are controlled by a touch panel controller (not shown) included in the controller. The touch panel controller measures the capacitance change between the electrodes to detect the touch point of the indicator based on the measurement results.

[0169] exist Figure 21 In the configuration example, the upper light-shielding plate electrodes 721 are X electrodes, and they are configured to extend in the X-axis direction and be spaced apart from each other in the Y-axis direction. The width of the upper light-shielding plate electrodes 721 and their spacing can be uniform or different. The upper light-shielding plate electrodes 721 can have a shape such as a rectangular strip, but the shape is not particularly limited.

[0170] The emitting electrodes 723 are X-electrodes, and they are configured to extend in the X-axis direction and be spaced apart from each other in the Y-axis direction. The spacing of the emitting electrodes 723 can be uniform or varied. The emitting electrodes 723 can have, for example... Figure 21 The shape shown is one in which a wide rhomboid (rectangular) region is connected by a narrow strip-shaped joining region, or other shapes such as rectangular strip shapes.

[0171] The receiving electrodes 726 are Y electrodes, and they are configured to extend in the Y-axis direction and be spaced apart from each other in the X-axis direction. The spacing of the receiving electrodes 726 can be uniform or varied. The receiving electrodes 726 can have, for example... Figure 21 The shape shown connects wide rhomboid (rectangular) regions through narrow strip-shaped joining regions, or other shapes such as rectangular strips. Figure 21 In the configuration example, the bonding region of the transmitting electrode 723 overlaps with the bonding region of the receiving electrode 726 in the stacking direction, and the wide region of the transmitting electrode 723 is away from the wide region of the receiving electrode 726 and does not overlap with each other.

[0172] Figure 22This is a timing diagram illustrating an example of the time-varying potentials of the upper light-shielding electrode 721, the emitting electrode (TP-Tx) 723, and the receiving electrode (TP-Rx) 726 in narrow viewing angle mode. Figure 11 Compared to the timing diagram, the potential change over time of the upper light-shielding electrode 721 is the same as that of the X electrode (TP-Rx, ALV). The potential change over time of the emitting electrode (TP-Tx) 723 is the same as that of the Y electrode (TP-Tx). The potential change over time of the receiving electrode (TP-Rx) 726 is the same as that of the C electrode. (See reference...) Figure 11 and Figure 12 The driving pulse of the transmitting electrode 723 used for touch sensing is a burst signal.

[0173] Figure 23 This is a timing diagram illustrating an example of the time-varying potentials of the upper light-shielding electrode 721, the emitting electrode (TP-Tx) 723, and the receiving electrode (TP-Rx) 726 in wide-viewing-angle mode. Figure 22 Compared to the timing diagram, the potential change of the upper light-shielding electrode 721 is different. During the non-sensing period, the potential of the upper light-shielding electrode 721 is -20V. During the sensing period, the potential of the upper light-shielding electrode 721 is 0V, which is the same as the potential under narrow viewing angle conditions. The potential (signal) changes of the other electrodes over time are the same as the potential (signal) changes over time under narrow viewing angle conditions.

[0174] During non-sensing periods, the upper light-shielding electrode 721 is supplied with -20V, while the receiving electrode (TP-Rx) 726 and the emitting electrode (TP-Tx) 723, which can be used as lower viewing angle control electrodes, are supplied with 0V. Therefore, negatively charged electrophoretic particles accumulate in the area closer to the receiving electrode (TP-Rx) 726. This means the viewing angle controllable touch panel 7 is in a wide viewing angle state. By supplying a positive potential (e.g., +20V) to the upper light-shielding electrode 721 during non-sensing periods, negatively charged electrophoretic particles can accumulate in the area closer to the upper light-shielding electrode 721.

[0175] Figure 24 and Figure 25 Another structural example of the transmitting electrode pattern and the receiving electrode pattern is shown. Figure 24 It is a cross-sectional view. Figure 25 This is a floor plan. Main descriptions and references. Figure 20 and Figure 21 The structural examples described differ. The view-controllable touch panel 71 includes multiple transmitting electrodes 743 and multiple receiving electrodes 746.

[0176] The emitter electrode 743 and the receiver electrode 746 are disposed directly above the thin-film encapsulation structure 53. More specifically, the entire area of ​​the emitter electrode 743 and the diamond-shaped wide area of ​​the receiver electrode 746 are disposed directly above the thin-film encapsulation structure 53. The bonding area of ​​the receiver electrode 746 is disposed above the insulating film 751 covering the wide area of ​​the receiver electrode 746; each bonding area extends through the insulating film 751 to two adjacent wide areas and connects them.

[0177] The wide region and bonding region of the emitter electrode 743 are directly disposed above the thin-film encapsulation structure 53. The wide region of the receiver electrode 746 is also directly disposed above the thin-film encapsulation structure 53. These components are all contained within the same metal layer. The wide regions and bonding regions of the emitter electrode 743 and the wide region of the receiver electrode 746 are covered by an insulating film 751. The wide regions of the emitter electrode 743 and the receiver electrode 746 are physically separated; the space between them is filled by a portion of the insulating film 751.

[0178] The bonding regions of the receiving electrode 746 are disposed on the insulating film 751, and each bonding region extends through a hole in the insulating film 751 to reach two adjacent wide regions of the receiving electrode 746. Therefore, the adjacent wide regions are connected and electrically linked. Although the bonding regions of the receiving electrode 746 overlap with the bonding regions of the transmitting electrode 743 in the stacking direction, the insulating film 751 lies between them, thus they are physically separated. Due to this structure, the transmitting electrode 743 and the receiving electrode 746 are electrically insulated.

[0179] The insulating film 751 and the bonding area of ​​the receiving electrode 746 above it are both covered by the insulating film 752. Multiple electrophoretic elements 714 are disposed above the insulating film 752. The emitting electrode 743 and the receiving electrode 746 can have any structure, as long as they are configured to avoid contact between the emitting electrode 743 and the receiving electrode 744. For example, the structural relationship between the emitting electrode 743 and the receiving electrode 746 can be as follows: Figure 24 and Figure 25 The relationships in the structural example shown are reversed.

[0180] Figure 26 This is a flowchart illustrating an example of a method for manufacturing a display device, the display device comprising, as shown in the reference... Figure 20 and Figure 21 ,or Figure 24 and Figure 25 The described configuration example is a viewing angle-controlled touch panel located directly above the thin-film encapsulation structure 53. As described above, no substrate is interposed between the thin-film encapsulation structure 53 and the electrodes used for touch sensing and viewing angle control.

[0181] The method for manufacturing the display device involves forming an emitter electrode and a receiver electrode on a thin-film encapsulation structure 53, forming an upper light-shielding electrode and a space for injecting electrophoretic element material into a transparent insulating film on a polyimide substrate opposite to the thin-film encapsulation structure 53, separated by an electrode pattern layer and an electrophoretic element, bonding the thin-film encapsulation structure and the polyimide substrate together, and injecting the electrophoretic element material into the space. As described above, the electrophoretic element material consists of electrophoretic particles 140 and a dispersion medium 141. For the method of forming each pattern layer, refer to... Figures 18A to 18H The provided description is applicable.

[0182] Reference Figure 26 The manufacturing method forms a pattern of an emitter electrode (TP-Tx), a pattern of a receiver electrode (TP-Rx), and an insulating film on a thin-film encapsulation structure (S31). For example, an insulating film is disposed between the emitter electrode pattern and the receiver electrode pattern, and another insulating film is disposed to cover them. There are no limitations on the multilayer structure including the emitter electrode, the receiver electrode, and one or more insulating films, unless the functions of touch sensing and viewing angle control are impaired.

[0183] In addition, this manufacturing method forms a pattern of upper light-shielding electrodes on a polyimide substrate (S35), and applies a photosensitive permanent film as the material for the light-transmitting area on the polyimide substrate having the upper light-shielding electrodes, and pre-baks them (S36). This manufacturing method uses the pattern of the upper light-shielding electrodes as a mask, and exposes and develops the photosensitive permanent film by photolithography to form transparent areas (light-transmitting areas). Through this process, transparent areas between electrophoretic elements are formed (S37). The transparent areas can be formed using nanoimprint lithography instead of photolithography.

[0184] The manufacturing method involves bonding a component, including a thin-film encapsulation structure and its electrode pattern, to a component including a polyimide substrate, an upper light-shielding electrode, and transparent areas by heating and pressing (S41). Next, the manufacturing method injects electrophoretic element material into the space formed between the transparent areas (S42) and bonds a circular polarizing plate to the side of the polyimide substrate opposite to the electrophoretic element (S43). Through the above steps, the manufacturing of the device is completed.

[0185] As described above, embodiments of the present invention have been presented; however, the present invention is not limited to the embodiments described above. Those skilled in the art can readily modify, add to, or transform each element in the above embodiments within the scope of the present invention. A portion of the configuration of one embodiment can be replaced by the configuration of another embodiment, or the configuration of one embodiment can be incorporated into the configuration of another embodiment.

Claims

1. A viewing angle controllable touch panel device, comprising: Top transparent substrate; Lower transparent substrate; A lower viewing angle control electrode is provided on the top surface of the lower transparent substrate. Multiple lower touch panel electrodes, the multiple lower touch panel electrodes being located on the top surface of the lower transparent substrate; Multiple upper touch panel electrodes, the multiple upper touch panel electrodes being located on the bottom surface of the upper transparent substrate; as well as A plurality of electrophoretic elements are disposed between the bottom surface of the upper transparent substrate and the top surface of the lower transparent substrate. Each of the plurality of electrophoretic elements includes electrophoretic particles and a dispersion medium. The plurality of lower touch panel electrodes are contained in a layer above the lower viewing angle control electrodes. In the plan view, each of the plurality of lower touch panel electrodes at least partially overlaps with the lower viewing angle control electrode. Each of the plurality of electrophoretic elements is sandwiched between one of the plurality of upper touch panel electrodes and the lower viewing angle control electrode.

2. The viewing angle controllable touch panel device according to claim 1 further includes: Controller The controller is configured to control the potentials of the plurality of upper touch panel electrodes, the plurality of lower touch panel electrodes, and the potential of the lower viewing angle control electrode. The controller is configured to control the potential during alternating sensing and non-sensing periods. The controller is configured to perform touch sensing during the sensing period by controlling the potentials of the plurality of upper touch panel electrodes and the plurality of lower touch panel electrodes. The controller is configured to control the state of electrophoretic particles in the plurality of electrophoretic elements by controlling the potentials of the plurality of upper touch panel electrodes and the potential of the lower viewing angle control electrode during the non-sensing period, thereby achieving viewing angle control. The non-sensing period is longer than the sensing period.

3. The viewing angle controllable touch panel device according to claim 2, wherein, The controller is configured to: The lower viewing angle control electrode is maintained at a constant potential during the sensing period and the non-sensing period; as well as During the non-sensing period, a potential for the viewing angle control is supplied to the plurality of upper touch panel electrodes, and the same potential as the lower viewing angle control electrode is supplied to the lower touch panel electrodes.

4. The viewing angle controllable touch panel device according to claim 2, wherein, The controller is configured to: The lower viewing angle control electrode is maintained at a constant potential during the sensing period and the non-sensing period; During the sensing period, the plurality of upper touch panel electrodes are maintained at a constant potential, and the plurality of lower touch panel electrodes are selected one by one to supply a drive signal to the selected lower touch panel electrode. During the non-sensing period, a potential for the viewing angle control is supplied to the plurality of upper touch panel electrodes, and the same potential as the lower viewing angle control electrode is supplied to the lower touch panel electrodes.

5. The viewing angle controllable touch panel device according to claim 1, further comprising: A first insulating film, each first insulating film being disposed between the upper touch panel electrode and the electrophoretic element material composed of the electrophoretic particles and the dispersion medium; A second insulating film is disposed between the lower touch panel electrode and the electrophoretic element material; as well as A third insulating film is disposed between the lower viewing angle control electrode and the lower touch panel electrode. The sheet resistance of the first insulating film, the second insulating film, and the third insulating film ranges from 5E6Ω / □ to 5E8Ω / □.

6. The viewing angle controllable touch panel device according to claim 1, wherein, In the plan view, the lower viewing angle control electrode is opposite to all electrophoretic elements disposed between the upper transparent substrate and the lower transparent substrate.

7. A display device, comprising: Display panel; as well as A viewing angle controllable touch panel device according to any one of claims 1 to 6 is disposed on the front of the display panel.

8. A display device, comprising: Display panel; as well as The viewing angle controllable touch panel device according to claim 2, Each frame period includes the sensing period and the non-sensing period.

9. A display device, comprising: OLED display panel; A viewing angle controllable touch panel device is installed on the OLED display panel; as well as Controller The view-controllable touch panel device includes: Multiple top-view control electrodes; A plurality of first touch panel electrodes and a plurality of second touch panel electrodes, wherein the plurality of first touch panel electrodes and the plurality of second touch panel electrodes are disposed on the thin-film encapsulation structure of the OLED display panel without a substrate therebetween; and Multiple electrophoretic elements are disposed between multiple upper viewing angle control electrodes and a touch panel electrode array. The touch panel electrode array includes multiple first touch panel electrodes and multiple second touch panel electrodes in the stacking direction. Each electrophoretic element includes electrophoretic particles and a dispersion medium. The controller is configured to control the potential of the plurality of upper viewing angle control electrodes. The controller is configured to control the potential during alternating sensing and non-sensing periods. The controller is configured to perform touch sensing during the sensing period by controlling the potentials of the plurality of first touch panel electrodes and the plurality of second touch panel electrodes. The controller is configured to control the viewing angle during the non-sensing period by controlling the state of electrophoretic particles in the plurality of electrophoretic elements using the electric field between the plurality of upper viewing angle control electrodes and the plurality of first touch panel electrodes and the plurality of second touch panel electrodes, thereby achieving viewing angle control. The non-sensing period is longer than the sensing period.

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