Pixel structure

Abstract

The invention provides a pixel structure. The pixel structure comprises a substrate, a micro light emitting diode and an electrophoresis structure. The micro light-emitting diode is arranged on the substrate and emits light. The electrophoresis structure is arranged on the micro light-emitting diode and comprises an upper electrode, a lower electrode, an electrophoresis medium and an electrophoresis lens. The upper electrode and the lower electrode form an electric field. The electrophoretic medium is arranged between the upper electrode and the lower electrode, and the electrophoretic medium has a first refractive index. The electrophoretic lens is disposed in the electrophoretic medium and has a second refractive index, and the second refractive index is different from the first refractive index. The electrophoretic lens is driven by the electric field to be far away from or close to the micro light emitting diode, so that the light penetrating through the electrophoretic lens has a first light emitting field angle or a second light emitting field angle after being refracted, and the first light emitting field angle is different from the second light emitting field angle.

Description

Technical Field

[0001] The present invention relates to a pixel structure, and in particular to a pixel structure capable of adjusting a light emitting angle. Background Art

[0002] With the widespread application of electronic devices, people's requirements for electronic devices are gradually increasing. For example, existing display devices usually provide display images to users located directly in front of them. In other words, for users located diagonally in front of the display device, the user experience is easily affected by the insufficient light angle of the display device. Therefore, although the pixel structures of existing display devices have gradually met their intended uses, they do not meet the requirements in all aspects. Therefore, there are still some problems to be overcome regarding the pixel structure. Summary of the invention

[0003] In some embodiments, a pixel structure is provided. The pixel structure includes a substrate, a micro-light emitting diode and an electrophoretic structure. The micro-light emitting diode is disposed on the substrate and emits light. The electrophoretic structure is disposed on the micro-light emitting diode and includes an upper electrode and a lower electrode, an electrophoretic medium and an electrophoretic lens. The upper electrode and the lower electrode form an electric field. The electrophoretic medium is disposed between the upper electrode and the lower electrode, wherein the electrophoretic medium has a first refractive index. The electrophoretic lens is disposed in the electrophoretic medium and has a second refractive index, and the second refractive index is different from the first refractive index. The electrophoretic lens is driven by the electric field to generate an electrostatic force to move away from or close to the micro-light emitting diode, so that the light passing through the electrophoretic lens has a first light emitting angle or a second light emitting angle after refraction, and the first light emitting angle is different from the second light emitting angle.

[0004] In some embodiments, a pixel structure is provided. The pixel structure includes a substrate, a first micro-LED, a second micro-LED, a first electrophoretic structure, a second electrophoretic structure and an electrochromic structure. The first micro-LED and the second micro-LED are disposed on the substrate and emit a first light and a second light having the same color, respectively. The first electrophoretic structure and the second electrophoretic structure are disposed on the first micro-LED and the second micro-LED, respectively. The first electrophoretic structure and the second electrophoretic structure include an upper electrode, a lower electrode, an electrophoretic medium and an electrophoretic lens, respectively. The upper electrode and the lower electrode form an electric field. The electrophoretic medium is disposed between the upper electrode and the lower electrode, wherein the electrophoretic medium has a first refractive index. The electrophoretic lens is disposed in the electrophoretic medium, wherein the electrophoretic lens has a second refractive index, and the second refractive index is different from the first refractive index. The electrochromic structure is disposed between the first electrophoretic structure and the second electrophoretic structure, and selectively switches between a transparent state and an opaque state, wherein the opaque state is used to shield the first light and the second light in a partial direction. The electrophoretic lens of the first electrophoretic structure is driven by the electric field to generate an electrostatic force to move away from or approach the first micro-light emitting diode, so that the first light passing through the first electrophoretic structure has a first light-emitting angle or a second light-emitting angle after refraction, and the first light-emitting angle is different from the second light-emitting angle. The electrophoretic lens of the second electrophoretic structure is driven by the electric field to generate an electrostatic force to move away from or approach the second micro-light emitting diode, so that the second light passing through the second electrophoretic structure has a third light-emitting angle or a fourth light-emitting angle after refraction, and the third light-emitting angle is different from the fourth light-emitting angle.

[0005] The pixel structure of the present disclosure can be applied to various types of electronic devices. To make the features and advantages of the present disclosure more obvious and easy to understand, various embodiments are given below and described in detail with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0006] Through the following detailed description in conjunction with the attached drawings, the viewpoints of the embodiments of the present disclosure can be better understood. It is worth noting that, according to standard practices in the industry, some components may not be drawn to scale. In fact, the sizes of different components may be increased or reduced in order to clearly describe.

[0007] Figure 1 is a schematic diagram showing a pixel structure according to some embodiments of the present disclosure;

[0008] Figure 2 is a schematic diagram showing a pixel structure according to other embodiments of the present disclosure;

[0009] Figure 3 is a schematic diagram showing a pixel structure according to some other embodiments of the present disclosure;

[0010] Figure 4 is a schematic diagram showing a pixel structure according to some other embodiments of the present disclosure;

[0011] Figure 5 is a schematic diagram showing a pixel structure according to some other embodiments of the present disclosure;

[0012] Figure 6 is a schematic diagram showing a pixel structure according to some other embodiments of the present disclosure;

[0013] Figure 7 is a schematic diagram showing a convergence mode of a pixel structure according to some embodiments of the present disclosure;

[0014] Figure 8 is a schematic diagram showing a convergence mode of a display device according to some embodiments of the present disclosure;

[0015] Fig. 9 is a schematic diagram showing a divergent mode of a pixel structure according to some embodiments of the present disclosure;

[0016] Fig.10 is a schematic diagram showing a divergent mode of a display device according to some embodiments of the present disclosure;

[0017] Fig.11 is a schematic diagram showing a convergence mode of a pixel structure according to some other embodiments of the present disclosure;

[0018] Fig.12 Schematic diagrams showing divergent modes of pixel structures according to other embodiments of the present disclosure.

[0019]

Explanation of symbols

[0020] 1: Pixel structure

[0021] 10:Substrate

[0022] 11,11a~11h: Micro light emitting diode

[0023] 11X: The first micro-LED

[0024] 11Y: Second micro-light emitting diode

[0025] 12: Electrophoretic structure

[0026] 12X: First electrophoretic structure

[0027] 12Y: Second electrophoretic structure

[0028] 120,120X,120Y: Upper electrode

[0029] 121,121X,121Y: Lower electrode

[0030] 122,122X,122Y: Electrophoresis medium

[0031] 123,123a~123h,123X,123Y: electrophoresis lens

[0032] 1230: first sub-lens

[0033] 1231: Second sub-lens

[0034] 13: Electrochromic structure

[0035] 2: Pixel structure

[0036] DS: Display Device

[0037] f: focal length

[0038] IL: Axis

[0039] ML: Middle Layer

[0040] OL: Outer layer

[0041] S1~S12: Status

[0042] θ1: first light emitting angle

[0043] θ2: Second light emitting angle

[0044] θ3: The third luminous angle

[0045] θ4: fourth light emitting angle DETAILED DESCRIPTION

[0046] The following disclosure provides many different embodiments or examples for implementing the provided pixel structure and its formation method. Specific examples of each component and its configuration are described below to simplify the embodiments of the present disclosure, and are certainly not intended to limit the present disclosure. For example, if the description mentions that a first component is formed on a second component, it may include an embodiment in which the first component and the second component are in direct contact, and it may also include an embodiment in which an additional component is formed between the first component and the second component so that the first component and the second component are not in direct contact. In addition, the present disclosure may repeat component symbols and / or characters in different embodiments or examples. Such repetition is for simplicity and clarity, and is not used to indicate the relationship between the different embodiments and / or examples discussed.

[0047] In some embodiments of the present disclosure, terms such as "disposed", "connected" and the like, unless otherwise defined, may refer to two components being in direct contact, or may refer to two components not being in direct contact, wherein an additional component is located between the two structures. Terms such as "disposed", "connected" and the like may also include situations where both structures are movable or both structures are fixed.

[0048] In addition, the terms "first", "second" and similar terms mentioned in this specification or claims are used to name different components or distinguish different embodiments or ranges, and are not used to limit the upper or lower limit of the number of components, nor are they used to limit the manufacturing order or setting order of the components.

[0049] In this article, the terms "approximate", "about", and "substantially" generally mean within 10%, or within 5%, or within 3%, or within 2%, or within 1%, or within 0.5% of a given value or range. The number given here is an approximate number, that is, in the absence of specific instructions for "about", "approximately", or "substantially", the meaning of "about", "approximately", or "substantially" can still be implied. The term "range is between a first value and a second value" means that the range includes the first value, the second value, and other values ​​between them. Furthermore, any two values ​​or directions used for comparison may have a certain error. If the first value is equal to the second value, it implies that there may be an error of about 10%, or within 5%, or within 3%, or within 2%, or within 1%, or within 0.5% between the first value and the second value. If the first direction is perpendicular to the second direction, the angle between the first direction and the second direction may be between 80 degrees and 100 degrees. If the first direction is parallel to the second direction, the angle between the first direction and the second direction may be between 0 degrees and 10 degrees.

[0050] Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meanings as commonly understood by those skilled in the art. It is understood that these terms, such as those defined in commonly used dictionaries, should be interpreted as having a meaning consistent with the background or context of the relevant technology and the present disclosure, and should not be interpreted in an idealized or overly formal manner unless specifically defined in the embodiments of the present disclosure.

[0051] It should be understood that for the sake of clarity, some components of the device are omitted in the drawings and only some components are schematically shown. In some embodiments, additional components may be added to the device described below. In other embodiments, some components of the device described below may be replaced or omitted. It should be understood that in some embodiments, additional operating steps may be provided before, during and / or after the method of forming the device. In some embodiments, some of the operating steps described may be replaced or omitted, and the order of some of the operating steps described is interchangeable.

[0052] In the prior art, a pixel structure may include a light-emitting diode (LED) and a functional layer thereon. For example, the light-emitting diode may be a micro light-emitting diode (micro LED) or other suitable light-emitting diode, and the functional layer may be or may include a filter, an anti-reflection layer, a light-guiding layer, a combination thereof, or other suitable functional layers, but the present disclosure is not limited thereto. However, these pixel structures only have a single light-emitting angle, which limits the application of display devices.

[0053] To this end, the present disclosure provides a pixel structure that can adjust the light emission angle of light so that the displayed image can correspond to users at different viewing positions (for example, directly in front or diagonally in front). In some cases, a display device using this pixel structure can also display different display images at the same time, each corresponding to a user located on both sides of the display device. For example, a car display device can display different display images to the driver's seat and the co-pilot seat of a car in a single display area to provide a better user experience. It is worth mentioning that the different display images described in the present disclosure are presented according to the viewing angle, rather than the split screen in the prior art.

[0054] Reference Figure 1 , which is a schematic diagram showing a pixel structure according to some embodiments of the present disclosure. In these embodiments, the pixel structure 1 can be used as a single sub-pixel, and a plurality of sub-pixels (e.g., a red sub-pixel, a blue sub-pixel, and a green sub-pixel) can constitute a pixel. As shown in the figure, the pixel structure 1 includes a substrate 10, and the substrate 10 carries electronic components located thereon (e.g., a micro-light emitting diode 11 and an electrophoretic structure 12 to be mentioned below). In some embodiments, the substrate 10 may be a printed circuit board (PCB), a thin film transistor glass (TFT glass), a complementary metal oxide semiconductor (CMOS) substrate, or other suitable substrate, but the present disclosure is not limited thereto.

[0055] like Figure 1As shown, the pixel structure 1 also includes a micro light-emitting diode (μLED) 11, which emits light. For example, the micro light-emitting diode 11 may be a green LED chip, and the green LED chip emits green visible light with a wavelength between 495nm and 570nm. Alternatively, the micro light-emitting diode 11 may be a red LED chip, and the red LED chip emits red visible light with a wavelength between 620nm and 750nm. Alternatively, the micro light-emitting diode 11 may be a blue LED chip, and the blue LED chip emits blue visible light with a wavelength between 450nm and 495nm. However, the present disclosure is not limited to the above three colors of LED chips. In other embodiments, the micro light-emitting diode 11 may also be an LED chip of other colors.

[0056] like Figure 1 As shown, the pixel structure 1 further includes an electrophoretic structure 12, which is disposed on the micro-LED 11. Specifically, the electrophoretic structure 12 adjusts the light emission angle of the light emitted by the micro-LED 11 to achieve some advantageous effects as described above.

[0057] In some embodiments, the electrophoretic structure 12 includes an upper electrode 120 and a lower electrode 121, and the upper electrode 120 and the lower electrode 121 are disposed on the micro-light emitting diode 11. Specifically, the upper electrode 120 and the lower electrode 121 form a specific electric field, and the specific electric field can be used to drive the electrophoretic lens 123 located therein (described in detail below). In some embodiments, the upper electrode 120 and the lower electrode 121 may be or may include a transparent conductive oxide (TCO). For example, the transparent conductive oxide may be or may include indium tin oxide (ITO), antimony zinc oxide (AZO), tin oxide (SnO), zinc oxide (ZnO), indium zinc oxide (IZO), indium gallium zinc oxide (IGZO), indium tin zinc oxide (ITZO), antimony tin oxide (ATO), combinations thereof or other suitable transparent conductive materials, but the present disclosure is not limited thereto. In some embodiments, the material of the upper electrode 120 and the material of the lower electrode 121 may be similar or the same, but the present disclosure is not limited thereto.

[0058] In some embodiments, the electrophoretic structure 12 further includes an electrophoretic medium 122, and the electrophoretic medium 122 is disposed between the upper electrode 120 and the lower electrode 121. Specifically, the electrophoretic medium 122 serves as a medium in which the electrophoretic lens 123 (described in detail below) can move. In some embodiments, the electrophoretic medium 122 may be a colorless fluid that is completely or partially transparent. For example, the electrophoretic medium 122 may be or may include: hydrocarbons, such as isoparaffin, decahydronaphthalene (DECALIN), fatty oils, paraffin oil, silicon fluids; aromatic hydrocarbons, such as toluene, xylene, phenylxylylethane, dodecylbenzene or alkylnaphthalene; halogenated solvents; The invention can include any of a plurality of suitable solvents, such as perfluorodecalin, perfluorotoluene, perfluoroxylene, dichlorobenzotrifluoride, 3,4,5-trichlorobenzotrifluoride, chloropentafluorobenzene, dichlorononane, or pentachlorobenzene; combinations thereof; or other suitable solvents, but the present disclosure is not limited thereto.

[0059] In some embodiments, the electrophoretic medium 122 has a first refractive index. For example, the first refractive index may be greater than 1.5, such as 1.6, 1.7, 1.8, 1.9, 2.0, 2.5, 3.0, greater than 3.0, or any value or range between the above values, but the present disclosure is not limited thereto. In other embodiments, the first refractive index may be less than 1.5, such as 1.45, 1.40, 1.35, 1.30, 1.25, 1.2, 1.1, 1.0, or any value or range between the above values, but the present disclosure is not limited thereto.

[0060] In some embodiments, the electrophoretic structure 12 further includes an electrophoretic lens 123, and the electrophoretic lens 123 is disposed in the electrophoretic medium 122. Specifically, the electrophoretic lens 123 moves away from or close to the micro-LED 11 according to the electric field generated by the upper electrode 120 and the lower electrode 121, so that the light passing through it has different light-emitting angles. For example, when the electrophoretic lens 123 (for example, the electrophoretic lens 123a) is away from the micro-LED 11, the light passing through the electrophoretic lens 123 (for example, the electrophoretic lens 123a) has a first light-emitting angle θ1. On the contrary, when the electrophoretic lens 123 (for example, the electrophoretic lens 123b) is close to the micro-LED 11, the light passing through the electrophoretic lens 123 (for example, the electrophoretic lens 123b) has a second light-emitting angle θ2, and the first light-emitting angle θ1 is different from the second light-emitting angle θ2. It is worth mentioning that in order to effectively refract all or most of the light, on the projection surface, the projection area of ​​the electrophoretic lens 123 accounts for at least 50% of the projection area of ​​the light. For example, the projection area of ​​the electrophoretic lens 123 accounts for 60%, 70%, 80%, 90%, 95%, 99% of the projection area of ​​the light, or any value or range therebetween, but the disclosure is not limited thereto. In some embodiments, the diameter of the electrophoretic lens 123 is between 5 nm and 30 μm.

[0061] In some embodiments, the electrophoretic lens 123 may be or may include an organic material or an inorganic material that is completely or partially transparent. The inorganic material may be or may include glass, sapphire, rhinestone, fused silica, calcium fluoride (CaF2), titanium dioxide, silicon nitride, rutile (titania, anatase, barium sulfate, zirconium oxide, kaolin, zinc oxide), a combination thereof, or other suitable inorganic materials, but the present disclosure is not limited thereto. The organic material may be or may include polyethylene (PE), polymethylmethacrylate, polystyrene (PS), polycarbonate (PC), epoxy resin, a combination thereof, or other suitable organic materials, but the present disclosure is not limited thereto.

[0062] In some embodiments, the electrophoretic lens 123 may be or may include a material having an electric dipole moment. For example, the electrophoretic lens 123 may include an organic material or an inorganic material such as those mentioned above, and the two ends (or both sides) of the above material may have opposite charges by using a material such as a charge control agent as a charged coating. For example, the charge control agent may be ionic or non-ionic.

[0063] In some embodiments, the ionic surfactant may include an anionic surfactant or a cationic surfactant. The anionic surfactant may include: alkane carboxylic salts; alkane sulfonic salts; alkyl-aromatic sulfonic salts, such as sodium dodecylbenzenesulfonate; isopropylamine; alkyl benzene sulfonate, phosphates, phosphoricsalts; combinations thereof; or other suitable anionic surfactants, but the present disclosure is not limited thereto. The cationic surfactant may include: fatty amine salts, quaternary ammonium salts, alkyl pyridium salts, combinations thereof, or other suitable anionic surfactants, but the present disclosure is not limited thereto. In some embodiments, the nonionic surfactant may include: sorbitan monoester, polyethoxylated nonionics, polybutene succinimide, maleic anhydride copolymer, vinylpyridine copolymer, vinylpyrrolidone copolymer, (meth)acrylic acid copolymer, N,N-dimethylaminoethyl (meth)acrylate copolymer, combinations thereof or other suitable nonionic surfactants, but the present disclosure is not limited thereto.

[0064] It is worth mentioning that, although it is mentioned above that the electrophoretic lens 123 can be composed of a non-charged lens body (e.g., glass) and a charged material (e.g., charge control agent) thereon, the present disclosure is not limited thereto. In other embodiments, the electrophoretic lens 123 can also be composed of a single material that has an electric dipole moment, such as a liquid crystal molecule. In this way, the electrophoretic lens 123 can be driven by an electric field to generate an electrostatic force, thereby approaching or moving away from the micro-LED 11.

[0065] In some embodiments, the electrophoretic lens 123 has a second refractive index, and the second refractive index of the electrophoretic lens 123 is different from the first refractive index of the electrophoretic medium 122. For example, when the first refractive index of the electrophoretic medium 122 is greater than 1.5, the second refractive index of the electrophoretic lens 123 may be less than 1.5, for example, the second refractive index may be 1.45, 1.40, 1.35, 1.30, 1.25, 1.2, 1.1, 1.0, or any value or any range between the above values, but the present disclosure is not limited thereto. Conversely, when the first refractive index of the electrophoretic medium 122 is less than 1.5, the second refractive index of the electrophoretic lens 123 may be greater than 1.5, for example, the second refractive index may be 1.6, 1.7, 1.8, 1.9, 2.0, 2.5, 3.0, greater than 3.0, or any value or any range between the above values, but the present disclosure is not limited thereto. Since the two-phase interface between the electrophoretic lens 123 and the electrophoretic medium 122 has a refractive index difference, the light passing through the two-phase interface may be bent (eg, refracted).

[0066] like Figure 1 As shown, the electrophoretic lens 123a and the electrophoretic lens 123b are spherical convex lenses with a refractive index greater than that of the electrophoretic medium 122. When the distance between the electrophoretic lens 123a and the micro-LED 11a is greater than the focal length f (for example, at 1.5 times the focal length 1.5f, at two times the focal length 2f, or at three times the focal length 3f), the light passing through the electrophoretic lens 123a has a first light-emitting angle θ1. On the contrary, when the distance between the electrophoretic lens 123b and the micro-LED 11b is less than the focal length f, the light passing through the electrophoretic lens 123b has a second light-emitting angle θ2, and the second light-emitting angle θ2 is greater than the first light-emitting angle θ1. In some embodiments, the state in which the light is converged by the electrophoretic lens 123a can be referred to as a convergent model of the pixel structure 1, and the state in which the light is diverged by the electrophoretic lens 123b can be referred to as a diverging model of the pixel structure 1.

[0067] Reference Figure 2, which is a schematic diagram of a pixel structure according to other embodiments of the present disclosure. As shown in the figure, the electrophoretic lens 123c and the electrophoretic lens 123d are taken as double concave lenses with a refractive index smaller than that of the electrophoretic medium 122. In these embodiments, since the first refractive index of the electrophoretic medium 122 is greater than the second refractive index of the electrophoretic lens 123, the two interfaces between the electrophoretic medium 122 and the electrophoretic lens 123 in region A can be regarded as substantially optical single convex lenses. In this way, when the electrophoretic lens 123c is away from the micro-light emitting diode 11c, the light passing through the electrophoretic lens 123 has a first light-emitting angle θ1. Conversely, when the electrophoretic lens 123b is close to the micro-light emitting diode 11d, the light passing through the electrophoretic lens 123d has a second light-emitting angle θ2, and the second light-emitting angle θ2 is greater than the first light-emitting angle θ1. Similar to Figure 1 In the illustrated embodiment, the state in which the light is converged by the electrophoretic lens 123 c is referred to as the convergence mode of the pixel structure 1 , and the state in which the light is diverged by the electrophoretic lens 123 d is referred to as the divergence mode of the pixel structure 1 .

[0068] It is worth mentioning that in these embodiments, the second refractive index of the electrophoretic lens 123 needs to be less than the first refractive index of the electrophoretic medium 122 (to be equivalently regarded as an optical convex lens). Otherwise, when the second refractive index of the electrophoretic lens 123 is greater than the first refractive index of the electrophoretic medium 122, the interface between the electrophoretic lens 123 and the electrophoretic lens 123 is a substantial optical concave lens rather than an optical convex lens. According to the imaging principle, a concave lens cannot produce magnified imaging. As a result, this pixel structure cannot make the light angle of the refracted light greater than the light angle of the light before refraction.

[0069] Reference Figure 3 , which is a schematic diagram of a pixel structure according to some other embodiments of the present disclosure. As shown in the figure, the electrophoretic lens 123e and the electrophoretic lens 123f are cylindrical convex lenses with a refractive index greater than that of the electrophoretic medium 122. When the distance between the electrophoretic lens 123e and the micro-light emitting diode 11e is greater than the focal length f, the light passing through the electrophoretic lens 123e has a first light-emitting angle θ1. On the contrary, when the distance between the electrophoretic lens 123f and the micro-light emitting diode 11f is less than the focal length f, the light passing through the electrophoretic lens 123f has a second light-emitting angle θ2, and the second light-emitting angle θ2 is greater than the first light-emitting angle θ1. Similar to Figure 1 In the illustrated embodiment, the state in which the light is converged by the electrophoretic lens 123 e is referred to as the convergence mode of the pixel structure 1 , and the state in which the light is diverged by the electrophoretic lens 123 f is referred to as the divergence mode of the pixel structure 1 .

[0070] Compared with the aforementioned embodiments, the use of a cylindrical convex lens as the electrophoretic lens 123 may have at least the following advantageous effects, but the present disclosure is not limited thereto. Compared with a spherical convex lens, a cylindrical convex lens may be less likely to flip (or rotate) in the electrophoretic medium 122. In this way, the cylindrical convex lens may have a faster response speed (i.e., it does not need to flip to align with the direction of the electric field when driven by an electric field). Alternatively, the cylindrical convex lens may have a more precise convergence or divergence effect without deviation due to flipping.

[0071] Reference Figure 4 , which is a schematic diagram showing a pixel structure according to some other embodiments of the present disclosure. As shown in the figure, in some embodiments, the electrophoretic lens 123 may also be a cylindrical gradient refractive index lens (gradient refractive index lens). Specifically, the axis of the gradient refractive index lens is parallel to the normal direction of the upper electrode 120, and the refractive index of the gradient refractive index lens gradually decreases from the axis of the gradient refractive index lens to the outside. For example, the refractive index of the axis IL of the gradient refractive index lens may be 1.6, the refractive index of the middle layer ML may be 1.4 or 1.2, and the refractive index of the outer layer OL may be 1.1, 1.0, but the present disclosure is not limited thereto. In other embodiments, the refractive index of the gradient refractive index lens may also be reduced from 3.0 to 1.5.

[0072] When the distance between the electrophoretic lens 123g and the micro-LED 11g is greater than the focal length f, the light passing through the electrophoretic lens 123g has a first light-emitting angle θ1. Conversely, when the distance between the electrophoretic lens 123h and the micro-LED 11h is less than the focal length f, the light passing through the electrophoretic lens 123h has a second light-emitting angle θ2, and the second light-emitting angle θ2 is greater than the first light-emitting angle θ1. Figure 1 In the illustrated embodiment, the state in which the light is converged by the electrophoretic lens 123g is referred to as the convergence mode of the pixel structure 1, and the state in which the light is diverged by the electrophoretic lens 123h is referred to as the divergence mode of the pixel structure 1.

[0073] Compared with the aforementioned embodiments, the use of a cylindrical gradient refractive index lens as the electrophoretic lens 123 may have at least the following advantageous effects, but the present disclosure is not limited thereto. Compared with a convex lens or a concave lens having a concave-convex surface, the two ends of the cylindrical gradient refractive index lens are flat, which can effectively increase the distance that the electrophoretic lens 123 can move between the upper electrode 120 and the lower electrode 121. Alternatively, compared with a convex lens or a concave lens having a concave-convex surface, the use of a gradient refractive index lens with a flat surface can effectively improve the process margin and reduce the optical error. In other words, the cylindrical gradient refractive index lens can have a more precise convergence or divergence effect.

[0074] It is worth mentioning that although some types of lenses have been provided as illustrations above, the present disclosure is not limited thereto. Any lens that can produce magnified imaging or reduced imaging according to its own focal length can be applied to the present disclosure. For example, in addition to a spherical convex lens, the convex lens can also be a plano-convex lens, a bi-convex lens, and a convex-concave lens, etc., but the present disclosure is not limited thereto. In addition to a bi-concave lens, the concave lens can also be a plano-concave lens, a bi-concave lens, and a concave-convex lens, etc., but the present disclosure is not limited thereto. In addition to a cylindrical gradient refractive index lens (for example, an axial gradient refractive index lens), the gradient refractive index lens can also be a radial gradient refractive index lens and a spherical gradient refractive index lens, etc., but the present disclosure is not limited thereto.

[0075] Reference Figure 5 , which is a schematic diagram showing a pixel structure according to some other embodiments of the present disclosure. As shown in the figure, in some embodiments, the electrophoretic lens 123 includes a first sub-lens 1230 and a second sub-lens 1231. Among them, the first sub-lens 1230 is arranged between the upper electrode 120 and the second sub-lens 1231. In some embodiments, the first sub-lens 1230 and the second sub-lens 1231 may include similar or identical materials, but the present disclosure is not limited thereto. In some embodiments, the first sub-lens 1230 and the second sub-lens 1231 may have similar or identical refractive indices, but the present disclosure is not limited thereto. In some embodiments, the first sub-lens 1230 and the second sub-lens 1231 may have similar or identical sizes, but the present disclosure is not limited thereto.

[0076] In some embodiments, the first sub-lens 1230 and the second sub-lens 1231 may be lenses of the same type, for example, both are spherical convex lenses, biconcave lenses, or cylindrical gradient refractive index lenses, but the present disclosure is not limited thereto. In other embodiments, the first sub-lens 1230 and the second sub-lens 1231 may be lenses of different types, for example, they may be any two of a plano-convex lens, a biconvex lens, a convex-concave lens, a plano-concave lens, a biconcave lens, a concave-convex lens, an axial gradient refractive index lens, a radial gradient refractive index lens, a spherical gradient refractive index lens, a combination thereof, or other suitable lenses.

[0077] It is worth mentioning that in order for the upper electrode 120 and the lower electrode 121 to accurately control the first sub-lens 1230 and the second sub-lens 1231 , the electrostatic force provided by the upper electrode 120 and the lower electrode 121 must be greater than the electrostatic force between the first sub-lens 1230 and the second sub-lens 1231 .

[0078] by Figure 5Take the embodiment shown as an example. In the case where the electric dipole moments of the first sub-lens 1230 and the second sub-lens 1231 are in the same direction, the pixel structure 1 can have six different states S1-S6. Among them, states S1-S3 are states where the lower sides of the first sub-lens 1230 and the second sub-lens 1231 (i.e., the side adjacent to the lower electrode 121) are both negatively charged, and states S4-S6 are states where the lower sides of the first sub-lens 1230 and the second sub-lens 1231 (i.e., the side adjacent to the lower electrode 121) are both positively charged.

[0079] In state S1, the upper electrode 120 provides negative electricity, and the lower electrode 121 provides positive electricity, so that the first sub-lens 1230 is attracted to the upper electrode 120, and the second sub-lens 1231 is attracted to the lower electrode 121. In state S2, the upper electrode 120 provides positive electricity and the lower electrode 121 provides positive electricity, so that the first sub-lens 1230 and the second sub-lens 1231 are attracted to the lower electrode 121. In state S3, the upper electrode 120 provides negative electricity and the lower electrode 121 provides negative electricity, so that the first sub-lens 1230 and the second sub-lens 1231 are attracted to the upper electrode 120. In state S4, the upper electrode 120 provides positive electricity, and the lower electrode 121 provides negative electricity, so that the first sub-lens 1230 is attracted to the upper electrode 120, and the second sub-lens 1231 is attracted to the lower electrode 121. In state S5, both the upper electrode 120 and the lower electrode 121 provide negative electricity, so that the first sub-lens 1230 and the second sub-lens 1231 are attracted to the lower electrode 121. In state S6, both the upper electrode 120 and the lower electrode 121 provide positive electricity, so that the first sub-lens 1230 and the second sub-lens 1231 are attracted to the upper electrode 120.

[0080] Reference Figure 6 , which is a schematic diagram showing a pixel structure according to some other embodiments of the present disclosure. Figure 6 In the case where the directions of the electric dipole moments of the first sub-lens 1230 and the second sub-lens 1231 are different, the pixel structure 1 may also have six other different states S7 to S12. Among them, states S7 to S9 are states where the adjacent two sides of the first sub-lens 1230 and the second sub-lens 1231 are negatively charged, and states S10 to S12 are states where the adjacent two sides of the first sub-lens 1230 and the second sub-lens 1231 are both positively charged.

[0081] In state S7, both the upper electrode 120 and the lower electrode 121 provide negative electricity, so that the first sub-lens 1230 is attracted to the upper electrode 120, and the second sub-lens 1231 is attracted to the lower electrode 121. In state S8, the upper electrode 120 provides positive electricity, and the lower electrode 121 provides negative electricity, so that the first sub-lens 1230 and the second sub-lens 1231 are attracted to the lower electrode 121. In state S9, both the upper electrode 120 and the lower electrode 121 provide negative electricity, so that the first sub-lens 1230 and the second sub-lens 1231 are attracted to the upper electrode 120. In state S10, both the upper electrode 120 and the lower electrode 121 provide positive electricity, so that the first sub-lens 1230 is attracted to the upper electrode 120, and the second sub-lens 1231 is attracted to the lower electrode 121. In state S11, the upper electrode 120 provides negative electricity, and the lower electrode 121 provides positive electricity, so that the first sub-lens 1230 and the second sub-lens 1231 are attracted to the lower electrode 121. In state S12, the upper electrode 120 provides positive electricity, and the lower electrode 121 provides negative electricity, so that the first sub-lens 1230 and the second sub-lens 1231 are attracted to the upper electrode 120.

[0082] Through the above configuration, the first sub-lens 1230 and the second sub-lens 1231 can be effectively controlled to achieve more diverse adjustments to the light emitting angle. It is worth mentioning that although the above describes that the electrophoretic lens 123 includes two sub-lenses (for example, the first sub-lens 1230 and the second sub-lens 1231), the present disclosure is not limited thereto. In other embodiments, the electrophoretic lens 123 may also include more than two sub-lenses to achieve more complex and diverse adjustments to the light emitting angle.

[0083] Reference Figures 7 to 10 , which are respectively schematic diagrams of a convergence mode of a display pixel structure, a convergence mode of a display device, a divergence mode of a pixel structure, and a divergence mode of a display device according to some embodiments of the present disclosure. In these embodiments, the pixel structure 2 can be used as a single sub-pixel, and multiple sub-pixels (for example, a red sub-pixel, a blue sub-pixel, and a green sub-pixel) can form a pixel. Figure 7As shown, the pixel structure 2 includes a substrate 10, a first micro-light emitting diode 11X, a second micro-light emitting diode 11Y, a first electrophoretic structure 12X and a second electrophoretic structure 12Y. Compared with the pixel structure 1, the pixel structure 2 includes two light emitting diodes of the same color (for example, two red LED chips, two blue LED chips or two green LED chips) and two electrophoretic structures thereon (for example, the first electrophoretic structure 12X and the second electrophoretic structure 12Y). The first electrophoretic structure 12X and the second electrophoretic structure 12Y include upper electrodes 120X and 120Y, lower electrodes 121X and 121Y, electrophoretic media 122X and 122Y, and electrophoretic lenses 123X and 123Y, respectively.

[0084] In some embodiments, the pixel structure 2 may further include an electrochromic structure 13, and the electrochromic structure 13 is disposed between the first electrophoretic structure 12X and the second electrophoretic structure 12Y. Specifically, the electrochromic structure 13 may selectively block a portion of the first light emitted by the first micro-LED 11X and a portion of the second light emitted by the second micro-LED 11Y, so as to display different images at different viewing angles.

[0085] like Figure 7 As shown in FIG. 1 , when the electrophoretic lens 123X and the electrophoretic lens 123Y converge the light (for example, the pixel structure 2 is in the convergence mode), the first light passing through the first electrophoretic structure 12X has a first light emission angle θ1, and the second light passing through the second electrophoretic structure 12Y has a third light emission angle θ3. At this time, the electrochromic structure 13 can be made transparent (that is, the electrochromic structure 13 is in a transparent state), so that the display device DS can provide a display image facing forward, as shown in FIG. Figure 8 As shown. In some embodiments, the first micro-LED 11X and the second micro-LED 11Y can receive the same driving signal, and the electrochromic structure 13 does not shield the first light and the second light (that is, allows the first light and the second light to pass). In this way, the display device DS can provide a single display image (composed of the first light and the second light) with high brightness facing forward. It is worth mentioning that although the display device DS is described here as providing an image facing forward, users located in front of the left and right of the display device DS can still see the image.

[0086] like Fig. 9As shown, when the electrophoretic lens 123X and the electrophoretic lens 123Y diverge the light (for example, the pixel structure 2 is in the divergent mode), the first light passing through the first electrophoretic structure 12X has a second light-emitting angle θ2, and the second light passing through the second electrophoretic structure 12Y has a fourth light-emitting angle θ4. The second light-emitting angle θ2 is greater than the first light-emitting angle θ1, and the fourth light-emitting angle θ4 is greater than the third light-emitting angle θ3. At this time, the electrochromic structure 13 can be made opaque (that is, the electrochromic structure 13 is in an opaque state) (for example, black) to block part of the first light and the second light, so that the display device DS can only provide a display image toward its left front and right front, as shown in FIG. Fig.10 As shown. In some embodiments, the first micro-LED 11X and the second micro-LED 11Y can receive different driving signals respectively, and the electrochromic structure 13 can shield a portion of the first light and a portion of the second light. In this way, the display device DS can provide a first display image (consisting only of the first light) toward the left front, and the display device DS can provide a second display image (consisting only of the second light) toward the right front. Compared with the split screen of the prior art, this display device DS can display different display images on the same display panel, thereby greatly improving the applicability and user experience of the display device DS.

[0087] Reference Figure 11 to Figure 12 , which are respectively schematic diagrams of a convergence mode of a pixel structure and a divergence mode of a pixel structure according to other embodiments of the present disclosure. Figures 7 to 10 Compared with the embodiments of the present invention, the electrochromic structure 13 in these embodiments further extends between the upper electrode 120X and the electrophoretic lens 123X in the first electrophoretic structure 12X, and extends between the upper electrode 120Y and the electrophoretic lens 123Y in the second electrophoretic structure 12Y.

[0088] like Fig.11 As shown in FIG. 1 , when the electrophoretic lens 123X and the electrophoretic lens 123Y converge the light (for example, the pixel structure 2 is in the convergence mode), the first light and the second light travel toward the front of the display device DS. At this time, the electrochromic structure 13 can be made transparent (that is, the electrochromic structure 13 is in a transparent state), so that the display device DS can provide a display image toward the front thereof. Fig.12As shown, when the electrophoretic lens 123X and the electrophoretic lens 123Y diverge the light (for example, the pixel structure 2 is in the divergent mode), the first light and the second light advance toward the front, left front, and right front of the display device DS. At this time, the electrochromic structure 13 can be made opaque (that is, the electrochromic structure 13 is in an opaque state) (for example, black), so that the display device DS can only provide a display image toward the left front and right front. Since the electrochromic structure 13 in these embodiments can more significantly block the first light and the second light toward the front, it is possible to avoid the first light or the second light toward the front of the display device DS from leaving the display device DS, causing unexpected problems such as image overlap.

[0089] Several embodiments are summarized above so that those skilled in the art can better understand the concepts of the embodiments of the present disclosure. Those skilled in the art should understand that other processes and structures can be designed or modified based on the embodiments of the present disclosure to achieve the same purposes and / or advantages as the embodiments introduced herein. Those skilled in the art should also understand that such equivalent processes and structures do not deviate from the spirit and scope of the present disclosure, and can be variously changed, replaced and substituted without violating the spirit and scope of the present disclosure.

Claims

1. A pixel structure, comprising: substrate; a micro light emitting diode, disposed on the substrate, wherein the micro light emitting diode emits light; as well as An electrophoretic structure is disposed on the micro-LED, wherein the electrophoretic structure comprises: The upper electrode and the lower electrode form an electric field; an electrophoretic medium disposed between the upper electrode and the lower electrode, wherein the electrophoretic medium has a first refractive index; and an electrophoretic lens disposed in the electrophoretic medium, wherein the electrophoretic lens has a second refractive index, and the second refractive index is different from the first refractive index, The electrophoretic lens is driven by the electric field to generate electrostatic force to move away from or closer to the micro light emitting diode, so that the light passing through the electrophoretic lens has a first light emitting angle or a second light emitting angle after refraction, and the first light emitting angle is different from the second light emitting angle. 2 . The pixel structure according to claim 1 , wherein on the projection plane, the projection area of ​​the electrophoretic lens accounts for at least 50% of the projection area of ​​the micro-LED. The pixel structure according to claim 1 , wherein the first refractive index is smaller than the second refractive index. 4 . The pixel structure according to claim 3 , wherein the first refractive index is less than 1.5, and the second refractive index is greater than or equal to 1.

5.

5. The pixel structure according to claim 3, wherein the electrophoretic lens is a convex lens, and the convex lens has a focal length, When the distance between the convex lens and the micro-LED is greater than the focal length, the light passing through the convex lens has the first light-emitting angle. When the distance between the convex lens and the micro light emitting diode is less than the focal length, the light passing through the convex lens has the second light emitting angle, and the second light emitting angle is greater than the first light emitting angle.

6. The pixel structure according to claim 3, wherein the electrophoretic lens is a gradient refractive index lens, and the axis of the gradient refractive index lens is parallel to the normal direction of the upper electrode, and the refractive index of the gradient refractive index lens gradually decreases from the axis of the gradient refractive index lens to the outside, When the distance between the gradient refractive index lens and the micro-LED is greater than the focal length, the light passing through the gradient refractive index lens has the first light emission angle. When the distance between the gradient refractive index lens and the micro light emitting diode is less than the focal length, the light passing through the gradient refractive index lens has the second light emitting angle, and the second light emitting angle is greater than the first light emitting angle. The pixel structure according to claim 1 , wherein the first refractive index is greater than the second refractive index. 8 . The pixel structure according to claim 7 , wherein the first refractive index is greater than 1.5, and the second refractive index is less than or equal to 1.

5. 9 . The pixel structure according to claim 7 , wherein the electrophoretic lens is a concave lens.

10. The pixel structure according to claim 1, wherein the electrophoretic lens comprises a first sub-lens and a second sub-lens, the first sub-lens is disposed between the upper electrode and the second sub-lens, the electric dipole moments of the first sub-lens and the second sub-lens are in the same direction, and the electrostatic force provided by the upper electrode and the lower electrode is greater than the electrostatic force between the first sub-lens and the second sub-lens.

11. The pixel structure according to claim 1, wherein the electrophoretic lens comprises a first sub-lens and a second sub-lens, the first sub-lens is disposed between the upper electrode and the second sub-lens, wherein the electric dipole moments of the first sub-lens and the second sub-lens are in opposite directions, and the electrostatic force provided by the upper electrode and the lower electrode is greater than the electrostatic force between the first sub-lens and the second sub-lens.

12. A pixel structure, comprising: substrate; A first micro-LED and a second micro-LED are disposed on the substrate, and the first micro-LED and the second micro-LED respectively emit a first light and a second light of the same color; The first electrophoretic structure and the second electrophoretic structure are respectively disposed on the first micro-LED and the second micro-LED, wherein the first electrophoretic structure and the second electrophoretic structure respectively include: The upper electrode and the lower electrode form an electric field; an electrophoretic medium disposed between the upper electrode and the lower electrode, wherein the electrophoretic medium has a first refractive index; and an electrophoretic lens disposed in the electrophoretic medium, wherein the electrophoretic lens has a second refractive index, and the second refractive index is different from the first refractive index; and The electrochromic structure is disposed between the first electrophoretic structure and the second electrophoretic structure and selectively switches between a transparent state and an opaque state, wherein the opaque state is used to shield the first light and the second light in a part of the direction. The electrophoretic lens of the first electrophoretic structure is driven by the electric field to generate an electrostatic force to move away from or close to the first micro-light emitting diode, so that the first light passing through the first electrophoretic structure has a first light emitting angle or a second light emitting angle after refraction, and the first light emitting angle is different from the second light emitting angle. The electrophoretic lens of the second electrophoretic structure is driven by the electric field to generate an electrostatic force to move away from or close to the second micro-light emitting diode, so that the second light passing through the second electrophoretic structure has a third light-emitting angle or a fourth light-emitting angle after refraction, and the third light-emitting angle is different from the fourth light-emitting angle.

13. The pixel structure according to claim 12, wherein the second light emission angle is greater than the first light emission angle, and the first light passing through the first electrophoretic structure has the first light emission angle, wherein the fourth light emission angle is greater than the third light emission angle, and the second light passing through the second electrophoretic structure has the third light emission angle. 14 . The pixel structure according to claim 13 , wherein the first micro-LED and the second micro-LED receive the same driving signal, and the electrochromic structure is in a transparent state to allow the first light and the second light to pass through.

15. The pixel structure according to claim 12, wherein the second light emission angle is greater than the first light emission angle, and the first light passing through the first electrophoretic structure has the second light emission angle, wherein the fourth light emission angle is greater than the third light emission angle, and the second light passing through the second electrophoretic structure has the fourth light emission angle.

16. The pixel structure according to claim 15, wherein the first micro-LED and the second micro-LED receive different driving signals, and the electrochromic structure is in an opaque state to shield a portion of the first light and the second light. 17 . The pixel structure according to claim 12 , wherein the electrochromic structure further extends between the upper electrode and the electrophoretic lens in the first electrophoretic structure and the second electrophoretic structure.

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