Light-emitting substrate and display device

Abstract

The present invention belongs to the technical field of display. Disclosed are a light-emitting substrate and a display device. The light-emitting substrate comprises: a dielectric substrate (10), which has a plurality of first grooves; a plurality of light-emitting chips, which are arranged on the dielectric substrate (10); and a color conversion layer, which comprises a plurality of color conversion patterns (30) located on light-emergent sides of the plurality of light-emitting chips, wherein at least one color conversion pattern (30) is located in the first groove.

Description

Light-emitting substrate and display device Technical Field

[0001] The present disclosure belongs to the field of display technology, and particularly relates to a light-emitting substrate and a display device. Background Art

[0002] Since liquid crystal itself does not emit light, various liquid crystal display devices such as liquid crystal displays and liquid crystal televisions all rely on external light sources to achieve display. Currently, liquid crystal display devices (Liquid Crystal Display, hereinafter referred to as: LCD) have gradually become the mainstream of flat panel displays. LCDs are divided into reflective LCDs and transmissive LCDs. Among them, reflective LCDs rely on external ambient light, while transmissive LCDs rely on backlight structures. Therefore, the thickness of the backlight structure directly determines the thickness of the liquid crystal display device. If an ultra-thin display device is to be realized, the thickness of the backlight structure needs to be reduced. Therefore, providing a lightweight backlight structure is a technical problem that needs to be solved urgently.

[0003] Summary of the Invention

[0004] The present invention aims to solve at least one of the technical problems existing in the prior art and provides a light-emitting substrate and a display device.

[0005] The present disclosure provides a light-emitting substrate, comprising:

[0006] a dielectric substrate having a plurality of first grooves;

[0007] A plurality of light-emitting chips are arranged on the dielectric substrate; and

[0008] The color conversion layer includes a plurality of color conversion patterns and is located on the light-emitting sides of the plurality of light-emitting chips; wherein at least one of the color conversion patterns is located in the first groove.

[0009] In some examples, the light-emitting substrate further includes a first microstructure disposed on a side of the light-emitting chip close to the color conversion pattern, and a certain distance is provided between the first microstructure and the dielectric substrate. The first microstructure is configured to gather light emitted by the light-emitting chip and transmit it to the color conversion pattern.

[0010] In some examples, the light-emitting substrate further includes a first microstructure disposed on the dielectric substrate and located on a side of the color conversion pattern close to the light-emitting chip, and a certain distance is provided between the first microstructure and the light-emitting chip, and is configured to gather light emitted by the light-emitting chip and transmit it to the color conversion pattern.

[0011] In some examples, the dielectric substrate has a plurality of second grooves, and a lens assembly of the first microstructure is disposed in one of the second grooves.

[0012] In some examples, the color conversion pattern includes a plurality of spaced-apart color conversion units; the first groove includes a plurality of spaced-apart first sub-grooves, with one color conversion unit disposed in each first sub-groove; and the lens components of the first microstructure are disposed in a one-to-one correspondence with the color conversion units.

[0013] In some examples, the color conversion layer includes multiple sub-color conversion layers and multiple transparent film layers; the sub-color conversion layers and the transparent film layers are stacked and alternately arranged; and the light emitted by the light-emitting chip is transmitted and reflected at the interface between the sub-color conversion layer and the transparent film layer.

[0014] In some examples, the light-emitting substrate further includes a semi-transmissive and semi-reflective film layer located on a side of the color conversion pattern facing away from the light-emitting chip, configured to transmit a portion of the light emitted by the light-emitting chip and reflect another portion.

[0015] In some examples, the light-emitting chip is configured to emit light of a first color, and the light of the first color excites the color conversion layer to emit light of a second color and light of a third color; the light-emitting substrate also includes a distributed Bragg reflector located on the side of the color conversion layer away from the light-emitting chip; the reflectivity of the distributed Bragg reflector to the light of the second color and the reflectivity of the light of the third color are both lower than the reflectivity to the light of the first color; and the transmittance of the distributed Bragg reflector to the light of the second color and the transmittance of the light of the third color are both higher than the transmittance to the light of the first color.

[0016] In some examples, the distributed Bragg reflector includes titanium dioxide film layers and zinc oxide film layers that are alternately arranged in a direction away from the stacking direction of the color conversion pattern; or, the distributed Bragg reflector includes zinc oxide film layers and silicon dioxide film layers that are alternately arranged in a direction away from the stacking direction of the color conversion pattern.

[0017] In some examples, the dielectric substrate has a first surface facing the light-emitting chip, the first surface has a flat area and a groove area; the first groove is located in the groove area; the flat area of ​​the first surface is a rough surface, and a first reflective layer is provided on the rough surface near the light-emitting chip.

[0018] In some examples, the dielectric substrate has a first surface facing the light-emitting chip; the light-emitting substrate also includes: a second microstructure and a light-shielding layer arranged on the first surface and arranged in sequence in a direction close to the light-emitting chip; the second microstructure is configured to diffuse the light emitted by the color conversion layer; the light-emitting substrate includes a first opening, the first opening passes through the second microstructure and the light-shielding layer, and the light emitted by the light-emitting chip can pass through the first opening to illuminate the color conversion pattern.

[0019] In some examples, an orthographic projection of one of the first grooves on the plane where the dielectric substrate is located covers an orthographic projection of one of the first openings on the plane where the dielectric substrate is located.

[0020] In some examples, the light-emitting substrate further includes a first lead end and a second lead end disposed on the dielectric substrate and disposed on two opposite sides of the first groove; the first connection pad of the light-emitting chip is connected to the first lead end, and the second connection pad of the light-emitting chip is connected to the second lead end.

[0021] In some examples, the first connection pad is disposed toward the first lead end, and the two are directly connected; the second connection pad is disposed toward the second lead end, and the two are directly connected.

[0022] In some examples, the first connection pad is disposed away from the first lead end, and the two are connected via a first signal line; the second connection pad is disposed away from the second lead end, and the two are connected via a second signal line.

[0023] In some examples, the light-emitting substrate further includes a scattering layer located on a side of the color conversion pattern facing away from the light-emitting chip.

[0024] In some examples, the light-emitting substrate further includes an encapsulation layer for covering the color conversion layer.

[0025] In some examples, the light-emitting substrate further includes a second reflective layer disposed on a side of the light-emitting chip facing away from the dielectric substrate.

[0026] In some examples, the material of the color conversion layer includes quantum dots or phosphors.

[0027] An embodiment of the present disclosure provides a display device, which includes any of the above-mentioned light-emitting substrates. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] FIG1 is a cross-sectional view of an exemplary light-emitting chip.

[0029] FIG2 is a cross-sectional view of a backlight structure according to an embodiment of the present disclosure.

[0030] FIG3 is a cross-sectional view of a first exemplary backlight structure according to an embodiment of the present disclosure.

[0031] FIG4 is a cross-sectional view of a second exemplary backlight structure according to an embodiment of the present disclosure.

[0032] FIG5 is a cross-sectional view of a backlight structure according to a third example of an embodiment of the present disclosure.

[0033] FIG. 6 is a cross-sectional view of the color conversion layer and the transparent film layer of the backlight structure shown in FIG. 5 .

[0034] FIG7 is a cross-sectional view of a fourth exemplary backlight structure according to an embodiment of the present disclosure.

[0035] FIG8 is a cross-sectional view of a fifth exemplary backlight structure according to an embodiment of the present disclosure.

[0036] FIG9 is a cross-sectional view of a distributed Rager reflector of the backlight structure shown in FIG8 .

[0037] FIG10 is a reflectivity-wavelength variation curve of the distributed Rager reflector structure shown in FIG9 .

[0038] FIG11 is a cross-sectional view of another distributed Rager reflector of the backlight structure shown in FIG8 .

[0039] FIG12 is a reflectivity-wavelength variation curve of the distributed Rager reflector structure shown in FIG11 .

[0040] FIG13 is a cross-sectional view of a sixth exemplary backlight structure according to an embodiment of the present disclosure.

[0041] FIG. 14 is a top view of the color conversion layer of the backlight structure shown in FIG. 13 .

[0042] FIG15 is a schematic diagram showing the refraction angle of light by the lens assembly and the dielectric substrate of the backlight structure shown in FIG13 .

[0043] FIG. 16 is a process flow chart of forming a first microstructure on a dielectric substrate of the backlight structure shown in FIG. 13 .

[0044] FIG17 is a cross-sectional view of a seventh exemplary backlight structure according to an embodiment of the present disclosure. DETAILED DESCRIPTION

[0045] In order to enable those skilled in the art to better understand the technical solution of the present invention, the present invention is further described in detail below with reference to the accompanying drawings and specific implementation methods.

[0046] Unless otherwise defined, the technical or scientific terms used in this disclosure should have the usual meanings understood by people with ordinary skills in the field to which this disclosure belongs. The words "first", "second" and similar words used in this disclosure do not indicate any order, quantity or importance, but are only used to distinguish different components. Similarly, words such as "one", "an" or "the" do not indicate a quantity limitation, but rather indicate the existence of at least one. Words such as "include" or "comprise" mean that the elements or objects appearing before the word include the elements or objects listed after the word and their equivalents, without excluding other elements or objects. Words such as "connect" or "connected" are not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect. "Up", "down", "left", "right" and the like are only used to indicate relative positional relationships. When the absolute position of the object being described changes, the relative positional relationship may also change accordingly.

[0047] FIG1 is a cross-sectional view of an exemplary light-emitting chip. As shown in FIG1 , the light-emitting chip may be a LED chip, which includes a transparent substrate 21 and a semiconductor stacked structure disposed on the transparent substrate 21 .

[0048] The transparent substrate 21 may be made of, but is not limited to, sapphire. Besides being an insulating substrate, the transparent substrate 21 may be a conductive substrate or a semiconductor substrate that ensures light transmission. A concave-convex structure (not shown) may be formed on the upper surface of the transparent substrate 21. This concave-convex structure can improve light extraction efficiency and enhance the quality of single crystal growth.

[0049] The semiconductor stacked structure may include a first semiconductor layer 22, an active layer 23, and a second semiconductor layer 24. The first semiconductor layer may be a layer containing In x Al y Ga 1-x-y The n-type nitride semiconductor layer may be composed of N (0≤x<1, 0≤y<1, 0≤x+y<1), and the n-type impurity may be silicon. For example, the first semiconductor layer 21 may contain n-type GaN. The second semiconductor layer 24 may contain In x Al y Ga 1-x-y N (0 ≤ x < 1, 0 ≤ y < 1, 0 ≤ x + y < 1) composition p-type nitride semiconductor layer, the p-type impurity can be magnesium. For example, the second semiconductor layer 24 can be a single layer structure, but as in some example embodiments, it can have a multi-layer structure containing different components. The active layer 23 can have a multi-quantum well (MQW) structure, in which quantum well layers and quantum barrier layers are alternately stacked with each other. For example, the quantum well layer and the quantum barrier layer can respectively include In x Al y Ga1-x-y Different components of N(0≤x≤1, 0≤y≤1, 0≤x + y≤1). In one example, the quantum well layer may include In x Ga 1-x components of N(0 < x≤1), and the quantum barrier layer may include GaN or AlGaN. The active layer 23 is not limited to the MQW structure and may have a single quantum well (SQW) structure.

[0050] In some examples, a buffer layer (not shown in the figure) may be provided between the transparent substrate 21 and the first semiconductor layer 22, and the buffer layer may have In x Al y Ga 1-x-y components of N(0≤x≤1, 0≤y≤1). For example, the buffer layer may include GaN, AlN, AlGaN, or InGaN. If necessary, the buffer layer may also be formed by combining multiple layers or gradually changing its composition.

[0051] In some examples, the LED chip includes a first electrode and a second electrode 25 that may be respectively provided on the mesa-etched region of the first semiconductor layer 22 and the second semiconductor layer 24, such that the first electrode and the second electrode 25 can be located on the same side of the LED chip. For example, the first electrode may include at least one of Al, Au, Cr, Ni, Ti, and Sn. The second electrode may include a reflective metal. For example, the second electrode 25 may include a material such as Ag, Ni, Al, Cr, Rh, Pd, Ir, Ru, Mg, Zn, Pt, or Au, and may be used as a structure with a single layer or two or more layers.

[0052] In some examples, as shown in FIG. 1, the light-emitting chip may not include a first electrode and only include a second electrode 25, and the second electrode is a transparent electrode. For example, the material of the second electrode 25 is selected from transparent conductive materials such as ITO. In this case, an insulating layer 26 is provided on the side of the second electrode 25 facing away from the second semiconductor layer 24, the first connection pad 201 is provided in the mesa-etched region of the first semiconductor layer 22 through a via hole penetrating the insulating layer 26, and the second connection pad 202 is provided on the second electrode 25 through a via hole penetrating the insulating layer 26. The first connection pad 201 and the second connection pad 202 may be located on the same side of the LED chip. Further, a current blocking layer 27 may be provided between the second electrode 25 and the second semiconductor layer 24. In the embodiments of the present disclosure, only the light-emitting chip with this structure is taken as an example for illustration.

[0053] In the embodiments of the present disclosure, a light-emitting substrate using the aforementioned LED chip is provided. The light-emitting substrate includes, but is not limited to, a backlight structure. In the embodiments of the present disclosure, the light-emitting substrate is described as a backlight structure. The LED chip can be a blue LED chip. Of course, the LED chip can also be a green LED chip, a red LED chip, or a variety of colors among these. However, in the embodiments of the present disclosure, a blue LED chip is used as an example.

[0054] It should also be noted that in the embodiment of the present disclosure, when the LED chip adopts a blue light LED chip, the color conversion layer can be composed of a red light color conversion material and a green light color conversion material. For example, the material of the color conversion layer is selected from quantum dots or phosphors. When the material of the color conversion layer is selected from quantum dots, the material of the color conversion layer can specifically include red quantum dots and green quantum dots. In this case, the blue light emitted by the blue light LED chip can excite the red quantum dots to emit red light, and excite the green quantum dots to emit green light. When the material of the color conversion layer is selected from phosphors, the material of the color conversion layer can specifically include red phosphors and green phosphors. In this case, the blue light emitted by the blue light LED chip can excite the red phosphor to emit red light, and excite the green phosphor to emit green light. That is to say, the first color mentioned in the embodiment of the present disclosure is blue, the second color is green, and the third color is red.

[0055] Next, the backlight structure provided by the embodiment of the present disclosure is described in detail.

[0056] Figure 2 is a cross-sectional view of a backlight structure according to an embodiment of the present disclosure. As shown in Figure 2 , the present disclosure provides a backlight structure comprising a dielectric substrate 10, multiple LED chips 20, and a color conversion layer located on the light-emitting surface of the LED chips 20. The dielectric substrate 10 according to the present disclosure has multiple first grooves, and the color conversion layer includes multiple color conversion patterns 30. At least one color conversion pattern 30 is located within a first groove.

[0057] It should be noted that, in the embodiment of the present disclosure, the color conversion patterns 30 and the first grooves are arranged in a one-to-one correspondence as an example, and one color conversion pattern 30 is arranged in one first groove, corresponding to one LED chip.

[0058] In the backlight structure of the embodiment of the present disclosure, by providing a first groove on the dielectric substrate 10 and placing the color conversion pattern 30 in the first groove, the thickness of the backlight structure can be effectively reduced, thereby achieving a lightweight and thin backlight structure.

[0059] In some examples, the dielectric substrate 10 includes but is not limited to a glass substrate. In the embodiment of the present disclosure, only the glass substrate is used as an example for explanation.

[0060] In some examples, referring again to FIG. 2 , the backlight structure of the disclosed embodiments not only includes the aforementioned structure but may also include a scattering layer 40 disposed on the side of the color conversion pattern 30 facing away from the LED chip 20. This scattering layer 40 may be disposed within the first groove, between the bottom of the first groove and the color conversion pattern 30. This scattering layer 40 is configured to scatter the light emitted by the LED chip 20 through the color conversion pattern 30. It should be noted that the light emitted through the color conversion pattern 30 includes not only light emitted by the LED chip 20 activating the color conversion material of the color conversion pattern 30, but also a portion of the light emitted by the LED chip 20. In other words, the light emitted through the color conversion pattern 30 includes red, green, and blue light.

[0061] Continuing with FIG. 2 , the dielectric substrate 10 has a first surface facing the LED chip 20. The backlight structure includes not only the aforementioned structure but also a second microstructure 50 and a light shielding layer 60 disposed on the first surface and arranged sequentially in a direction proximate to the LED chip 20. The second microstructure 50 is configured to diffuse light emitted from the color conversion layer. The backlight structure includes a first opening that extends through the second microstructure 50 and the light shielding layer 60. Light emitted from the LED chip 20 can pass through the first opening and illuminate the color conversion pattern 30. The first opening can be provided in a one-to-one correspondence with each LED chip 20. In this case, light scattered by the scattering layer 40 illuminates the second microstructure 50 and is further diffused, making the light more uniform. Furthermore, the light shielding layer 60 effectively prevents light leakage.

[0062] Furthermore, the second microstructure 50 may be a lens structure, which is equivalent to a diffusion plate. The light shielding layer 60 may be made of a black resin material or a light shielding metal material, which is not specifically limited in the embodiment of the present disclosure.

[0063] Furthermore, the orthographic projection of a first groove on the plane of the dielectric substrate 10 covers the orthographic projection of a first opening on the plane of the dielectric substrate 10. That is, the size of the first opening is smaller than the maximum diameter of the first groove, that is, the edge of the first groove opening is covered by the second microstructure 50 and the light shielding layer 60, thereby effectively preventing light leakage.

[0064] Continuing with FIG. 2 , an encapsulation layer 70 is disposed on the side of the light-shielding layer 60 facing away from the dielectric substrate 10. This encapsulation layer 70 covers at least the color conversion layer to prevent corrosion of the color conversion layer by external water and oxygen. Specifically, the encapsulation layer 70 can be formed on the side of the light-shielding layer 60 facing away from the second microstructure 50 and have a planar structure, thereby better sealing the structure on the dielectric substrate 10.

[0065] 2 , the side of the LED chip 20 facing away from the dielectric substrate 10 is covered with a second reflective layer 100 to allow light emitted by the LED chip 20 to be emitted toward the dielectric substrate 10. In some examples, the second reflective layer 100 includes but is not limited to white oil.

[0066] In some examples, referring again to FIG. 2 , the LED chip 20 is flip-chip mounted, meaning that the first connection pad 201 and the second connection pad 202 of the LED chip 20 are disposed toward the dielectric substrate 10. Accordingly, the backlight structure includes a first lead terminal 81 and a second lead terminal 82 disposed on the dielectric substrate 10 and disposed on opposite sides of the first groove. The first connection pad 201 of the LED chip 20 is connected to the first lead terminal 81, and the second connection pad 202 of the LED chip 20 is connected to the second lead terminal 82. Specifically, the first connection pad 201 and the first lead terminal 81 can be connected by welding, and similarly, the second connection pad 202 and the second lead terminal 82 can also be connected by welding.

[0067] Of course, the LED chip 20 is also mounted in a vertical arrangement, that is, the first connection pad 201 and the second connection pad 202 of the LED chip 20 are arranged away from the dielectric substrate 10. Accordingly, the first connection pad 201 and the first lead terminal 81 provided on the dielectric substrate 10 can be connected via a first signal line 101, and the second connection pad 202 and the second lead terminal 82 provided on the dielectric substrate 10 can be connected via a second signal line 102. In this example, the vertical arrangement of the LED chip 20 can further reduce the distance between the light emitting surface of the LED chip 20 and the color conversion pattern 30, thereby shortening the transmission distance of light emitted by the LED chip 20 in the air medium and improving light utilization efficiency.

[0068] The backlight structure of the embodiment of the present disclosure is described below with reference to specific examples.

[0069] Example 1: Figure 3 is a cross-sectional view of a backlight structure according to a first example of an embodiment of the present disclosure. As shown in Figure 3, the backlight structure comprises a dielectric substrate 10, an LED chip 20, a color conversion layer, and a first microstructure 90. The first microstructure 90 is located between the LED chip 20 and the color conversion layer. The dielectric substrate 10 has multiple first grooves, each containing a color conversion pattern 30. The first microstructure 90 is positioned above the light-emitting area Q1 of the LED chip 20 and spaced a certain distance from the dielectric substrate 10. The first microstructure 90 is capable of focusing light emitted by the LED chip 20 and transmitting it to the color conversion pattern 30.

[0070] Specifically, in the backlight structure of the present embodiment, a first microstructure 90 is provided on the light-emitting surface of the LED chip 20 to focus the light emitted by the LED chip 20. This prevents the light from being scattered. The light focused by the first microstructure 90 is then collimated and irradiated onto the color conversion pattern 30. In this case, the provision of the first microstructure 90 on the light-emitting surface of the LED chip 20 reduces the distance that the light emitted by the LED chip 20 must travel through air, effectively alleviating light loss caused by the large distance between the LED chip 20 and the color conversion pattern 30, thereby improving light utilization. Furthermore, after passing through the first microstructure 90, the light emitted by the LED chip 20 is collimated and irradiated onto the color conversion pattern 30, reducing the amount of reflected light entering the color conversion pattern 30.

[0071] In some examples, the first microstructure 90 may be a lens array composed of a plurality of lens components 901 arranged in an array.

[0072] In some examples, referring again to FIG3 , the backlight structure of the disclosed embodiments not only includes the aforementioned structure but also includes a scattering layer 40 disposed on the side of the color conversion pattern 30 facing away from the LED chip 20. The scattering layer 40 can be disposed within the first groove, between the bottom of the first groove and the color conversion pattern 30. The scattering layer 40 is configured to scatter light redirected by the color conversion pattern 30. Furthermore, referring again to FIG3 , the dielectric substrate 10 has a first surface facing the LED chip 20. The backlight structure includes not only the aforementioned structure but also includes: a second microstructure 50 and a light shielding layer 60 disposed on the first surface, arranged sequentially in a direction toward the LED chip 20. The second microstructure 50 is configured to diffuse light emitted from the color conversion layer. The backlight structure includes a first opening that extends through the second microstructure 50 and the light shielding layer 60, allowing light emitted from the LED chip 20 to pass through the first opening and illuminate the color conversion pattern 30. In this case, the light scattered by the scattering layer 40 is irradiated to the second microstructure 50 and is further diffused, so that the light is more uniform. At the same time, by providing the light shielding layer 60, light leakage can be effectively prevented.

[0073] Furthermore, the second microstructure 50 may be a lens structure, which is equivalent to a diffusion plate. The light shielding layer 60 may be made of a black resin material or a light shielding metal material, which is not specifically limited in the embodiment of the present disclosure.

[0074] Furthermore, the orthographic projection of a first groove on the plane of the dielectric substrate 10 covers the orthographic projection of a first opening on the plane of the dielectric substrate 10. That is, the size of the first opening is smaller than the maximum diameter of the first groove. That is, the edge of the first groove opening is covered by the second microstructure 50 and the light shielding layer 60, thereby effectively preventing light leakage.

[0075] Continuing with FIG. 3 , an encapsulation layer 70 is disposed on the side of the light-shielding layer 60 facing away from the dielectric substrate 10. This encapsulation layer 70 covers at least the color conversion layer to prevent corrosion of the color conversion layer by external water and oxygen. Specifically, the encapsulation layer 70 can be formed on the side of the light-shielding layer 60 facing away from the second microstructure 50 and have a planar structure, thereby better sealing the structures on the dielectric substrate 10.

[0076] 3 , the side of the LED chip 20 facing away from the dielectric substrate 10 is covered with a second reflective layer 100 to allow light emitted by the LED chip 20 to be emitted toward the dielectric substrate 10. In some examples, the second reflective layer 100 includes but is not limited to white oil.

[0077] In some examples, referring again to FIG. 3 , the LED chip 20 is flip-chip mounted, meaning that the first connection pad 201 and the second connection pad 202 of the LED chip 20 are disposed toward the dielectric substrate 10. Accordingly, the backlight structure includes a first lead terminal 81 and a second lead terminal 82 disposed on the dielectric substrate 10 and arranged on opposite sides of the first groove. The first connection pad 201 of the LED chip 20 is connected to the first lead terminal 81, and the second connection pad 202 of the LED chip 20 is connected to the second lead terminal 82. Specifically, the first connection pad 201 and the first lead terminal 81 can be connected by welding, and similarly, the second connection pad 202 and the second lead terminal 82 can also be connected by welding.

[0078] Second Example: FIG4 is a cross-sectional view of a backlight structure according to a second example of an embodiment of the present disclosure. As shown in FIG4 , this backlight structure is substantially the same as that of the first example, differing only in that the LED chip 20 in this example is disposed in a front-mounted configuration, i.e., the first connection pad 201 and the second connection pad 202 of the LED chip 20 are disposed away from the dielectric substrate 10. Accordingly, the first connection pad 201 can be connected to the first lead terminal 81 disposed on the dielectric substrate 10 via a first signal line 101, and the second connection pad 202 can be connected to the second lead terminal 82 disposed on the dielectric substrate 10 via a second signal line 102. In this example, the front-mounted configuration of the LED chip 20 further reduces the distance between the light-emitting surface of the LED chip 20 and the color conversion pattern 30, thereby shortening the transmission distance of light emitted by the LED chip 20 in the air medium and improving light utilization.

[0079] In some examples, the two ends of the first signal line 101 can be connected to the first connection pad 201 and the first lead terminal 81, respectively, by welding. Similarly, the two ends of the second signal line 102 can be connected to the second connection pad 202 and the second lead terminal 82, respectively, by welding. Of course, the first signal line 101 and the second signal line 102 can also be formed by depositing metal. In this case, the two ends of the first signal line 101 are directly connected to the first connection pad 201 and the first lead terminal 81, respectively, and the two ends of the second signal line 102 are directly connected to the second connection pad 202 and the second lead terminal 82, respectively.

[0080] The remaining structures in this example can adopt the same structures as those in the first example, so they will not be repeated here.

[0081] Third Example: FIG5 is a cross-sectional view of a backlight structure according to a third example of the presently disclosed embodiment; FIG6 is a cross-sectional view of the color conversion pattern and transparent film layer of the backlight structure shown in FIG5 . As shown in FIG5 and FIG6 , this backlight structure is substantially the same as that of the first example, differing only in that the color conversion pattern 30 in this example comprises multiple sub-color conversion layers 301 and transparent film layers 110. The sub-color conversion layers 301 and transparent film layers 110 are stacked and alternately arranged. In this case, light emitted by the LED chip 20 is transmitted and reflected at the interface between the sub-color conversion layers 301 and the transparent film layers 110. In other words, light emitted by the LED chip 20 is transmitted and reflected at the upper and lower interfaces of the transparent film layers 110.

[0082] Specifically, taking an LED chip 20 emitting blue light (i.e., a blue LED chip 20) and a color conversion pattern 30 comprising red and green color conversion materials as an example, in conventional backlight structures, the blue light output rate is greater than the red / green light output rate due to the low conversion efficiency of the color conversion pattern 30. Referring to FIG6 , in this example, by alternating sub-color conversion layers 301 and transparent film layers 110, the blue light emitted by the LED chip 20 partially transmits through the upper and lower interfaces of the transparent film layer 110, which in turn excites the sub-color conversion layers 301 and converts it into red and green light. The reflected light further transmits and reflects between the film layers, exciting the sub-color conversion layers 301 and converting it into red and green light, thereby improving color conversion efficiency and alleviating the bluish backlight output problem.

[0083] In some examples, a transparent film layer 110 is disposed between any two adjacent sub-color conversion layers 301 of the color conversion pattern 30. Light emitted by the LED chip 20 is transmitted and reflected at the upper and lower interfaces of the transparent film layer 110, thereby increasing the optical path length of the light emitted by the LED chip 20 and improving color conversion efficiency.

[0084] The remaining structures in this example can adopt the same structures as those in the first example, so they will not be repeated here.

[0085] Fourth example: FIG7 is a cross-sectional view of the backlight structure of the fourth example of the embodiment of the present disclosure; as shown in FIG7 , the backlight structure is substantially the same as the structure in the first example, with the only difference being that a semi-transparent and semi-reflective film layer is provided on the side of the color conversion pattern 30 of the backlight structure away from the light-emitting chip, and the semi-reflective and semi-transparent film layer 120 is configured to transmit a portion of the light emitted by the LED chip 20 and reflect the other portion.

[0086] For example, consider an LED chip 20 emitting blue light (i.e., a blue LED chip 20) and a color conversion pattern 30 comprising red and green color conversion materials. In conventional backlight structures, due to the low conversion efficiency of the color conversion pattern 30, the blue light output rate is higher than the red and green light output rates. In this example, a semi-reflective and semi-transmissive film layer 120 is provided to transmit a portion of the light emitted by the LED chip 20 while reflecting the remainder. The reflected light further stimulates the color conversion pattern 30 to convert it into red and green light, improving the color conversion efficiency of the color conversion pattern 30 and thereby alleviating the bluish backlight output issue.

[0087] In some examples, when a scattering layer 40 is provided in the backlight structure, the transflective film layer 120 can be provided between the color conversion pattern 30 and the scattering layer 40. In this case, the light can be fully converted and then scattered by the scattering layer 40 before being emitted.

[0088] The remaining structures in this example can adopt the same structures as those in the first example, so they will not be repeated here.

[0089] Fifth Example: Figure 8 is a cross-sectional view of a backlight structure according to a fifth example of the presently disclosed embodiment. As shown in Figure 8 , this backlight structure is substantially identical to the structure of the first example, differing only in that it further includes a distributed Bragg reflector (DBR) 140 located on the side of the color conversion pattern 30 facing away from the light-emitting chip. For example, assuming that the LED chip 20 emits blue light and the color conversion pattern 30 includes red and green color conversion materials, the DBR 140 has a lower reflectivity for red and green light than for blue light, and a higher transmittance for red and green light than for blue light. In other words, the DBR 140 has a high reflectivity for blue light and a high transmittance for red and green light. In this example, the distributed Rager reflector 140 highly reflects the blue light, so that the reflected blue light can further stimulate the color conversion pattern 30 to convert it into red and green light, thereby improving the color conversion efficiency of the color conversion pattern 30 and alleviating the problem of the backlight output being blue.

[0090] The distributed Rager reflector 140 is composed of alternating first and second film layers, each having different refractive indices. For example, the refractive index of the first film layer is greater than that of the second film layer. The refractive indices of the first and second film layers determine the reflectivity of the distributed Rager reflector 140. Specifically, the reflectivity of the distributed Rager reflector 140 is calculated using the following formula:

[0091] Wherein, N represents the number of pairs of dielectric layers (each adjacent first film layer and second film layer constitutes a pair of dielectric layers), n H is the refractive index of the first film layer, n L is the refractive index of the second film layer, n o is the refractive index of the incident medium, n i is the refraction of the output medium; the bandwidth of the photon bandgap Δλ is given by the following formula:

[0092] Where λ0 is the center wavelength of the band.

[0093] Accordingly, two exemplary distributed Lager reflectors 140 are provided in the embodiment of the present disclosure, and the number of logarithms of the dielectric layers is 5. One distributed Lager reflector 140 is composed of alternating titanium dioxide TiO2 and zinc oxide ZnO, and the other distributed Lager reflector 140 is composed of alternating zinc oxide ZnO and silicon dioxide SiO2.

[0094] In one example, Figure 9 shows a cross-sectional view of a distributed Rager reflector 140 in the backlight structure shown in Figure 8 . As shown in Figure 9 , when the distributed Rager reflector 140 is composed of alternating TiO2 and ZnO layers, the thickness of each TiO2 layer is 44 nm, the thickness of each ZnO layer is 56 nm, and λ0 is 450 nm. Using the above-mentioned formula for calculating the bandwidth Δλ of the photonic bandgap, the bandwidth Δλ is approximately 70 nm. The reflectivity-wavelength curve for this distributed Rager reflector 140 is shown in Figure 10 . Given the central wavelength of blue light at 450 nm, the central wavelength of green light at 535 nm, and the central wavelength of red light at 640 nm, the reflectivity corresponding to the central wavelength of blue light is 98%, the reflectivity corresponding to the central wavelength of green light is 10%, and the reflectivity corresponding to the central wavelength of red light is 10%. This indicates that this distributed Rager reflector 140 achieves high reflectivity for blue light and high transmittance for red and green light.

[0095] In another example, Figure 11 shows a cross-sectional view of another distributed Ragu reflector 140 in the backlight structure shown in Figure 8 . As shown in Figure 11 , when the distributed Ragu reflector 140 is composed of alternating ZnO and SiO2 layers, each ZnO layer has a thickness of 75 nm, each SiO2 layer has a thickness of 56 nm, and λ0 is 450 nm. Using the above-mentioned formula for calculating the bandwidth Δλ of the photonic bandgap, the bandwidth Δλ is approximately 90 nm. The reflectivity-wavelength curve for this distributed Ragu reflector 140 is shown in Figure 12 . Given the central wavelength of blue light at 450 nm, the central wavelength of green light at 535 nm, and the central wavelength of red light at 640 nm, the reflectivity corresponding to the central wavelength of blue light is 95%, the reflectivity corresponding to the central wavelength of green light is 5%, and the reflectivity corresponding to the central wavelength of red light is 5%. This indicates that the distributed Ragu reflector 140 with this structure can achieve high reflectivity for blue light and high transmittance for red and green light.

[0096] Only two specific structures of the distributed Lager reflector 140 are given above. It should be understood that the structure of the distributed Lager reflector 140 is not limited to the above structures, and the structure of the distributed Lager reflector 140 can be specifically designed according to specific reflectivity requirements.

[0097] In some examples, the distributed Rager reflector 140 can be specifically disposed on the side of the dielectric substrate 10 facing away from the LED chip 20. This location facilitates product manufacturing. Of course, the distributed Rager reflector 140 can be located on the light-emitting side where the color conversion layer is disposed.

[0098] The remaining structures in this example can adopt the same structures as those in the first example, so they will not be repeated here.

[0099] Sixth Example: Figure 13 is a cross-sectional view of a backlight structure according to the sixth example of the embodiment of the present disclosure; Figure 14 is a top view of the color conversion layer of the backlight structure shown in Figure 13. As shown in Figures 13 and 14, the backlight structure includes a dielectric substrate 10, multiple LED chips 20, a color conversion layer, and multiple first microstructures 90. The color conversion layer includes multiple color conversion patterns 30, with the first microstructures 90 located between the LED chips 20 and the color conversion patterns 30. For example, the color conversion patterns 30 are made of quantum dot material. The color conversion pattern 30 includes multiple color conversion units 310 spaced apart, for example, arranged in an array. The dielectric substrate 10 has multiple first grooves and multiple second grooves corresponding to the LED chips 20. Each first groove includes multiple first sub-grooves, each of which contains a color conversion unit 310. A lens assembly 901 for the first microstructure 90 is located within each second groove. Light emitted by the LED chips 20 is focused by the lens assembly 901 and then irradiated onto the corresponding color conversion unit 310. In this example, by providing the lens assembly 901, the color conversion material can be printed directly below the lens assembly 901, that is, the color conversion unit 310 is formed, the color conversion unit 310 is arranged in an array, and the problem of large light output area is solved.

[0100] Specifically, the dielectric substrate 10 has a first surface and a second surface disposed opposite each other along its thickness, with the first surface being closer to the LED chip 20 than the second surface. A first groove is formed on the second surface, and a second groove is formed on the first surface. A color conversion unit 310 is disposed within a first sub-groove of the first groove, and a lens assembly 901 is disposed within a second groove. The lens assembly 901 corresponds to the color conversion unit 310 and is spaced a certain distance from the LED chip. Light emitted by the LED chip 20 is focused by the lens assembly 901 and irradiated onto the color conversion unit 310. In this case, the refractive index coefficient of the lens component 901 should be greater than the refractive index coefficient of the dielectric substrate 10. Figure 15 is a schematic diagram of the refraction angle of light by the lens component 901 and the dielectric substrate 10 of the backlight structure shown in Figure 13. As shown in Figure 15, the incident angle of the light emitted by the LED chip 20 to the lens component 901 is θ1, and the output angle emitted by the lens component 901 is θ2, θ2>θ1, thereby achieving the convergence of light.

[0101] In some examples, FIG16 is a process flow chart for forming the first microstructure 90 on the dielectric substrate 10 of the backlight structure shown in FIG13 . As shown in FIG16 , taking a glass substrate as an example, the following process steps may be used to form the first microstructure 90 on the glass substrate:

[0102] S11, coating a nanoimprint adhesive 200 on a glass substrate.

[0103] S12 , processing the nanoimprint adhesive 200 by nanoimprint technology to obtain a first pattern 210 that matches the second groove to be formed.

[0104] S13, etching the glass substrate to form a pattern 10a including a second groove.

[0105] S14 , filling the second groove 10 a with a lens material to form a lens component 901 located in the second groove, thereby forming a first microstructure 90 (the first microstructure 90 includes the lens component 901 ).

[0106] In some examples, the backlight structure includes not only the aforementioned structure but also a distributed Bragg reflector 140 located on the side of the color conversion pattern 30 facing away from the LED chip 20. Distributed Bragg reflector 140 can employ the same structure as in the fifth example and will not be described further here. Distributed Bragg reflector 140 highly reflects blue light, allowing the reflected blue light to further stimulate the color conversion pattern 30 to convert it into red and green light, improving the color conversion efficiency of the color conversion pattern 30 and thereby alleviating the bluish cast of the backlight output.

[0107] Furthermore, an encapsulation layer 70 is provided on one side of the dielectric substrate 10 of the distributed Bragg reflector 140. The encapsulation layer 70 covers at least the color conversion layer to prevent water and oxygen corrosion. Specifically, the encapsulation layer 70 can be a planar structure, which can better seal the structure on the dielectric substrate 10.

[0108] In some examples, the backlight structure of the embodiments of the present disclosure not only includes the aforementioned structure, but may also include a scattering layer 40 disposed on a side of the color conversion pattern 30 facing away from the LED chip 20. The scattering layer 40 may be disposed between the distributed Bragg reflector 140 and the color conversion pattern 30 to scatter the light emitted by the LED chip 20, the light converted by the color conversion pattern 30, and the light transmitted through the color conversion pattern 30.

[0109] Continuing with FIG. 13 , the dielectric substrate 10 has a first surface facing the LED chip 20. The backlight structure includes not only the aforementioned structure but also a second microstructure 50 and a light shielding layer 60 disposed on the first surface and arranged sequentially in a direction proximate to the LED chip 20. The second microstructure 50 is configured to diffuse light emitted from the color conversion layer. The backlight structure includes a first opening that extends through the second microstructure 50 and the light shielding layer 60. Light emitted from the LED chip 20 can pass through the first opening and illuminate the color conversion pattern 30. For example, if the first openings are provided in a one-to-one correspondence with each LED chip 20, light scattered by the scattering layer 40 is further diffused by the second microstructure 50, resulting in a more uniform light distribution. Furthermore, the light shielding layer 60 effectively prevents light leakage.

[0110] Furthermore, the second microstructure 50 may be a lens structure, which is equivalent to a diffusion plate. The light shielding layer 60 may be made of a black resin material or a light shielding metal material, which is not specifically limited in the embodiment of the present disclosure.

[0111] In some examples, referring again to FIG. 13 , the LED chip 20 is flip-chip mounted, with the first and second connection pads 201, 202 of the LED chip 20 facing the dielectric substrate 10. Accordingly, the backlight structure further includes a first lead terminal 81 and a second lead terminal 82 disposed on the dielectric substrate 10 and arranged on opposite sides of the first recess. The first connection pad 201 of the LED chip 20 is connected to the first lead terminal 81, and the second connection pad 202 of the LED chip 20 is connected to the second lead terminal 82. Specifically, the first connection pad 201 and the first lead terminal 81 can be connected by welding, and similarly, the second connection pad 202 and the second lead terminal 82 can also be connected by welding.

[0112] Of course, the LED chip 20 is also mounted in a vertical arrangement, that is, the first connection pad 201 and the second connection pad 202 of the LED chip 20 are positioned away from the dielectric substrate 10. Accordingly, the first connection pad 201 can be connected to the first lead terminal 81 provided on the dielectric substrate 10 via a first signal line 101, and the second connection pad 202 can be connected to the second lead terminal 82 provided on the dielectric substrate 10 via a second signal line 102. Mounting the LED chip 20 in a vertical arrangement can further reduce the distance between the light emitting surface of the LED chip 20 and the color conversion pattern 30, thereby reducing the transmission distance of light emitted by the LED chip 20 in the air medium and improving light utilization efficiency. The connection method of the LED chip 20 can be similar to the connection method of the second example, and therefore will not be repeated here.

[0113] 13 , the side of the LED chip 20 facing away from the dielectric substrate 10 is covered with a second reflective layer 100 to allow light emitted by the LED chip 20 to be emitted toward the dielectric substrate 10. In some examples, the second reflective layer 100 includes but is not limited to white oil.

[0114] Seventh Example: Figure 17 is a cross-sectional view of a backlight structure according to the seventh example of the disclosed embodiment. As shown in Figure 17, this backlight structure is substantially identical to the structure of the first example, differing only in that the second microstructure 50 and light-shielding layer 60 are no longer provided. Instead, the first surface of the dielectric substrate 10 is roughened, and a first reflective layer 130 is formed on the roughened first surface to achieve the same functions as the second microstructure 50 and light-shielding layer 60. Specifically, the dielectric substrate 10 has a first surface facing the light-emitting chip. The first surface has a flat region and a groove region. The first groove is located in the groove region. The flat region of the first surface is roughened, and the first reflective layer 130 is disposed on the roughened surface near the light-emitting chip. In this case, light emitted by the color conversion pattern 30 is further dispersed upon striking the roughened surface and then reflected by the first reflective layer 130, resulting in a more uniform light.

[0115] In some examples, the material of the first reflective layer 130 includes, but is not limited to, silver (Ag).

[0116] It should be noted that in the second to fifth examples, the second microstructure 50 and the light shielding layer 60 can be replaced by a rough surface and a first reflective layer 130, and these structures are also within the protection scope of the embodiments of the present disclosure.

[0117] The embodiment of the present disclosure provides a display device, which may include any of the above-mentioned backlight structures and, of course, may also include a display panel located on the light-emitting side of the backlight structure.

[0118] The display device may be any product or component with a display function, such as a mobile phone, a tablet computer, a television, a monitor, a laptop computer, a digital photo frame, a navigator, etc., but the embodiment of the present invention is not limited thereto.

[0119] It will be understood that the above embodiments are merely exemplary embodiments for illustrating the principles of the present invention, and the present invention is not limited thereto. Those skilled in the art will appreciate that various modifications and improvements can be made without departing from the spirit and substance of the present invention, and such modifications and improvements are also considered to be within the scope of protection of the present invention.

Claims

1. A light-emitting substrate, comprising: A dielectric substrate having a plurality of first grooves; A plurality of light-emitting chips are arranged on the dielectric substrate; and The color conversion layer includes a plurality of color conversion patterns and is located on the light-emitting sides of the plurality of light-emitting chips; wherein at least one of the color conversion patterns is located in the first groove.

2. The light-emitting substrate according to claim 1, wherein: It also includes a first microstructure disposed between the light emitting chip and the color conversion pattern, and a certain distance is provided between the first microstructure and the dielectric substrate, and is configured to gather the light emitted by the light emitting chip and transmit it to the color conversion pattern.

3. The light-emitting substrate according to claim 1, wherein: It also includes a first microstructure disposed on the dielectric substrate and located on a side of the color conversion pattern close to the light-emitting chip, and a certain distance is provided between the first microstructure and the light-emitting chip, and is configured to gather the light emitted by the light-emitting chip and transmit it to the color conversion pattern.

4. The light-emitting substrate according to claim 3, wherein: The dielectric substrate is provided with a plurality of second grooves, and a lens assembly of the first microstructure is arranged in one of the second grooves.

5. The light emitting substrate according to claim 3, wherein: The color conversion pattern includes a plurality of color conversion units arranged at intervals; the first groove includes a plurality of first sub-grooves arranged at intervals, and one of the color conversion units is arranged in one of the first sub-grooves; and the lens components of the first microstructure are arranged in one-to-one correspondence with the color conversion units.

6. The light emitting substrate according to claim 1, wherein: The color conversion pattern includes multiple sub-color conversion layers and multiple transparent film layers, which are stacked and alternately arranged; the light emitted by the light-emitting chip is transmitted and reflected at the interface between the sub-color conversion layer and the transparent film layer.

7. The light-emitting substrate according to claim 1, wherein: It also includes a semi-transmissive and semi-reflective film layer located on the side of the color conversion pattern away from the light-emitting chip, and is configured to transmit a part of the light emitted by the light-emitting chip and reflect the other part.

8. The light emitting substrate according to claim 1, wherein: The light-emitting chip is configured to emit light of a first color, and the light of the first color excites the color conversion layer to emit light of a second color and light of a third color; the light-emitting substrate also includes a distributed Bragg reflector located on the side of the color conversion layer away from the light-emitting chip; the reflectivity of the distributed Bragg reflector to the light of the second color and the reflectivity of the light of the third color are both lower than the reflectivity to the light of the first color; and the transmittance of the distributed Bragg reflector to the light of the second color and the transmittance of the light of the third color are both higher than the transmittance to the light of the first color.

9. The light emitting substrate according to claim 8, wherein: The distributed Bragg reflector includes titanium dioxide film layers and zinc oxide film layers alternately arranged in sequence along a direction away from the color conversion pattern stacking direction; or, the distributed Bragg reflector includes zinc oxide film layers and silicon dioxide film layers alternately arranged in sequence along a direction away from the color conversion pattern stacking direction.

10. The light emitting substrate according to claim 1, wherein: The dielectric substrate has a first surface facing the light-emitting chip, the first surface has a flat area and a groove area; the first groove is located in the groove area; the flat area of ​​the first surface is a rough surface, and a first reflective layer is arranged on the rough surface close to the light-emitting chip.

11. The light emitting substrate according to claim 1, wherein: The dielectric substrate has a first surface facing the light emitting chip; The light-emitting substrate further comprises: a second microstructure and a light-shielding layer which are arranged on the first surface and are sequentially arranged in a direction close to the light-emitting chip; The second microstructure is configured to diffuse the light emitted from the color conversion layer; the light-emitting substrate also includes a plurality of first openings, the first openings penetrate the second microstructure and the light-shielding layer, and the light emitted from the light-emitting chip can pass through the first openings to illuminate the color conversion pattern.

12. The light emitting substrate according to claim 1, wherein: An orthographic projection of one of the first grooves on the plane where the dielectric substrate is located covers an orthographic projection of one of the first openings on the plane where the dielectric substrate is located.

13. The light emitting substrate according to claim 1, wherein: It also includes a first lead end and a second lead end which are arranged on the dielectric substrate and are respectively arranged on two opposite sides of the first groove; the first connection pad of the light-emitting chip is connected to the first lead end, and the second connection pad of the light-emitting chip is connected to the second lead end.

14. The light emitting substrate according to claim 13, wherein: The first connection pad is arranged toward the first lead end, and the two are directly connected; the second connection pad is arranged toward the second lead end, and the two are directly connected.

15. The light emitting substrate according to claim 13, wherein: The first connection pad is disposed away from the first lead end, and the two are connected through a first signal line; the second connection pad is disposed away from the second lead end, and the two are connected through a second signal line.

16. The light-emitting substrate according to any one of claims 1 to 13, wherein: The invention also includes a scattering layer located on a side of the color conversion pattern away from the light emitting chip.

17. The light-emitting substrate according to any one of claims 1 to 13, wherein: Also included is an encapsulation layer for covering the color conversion layer.

18. The light-emitting substrate according to any one of claims 1 to 13, wherein: It also includes a second reflective layer arranged on a side of the light emitting chip away from the dielectric substrate.

19. The light-emitting substrate according to any one of claims 1 to 13, wherein: The material of the color conversion layer includes quantum dots or fluorescent powder.

20. A display device comprising the light-emitting substrate according to any one of claims 1 to 19.

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