CN111326537A - MiniLED backlight structure and display device - Google Patents

Abstract

The application provides a MiniLED backlight structure and a display device. MiniLED backlight structure includes: an array substrate; the distributed Bragg reflector layer is arranged on the array substrate and comprises a plurality of first reflecting film layers and a plurality of second reflecting film layers which are alternately overlapped, and the refractive index of the first reflecting film layers is greater than that of the second reflecting film layers; the distributed Bragg reflector layer is provided with a plurality of mounting holes penetrating through the array substrate; the LED light-emitting units are arranged on the array substrate and positioned in the mounting holes. The light reflectivity of the LED emergent to the substrate can be improved.

Description

MiniLED backlight structure and display device

technical field

The present application relates to the field of display technology, and in particular, to a MiniLED backlight structure and a display device.

Background technique

LED, the full name of Light Emitting Diode, is considered to be a powerful representative of the next generation of display technology due to its wide color gamut, low power consumption, stability and other advantages. For display purposes, the LED size must be small to achieve high resolution. At present, MicroLED cannot be mass-produced due to problems such as difficulty in mass transfer. MiniLED came into being, using MiniLED as backlight and realizing dynamic regional dimming through array drive, also known as Local Dimmy technology, so as to achieve high contrast of LCD screen and greatly improve picture quality. The MiniLED backlight has the advantages of high brightness and low power consumption. In order to improve the light utilization rate of the LED, it is necessary to re-reflect the light emitted from the LED and the light reflected back from the Panel to the LCD. At present, the function of realizing reflection is mainly to paste the reflective film on the LED substrate. However, the cost of the reflective film is high, and it cannot be completed in the panel factory. It needs to be outsourced and the turnaround time is long.

Therefore, the prior art has defects and is in urgent need of improvement.

SUMMARY OF THE INVENTION

The purpose of the embodiments of the present application is to provide a MiniLED backlight structure and a display device. The reflective film is fabricated by the conventional chemical vapor deposition process of the panel factory, which greatly reduces the cost and product production cycle, and improves the light reflectivity from the LED to the panel. .

In a first aspect, the embodiments of the present application provide a MiniLED backlight structure, including:

an array substrate;

A distributed Bragg mirror layer, which includes a plurality of first reflective film layers and a plurality of second reflective film layers alternately stacked and formed, wherein the refractive index of the first reflective film layer is greater than the refractive index of the second reflective film layer The distributed Bragg mirror layer is provided with a plurality of mounting holes extending through the array substrate;

A plurality of LED light-emitting units, the plurality of LED light-emitting units are disposed on the array substrate and are located in the mounting holes.

Optionally, in the MiniLED backlight structure described in the embodiments of the present application, the refractive index of the first reflective film layer ranges from 1.7 to 2.2.

Optionally, in the MiniLED backlight structure described in the embodiments of the present application, the range of the refractive index of the second reflective film layer is 1.35-1.55.

Optionally, in the MiniLED backlight structure described in the embodiments of the present application, the material of the first reflective film layer is SiNx or Al2O3.

Optionally, in the MiniLED backlight structure described in the embodiments of the present application, the refractive index of the first reflective film layer is 1.96.

Optionally, in the MiniLED backlight structure described in the embodiments of the present application, the material of the second reflective film layer is SiO2 or MgF2.

Optionally, in the MiniLED backlight structure described in the embodiments of the present application, the refractive index of the second reflective film layer is 1.47.

Optionally, in the Mini LED backlight structure described in the embodiments of the present application, the number of layers of the first reflective film layer and the second reflective film layer are equal and greater than 9, and the number of layers closest to the array substrate is 9. The layer is the first reflective film layer.

Optionally, in the MiniLED backlight structure described in the embodiment of the present application, the number of layers of the first reflective film layer and the second reflective film layer is 16, and every 4 layers of the first reflective film layer and the second reflective film layer are 16 layers. The reflective film layer is respectively set with the film thickness of the center wavelength interference enhancement of red, green and blue, so as to realize the reflection of white light.

In a second aspect, an embodiment of the present application further provides a display device, including any of the Mini LED backlight structures described above.

It can be seen from the above that the embodiment of the present application adopts a distributed Bragg mirror layer, which includes a plurality of first reflective film layers and a plurality of second reflective film layers alternately stacked, and the refractive index of the first reflective film layer is greater than The refractive index of the second reflective film layer can improve the reflectance of light emitted from the LED to the substrate.

Description of drawings

In order to explain the technical solutions of the embodiments of the present application more clearly, the following briefly introduces the accompanying drawings that need to be used in the embodiments of the present application. It should be understood that the following drawings only show some embodiments of the present application, therefore It should not be regarded as a limitation of the scope. For those of ordinary skill in the art, other related drawings can also be obtained from these drawings without any creative effort.

FIG. 1 is a flowchart of a manufacturing method of a MiniLED backlight structure provided by an embodiment of the present application;

FIG. 2 is a schematic structural diagram of a MiniLED backlight structure provided by an embodiment of the present application;

FIG. 3 is another schematic structural diagram of the MiniLED backlight structure provided by the embodiment of the present application;

FIG. 4 is a graph of the reflectivity of the distributed Bragg mirror layer of the MiniLED backlight structure provided by the embodiment of the present application.

Detailed ways

The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present application.

In the description of this application, it should be noted that the orientation or positional relationship indicated by the terms "inside", "outside", etc. is based on the orientation or positional relationship shown in the accompanying drawings, or is usually placed when the product of the application is used. The orientation or positional relationship is only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the indicated device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation on the present application. Furthermore, the terms "first", "second", etc. are only used to differentiate the description and should not be construed to indicate or imply relative importance.

It should also be noted that, unless otherwise expressly specified and limited, the terms "arrangement" and "connection" should be understood in a broad sense, for example, it may be a fixed connection, a detachable connection, or an integral connection; it may be a direct connection The connection can also be indirectly connected through an intermediate medium, and it can be the internal communication of two elements. For those of ordinary skill in the art, the specific meanings of the above terms in this application can be understood in specific situations.

The following descriptions of the various embodiments refer to the accompanying drawings to illustrate specific embodiments in which the invention may be practiced. The directional terms mentioned in the present invention, such as "up", "down", "front", "rear", "left", "right", "inside", "outside", "side", etc., are only for reference Additional schema orientation. Therefore, the directional terms used are for describing and understanding the present invention, not for limiting the present invention. In the figures, structurally similar elements are denoted by the same reference numerals.

FIG. 1 is a flowchart of a manufacturing method of a Mini LED backlight structure provided by an embodiment of the present application. The fabrication of the MiniLED backlight structure includes the following steps:

S101. Provide an array substrate.

S102. Disposing a distributed Bragg mirror layer on the array substrate, which includes a plurality of first reflective film layers and a plurality of second reflective film layers alternately stacked and formed, wherein the refractive index of the first reflective film layer is greater than that of all the first reflective film layers. the refractive index of the second reflective film layer; the distributed Bragg mirror layer is provided with a plurality of mounting holes penetrating to the array substrate.

S103. Disposing a plurality of LED light-emitting units on the array substrate, the plurality of LED light-emitting units are located in the installation holes, and each of the installation holes is correspondingly installed with one of the LED light-emitting units.

Each step of the method will be described in detail below with reference to FIG. 2 .

In step S101, the array substrate 10 is similar to a conventional array substrate, and can be fabricated by the same fabrication method. The array substrate 10 includes a gate metal layer, a first insulating layer, a source/drain metal layer, a third Two insulating layers.

In this step S102, the first reflective film layer 21 and the second film layer 22 can be deposited by magnetron sputtering or chemical vapor deposition method, in this example, plasma enhanced vapor deposition method (PECVD) is used to deposit the first reflective film layer 21 alternately and the second film layer 22 .

In some embodiments, the refractive index of the first reflective film layer 21 is in the range of 1.7-2.2. The range of the refractive index of the second reflective film layer 22 is 1.35-1.55. The material of the first reflective film layer 21 is SiNx or Al2O3. Preferably, the refractive index of the first reflective film layer 21 is 1.96.

In some embodiments, the material of the second reflective film layer 22 is SiO2 or MgF2. The refractive index of the second reflective film layer 22 is 1.47.

In some embodiments, the number of layers of the first reflective film layer 21 and the second reflective film layer 22 is equal and greater than 9, and the layer closest to the array substrate 10 is the first reflective film layer 21 .

As shown in FIG. 3 , the number of layers of the first reflective film layer and the second reflective film layer are both 16, and red, green and blue are respectively provided for every 4 layers of the first reflective film layer 21 and the second reflective film layer 22 The center wavelength interference enhanced film thickness realizes the reflection of white light. Wherein, the film thickness of the first reflective film layer 21 is set to be 50-65 nm, preferably 57 nm in the first 4 periods; the film thickness of the second reflective film layer 22 is set to 70-85 nm, preferably 77 nm. In the second 4 cycles, the film thickness of the first reflective film layer 21 is set to 60-80 nm, preferably 71 nm, and the film thickness of the second reflective film layer 22 is set to 85-105 nm, preferably 94 nm. In the third 4 cycles, the film thickness of the first reflective film layer 21 is set to 75-95 nm, preferably 85 nm, and the film thickness of the second reflective film layer 22 is set to 105-120 nm, preferably 102 nm; in the fourth 4 cycles, the first reflective film is set The film thickness of the layer 21 is 90-105 nm, preferably 98 nm, and the film thickness of the second reflective film layer 22 is 120-140 nm, preferably 130 nm.

The reflectivity of the distributed Bragg reflector layer of the MiniLED backlight structure fabricated in this embodiment is shown in FIG. 4 . It can be seen from the figure that the reflectivity is relatively high in the entire visible light range, close to 90%. The LED Bonding region is exposed through a photolithography etching process, and the etching can be performed by dry etching, and then the LED light-emitting unit is transferred to the array substrate to complete the fabrication of the MiniLED backlight structure.

It can be seen from the above that the embodiment of the present application adopts a distributed Bragg mirror layer, which includes a plurality of first reflective film layers and a plurality of second reflective film layers alternately stacked, and the refractive index of the first reflective film layer is greater than The refractive index of the second reflective film layer can improve the reflectance of light emitted from the LED to the substrate.

Please continue to refer to FIG. 2 to FIG. 3 , an embodiment of the present application further provides a Mini LED backlight structure, including: an array substrate 10 , a distributed Bragg mirror layer 20 and a plurality of LED light-emitting units.

The array substrate 10 is similar to a conventional array substrate and can be fabricated by the same fabrication method. The array substrate 10 includes a gate metal layer, a first insulating layer, a source/drain metal layer, and a second insulating layer.

The first reflective film layer 21 and the second film layer 22 can be deposited by magnetron sputtering or chemical vapor deposition. In this example, plasma enhanced vapor deposition (PECVD) is used to deposit the first reflective film layer 21 and the second film layer 22 alternately. .

In some embodiments, the refractive index of the first reflective film layer 21 is in the range of 1.7-2.2. The range of the refractive index of the second reflective film layer 22 is 1.35-1.55. The material of the first reflective film layer 21 is SiNx or Al2O3. Preferably, the refractive index of the first reflective film layer 21 is 1.96.

In some embodiments, the material of the second reflective film layer 22 is SiO2 or MgF2. The refractive index of the second reflective film layer 22 is 1.47.

In some embodiments, the number of layers of the first reflective film layer 21 and the second reflective film layer 22 is equal and greater than 9, and the layer closest to the array substrate 10 is the first reflective film layer 21 .

As shown in FIG. 3 , the number of layers of the first reflective film layer and the second reflective film layer are both 16, and red, green and blue are respectively provided for every 4 layers of the first reflective film layer 21 and the second reflective film layer 22 The center wavelength interference enhanced film thickness realizes the reflection of white light. Wherein, the film thickness of the first reflective film layer 21 is set to be 50-65 nm, preferably 57 nm in the first 4 periods; the film thickness of the second reflective film layer 22 is set to 70-85 nm, preferably 77 nm. In the second 4 cycles, the film thickness of the first reflective film layer 21 is set to 60-80 nm, preferably 71 nm, and the film thickness of the second reflective film layer 22 is set to 85-105 nm, preferably 94 nm. The thickness of the first reflective film layer 21 is set to be 75-95 nm, preferably 85 nm, and the film thickness of the second reflective film layer 22 is set to 105-120 nm, preferably 102 nm in the third 4 cycles; the first reflective film is set in the fourth 4 cycles The film thickness of the layer 21 is 90-105 nm, preferably 98 nm, and the film thickness of the second reflective film layer 22 is 120-140 nm, preferably 130 nm.

The reflectivity of the distributed Bragg reflector layer of the MiniLED backlight structure fabricated in this embodiment is shown in FIG. 4 . It can be seen from the figure that the reflectivity is relatively high in the entire visible light range, close to 90%. The LED Bonding region is exposed through a photolithography etching process, and the etching can be performed by dry etching, and then the LED light-emitting unit is transferred to the array substrate to complete the fabrication of the MiniLED backlight structure.

Embodiments of the present application further provide a display device including the Mini LED backlight structure in any of the above embodiments.

It can be seen from the above that the embodiment of the present application adopts a distributed Bragg mirror layer, which includes a plurality of first reflective film layers and a plurality of second reflective film layers alternately stacked, and the refractive index of the first reflective film layer is greater than The refractive index of the second reflective film layer can improve the reflectance of light emitted from the LED to the substrate.

The above descriptions are merely examples of the present application, and are not intended to limit the protection scope of the present application. For those skilled in the art, various modifications and changes may be made to the present application. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of this application shall be included within the protection scope of this application.

Claims (10)

1. A MiniLED backlight structure, characterized in that, comprising: an array substrate; A distributed Bragg mirror layer, the distributed Bragg mirror layer is disposed on the array substrate, and the distributed Bragg mirror layer includes a plurality of first reflective film layers and a plurality of second reflective film layers alternately stacked If formed, the refractive index of the first reflective film layer is greater than the refractive index of the second reflective film layer; the distributed Bragg mirror layer is provided with a plurality of mounting holes penetrating to the array substrate; A plurality of LED light-emitting units, the plurality of LED light-emitting units are disposed on the array substrate and are located in the mounting holes. 2 . The Mini LED backlight structure according to claim 1 , wherein the refractive index of the first reflective film layer ranges from 1.7 to 2.2. 3 . 3 . The Mini LED backlight structure according to claim 1 , wherein the refractive index of the second reflective film layer ranges from 1.35 to 1.55. 4 . 4 . The Mini LED backlight structure according to claim 1 , wherein the material of the first reflective film layer is SiNx or Al2O3. 5 . 5 . The Mini LED backlight structure according to claim 4 , wherein the refractive index of the first reflective film layer is 1.96. 6 . 6 . The Mini LED backlight structure according to claim 1 , wherein the material of the second reflective film layer is SiO 2 or MgF 2 . 7 . The Mini LED backlight structure according to claim 6 , wherein the refractive index of the second reflective film layer is 1.47. 8 . 8 . The Mini LED backlight structure according to claim 1 , wherein the number of layers of the first reflective film layer and the second reflective film layer is equal to and greater than 9, and a layer closest to the array substrate is 9 . The layer is the first reflective film layer. 9 . The MiniLED backlight structure according to claim 8 , wherein the number of the first reflective film layer and the second reflective film layer is 16, and every 4 layers of the first reflective film layer and the second reflective film layer are 16. 10 . The reflective film layer is respectively set with the film thickness of the center wavelength interference enhancement of red, green and blue, so as to realize the reflection of white light. 10. A display device, comprising the MiniLED backlight structure according to any one of claims 1-9.

Images