WO2019127757A1

WO2019127757A1 - Display device

Info

Publication number: WO2019127757A1
Application number: PCT/CN2018/073480
Authority: WO
Inventors: 金江江; 徐湘伦
Original assignee: 武汉华星光电半导体显示技术有限公司
Priority date: 2017-12-27
Filing date: 2018-01-19
Publication date: 2019-07-04
Also published as: CN108198836A

Abstract

A display device comprises: a substrate (101); a plurality of subpixels comprising organic light-emitting diodes and arranged in an array on the substrate (101); a first inorganic layer (201) covering the plurality of subpixels; a plurality of first microstructures (300) provided at the first inorganic layer (201), the first microstructures (300) being correspondingly provided at the respective subpixels, and the first microstructures (300) being used to increase light extraction efficiency of the corresponding subpixels; a first planarization layer (401) provided over the plurality of first microstructures (300) and the first inorganic layer (201); and a second inorganic layer (202) provided over the first planarization layer (401). In the invention, microstructures are formed above subpixels to enhance light extraction efficiency and color saturation of the subpixels. Moreover, the microstructures are introduced to a package structure to ensure continuity of adhesion between respective layers, thereby increasing service life of the subpixels.

Description

Display device

Technical field

The present invention belongs to the field of display technologies, and in particular, to a display device.

Background technique

As a next-generation display technology, organic light-emitting diode (OLED) display technology has the advantages of high contrast, wide color gamut, self-luminous, fast response, and the like, especially in the flexible display technology. Nowadays, although OLED has achieved excellent results in the field of display and illumination, there are still some problems in OLED itself. For example, in flexible display, the film packaging capability still needs to be improved, so as to ensure that the OLED device has a long enough life. .

On the other hand, due to the difference in refractive index between the organic material and the electrode material, the substrate, and the air, a large amount of photons are limited to be lost in the substrate, or may be dissipated between the organic material/cathode interface by exciting the cathode surface plasma mode. Therefore, the actual light extraction efficiency of the OLED device is only 20% to 30%. The coupling of light is increased by preparing microlenses or nano-scattering layers, but practical applications are still subject to various limitations. Therefore, how to improve the light extraction efficiency of OLED devices is an urgent technical problem to be solved.

Summary of the invention

In order to solve the above problems in the prior art, it is an object of the present invention to provide a display device capable of improving the light extraction efficiency of a sub-pixel.

According to an aspect of the present invention, a display device includes: a substrate; a plurality of sub-pixels including an organic light emitting diode arrayed on the substrate; and a first inorganic layer covering the plurality of sub-pixels a plurality of first microstructures disposed on the first inorganic layer, the first microstructures being disposed on each of the sub-pixels, the first microstructures being used to increase the corresponding a light extraction efficiency of the sub-pixel; a first planar layer disposed on the plurality of first microstructures and the first inorganic layer; and a second inorganic layer disposed on the first planar layer.

Further, each of the first microstructures includes a plurality of first bumps, and the plurality of first bump arrays are distributed on the first inorganic layer.

Further, each of the first microstructures further includes a column of second bumps disposed between each adjacent two columns of first bumps, and each of the two columns of the second bumps is adjacent to the two columns first The spacing between the bumps is opposite.

Further, the cross-sectional shape of the first bump and the second bump is superior arc shape, and the superior arc shape of the superior arc is equal to or greater than 310°.

Further, the sub-pixel is one of a red sub-pixel, a green sub-pixel, and a blue sub-pixel, and the plurality of sub-pixels include a red sub-pixel, a green sub-pixel, and a blue sub-pixel; The number of bumps in the first microstructure above the green sub-pixel, the number of bumps in the first microstructure above the red sub-pixel, and the protrusion in the first microstructure above the blue sub-pixel The number of blocks increases in turn.

Further, the display device further includes: a plurality of second microstructures disposed on the second inorganic layer, the second microstructures correspondingly disposed above each of the sub-pixels, the second micro a structure for improving the light extraction efficiency of the corresponding sub-pixel; a third inorganic layer disposed on the second inorganic layer and the plurality of second microstructures; and a first impurity layer disposed on the third inorganic layer Two flat layers.

Further, each of the second microstructures includes a plurality of third bumps, and the plurality of third bump arrays are distributed on the second inorganic layer.

Further, each of the second microstructures further includes a column of fourth bumps disposed between each adjacent two columns of third bumps, each of the columns of the fourth bumps being adjacent to the two columns of the third row The spacing between the bumps is opposite.

Further, the cross-sectional shape of the third bump and the fourth bump is superior arc shape, and the superior arc shape of the superior arc is equal to or greater than 310°.

Further, the sub-pixel is one of a red sub-pixel, a green sub-pixel, and a blue sub-pixel, and the plurality of sub-pixels include a red sub-pixel, a green sub-pixel, and a blue sub-pixel; The number of bumps in the second microstructure above the green sub-pixel, the number of bumps in the second microstructure above the red sub-pixel, and the protrusion in the second microstructure above the blue sub-pixel The number of blocks increases in turn.

The invention has the beneficial effects that the invention forms a microstructure above the sub-pixel to improve the light-emitting efficiency and color saturation of the sub-pixel, and introduces the microstructure into the package structure to ensure continuous bonding between the film layers. Sex, thereby increasing the lifetime of the sub-pixels.

DRAWINGS

The above and other aspects, features and advantages of the embodiments of the present invention will become more apparent from

1A through 1E are process diagrams of a display device in accordance with an embodiment of the present invention;

Figure 2 is a plan view of Figure 1A;

3 is a top plan view of a first microstructure in accordance with an embodiment of the present invention;

4 is a cross-sectional view of a first bump in accordance with an embodiment of the present invention;

Figure 5 is a top plan view of a first microstructure in accordance with another embodiment of the present invention;

FIG. 6 is a schematic structural diagram of a display device according to still another embodiment of the present invention; FIG.

Figure 7 is a top plan view of a second microstructure in accordance with yet another embodiment of the present invention;

Figure 8 is a cross-sectional view of a third bump in accordance with an embodiment of the present invention;

9 is a top plan view of a first microstructure in accordance with yet another embodiment of the present invention.

Detailed ways

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. However, the invention may be embodied in many different forms and the invention should not be construed as being limited to the specific embodiments set forth herein. Rather, these embodiments are provided to explain the principles of the invention and the application of the invention, and the various embodiments of the invention can be understood.

In the drawings, the thickness of layers and regions are exaggerated for clarity. The same reference numerals are used throughout the drawings and the drawings.

1A through 1E are process diagrams of a display device in accordance with an embodiment of the present invention. Figure 2 is a plan view of Figure 1A.

First, referring to FIG. 1A and FIG. 2, the substrate 101 may be, for example, a TFT substrate, which may include a flexible substrate and a plurality of TFTs (thin film transistors) formed on the flexible substrate. A pixel defining layer PDL is formed on the substrate 101. The pixel defining layer PDL defines a plurality of pixel holes (not labeled) arranged in an array, and each of the pixel holes is provided with one sub-pixel, and each sub-pixel includes at least one organic light emitting Diode (OLED). As such, a plurality of sub-pixels arranged in an array are arranged on the entire substrate 101. In general, the sub-pixel may be one of a red sub-pixel, a green sub-pixel, and a blue sub-pixel, and the plurality of sub-pixels include a red sub-pixel, a green sub-pixel, and a blue sub-pixel. In FIG. 1A, only the red sub-pixel R, the green sub-pixel G, and the blue sub-pixel B will be described. In addition, it should be noted that the arrangement of each sub-pixel in FIG. 2 is only an example, and the color of the sub-pixel of the present invention and the arrangement of the sub-pixels of each color are not limited to those shown in FIG. 2 .

Next, referring to FIG. 1B, a first inorganic layer 201 is deposited on the pixel defining layer PDL, the red sub-pixel R, the green sub-pixel G, and the blue sub-pixel B. The thickness of the first inorganic layer 201 is between 100 nm and 1000 nm, and the material of the first inorganic layer 201 is a metal or non-metal nitride, a metal or non-metal oxide, a metal or a non-metal oxynitride such as SiN _x , SiO _{2 .} , SiN _x , Al ₂ O ₃ , ZrO ₂ and the like.

Next, referring to FIG. 1C, a plurality of first microstructures 300 are disposed on the first inorganic layer 201. The first microstructures 300 and the sub-pixels are in one-to-one correspondence, and the first microstructures 300 are located above the corresponding sub-pixels. That is, a first microstructure 300 is disposed on the first inorganic layer 201 above the red sub-pixel R, and a first microstructure 300 is disposed on the first inorganic layer 201 above the green sub-pixel G, above the blue sub-pixel B. A first microstructure 300 is disposed on the first inorganic layer 201. Each of the first microstructures 300 can improve the light extraction efficiency and color saturation of the corresponding sub-pixels.

3 is a top plan view of a first microstructure in accordance with an embodiment of the present invention. Referring to FIG. 3, the first microstructures 300 include a plurality of first bumps 301, and the plurality of first bumps 301 are distributed in an array on the first inorganic layer 201. 4 is a cross-sectional view of a first bump in accordance with an embodiment of the present invention. Referring to FIG. 4, the first bump 301 according to the embodiment of the present invention is entirely in the form of a large hemisphere, that is, a portion in which a complete sphere is flattened by the upper surface of the first inorganic layer 201 to a small portion, that is, The longitudinal section of the first bump 301 (cut from the upper direction to the lower side in the drawing) has a superior arc shape, that is, a large semicircular shape. Further, the arcuate radius is from 0.5 μm to 2.5 μm, but the present invention is not limited thereto. Further, the superior arc angle θ of the superior arc is equal to or greater than 310°, that is, the more complete the spherical sub-pixel of the first bump 301 is, the higher the light extraction efficiency is. The first bump 301 may be made of a material such as polyimide, epoxy, or silicone.

Figure 5 is a top plan view of a first microstructure in accordance with another embodiment of the present invention. Referring to FIG. 5, the first microstructure 300 further includes a column of second bumps 302 disposed between each adjacent two columns of first bumps 301, and each of the two columns of the second bumps 302 adjacent thereto The spacing between the columns of first bumps 301 is opposite. That is, all of the bumps of the first microstructure 300 can be arranged in a delta shape. Further, the second bump 302 is the same as the first bump 301, but the present invention is not limited thereto.

Referring back to FIG. 1C, since the light-emitting efficiency of the blue sub-pixel B, the light-emitting efficiency of the red sub-pixel R, and the light-emitting efficiency of the green sub-pixel G are sequentially lowered, in order to ensure that the light-emitting efficiency of the three is the same, the light emitted by the three is emitted. Uniform, in this embodiment, the number of bumps of the first microstructure 300 located above the blue sub-pixel B (ie, all of the first bumps 301 above the blue sub-pixel B), the number above the red sub-pixel R The number of bumps of a microstructure 300 (i.e., all of the first bumps 301 located above the red sub-pixels R) and the bumps of the first microstructures 300 above the green sub-pixels G (i.e., all located above the green sub-pixels G) The number of first bumps 301) is sequentially increased.

In addition, in another embodiment shown in FIG. 5, since the light-emitting efficiency of the blue sub-pixel B, the light-emitting efficiency of the red sub-pixel R, and the light-emitting efficiency of the green sub-pixel G are sequentially decreased, in order to ensure the light-emitting efficiency of the three. All are the same, so that the light emitted by the three is uniform, and in the other embodiment shown in FIG. 5, the bump of the first microstructure 300 located above the blue sub-pixel B (ie, all the pixels above the blue sub-pixel B) a bump 301 and the second bump 302), the bump of the first microstructure 300 located above the red sub-pixel R (ie, all the first bumps 301 and the second located above the red sub-pixel R) The number of bumps 302) and the number of bumps of the first microstructure 300 located above the green sub-pixel G (i.e., all of the first bumps 301 and the second bumps 302 above the green sub-pixel G) are sequentially increased.

Next, referring to FIG. 1D, a first planarization layer 401 is deposited on the first inorganic layer 201 and the plurality of first microstructures 300. The first flat layer 401 has a thickness of 1-20 μm, and the material of the first flat layer 401 is a material such as polyimide, epoxy or silicone, and the first flat layer 401 has a refractive index greater than that of the first inorganic layer 201 and The refractive index of the first bump 301.

Finally, referring to FIG. 1E, a second inorganic layer 202 is deposited on the first planarization layer 401. The thickness of the second inorganic layer 202 is between 100 nm and 1000 nm, and the material of the second inorganic layer 202 is a metal or non-metal nitride, a metal or non-metal oxide, a metal or a non-metal oxynitride such as SiN _x , SiO _{2 .} , SiN _x , Al ₂ O ₃ , ZrO ₂ and the like.

FIG. 6 is a schematic structural view of a display device according to still another embodiment of the present invention.

Referring to FIG. 6, the difference from the structure of the display device shown in FIG. 1E is that a plurality of second microstructures 300A are disposed on the second inorganic layer 202, and the second microstructures 300A are in one-to-one correspondence with the sub-pixels, and The second microstructure 300A is located above its corresponding sub-pixel. That is, a second microstructure 300A is disposed on the second inorganic layer 202 above the red sub-pixel R, and a second microstructure 300A is disposed on the second inorganic layer 202 above the green sub-pixel G, above the blue sub-pixel B. A second microstructure 300A is disposed on the second inorganic layer 202. Each of the second microstructures 300A can further improve the light extraction efficiency and color saturation of the corresponding sub-pixels.

Figure 7 is a top plan view of a second microstructure in accordance with yet another embodiment of the present invention. Referring to FIG. 7, the second microstructure 300A includes a plurality of third bumps 303, and the plurality of third bumps 303 are distributed in an array on the second inorganic layer 202. Figure 8 is a cross-sectional view of a third bump in accordance with an embodiment of the present invention. Referring to FIG. 8, a third bump 303 according to still another embodiment of the present invention has a large hemisphere as a whole, that is, a portion in which a complete sphere is flattened by a top surface of the second inorganic layer 202 to a small portion, that is, It is said that the longitudinal section of the third bump 303 (cut from the upper direction in the drawing) has a superior arc shape, that is, a large semicircle shape. Further, the superior arc shape has a radius of 0.5 μm to 2.5 μm, but the present invention is not limited thereto. Further, the superior arc angle θ of the superior arc is equal to or greater than 310°, that is, the more complete the spherical sub-pixel of the third bump 303 is, the higher the light-emitting efficiency is. The third bump 303 may be made of a material such as polyimide, epoxy, or silicone.

9 is a top plan view of a first microstructure in accordance with yet another embodiment of the present invention. Referring to FIG. 9, the second microstructure 300A further includes a column of fourth bumps 304 disposed between each adjacent two rows of third bumps 303, each of the adjacent ones of the columns of fourth bumps 304 The spacing between the third bumps 303 is opposite. That is to say, all the bumps of the second microstructure 300A can be arranged in a delta shape. Further, the fourth bump 304 is the same as the third bump 303, but the present invention is not limited thereto.

Referring back to FIG. 6, the number of bumps of the second microstructure 300A above the blue sub-pixel B, the number of bumps of the second microstructure 300A above the red sub-pixel R, and the second micro located above the green sub-pixel G The number of bumps of structure 300A increases in turn.

The third inorganic layer 203 is disposed on the second inorganic layer 202 and the plurality of second microstructures 300A. The thickness of the third inorganic layer 203 is between 100 nm and 1000 nm, and the material of the third inorganic layer 203 is a metal or non-metal nitride, a metal or non-metal oxide, a metal or a non-metal oxynitride such as SiN _x , SiO _{2 .} , SiN _x , Al ₂ O ₃ , ZrO ₂ and the like.

The second flat layer 402 is disposed on the third inorganic layer 203. The second flat layer 402 has a thickness of 1-20 μm, the second flat layer 402 is made of a material such as polyimide, epoxy or silicone, and the second flat layer 402 is the same as the first flat layer 401, and the first The refractive index of the second flat layer 402 is greater than the refractive indices of the third inorganic layer 203, the second inorganic layer 202, and the third bump 303.

In addition, it should be noted that the number of the bumps in the first microstructure 300 and the second microstructure 300A is not limited to those shown in the respective figures, and may be set according to actual needs.

In summary, the present invention forms a microstructure above the sub-pixel to improve the light-emitting efficiency and color saturation of the sub-pixel, and introduces the microstructure into the package structure to ensure the continuity of adhesion between the layers. , thereby increasing the lifetime of the sub-pixels.

While the invention has been shown and described with respect to the specific embodiments the embodiments of the invention Various changes in details.

Claims

A display device, comprising:

Substrate

Arraying a plurality of sub-pixels on the substrate;

a first inorganic layer covering the plurality of sub-pixels;

a plurality of first microstructures disposed on the first inorganic layer, the first microstructures being correspondingly disposed on each of the sub-pixels, wherein the first microstructure is used to increase the corresponding sub-pixels thereof Light output efficiency;

a first planar layer disposed on the plurality of first microstructures and the first inorganic layer;

a second inorganic layer disposed on the first planar layer.
The display device of claim 1, wherein each of the first microstructures comprises a plurality of first bumps, and the plurality of first bump arrays are distributed over the first inorganic layer.
The display device of claim 2, wherein each of the first microstructures further comprises a column of second bumps disposed between each adjacent two columns of first bumps, each of the columns of second bumps The spacing between the two adjacent first bumps is opposite.
The display device according to claim 3, wherein a cross-sectional shape of the first bump and the second bump is a superior arc shape, and a superior arc angle of the superior arc is equal to or greater than 310°.
The display device according to claim 2, wherein the sub-pixel is one of a red sub-pixel, a green sub-pixel, and a blue sub-pixel, and the plurality of sub-pixels include a red sub-pixel, a green sub-pixel, and Blue subpixel

The number of bumps in the first microstructure above the green sub-pixel, the number of first bumps in the first microstructure above the red sub-pixel, and the number above the blue sub-pixel The number of first bumps in a microstructure is sequentially increased.
The display device according to claim 3, wherein the sub-pixel is one of a red sub-pixel, a green sub-pixel, and a blue sub-pixel, and the plurality of sub-pixels include a red sub-pixel, a green sub-pixel, and Blue subpixel

The number of bumps in the first microstructure above the green sub-pixel, the number of first bumps and second bumps in the first microstructure above the red sub-pixel, and the number of the blue bumps The number of first bumps and second bumps in the first microstructure above the dice sub-pixels increases sequentially.
The display device according to claim 2, further comprising:

a plurality of second microstructures disposed on the second inorganic layer, the second microstructures being disposed above each of the sub-pixels, the second microstructures being used to increase the corresponding sub-pixels The light extraction efficiency of the pixel;

a third inorganic layer disposed on the second inorganic layer and the plurality of second microstructures;

a second planar layer disposed on the third inorganic layer.
The display device according to claim 3, further comprising:

a plurality of second microstructures disposed on the second inorganic layer, the second microstructures being disposed above each of the sub-pixels, the second microstructures being used to increase the corresponding sub-pixels The light extraction efficiency of the pixel;

a third inorganic layer disposed on the second inorganic layer and the plurality of second microstructures;

a second planar layer disposed on the third inorganic layer.
The display device of claim 7, wherein each of the second microstructures comprises a plurality of third bumps, and the plurality of third bump arrays are distributed over the second inorganic layer.
The display device of claim 8, wherein each of the second microstructures comprises a plurality of third bumps, and the plurality of third bump arrays are distributed over the second inorganic layer.
The display device of claim 9, wherein each of the second microstructures further comprises a column of fourth bumps disposed between each adjacent two columns of third bumps, each of the columns of fourth bumps The spacing between the two adjacent third bumps is opposite.
The display device of claim 10, wherein each of the second microstructures further comprises a column of fourth bumps disposed between each adjacent two columns of third bumps, each of the columns of fourth bumps The spacing between the two adjacent third bumps is opposite.
The display device according to claim 11, wherein a cross-sectional shape of the third bump and the fourth bump is a superior arc shape, and a superior arc angle of the superior arc is equal to or greater than 310°.
The display device according to claim 12, wherein the third bump and the fourth bump have a cross-sectional shape that is superior in arc shape, and the superior arc-shaped excellent arc angle is equal to or larger than 310°.
The display device according to claim 9, wherein the sub-pixel is one of a red sub-pixel, a green sub-pixel, and a blue sub-pixel, and the plurality of sub-pixels include a red sub-pixel, a green sub-pixel, and Blue subpixel

The number of bumps in the second microstructure above the green sub-pixel, the number of third bumps in the second microstructure above the red sub-pixel, and the location above the blue sub-pixel The number of third bumps in the second microstructure is sequentially increased.
The display device according to claim 10, wherein the sub-pixel is one of a red sub-pixel, a green sub-pixel, and a blue sub-pixel, and the plurality of sub-pixels include a red sub-pixel, a green sub-pixel, and Blue subpixel

The number of bumps in the second microstructure above the green sub-pixel, the number of third bumps in the second microstructure above the red sub-pixel, and the location above the blue sub-pixel The number of third bumps in the second microstructure is sequentially increased.
The display device according to claim 11, wherein the sub-pixel is one of a red sub-pixel, a green sub-pixel, and a blue sub-pixel, and the plurality of sub-pixels include a red sub-pixel, a green sub-pixel, and Blue subpixel

The number of bumps in the second microstructure above the green sub-pixel, the number of third bumps and fourth bumps in the second microstructure above the red sub-pixel, and the number of the blue bumps The number of third bumps and fourth bumps in the second microstructure above the dich sub-pixels increases sequentially.
The display device according to claim 12, wherein the sub-pixel is one of a red sub-pixel, a green sub-pixel, and a blue sub-pixel, and the plurality of sub-pixels include a red sub-pixel, a green sub-pixel, and Blue subpixel

The number of bumps in the second microstructure above the green sub-pixel, the number of third bumps and fourth bumps in the second microstructure above the red sub-pixel, and the number of the blue bumps The number of third bumps and fourth bumps in the second microstructure above the dich sub-pixels increases sequentially.