Pixel structure

Abstract

A pixel structure comprises a substrate, a light-emitting element, a patterned light-absorbing structure and a light-condensing structure. The light-emitting element is arranged on the substrate. The patterned light-absorbing structure is disposed on the substrate, wherein the patterned light-absorbing structure includes a reflective layer facing the light-emitting element. The light-emitting element is arranged between the patterned light-absorbing structure and the light-condensing structure. The vertical projection of the light-emitting element on the substrate completely falls in the vertical projection of the light-gathering structure on the substrate, and the vertical projection of the reflecting layer on the substrate is not overlapped with the vertical projection of the light-gathering structure on the substrate.

Description

Technical Field

[0001] This invention relates to an optical structure, and more particularly to a pixel structure. Background Technology

[0002] In existing display panels, the light generated by the light-emitting elements is prone to total internal reflection within the panel, reducing light extraction efficiency. Furthermore, the display panel may produce glare due to reflections from ambient light. Summary of the Invention

[0003] This invention provides a pixel structure with good light extraction efficiency and effectively reduces the reflectivity of ambient light.

[0004] According to an embodiment of the present invention, a pixel structure is provided, including a substrate, a light-emitting element, a patterned light-absorbing structure, and a light-concentrating structure. The light-emitting element is disposed on the substrate. The patterned light-absorbing structure is disposed on the substrate, wherein the patterned light-absorbing structure includes a reflective layer facing the light-emitting element. The light-emitting element is disposed between the patterned light-absorbing structure and the light-concentrating structure. The vertical projection of the light-emitting element on the substrate falls entirely within the vertical projection of the light-concentrating structure on the substrate, and the vertical projection of the reflective layer on the substrate does not overlap with the vertical projection of the light-concentrating structure on the substrate.

[0005] Based on the above, the pixel structure provided in this embodiment of the invention utilizes a light-concentrating structure to focus light and a reflective layer with a patterned light-absorbing structure to reflect light at a large angle. Through the above design, the light extraction efficiency is improved by at least 1.5 times.

[0006] To make the above features and advantages of the present invention more apparent and understandable, specific embodiments are described below, and detailed descriptions are provided in conjunction with the accompanying drawings. Attached Figure Description

[0007] Figure 1 A planar schematic diagram of a pixel structure according to some embodiments of the present invention is shown.

[0008] Figure 2A as well as Figure 2B Cross-sectional views of a pixel structure according to a first embodiment of the present invention are shown.

[0009] Figure 3 Show Figure 2A A schematic diagram of some of the components.

[0010] Figure 4A as well as Figure 4B Cross-sectional views of a pixel structure according to a second embodiment of the present invention are shown respectively.

[0011] Explanation of reference numerals in the attached figures: 1, 2: Pixel structure 10: Substrate 20: Anti-reflective layer 100: Patterned light-absorbing structure 101: First light-absorbing section 101T: Top surface 101S: Side View 102: Second light-absorbing section 102T: Upper surface 103: Reflective layer 200: Concentrating structure BM: Black Matrix CF: Filter layer d: distance d1: Distance d2: Distance H1: Height H2: Height I1: First insulating layer I2: Second insulating layer I3: Third insulating layer LE: Light-emitting element L1: Light L2: Light T1: Thickness θ1: included angle θ2: included angle Detailed Implementation

[0012] Reference Figure 1 , Figure 2A , Figure 2B as well as Figure 3 ,in Figure 1 A planar schematic diagram of a pixel structure according to some embodiments of the present invention is shown. Figure 2A as well as Figure 2B Cross-sectional views of a pixel structure according to a first embodiment of the present invention are shown respectively. Figure 3 Show Figure 2A A schematic diagram of some of the components.

[0013] In the first embodiment of the present invention, Figure 2A It can be considered as along Figure 1 A cross-sectional view of line segment AA'. Figure 2B It can be considered as along Figure 1 A cross-sectional view of line segment BB'.

[0014] In this first embodiment, the pixel structure 1 includes a substrate 10, a plurality of light-emitting elements LE, a plurality of patterned light-absorbing structures 100, and a plurality of light-concentrating structures 200. Each light-emitting element LE is disposed on the substrate 10 and may be, for example, a light-emitting diode, but is not limited thereto. The patterned light-absorbing structures 100 are disposed on the substrate 10 and correspond to each of the light-emitting elements LE. The light-concentrating structures 200 correspond to each of the light-emitting elements LE. Each light-emitting element LE is disposed between its corresponding patterned light-absorbing structure 100 and its corresponding light-concentrating structure 200.

[0015] Each patterned light-absorbing structure 100 includes a first light-absorbing portion 101, a second light-absorbing portion 102, and a reflective layer 103. The first light-absorbing portion 101 may completely surround the corresponding light-emitting element LE, but is not limited thereto. The first light-absorbing portion 101 has a top surface 101T and a side surface 101S facing the corresponding light-emitting element LE. The reflective layer 103 is disposed on the side surface 101S of the first light-absorbing portion 101 and adjacent to the top surface 101T. The angle θ1 between the side surface 101S and the substrate 10 falls within the range of 30 degrees to 50 degrees, but is not limited thereto. The reflective layer 103 may include aluminum, silver, and titanium. The height H2 of the top surface 101T of the first light-absorbing portion 101 relative to the substrate 10 may fall within the range of 1.5 micrometers to 5.0 micrometers, but is not limited thereto.

[0016] The angle θ2 between the sidewall of the light-concentrating structure 200 and the substrate 10 can fall within the range of 50 degrees to 70 degrees. Its refractive index is greater than that of the first insulating layer I1 and the second insulating layer I2, and for example, falls within the range of 1.5 to 2.0. Its material can be a dielectric material or a resin adhesive. It should be noted that the vertical projection of the light-emitting element LE on the substrate 10 falls completely within the vertical projection of the light-concentrating structure 200 on the substrate 10, and the vertical projection of the reflective layer 103 on the substrate 10 does not overlap with the vertical projection of the light-concentrating structure 200 on the substrate 10. Accordingly, most of the light emitted by the light-emitting element LE can be focused in the positive viewing direction by the light-concentrating structure 200 (such as light L1), and the large-angle light emitted by the light-emitting element LE can be focused in the positive viewing direction after being reflected by the reflective layer 103 (such as light L2). If the vertical projection of the reflective layer 103 on the substrate 10 overlaps with the vertical projection of the light-concentrating structure 200 on the substrate 10 (i.e., the reflective layer 103 moves closer to the corresponding light-emitting element LE), it may cause large-angle light rays L2 to pass through the reflective layer 103 and not be reflected by the reflective layer 103.

[0017] Reference Figure 2A as well as Figure 3In some embodiments, in order to increase the probability that the large-angle light L2 is reflected by the reflective layer 103, the height H1 of the top surface of the light-emitting element LE relative to the substrate 10, the height H2 of the top surface 101T of the first light-absorbing part 101 relative to the substrate 10, and the distance d between the light-emitting element LE and the top surface 101T of the first light-absorbing part 101 are limited, wherein the ratio of the difference ΔH between the height H1 and the height H2 (i.e., ΔH = H1 - H2) to the distance d can fall within the range of 0.1 to 0.4.

[0018] The second light-absorbing portion 102 of the patterned light-absorbing structure 100 can be integrally formed with the first light-absorbing portion 101. The second light-absorbing portion 102 is adjacent to the side surface 101S of the first light-absorbing portion 101 and has an upper surface 102T parallel to the substrate 10. In addition, the pixel structure 1 includes an anti-reflection layer 20, wherein the light-emitting element LE, the patterned light-absorbing structure 100, and the light-concentrating structure 200 are disposed between the substrate 10 and the anti-reflection layer 20. Accordingly, the anti-reflection layer 20 can reduce the reflectivity of ambient light on the pixel structure 1, and the second light-absorbing portion 102 of the patterned light-absorbing structure 100 can reduce the reflectivity of ambient light inside the pixel structure 1. Furthermore, the top surface 101T of the first light-absorbing portion 101 does not overlap with the reflective layer 103; therefore, the top surface 101T of the first light-absorbing portion 101 can also reduce ambient light reflection.

[0019] It should also be noted that the pixel structure 1 may further include a filter layer CF, wherein the light-gathering structure 200 is disposed between the light-emitting element LE and the filter layer CF, but is not limited thereto. The thickness T1 of the light-gathering structure 200 in the Z direction may fall between 10 micrometers and 20 micrometers, but is not limited thereto. The distance d1 between the light-emitting element LE and the corresponding light-gathering structure 200 in the Z direction may, for example, fall between 0.5 micrometers and 9.0 micrometers, or between 2.0 micrometers and 3.0 micrometers. The second light-absorbing portion 102 of the patterned light-absorbing structure 100 may directly contact the conductive pad of the corresponding light-emitting element LE, or have a distance d2 between it and the conductive pad, wherein the distance d2 is less than 8.0 micrometers, but is not limited thereto.

[0020] Reference Figure 4A as well as Figure 4B , Figure 4A as well as Figure 4B Cross-sectional views of a pixel structure according to a second embodiment of the present invention are shown.

[0021] In the second embodiment of the present invention Figure 4A It can be considered as along Figure 1 A cross-sectional view of line segment AA'. Figure 4B It can be considered as along Figure 1 A cross-sectional view of line segment BB'.

[0022] The pixel structure 2 of this second embodiment differs from the pixel structure 1 of the first embodiment in that the filter layer CF is disposed between the light-emitting element LE and the light-collecting structure 200. The distance d1 between the light-emitting element LE and the corresponding light-collecting structure 200 in the Z direction can, for example, fall between 0.5 micrometers and 8.0 micrometers, or between 0.5 micrometers and 3.0 micrometers. The second light-absorbing portion 102 of the patterned light-absorbing structure 100 can directly contact the conductive pad of the corresponding light-emitting element LE, or have a distance d2 between it and the conductive pad, wherein the distance d2 is less than 8.0 micrometers, but is not limited thereto.

[0023] In summary, the pixel structure provided in this embodiment of the invention utilizes a light-concentrating structure to focus light, a reflective layer with a patterned light-absorbing structure to reflect light at large angles, and a light-absorbing portion with a patterned light-absorbing structure to reduce the reflectivity of ambient light. Through the above design, the reflectivity of ambient light can be reduced by 5%, and the light extraction efficiency is improved by at least 1.5 times.

Claims

1. A pixel structure, comprising: substrate; A light-emitting element is disposed on the substrate; A patterned light-absorbing structure is disposed on the substrate, wherein the patterned light-absorbing structure includes a reflective layer facing the light-emitting element; as well as A light-collecting structure, wherein the light-emitting element is disposed between the patterned light-absorbing structure and the light-collecting structure, wherein... The vertical projection of the light-emitting element on the substrate falls entirely within the vertical projection of the light-concentrating structure on the substrate, and the vertical projection of the reflective layer on the substrate does not overlap with the vertical projection of the light-concentrating structure on the substrate.

2. The pixel structure as claimed in claim 1, wherein the patterned light-absorbing structure further includes a first light-absorbing portion, and the reflective layer is disposed on one side of the first light-absorbing portion.

3. The pixel structure as claimed in claim 2, wherein the reflective layer is adjacent to a top surface of the first light-absorbing portion.

4. The pixel structure of claim 3, wherein a top surface of the light-emitting element has a first height relative to the substrate, the top surface of the first light-absorbing portion has a second height relative to the substrate, a distance exists between the light-emitting element and the top surface of the first light-absorbing portion, and the ratio of the difference between the first height and the second height to the distance falls within the range of 0.1 to 0.

4.

5. The pixel structure as claimed in claim 2, wherein the included angle between the side surface and the substrate is in the range of 30 degrees to 50 degrees.

6. The pixel structure of claim 2, wherein the first light-absorbing portion completely surrounds the light-emitting element.

7. The pixel structure as claimed in claim 2, wherein the patterned light-absorbing structure further includes a second light-absorbing portion, the second light-absorbing portion being integrally formed with the first light-absorbing portion and having an upper surface parallel to the substrate.

8. The pixel structure of claim 1, further comprising an anti-reflective layer, wherein the light-emitting element, the patterned light-absorbing structure, and the light-concentrating structure are disposed between the substrate and the anti-reflective layer.

9. The pixel structure of claim 1, further comprising a filter layer, wherein the light-gathering structure is disposed between the light-emitting element and the filter layer.

10. The pixel structure of claim 1, further comprising a filter layer, wherein the filter layer is disposed between the light-emitting element and the light-concentrating structure.

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