Disclosure of Invention
In view of the above, the present disclosure is directed to a display panel capable of improving light conversion efficiency and a method for manufacturing the same.
The application provides a display panel, it includes: the light-emitting diode comprises a first substrate, a second substrate arranged opposite to the first substrate, and a blue light emitting layer and a color conversion layer which are arranged between the first substrate and the second substrate in a stacked mode, wherein the color conversion layer is arranged on the light emitting side of the blue light emitting layer, the color conversion layer comprises a plurality of diffusion pixel units, each diffusion pixel unit comprises a matrix, and first scattering particles and second scattering particles which are dispersed in the matrix, the first scattering particles are located on the side, close to the blue light emitting layer, of the color conversion layer, the second scattering particles are located on the side, far away from the blue light emitting layer, of the color conversion layer, the molar concentration of the first scattering particles is smaller than that of the second scattering particles, and the particle size of the first scattering particles is larger than that of the second scattering particles.
In one embodiment, the first scattering particles and the second scattering particles are continuously distributed in a direction from a side of the diffusion pixel unit close to the blue light emitting layer toward a side far from the blue light emitting layer.
In one embodiment, the matrix includes a first film layer and a second film layer disposed in a stack, the first scattering particles being dispersed in the first film layer and the second scattering particles being dispersed in the second film layer.
In one embodiment, the first scattering particles dispersed in each of the first film layers have the same particle size and molar concentration, and the second scattering particles dispersed in each of the second film layers have the same particle size and molar concentration.
In one embodiment, the first scattering particles and the second scattering particles have a gradually decreasing particle diameter in a direction from a side of the diffusion pixel unit closer to the blue light emitting layer toward a side farther from the blue light emitting layer.
In one embodiment, the molar concentrations of the first scattering particles and the second scattering particles are gradually increased in a direction from a side of the diffusion pixel unit close to the blue light emitting layer to a side far from the blue light emitting layer.
In one embodiment, the color conversion layer includes a red pixel unit, a green pixel unit and a blue pixel unit arranged in an array, the red pixel unit and the green pixel unit include a color conversion material in a matrix, the blue pixel unit does not include a color conversion material in a matrix, and the blue pixel unit is the diffusion pixel unit.
In one embodiment, the diffusion pixel unit further includes the red pixel unit and the green pixel unit, the first scattering particles in the red pixel unit and the green pixel unit have a smaller particle size and a higher molar concentration than the first scattering particles in the blue pixel unit on a side close to the blue light emitting layer, and the second scattering particles in the red pixel unit and the green pixel unit have a larger particle size and a lower molar concentration than the second scattering particles in the blue pixel unit on a side away from the blue light emitting layer.
The application provides a manufacturing method of a display panel, which comprises the following steps:
providing a first substrate and a second substrate arranged opposite to the first substrate; and
forming a blue light emitting layer on the first substrate, forming a color conversion layer on the first substrate or the second substrate, and bonding the first substrate and the second substrate to enable the color conversion layer to be positioned on the light emitting side of the blue light emitting layer;
wherein the color conversion layer includes a plurality of diffusion pixel units, and the step of forming the diffusion pixel units includes:
mixing the first scattering particles in a matrix solution, patterning and curing into a first film layer through a wet process;
mixing second scattering particles in a matrix solution, patterning and curing the second scattering particles on the first film layer into a second film layer through a wet process;
the first scattering particles and the second scattering particles are respectively one of first scattering particles and second scattering particles,
the film layer formed by the first scattering particles is positioned on one side of the color conversion layer close to the blue light emitting layer, the film layer formed by the second scattering particles is positioned on one side of the color conversion layer far away from the blue light emitting layer,
the molar concentration of the first scattering particles is less than that of the second scattering particles, and the particle size of the first scattering particles is greater than that of the second scattering particles.
In one embodiment, the step of forming the diffusion pixel cell further comprises: the method further includes the step of patterning and curing the matrix solution on the first film layer into a matrix film layer by a wet process prior to the step of mixing the second scattering particles in the matrix solution, patterning and curing the second scattering particles on the first film layer into a second film layer by a wet process.
The organic light emitting diode display panel has the advantages that the first scattering particles and the second scattering particles are added in the blue pixel unit, the first scattering particle films with large sizes and low molar concentrations are dispersed on the light inlet side, namely the side close to the blue light emitting layer, the blue light is converged and enhanced to be emitted to the light outlet side, and excitation of a color conversion material is promoted. At the light-emitting side, namely, keep away from blue light luminescent layer one side, the second scattering particle film that has small-size, high molar concentration disperses, and the reinforcing light scattering promotes light extraction efficiency, can solve the blue pixel unit visual angle and little, the luminance low problem of. In addition, first and second scattering particles may be added to the green and red pixel cells to improve light efficiency.
Detailed Description
The technical solution in the present application will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present application. It should be apparent that the described embodiments are only some embodiments of the present application, and not all embodiments. All other embodiments, which can be obtained by a person skilled in the art without making any inventive step based on the embodiments in the present application, are within the scope of protection of the present application.
Referring to fig. 1, adisplay panel 100 according to a first embodiment of the present disclosure includes afirst substrate 10, asecond substrate 20 disposed opposite to thefirst substrate 10, and a bluelight emitting layer 30 and a patterned color conversion layer 40 stacked between thefirst substrate 10 and thesecond substrate 20. The color conversion layer 40 is disposed on the light-emitting side of the blue light-emittinglayer 30. In the present embodiment, the bluelight emitting layer 30 is disposed on thefirst substrate 10. The color conversion layer 40 is disposed on thesecond substrate 20. In another embodiment, the bluelight emitting layer 30 and the color conversion layer 40 may both be disposed on thefirst substrate 10. Thedisplay panel 100 may further include acolor filter layer 50 disposed between thesecond substrate 20 and the color conversion layer 40.
The bluelight emitting layer 30 includes a plurality of bluelight emitting parts 31 arranged in an array and alight shielding layer 32 disposed between the adjacent bluelight emitting parts 31. The blueLight Emitting part 31 may be a blue Organic Light-Emitting Diode device (OLED) or a blue Micro Light-Emitting Diode device (Micro LED). The light-shielding layer 32 may be a black matrix.
The color conversion layer 40 includes a plurality ofdiffusion pixel units 41. Thediffusion pixel unit 41 may be selected from one or more of a red pixel unit, a green pixel unit, and a blue pixel unit. For example, in the present embodiment, the color conversion layer 40 includes a plurality ofred pixel cells 41R,green pixel cells 41G, andblue pixel cells 41B arranged in an array, andspacers 42 disposed between adjacent diffusion pixel cells. Each of thered pixel cells 41R, each of thegreen pixel cells 41G, and each of theblue pixel cells 41B are provided in one-to-one correspondence with one of the bluelight emitting sections 31. In this embodiment, thediffusion pixel unit 41 is referred to as ablue pixel unit 41B. It is understood that the color conversion layer 40 may further include a yellow pixel unit and a white pixel unit, and at this time, thediffusion pixel unit 41 may be selected from one or more of a red pixel unit, a green pixel unit, a blue pixel unit, a yellow pixel unit, and a white pixel unit.
Thediffusion pixel unit 41 includes amatrix 411 and first andsecond scattering particles 412 and 413 dispersed in thematrix 411. Thesubstrate 411 is a film containing a color conversion material or a transparent film containing no color conversion material. The color conversion material may be a phosphor, quantum dot, perovskite, or the like. In this embodiment, thehost 411 used for theblue pixel unit 41B does not color-convert the light emitted from the blue light emitting layer 40, and thehost 411 is a transparent thin film containing no color conversion material. Thehost 411 for thered pixel unit 41R and thegreen pixel unit 41G is used for color conversion of light emitted from the blue light emitting layer 40, that is, for emitting red or green light under excitation of blue light emitted from the blue light emitting layer 40. In this case, thesubstrate 411 is a thin film including phosphor, quantum dots, or perovskite. In other embodiments, thehost 411 for theblue pixel unit 41B may emit blue light under excitation of blue light emitted from the blue light emitting layer 40, and in this case, thehost 411 is a thin film including phosphor, quantum dot, or perovskite.
Depending on the manufacturing method, thematrix 411 may be a uniform, continuous film in which thefirst scattering particles 412 and thesecond scattering particles 413 are sequentially dispersed. As shown in fig. 2, thesubstrate 411 includes at least one first membrane layer 4111 and at least onesecond membrane layer 4112 arranged in a stack. Thefirst scattering particles 412 are dispersed in the first layer 4111, and thesecond scattering particles 412 are dispersed in thesecond layer 4112. The particle size and molar concentration of the dispersed first scatteringparticles 412 in each first film layer 4111 are the same or approximately the same. The particle size and molar concentration of thesecond scattering particles 413 dispersed in eachsecond film layer 4112 are the same or about the same. Thefirst scattering particles 412 are located on the color conversion layer 40 side close to the bluelight emitting layer 30. Thesecond scattering particles 413 are located on the side of the color conversion layer 40 away from the bluelight emitting layer 30. Wherein, the molar concentration of thefirst scattering particles 412 is less than the molar concentration of thesecond scattering particles 413. Thefirst scattering particles 412 have a larger particle size than thesecond scattering particles 413. In one embodiment, the average particle size of thefirst scattering particles 412 may be made larger than the average particle size of thesecond scattering particles 413. In another embodiment, the minimum particle size of thefirst scattering particles 412 may be larger than the maximum particle size of thesecond scattering particles 413.
The particle diameter of thefirst scattering particles 412 gradually becomes smaller in a direction from the side of thediffusion pixel unit 41 closer to the bluelight emitting layer 30 toward the side farther from the bluelight emitting layer 30. The particle diameter of thesecond scattering particles 412 becomes gradually smaller in a direction from the side of thediffusion pixel unit 41 closer to the blue light-emittinglayer 30 toward the side farther from the blue light-emittinglayer 30. The molar concentration of thefirst scattering particles 412 is gradually increased in a direction from the side of thediffusion pixel unit 41 closer to the bluelight emitting layer 30 toward the side farther from the bluelight emitting layer 30. The molar concentration of thesecond scattering particles 413 gradually becomes larger in a direction from the side of thediffusion pixel unit 41 closer to the bluelight emitting layer 30 toward the side farther from the bluelight emitting layer 30. Thefirst scattering particles 412 and thesecond scattering particles 413 are selected from one or more organic scattering particles such as organic silicon, polystyrene and polycarbonate or from one or more inorganic scattering particles such as titanium dioxide, zirconium dioxide, vanadium dioxide, tin dioxide, aluminum oxide and barium titanate. The particle diameters of the first scattering particles and the second scattering particles are 10nm-2500 nm.
In the present embodiment, thefirst scattering particles 412 and thesecond scattering particles 413 are continuously distributed in a direction from the side of thediffusion pixel unit 41 closer to the bluelight emitting layer 30 toward the side farther from the bluelight emitting layer 30. In another embodiment, thefirst scattering particles 412 and thesecond scattering particles 413 may be non-continuously distributed, that is, thefirst scattering particles 412 with large size and low molar concentration are dispersed only on the light incident side, that is, the side close to the bluelight emitting layer 30, and thesecond scattering particles 413 with small size and high molar concentration are dispersed only on the light emitting side, that is, the side far from the bluelight emitting layer 30.
In the embodiment, red and green light is generated by exciting the color conversion material, and blue light is directly emitted from the blue light backlight source, so that the viewing angle and brightness of the blue light are smaller than those of the red and green light, and color cast and lower brightness and dark picture are caused in side view. The film containing large-size and low-concentration scattering particles is formed on the side close to the blue light backlight source, namely the light incident side, and the forward emergence of the blue light is converged and enhanced; the scattering particle film with small size and high concentration is formed on the light-emitting side far away from the blue light backlight source, so that the light scattering is enhanced, and the light-emitting efficiency and the visual angle are improved.
In the present embodiment, only the first andsecond scattering particles 412 and 413 are added to theblue pixel cell 41B, and the first andsecond scattering particles 412 and 413 are not added to the red andgreen pixel cells 41R and 41G. In another embodiment of the present application, referring to fig. 3, in order to improve the light efficiency of thered pixel unit 41R and thegreen pixel unit 41G, thefirst scattering particles 412 and thesecond scattering particles 413 are also added to thered pixel unit 41R and thegreen pixel unit 41G. In order to balance the luminance difference between the pixel units, the particle diameters and molar concentrations of thefirst scattering particles 412 and thesecond scattering particles 413 added to thered pixel unit 41R and thegreen pixel unit 41G may be adjusted to be different from those of thefirst scattering particles 412 and thesecond scattering particles 413 added to theblue pixel unit 41B. For example, on the side close to the bluelight emitting layer 30, thefirst scattering particles 412 in thered pixel unit 41R and thegreen pixel unit 41G have a smaller particle size than thefirst scattering particles 412 in theblue pixel unit 41B and a higher molar concentration than thefirst scattering particles 412 in theblue pixel unit 41B. On the side away from the bluelight emitting layer 30, thesecond scattering particles 413 in thered pixel unit 41R and thegreen pixel unit 41G have a larger particle size than thesecond scattering particles 413 in theblue pixel unit 41B and a lower molar concentration than thesecond scattering particles 413 in theblue pixel unit 41B.
Referring to fig. 2 and fig. 4 together, a second embodiment of the present application further provides a method for manufacturing a display panel, which can be used to manufacture thedisplay panel 100 of the present application.
The manufacturing method comprises the following steps:
providing afirst substrate 10 and asecond substrate 20 disposed opposite to thefirst substrate 10; and
the bluelight emitting layer 30 is formed on thefirst substrate 10, the color conversion layer 40 is formed on thefirst substrate 10 or thesecond substrate 20, and thefirst substrate 10 and thesecond substrate 20 are bonded to each other such that the color conversion layer 40 is positioned on the light emitting side of the bluelight emitting layer 30.
In this embodiment mode, the color conversion layer 40 is formed on thesecond substrate 20. In another embodiment, the bluelight emitting layer 30 and the color conversion layer 40 may be both formed on thefirst substrate 10. In addition, the manufacturing method of the display panel may further include a step of forming thecolor filter layer 50 on thesecond substrate 20 before forming the color conversion layer 40.
The bluelight emitting layer 30 includes a plurality of bluelight emitting parts 31 arranged in an array and alight shielding layer 32 disposed between the adjacent bluelight emitting parts 31. The bluelight emitting section 31 may be a blue organic light emitting diode device or a blue micro light emitting diode device. The light-shielding layer 32 may be a black matrix.
The color conversion layer 40 includes a plurality ofdiffusion pixel units 41. Thediffusion pixel unit 41 may be selected from one or more of a red pixel unit, a green pixel unit, and a blue pixel unit. For example, in the present embodiment, the color conversion layer 40 includes a plurality ofred pixel cells 41R,green pixel cells 41G, andblue pixel cells 41B arranged in an array, andspacers 42 disposed between adjacent diffusion pixel cells. Each of thered pixel cells 41R, each of thegreen pixel cells 41G, and each of theblue pixel cells 41B are provided in one-to-one correspondence with one of the bluelight emitting sections 31. In this embodiment, thediffusion pixel unit 41 is referred to as ablue pixel unit 41B. It is understood that the color conversion layer 40 may further include a yellow pixel unit and a white pixel unit, and at this time, thediffusion pixel unit 41 may be selected from one or more of a red pixel unit, a green pixel unit, a blue pixel unit, a yellow pixel unit, and a white pixel unit.
Thediffusion pixel unit 41 includes amatrix 411 and first andsecond scattering particles 412 and 413 dispersed in thematrix 411. Thesubstrate 411 is a film containing a color conversion material or a transparent film containing no color conversion material. The color conversion material may be a phosphor, quantum dot, perovskite, or the like.
In this embodiment, thehost 411 used for theblue pixel unit 41B does not color-convert the light emitted from the blue light emitting layer 40, and thehost 411 is a transparent thin film containing no color conversion material. Thesubstrates 411 for thered pixel unit 41R and thegreen pixel unit 41G are used for color conversion of light emitted from the blue light emitting layer 40, that is, for emission of red or green light under excitation of blue light emitted from the blue light emitting layer 40. In this case, thesubstrate 411 is a thin film including phosphor, quantum dots, or perovskite. In other embodiments, thehost 411 for theblue pixel unit 41B may emit blue light under excitation of blue light emitted from the blue light emitting layer 40, and in this case, thehost 411 is a thin film including phosphor, quantum dot, or perovskite.
Wherein the color conversion layer 40 includes a plurality ofdiffusion pixel units 41. Referring to fig. 5, the step of forming thediffusion pixel unit 41 includes:
mixing thefirst scattering particles 412 in a matrix solution, patterning and curing into a first film layer 4111 by a wet process; this step may also be repeated multiple times, and thefirst scattering particles 412 with different particle sizes and/or molar concentrations are mixed in the matrix solution to form a plurality of first film layers 4111; the wet process may be an ink jet printing or a photo etching process.
Mixing thesecond scattering particles 413 in a matrix solution, patterning and curing thesecond film layer 4112 on the first film layer through a wet process; this step may be repeated a plurality of times, and the second scattering particles with different particle sizes and/or molar concentrations are mixed in the matrix solution to form a plurality of second film layers 4112.
The first scattering particle and the second scattering particle are one of thefirst scattering particle 412 and thesecond scattering particle 413, respectively.
The film layer formed by thefirst scattering particles 412 is located on the side of the color conversion layer 40 close to the bluelight emitting layer 30, and the film layer formed by thesecond scattering particles 413 is located on the side of the color conversion layer 40 far from the bluelight emitting layer 30. Wherein, the molar concentration of thefirst scattering particles 412 is less than the molar concentration of thesecond scattering particles 413. Thefirst scattering particles 412 have a larger particle size than thesecond scattering particles 413. In one embodiment, the average particle size of thefirst scattering particles 412 may be larger than the average particle size of thesecond scattering particles 413. In another embodiment, the minimum particle size of thefirst scattering particles 412 may be larger than the maximum particle size of thesecond scattering particles 413. When the color conversion layer 40 is formed on thesecond substrate 20, a film layer of thesecond scattering particles 413 may be formed first, and then a film layer of thefirst scattering particles 412 may be formed. When the color conversion layer 40 is formed on thefirst substrate 10, a film layer of thefirst scattering particles 412 may be formed first, and then a film layer of thesecond scattering particles 413 may be formed.
In the color conversion layer 40 formed according to this method, thesubstrate 411 includes a first film layer 4111 and asecond film layer 4112 which are stacked. Thefirst scattering particles 412 are dispersed in the first film layer 4111, and the particle size and molar concentration of thefirst scattering particles 412 dispersed in each first film layer 4111 in thesecond film layer 4112 are the same or about the same. Thesecond scattering particles 413 dispersed in eachsecond film layer 4112 have the same or approximately the same particle size and molar concentration. Further, the particle diameter of thefirst scattering particles 412 gradually becomes smaller in a direction from the side of thediffusion pixel unit 41 closer to the bluelight emitting layer 30 toward the side farther from the bluelight emitting layer 30. The particle diameter of thesecond scattering particles 412 becomes gradually smaller in a direction from the side of thediffusion pixel unit 41 closer to the blue light-emittinglayer 30 toward the side farther from the blue light-emittinglayer 30. The molar concentration of thefirst scattering particles 412 is gradually increased in a direction from the side of thediffusion pixel unit 41 closer to the bluelight emitting layer 30 toward the side farther from the bluelight emitting layer 30. The molar concentration of thesecond scattering particles 413 gradually becomes larger in a direction from the side of thediffusion pixel unit 41 closer to the bluelight emitting layer 30 toward the side farther from the bluelight emitting layer 30. Thefirst scattering particles 412 and thesecond scattering particles 413 are selected from one or more organic scattering particles such as organic silicon, polystyrene and polycarbonate or from one or more inorganic scattering particles such as titanium dioxide, zirconium dioxide, vanadium dioxide, tin dioxide, aluminum oxide and barium titanate. The particle diameters of the first scattering particles and the second scattering particles are 10nm-2500 nm.
In the present embodiment, thefirst scattering particles 412 and thesecond scattering particles 413 are continuously distributed in a direction from the side of thediffusion pixel unit 41 close to the bluelight emitting layer 30 toward the side far from the bluelight emitting layer 30.
In another embodiment, referring to fig. 6, the step of forming the diffusion pixel unit includes:
mixing thefirst scattering particles 412 in a matrix solution, patterning and curing into a first film layer 4111 by a wet process; this step may also be repeated multiple times;
patterning and curing the matrix solution on the first film layer into a matrix film layer through a wet process;
the second scattering particles are mixed in the matrix solution, and patterned and cured on the matrix film layer to form thesecond film layer 4112 by a wet process, which may also be repeated multiple times.
Thefirst scattering particles 412 and thesecond scattering particles 413 of the color conversion layer thus formed are discontinuously distributed, i.e., thefirst scattering particles 412 having a large size and a low molar concentration are dispersed only on the light incident side, i.e., the side close to the bluelight emitting layer 30, and thesecond scattering particles 413 having a small size and a high molar concentration are dispersed only on the light emitting side, i.e., the side away from the bluelight emitting layer 30.
In the present embodiment, thefirst scattering particles 412 and thesecond scattering particles 413 are added only to theblue pixel cell 41B, and thefirst scattering particles 412 and thesecond scattering particles 413 are not added to thered pixel cell 41R and thegreen pixel cell 41G. In other embodiments of the present invention, thefirst scattering particles 412 and thesecond scattering particles 413 are also added to thered pixel unit 41R and thegreen pixel unit 41G in order to improve the light efficiency of thered pixel unit 41R and thegreen pixel unit 41G. In order to balance the luminance difference between the pixel units, the particle diameters and molar concentrations of the first andsecond scattering particles 412 and 413 added to the red andgreen pixel units 41R and 41G may be adjusted to be different from those of the first andsecond scattering particles 412 and 413 added to theblue pixel unit 41B. For example, on the side close to the bluelight emitting layer 30, thefirst scattering particles 412 in thered pixel unit 41R and thegreen pixel unit 41G have a smaller particle size than thefirst scattering particles 412 in theblue pixel unit 41B and a higher molar concentration than thefirst scattering particles 412 in theblue pixel unit 41B. On the side away from the bluelight emitting layer 30, thesecond scattering particles 413 in thered pixel unit 41R and thegreen pixel unit 41G have a larger particle size than thesecond scattering particles 413 in theblue pixel unit 41B and a lower molar concentration than thesecond scattering particles 413 in theblue pixel unit 41B.
The organic light emitting diode display panel has the advantages that the first scattering particles and the second scattering particles are added in the blue pixel unit, the first scattering particle films with large sizes and low molar concentrations are dispersed on the light inlet side, namely the side close to the blue light emitting layer, the blue light is converged and enhanced to be emitted to the light outlet side, and excitation of a color conversion material is promoted. The second scattering particle film with small size and high molar concentration is dispersed on the light emitting side, namely the side far away from the blue light emitting layer, so that light scattering is enhanced, the light emitting efficiency is improved, and the problems of small visual angle and low brightness of a blue pixel unit can be solved. In addition, first scattering particles and second scattering particles may be added to the green pixel cell and the red pixel cell to improve light efficiency.
The foregoing provides a detailed description of embodiments of the present application, and the principles and embodiments of the present application have been described herein using specific examples, which are presented only to aid in the understanding of the present application. Meanwhile, for those skilled in the art, according to the idea of the present application, there may be variations in the specific embodiments and the application scope, and in summary, the content of the present specification should not be construed as a limitation to the present application.