CN115513260A - OLED display panel, mask set thereof and preparation method - Google Patents

Abstract

The application discloses an OLED display panel, a mask set of the OLED display panel and a preparation method of the OLED display panel. The OLED display panel comprises a substrate and a plurality of pixel units, wherein each pixel unit comprises an anode, a cathode and a light-emitting layer; the luminous layer defines a main luminous zone and an edge luminous zone, the edge luminous zone is positioned beside the main luminous zone, and the luminous layer comprises a main luminous part arranged corresponding to the main luminous zone and an edge luminous part arranged corresponding to the edge luminous zone; the thickness of the side light-emitting part is smaller than that of the main light-emitting part. In the application, the thickness of the main light emitting part is relatively thick, so that a strong microcavity effect can be formed in the main light emitting region, and the luminous efficiency and the color purity of the light emitting color of the main light emitting region can be improved; the thickness of the edge light-emitting part is relatively thin, the length of the microcavity at the edge light-emitting area is shortened, so that different light-emitting areas in the light-emitting layer form different lengths of the microcavity and emit different light-emitting wavelengths, the emitted light of the light-emitting layer is favorably dispersed, and the purpose of improving the visual angle color cast is achieved.

Description

OLED display panel, mask set thereof and preparation method

Technical Field

The application relates to the technical field of organic light-emitting display equipment, in particular to an OLED display panel, a mask set of the OLED display panel and a preparation method of the OLED display panel.

Background

An OLED (Organic Light-Emitting Diode) display panel has the characteristics of being thinner, lighter, higher in brightness, lower in power consumption, fast in response, higher in definition, higher in flexibility, higher in Light-Emitting efficiency and the like, and meets the user requirements, and thus is widely applied to the market.

The OLED display panel comprises a top light-emitting structure, and the top light-emitting structure can improve the light-emitting efficiency and the color purity of light-emitting color by utilizing a stronger microcavity effect. However, the microcavity effect causes the display brightness to decay rapidly at large viewing angles, and the color shift is severe. Especially, the area of the AA area of the OLED display panel corresponding to the large size is relatively large, so that the viewing angle range of the user is correspondingly increased, which causes the problems of chromaticity deviation and brightness deviation of the OLED display panel due to the large viewing angle to be more apparent.

Disclosure of Invention

The embodiment of the application provides an OLED display panel, a mask set of the OLED display panel and a preparation method of the OLED display panel, and aims to solve the problems of chromaticity deviation and brightness deviation under a large viewing angle caused by a microcavity effect.

The embodiment of the application provides an OLED display panel, which comprises a substrate and a plurality of pixel units arranged on the substrate, wherein at least one pixel unit comprises an anode, a cathode and a light-emitting layer arranged between the anode and the cathode;

the luminous layer defines a main luminous area and an edge luminous area, the main luminous area at least covers the middle part of the luminous layer, the edge luminous area is positioned beside the main luminous area, and the luminous layer comprises a main luminous part arranged corresponding to the main luminous area and an edge luminous part arranged corresponding to the edge luminous area;

wherein the thickness of the side light-emitting part is smaller than the thickness of the main light-emitting part.

According to an embodiment of the present application, the side light-emitting portion is provided with a gradually decreasing thickness in a direction away from the main light-emitting portion.

According to an embodiment of the present application, the light emitting layer includes a functional material layer and a host material layer stacked in a thickness direction thereof;

the functional material layer and/or the main body material layer define the main light emitting portion and the side light emitting portion.

According to an embodiment of the application, the side light emitting areas are circumferentially arranged along the circumference of the main light emitting area.

According to an embodiment of the present application, the area of the main light emitting region is S1, the total area of the main light emitting region and the side light emitting regions is S, and the ratio of S1 to S is 85% to 95%.

According to an embodiment of the present application, the pixel unit further includes:

a hole injection layer provided between the anode and the light emitting layer;

a hole transport layer provided between the hole injection layer and the light emitting layer;

an electron blocking layer disposed between the hole transport layer and the light emitting layer;

a hole blocking layer disposed between the light emitting layer and the cathode;

an electron transport layer disposed between the hole blocking layer and the cathode; and the number of the first and second groups,

and the electron injection layer is arranged between the electron transport layer and the cathode.

In addition, in order to achieve the above object, an embodiment of the present application further provides a mask set of the OLED display panel, where the mask set includes a first precise mask, and a first mask opening is penetrated through the first precise mask along a thickness direction of the first precise mask;

the shape and the size of the first mask opening are respectively matched with those of the main light emitting area.

According to an embodiment of the application, the mask set further comprises a second precise mask, and a second mask opening penetrates through the second precise mask along the thickness direction of the second precise mask;

wherein the second mask opening is sized to cover the primary light emitting area and the edge light emitting area.

In addition, to achieve the above object, an embodiment of the present application further provides a method for manufacturing an OLED display panel, including:

providing a substrate, and preparing an anode on the substrate;

providing a mask plate group comprising a first precise mask plate, and forming a light-emitting layer on the anode through evaporation of the mask plate group, wherein a main light-emitting part is formed through evaporation of a first mask opening of the first precise mask plate, and an edge light-emitting part is formed through evaporation of a mask shadow area of the first precise mask plate;

and preparing a cathode on the light-emitting layer.

According to one embodiment of the application, the mask set comprises a first precise mask and a second precise mask;

providing a mask plate group comprising a first precise mask plate, and forming a light-emitting layer on the anode by evaporation through the mask plate group, wherein the step of forming a main light-emitting part by evaporation through a first mask opening of the first precise mask plate and the step of forming an edge light-emitting part by evaporation through a mask shadow area of the first precise mask plate comprise the following steps:

providing a first precise mask, and forming a functional material layer on the anode through evaporation by the first precise mask, wherein a main light emitting part is formed through evaporation of a first mask opening of the first precise mask, and an edge light emitting part is formed through evaporation of a mask shadow area of the first precise mask;

and providing a second precise mask, and preparing and forming a main body material layer covering the main light-emitting part and the edge light-emitting part on the functional material layer through a second mask opening of the second precise mask.

The beneficial effects of the embodiment of the application are as follows: the cathode and the anode in the pixel unit form a micro-cavity structure, and the cavity length of the micro-cavity structure can be correspondingly adjusted by setting the thickness of any film layer between the cathode and the anode, so that the micro-cavity effect with different strengths is formed. According to the light-emitting device, the thickness of the edge light-emitting part is smaller than that of the main light-emitting part, so that on one hand, the main light-emitting part is relatively thick, a strong microcavity effect can be formed in the main light-emitting area, and the improvement of the light-emitting efficiency and the color purity of light-emitting color of the main light-emitting area is facilitated; on the other hand, the thickness of the edge light-emitting part is relatively thin, so that the length of the microcavity at the edge light-emitting area is shortened, different light-emitting areas in the light-emitting layer form different microcavity lengths and different light-emitting wavelengths, and the emergent light of the light-emitting layer is favorably dispersed, and the purpose of improving the visual angle color cast is achieved.

Drawings

The technical solutions and other advantages of the present application will become apparent from the following detailed description of specific embodiments of the present application when taken in conjunction with the accompanying drawings.

Fig. 1 is a schematic partial cross-sectional view of an OLED display panel according to an embodiment of the present disclosure;

FIG. 2 is a plan view of a first embodiment of the light-emitting layer of FIG. 1;

FIG. 3 is a plan view of a second embodiment of the light-emitting layer of FIG. 1;

FIG. 4 is a plan view structural view of a third embodiment of the light-emitting layer in FIG. 1;

FIG. 5 is a block diagram of a plan view of the first precision reticle of FIG. 1 (example);

FIG. 6 is a plan view of a prior art precision mask (comparative example);

FIG. 7 is a schematic diagram showing a comparison between the examples and comparative examples in FIG. 5 with respect to the luminance viewing angle of white light;

FIG. 8 is a comparison between the brightness of the red light in the example and the comparative example in FIG. 5;

FIG. 9 is a comparison between the brightness viewing angles of the embodiment and the comparative example in FIG. 5 with respect to green light;

FIG. 10 is a comparison of the brightness viewing angles of the embodiment and the comparative example of FIG. 5 for blue light;

FIG. 11 is a schematic diagram showing a comparison of the chromaticity and viewing angles of the embodiment and the comparative example of FIG. 5 with respect to white light;

FIG. 12 is a schematic diagram showing a comparison between the examples and comparative examples in FIG. 5 with respect to the viewing angle of chromaticity of red light;

FIG. 13 is a schematic diagram showing a comparison of the chromaticity viewing angles of the examples and comparative examples of FIG. 5 with respect to green light;

FIG. 14 is a schematic diagram showing a comparison between examples and comparative examples in FIG. 5 with respect to the viewing angles of blue light;

fig. 15 is a schematic flow chart of a method for manufacturing an OLED display panel provided in the present application.

Detailed Description

The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. It should be apparent that the described embodiments are only a few embodiments of the present application, and not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present application.

Referring to fig. 1, an oled display panel 1 generally includes a substrate and a plurality of pixel units 100 disposed on the substrate. The top emission structure of each pixel unit 100 at least includes an anode 110 and a cathode 190 disposed at opposite intervals, and an emission layer 150 disposed at the interval between the anode 110 and the cathode 190. When the OLED display panel 1 is applied with an electric field, that is, when a voltage is applied to the anode 110 and the cathode 190, holes generated by the anode 110 and electrons generated by the cathode 190 move relative to each other, and migrate toward the light emitting layer 150. When the holes and the electrons meet at the light emitting layer 150, energy excitons may be generated, thereby exciting the light emitting material in the light emitting layer 150 to generate visible light and emit light from the cathode 190.

For better hole and electron injection and transport, referring to fig. 1, the pixel unit 100 further includes a hole injection layer 120 (i.e., HIL), a hole transport layer 130 (i.e., HTL), an electron blocking layer 140 (i.e., EBL), a hole blocking layer 160 (i.e., HBL), an electron transport layer 170 (i.e., ETL), and an electron injection layer 180 (i.e., EIL). The hole injection layer 120, the hole transport layer 130, the electron blocking layer 140, the light emitting layer 150, the hole blocking layer 160, the electron transport layer 170, and the electron injection layer 180 are sequentially arranged in a direction from the anode 110 to the cathode 190.

Of course, the pixel unit 100 generally further includes an encapsulation layer, and after the film structure is prepared to form the display module, the display module is encapsulated by using a film or glass, and the film or glass forms the encapsulation layer.

It is understood that, in order to realize the display light emitting function of the OLED display panel 1, the OLED display panel 1 includes at least three sub-pixels, namely, a red sub-pixel 150a, a green sub-pixel 150b, and a blue sub-pixel 150c. Each of the pixel units 100 in the above embodiments may be configured to include one of three sub-pixels, or at least two of the three sub-pixels. For convenience of understanding, in the following embodiments, the pixel unit 100 includes a sub-pixel, which may be a red sub-pixel 150a, a green sub-pixel 150b, or a blue sub-pixel 150c.

The plurality of sub-pixels are arranged in an array on the substrate, that is, at least the light emitting layer 150 in each pixel unit 100 is independently disposed. Based on this, in one embodiment, the anode 110, the hole injection layer 120, the hole transport layer 130, the electron blocking layer 140, the light emitting layer 150, the hole blocking layer 160, the electron transport layer 170, the electron injection layer 180, and the cathode 190 in each pixel unit 100 may be independently disposed; alternatively, in another embodiment, as shown in fig. 1, a plurality of single bodies are independently disposed in the light-emitting layer 150, and each single body corresponds to a sub-pixel in the pixel unit 100; the remaining anode 110, hole injection layer 120, hole transport layer 130, electron blocking layer 140, hole blocking layer 160, electron transport layer 170, electron injection layer 180, and cathode 190 are common in all pixel cells 100.

Based on any of the above embodiments, in order to improve the light emitting efficiency and the color purity of the emitted light color of the pixel unit 100, the cathode 190 may be configured as a half-reflective half-projection layer, such that a micro-cavity structure is formed between the cathode 190 and the anode 110, and the distance from the anode 110 to the cathode 190 constitutes the cavity length of the micro-cavity structure. The cathode 190 is typically a metal or metal alloy and may be, but is not limited to, between 10nm and 20nm thick, including 10nm and 20nm thick.

When the cavity length of the microcavity structure is long enough to meet the preset conditions, a strong microcavity effect can be formed between the cathode 190 and the anode 110, so that emergent rays are concentrated, the luminous efficiency is improved, and the color purity is improved; however, the microcavity effect also causes rapid attenuation of display brightness at large viewing angles, resulting in severe color shift.

Through research, the color cast of the top light-emitting structure at an oblique viewing angle is caused by a strong microcavity effect, and the microcavity effect improves the light-emitting efficiency and narrows the spectrum, and at the same time, the actual optical path difference is shortened under the oblique viewing angle, so that the spectrum is changed.

To this end, the present application provides an OLED display panel 1, which can be combined with fig. 1 and refer to the above description, the OLED display panel 1 provided herein includes a substrate and a plurality of pixel units 100 disposed on the substrate, at least one of the pixel units 100 includes an anode 110, a cathode 190, and a light emitting layer 150 disposed between the anode 110 and the cathode 190. The OLED display panel 1 may further include a hole injection layer 120, a hole transport layer 130, an electron blocking layer 140, a hole blocking layer 160, an electron transport layer 170, an electron injection layer 180, and the like, which are not described in detail.

For the light emitting layer 150, the light emitting layer 150 defines a main light emitting region 151a and a side light emitting region 151b along its plane, and the main light emitting region 151a covers at least a middle portion of the light emitting layer 150. The side light emitting region 151b is located beside the main light emitting region 151a and adjacent to the main light emitting region 151 a. It is understood that the main light emitting region 151a plays a main light emitting and main displaying role in the light emitting layer 150, so that the main light emitting region 151a needs to cover at least a desired portion of the light emitting layer 150 (for example, at least the middle portion of the light emitting layer 150) compared to the side light emitting region 151b, and the coverage area of the main light emitting region 151a is generally set to be not smaller than that of the side light emitting region 151b.

It should be noted that the main light-emitting region 151a and the side light-emitting region 151b in the light-emitting layer 150 are not limited to be marked by visible marks, and the lines between the main light-emitting region 151a and the side light-emitting region 151b in fig. 2 to 4 are only used for assisting in distinguishing the main light-emitting region 151a and the side light-emitting region 151b, and are not necessarily present in the actual product of the OLED display panel 1.

It can be understood that when the cavity length of the microcavity structure is relatively long, the microcavity effect can be enhanced to a certain extent; conversely, when the length of the microcavity structure is relatively short, the microcavity effect can be weakened to some extent. The thickness of any film layer between the cathode 190 and the anode 110 can affect the cavity length of the microcavity structure. Therefore, in the embodiment of the present application, the thickness of the film layer in the pixel unit 100 corresponding to the side light-emitting region 151b is smaller than the thickness of the film layer in the main light-emitting region 151 a.

Specifically, the above object may be achieved by decreasing the film thickness of at least one of the hole injection layer 120, the hole transport layer 130, the electron blocking layer 140, the light emitting layer 150, the hole blocking layer 160, the electron transport layer 170, and the electron injection layer 180 in a portion corresponding to the side light emitting region 151b, and/or by increasing the film thickness of at least one of the hole injection layer 120, the hole transport layer 130, the electron blocking layer 140, the light emitting layer 150, the hole blocking layer 160, the electron transport layer 170, and the electron injection layer 180 in a portion corresponding to the main light emitting region 151 a.

Thus, the cavity length of the microcavity structure corresponding to the main light emitting region 151a can be ensured to be long enough, and emergent light can be concentrated, so that the microcavity effect can be enhanced, and the display effect can be improved; meanwhile, the cavity length of the microcavity structure corresponding to the side light-emitting region 151b can be appropriately reduced, the microcavity effect formed by the side light-emitting region 151b is appropriately weakened, the main display and main light-emitting functions of the main light-emitting region 151a are not affected, light corresponding to the side light-emitting region 151b can be dispersed, and the problem of viewing deviation at oblique angles can be effectively solved.

In the process of manufacturing the OLED display panel 1, the hole injection layer 120, the hole transport layer 130, the electron blocking layer 140, the light emitting layer 150, the hole blocking layer 160, the hole transport layer 130, the electron blocking layer 140, the hole blocking layer 160, the electron transport layer 170, and the electron injection layer 180 in the electron injection layer 180, the hole injection layer 120, the hole transport layer 130, the electron blocking layer 140, the hole blocking layer 160, the electron transport layer 170, and the electron injection layer 180 are generally manufactured by a CMM (Common Metal Mask) which is a Metal Mask with a large opening, and it is difficult to distinguish a main light emitting region 151a and an edge light emitting region 151b of the light emitting layer 150 in each pixel unit 100. The light emitting layer 150 is generally formed by FMM (Fine Metal Mask), and the main light emitting region 151a and the side light emitting region 151b of the light emitting layer 150 in each pixel unit 100 can be distinguished.

In this regard, the present application further provides a light emitting layer 150 on the plane, wherein the light emitting layer 150 includes a main light emitting section 152a corresponding to the main light emitting region 151a and a side light emitting section 152b corresponding to the side light emitting region 151b. It is understood that the main light emitting region 151a is defined by the main light emitting portion 152a, and the side light emitting region 151b is defined by the side light emitting portion 152b. However, the main light-emitting section 152a is not limited to be located only in the main light-emitting region 151a, or the side light-emitting section 152b is located only in the side light-emitting region 151b, but in other suitable arrangements, for example, one end of the side light-emitting section 152b remote from the main light-emitting section 152a may be provided as a distal end portion, and the distal end portion may extend to be located outside the side light-emitting region 151b in a direction away from the main light-emitting section 152a.

Of course, in the following embodiments, the main light emitting sections 152a and the main light emitting sections 151a are in one-to-one correspondence in shape and size, and the side light emitting sections 152b and the side light emitting sections 151b are in one-to-one correspondence in shape and size, for convenience of understanding.

Further, the thickness of the side light emitting part 152b is smaller than that of the main light emitting part 152a, so that the functions are realized, and the preparation and molding of the OLED display panel 1 are facilitated. Hereinafter, description will be given mainly on the arrangement in which the thickness of the side light emitting portion 152b is smaller than that of the main light emitting portion 152a.

The beneficial effects of the embodiment of the application are as follows: the cathode 190 and the anode 110 in the pixel unit 100 form a micro-cavity structure, and the cavity length of the micro-cavity structure can be correspondingly adjusted by setting the thickness of any film layer between the cathode 190 and the anode 110, so as to form a micro-cavity effect with different strengths. By setting the thickness of the edge light-emitting part 152b to be smaller than that of the main light-emitting part 152a, on one hand, the thickness of the main light-emitting part 152a is ensured to be relatively thick, a strong microcavity effect can be formed in the main light-emitting region 151a, and the improvement of the light-emitting efficiency and the color purity of the light-emitting color of the main light-emitting region 151a is facilitated; on the other hand, by setting the thickness of the edge light-emitting part 152b to be relatively thin, the microcavity length at the edge light-emitting region 151b is shortened, so that different light-emitting regions in the light-emitting layer 150 form different microcavity lengths and emit different light-emitting wavelengths, thereby contributing to the emission of the light-emitting layer 150 and achieving the purpose of improving the viewing angle color cast.

In the above embodiment, the thickness difference is formed between the side light emitting portion 152b and the main light emitting portion 152a. Since the main light emitting section 152a performs the main display and main light emitting functions, the main light emitting section 152a is generally provided in a film structure having a uniform thickness, that is, the thickness of the main light emitting section 152a at each position in the main light emitting region 151a is kept equal or the thickness difference is within an allowable deviation range. In view of this, the present application does not limit the specific expression that the thickness of the side light-emitting portion 152b is smaller than the thickness of the main light-emitting portion 152 a:

in one embodiment, the main light emitting part 152a is a film structure with uniform thickness and has a thickness D1, and the edge light emitting part 152b is a film structure with uniform thickness and has a thickness D2, and D2 is smaller than D1. The junction between the main light emitting portion 152a and the side light emitting portion 152b may be formed with a thickness difference, or may be formed with a slope or a flat surface to provide a smooth transition therebetween.

In one embodiment, the main light emitting portion 152a is provided as a film structure with a uniform thickness and a thickness D1, and the side light emitting portion 152b is provided with a thickness gradually decreasing from D1 to D2 in a direction away from the main light emitting portion 152a, and D2 is smaller than D1.

In one embodiment, the main light emitting portion 152a is a film structure with uniform thickness and has a thickness D1, and the edge light emitting portion 152b is disposed with gradually decreasing thickness in a direction away from the main light emitting portion 152a, and is uniformly decreased from the thickness D1 to D2 (D2 is smaller than D1), or is uniformly decreased to near zero. In this way, the cavity length of the corresponding microcavity structure in the side light-emitting region 151b is gradually shortened in a direction away from the main light-emitting region 151a, and the generated microcavity effect is gradually reduced, which contributes to improving the color shift problem at an oblique angle and also prevents abrupt changes in luminance or chromaticity from occurring between the main light-emitting region 152a and the side light-emitting region 152b or between the respective portions of the side light-emitting region 152b.

In addition, referring to fig. 1, in an embodiment, the light emitting layer 150 includes a functional material layer 152 (i.e., a Prime material layer) and a Host material layer 153 (i.e., a Host material layer) stacked along a thickness direction thereof. The functional material layer 152 mainly plays a role in efficiently transporting carriers and enhancing a host material, and specifically, the functional material helps to block electrons and prevent the electrons and holes from being combined in a hole film layer to reduce the light emitting efficiency; and also helps to lower the barrier between the hole transport layer 130 and the host material layer 153, facilitating hole transport. The functional material layer 152 and the main material layer 153 correspond to the red sub-pixel 150a, the green sub-pixel 150b, and the blue sub-pixel 150c, respectively.

Based on this, the main light-emitting portion 152a and the side light-emitting portion 152b described above in the present application may be configured to be defined only by the functional material layer 152 according to practical situations, that is, the functional material layer 152 includes the main light-emitting portion 152a and the side light-emitting portion 152b along the plane thereof; or only defined by the main body material layer 153, that is, the main body material layer 153 includes the main light emitting portion 152a and the side light emitting portion 152b along the plane thereof; or by both the functional material layer 152 and the body material layer 153.

When the main light emitting part 152a and the side light emitting part 152b are defined by the functional material layer 152 and the main material layer 153, the following may be specifically mentioned: one of the functional material layer 152 and the main body material layer 153 defines the main light emitting portion 152a, and the other of the functional material layer 152 and the main body material layer 153 defines the edge light emitting portion 152b. Alternatively, the functional material layer 152 and the main body material layer 153 each define the main light emitting portion 152a and the side light emitting portion 152b, respectively, that is, the main light emitting portion 152a includes a portion formed on the functional material layer 152 and a remaining portion formed on the main body material layer 153; the edge light emitting part 152b includes a portion formed on the functional material layer 152 and the remaining portion formed on the main material layer 153.

Of course, when the light emitting layer 150 further includes other film layers in addition to the functional material layer 152 and the main body material layer 153, and the film layers are also suitable for the manufacturing molding by the FMM, the main light emitting portion 152a and the side light emitting portion 152b may be selectively defined from at least one film layer in the light emitting layer 150, as described above.

In addition, based on any of the above embodiments, the present application does not limit the shape of the main light emitting region 151a, the shape of the side light emitting region 151b, the specific orientation relationship between the two, and the like:

referring to fig. 2, in an embodiment, the side light emitting regions 151b are circumferentially arranged along the circumference of the main light emitting region 151 a. The main light emitting region 151a may be configured to be circular, elliptical, circle-like, polygonal, or other irregular shapes according to actual requirements. The side light emitting region 151b is in a closed loop shape along the entire circumference of the main light emitting region 151a, the shape and size of the inner loop of the side light emitting region 151b are matched with the shape and size of the main light emitting region 151a one by one, and the outer loop shape and size of the side light emitting region 151b can be set according to actual requirements. Thus, the microcavity effect in the middle of the openings (i.e., the main light-emitting region 151a and the side light-emitting regions 151 b) of the sub-pixels in the light-emitting layer 150 is effectively enhanced, the microcavity effect in each edge is moderately reduced, and the color shift in each oblique viewing angle can be improved.

Referring to fig. 3, in an embodiment, the side light emitting region 151b may be disposed at a side of the main light emitting region 151 a. Based on this, the number of the side light emitting regions 151b may be set to one or at least two; when at least two side light emitting areas 151b are provided, the two side light emitting areas 151b are arranged intermittently in the circumferential direction of the main light emitting area 151 a. It can be understood that when the side light emitting regions 151b are only disposed corresponding to part of the orientations of the main light emitting regions 151a, the orientations can be selected according to actual situations, so as to improve and optimize the orientations with relatively severe color shift under oblique viewing angles, the orientations with higher requirements for brightness and chromaticity, the orientations with larger adverse effects caused by color shift problems, and the like.

Referring to fig. 4, in an embodiment, when the main light emitting region 151a is shaped in a special shape and has a concave structure, the side light emitting region 151b may be disposed at the concave structure and beside the concave structure.

Furthermore, the present application also provides an OLED display device comprising the OLED display panel 1 as described above and below. It should be noted that, for the detailed structure of the OLED display panel 1 in the OLED display device, reference may be made to the above embodiment of the OLED display panel 1, and details are not repeated herein; since the OLED display panel 1 is used in the OLED display device of the present application, embodiments of the OLED display device of the present application include all technical solutions of all embodiments of the OLED display panel 1, and the achieved technical effects are also completely the same, and are not described herein again.

In addition, the present application also provides a mask set, which is used for the preparation of the OLED display panel 1 as described above. Referring to fig. 5, in the present application, the mask set includes a first precision mask 200, and the first precision mask 200 is an FMM. The first precise mask 200 is provided with a first mask opening 210 along the thickness direction; the shape and size of the first mask opening 210 are respectively adapted to the shape and size of the main light emitting region 151 a.

In the present application, the shape and size of the first mask opening 210 are respectively adapted to the shape and size of the main light emitting region 151a, which means that the shape of the first mask opening 210 is substantially the same as the shape of the main light emitting region 151a (there may be a difference within an allowable range), and the size of the first mask opening 210 is substantially the same as the size of the main light emitting region 151a (there may be an error within an allowable range). Thus, when the anode 110 or the electron blocking layer 140 is formed and the first precise mask 200 is fixed in place, the orthographic projection area of the first mask opening 210 on the anode 110 or the electron blocking layer 140 is substantially coincident with the main light emitting area 151a of the light emitting layer 150 to be formed subsequently. At this time, when, for example, an evaporation process is employed, the main light emitting portion 152a having a uniform thickness can be formed by evaporation through the first mask opening 210. Since the FMM forms a Mask Shadow region 220 (i.e., mask Shadow) at the periphery of its Mask opening during the evaporation process. The edge light emitting part 152b having a gradually reduced thickness can be directly formed by vapor deposition through the mask shadow region 220 of the first precision mask 200, and has the characteristics of simple structure and convenient formation.

As can be seen from the above, the first mask opening 210 of the first precision mask 200 corresponds to the main light emitting portion 152a formed by vapor deposition, and the mask shadow region 220 of the first precision mask 200 corresponds to the side light emitting portion 152b formed by vapor deposition. Therefore, in order to accurately prepare the main light emitting region 152a and the side light emitting region 152b, referring to fig. 2 and 5, in an embodiment, the area of the main light emitting region 151a is S1, the total area of the main light emitting region 151a and the side light emitting region 151b is S, and the ratio of S1 to S is 85% to 95%. Thus, the area of the first mask opening 210 is also S1, and when the ratio of S1 to S is 85% to 95%, the space of the mask shadow region 220 in the region of 10% to 15% can be fully utilized, thereby reducing the light concentration in the side light emitting region 151b while ensuring the light emitting efficiency, and improving the viewing angle color shift.

It is to be understood that, when the light emitting layer 150 as a whole (for example, the functional material layer 152 and the main body material layer 153 described above) jointly defines the main light emitting portion 152a and the edge light emitting portion 152b, the mask set may include only the first precise mask 200, and the first mask openings 210 provided on the first precise mask 200 are provided in plural corresponding to the plurality of pixel units 100.

While part of the film layers (e.g., only the functional material layer 152) in the light emitting layer 150 define the main light emitting portion 152a and the edge light emitting portion 152b, the first precision reticle 200 in the reticle set may be used to form the functional material layer 152. In addition, the mask set further comprises a second precise mask (not marked in the drawing), and a second mask opening penetrates through the second precise mask along the thickness direction of the second precise mask; wherein the second mask opening is sized to cover the main light emitting region 151a and the side light emitting region 151b. In this way, the body material layer 153 covering the main light-emitting region 151a and the side light-emitting regions 151b can be directly formed by vapor deposition through the second mask openings of the second precision mask.

In addition, the application also provides a preparation method of the OLED display panel 1, and the preparation method can adopt the mask plate set to prepare and form the OLED display panel 1.

Specifically, referring to fig. 15, in the embodiment of the present application, a method for manufacturing the OLED display panel 1 includes the following steps:

step S100: providing a substrate, and preparing an anode 110 on the substrate;

in this embodiment, the anode 110 is prepared on the substrate after performing necessary operations such as cleaning on the substrate. Specifically, the anode 110 can be prepared by a PVD (Physical Vapor Deposition) process. The anode 110 may be made of a transparent conductive oxide with high work function, such as Indium Tin Oxide (ITO) or Indium Zinc Oxide (IZO).

Step S200: on the anode 110, a hole injection layer 120, a hole transport layer 130, and an electron blocking layer 140 were prepared by a first CMM, a second CMM, and a third CMM, respectively.

Step S300: providing a mask set comprising a first precise mask 200, and forming a light-emitting layer 150 on the anode 110 by evaporation through the mask set, wherein a main light-emitting part 152a is formed by evaporation through a first mask opening 210 of the first precise mask 200, and an edge light-emitting part 152b is formed by evaporation through a mask shadow area 220 of the first precise mask 200;

in this application, taking as an example that the light emitting layer 150 includes a functional material layer 152 and a body material layer 153, and the functional material layer 152 defines a main light emitting portion 152a and an edge light emitting portion 152 b:

the step 300 specifically includes:

step S310: providing a first precision mask 200, and forming a functional material layer 152 on the anode 110 by evaporation through the first precision mask 200, wherein a main light emitting part 152a is formed by evaporation through a first mask opening 210 of the first precision mask 200, and an edge light emitting part 152b is formed by evaporation through a mask shadow area 220 of the first precision mask 200;

in the present embodiment, the first precise mask 200 is selected, and the area of the first mask opening 210 is smaller than the area of the sub-pixel openings in the light-emitting layer 150 (i.e. the total area of the main light-emitting region 151a and the side light-emitting region 151 b), so as to respectively prepare the functional material layer 152 corresponding to the red sub-pixel 150a, the functional material layer 152 corresponding to the green sub-pixel 150b, and the functional material layer 152 corresponding to the blue sub-pixel 150c. In this film, the main light emitting portion 152a is formed by evaporation at the first mask opening 210 of the first precision mask 200, so that the thickness of each portion of the main light emitting portion 152a is uniform and reaches a predetermined thickness value. The side light emitting portion 152b is formed by vapor deposition from the mask shadow region 220 of the first precision mask 200, the thickness of the side light emitting portion 152b is smaller than that of the main light emitting portion 152a, and the thickness of the side light emitting portion 152b is gradually reduced in a direction away from the main light emitting portion 152a. The area of the first mask opening 210 accounts for 85% -95% of the area of the sub-pixel opening.

Step S320: a second precision mask is provided, and a main material layer 153 covering the main light-emitting portion 152a and the side light-emitting portion 152b is formed on the functional material layer 152 through a second mask opening of the second precision mask.

In this embodiment, the second precise mask is selected, that is, the area of the second mask opening is substantially the same as the area of the sub-pixel opening in the light-emitting layer 150, and the main material layer 153 corresponding to the red sub-pixel 150a, the main material layer 153 corresponding to the green sub-pixel 150b, and the main material layer 153 corresponding to the blue sub-pixel 150c are respectively prepared.

Step S400: on the light-emitting layer 150, a hole blocking layer 160, an electron transport layer 170, and an electron injection layer 180 were prepared by a fourth CMM, a fifth CMM, and a sixth CMM, respectively.

Step S500: a cathode 190 is prepared on the light emitting layer 150.

In this embodiment, the material of the cathode 190 may be selected from one or more of magnesium metal, silver metal and aluminum metal.

Step S600: the encapsulation layer is fabricated for encapsulation, and specifically, a film encapsulation or a glass encapsulation may be used, which is not described in detail.

Referring to fig. 6, the size and shape of the mask opening 210' of the FMM200' in the prior art are adapted to the size and shape of the sub-pixel opening (i.e. corresponding to the main light emitting region 151a ' and the side light emitting region 151b ') in the light emitting layer 150 '. Thus, in the evaporation process, the main light-emitting region 151a ' and the side light-emitting region 151b ' are directly formed at the positions corresponding to the mask openings 210' by evaporation, and the thicknesses of the two regions are the same. At the same time, more film structures are evaporated from the shadow region 220 'of the CMM200' beyond the extent of the sub-pixel openings.

The OLED display panel 1 prepared by the above-described method for preparing the OLED display panel 1 of the present application is used as an example, and the prior art as shown in fig. 6 is used as a comparative example.

Referring to fig. 7 to 10, the drawings respectively show the contrast data of the luminance viewing angles of the white light, the red light, the green light and the blue light emitted by the embodiment and the comparative example, and it is obvious that the OLED display panel 1 prepared by the method for preparing the OLED display panel 1 provided by the present application has a better improvement effect on the luminance viewing angle.

Referring to fig. 11 to 14, which are respectively data of comparing the chromaticity viewing angles of white light, red light, green light and blue light emitted by the embodiments and the comparative examples, it is obvious that the OLED display panel 1 prepared by the method for preparing the OLED display panel 1 provided by the present application also obtains a better improvement effect in the chromaticity viewing angle.

In the foregoing embodiments, the descriptions of the respective embodiments have respective emphasis, and for parts that are not described in detail in a certain embodiment, reference may be made to related descriptions of other embodiments.

The OLED display panel 1, the mask set thereof, and the manufacturing method thereof provided in the embodiments of the present application are described in detail above, and specific examples are applied herein to explain the principle and the implementation manner of the present application, and the description of the embodiments above is only used to help understanding the technical scheme and the core concept thereof; those of ordinary skill in the art will understand that: the technical solutions described in the foregoing embodiments may still be modified, or some technical features may be equivalently replaced; such modifications or substitutions do not depart from the spirit and scope of the present disclosure as defined by the appended claims.

Claims (10)

1. The OLED display panel is characterized by comprising a substrate and a plurality of pixel units arranged on the substrate, wherein at least one pixel unit comprises an anode, a cathode and a light-emitting layer arranged between the anode and the cathode;

the luminous layer defines a main luminous area and an edge luminous area, the main luminous area at least covers the middle part of the luminous layer, the edge luminous area is positioned beside the main luminous area, and the luminous layer comprises a main luminous part arranged corresponding to the main luminous area and an edge luminous part arranged corresponding to the edge luminous area;

wherein the thickness of the side light emitting part is smaller than that of the main light emitting part.

2. The OLED display panel of claim 1, wherein the side light-emitting portions are arranged to be gradually reduced in thickness in a direction away from the main light-emitting portion.

3. The OLED display panel claimed in claim 1, wherein the light emitting layer includes a functional material layer and a main material layer stacked in a thickness direction thereof;

the functional material layer and/or the main body material layer define the main light emitting portion and the edge light emitting portion.

4. The OLED display panel of claim 1, wherein the side light-emitting regions are circumferentially arranged along a circumference of the main light-emitting region.

5. The OLED display panel as claimed in claim 4, wherein the main light emitting region has an area of S1, the total area of the main light emitting region and the side light emitting regions is S, and a ratio of S1 to S is 85% to 95%.

6. The OLED display panel of any one of claims 1 to 5, wherein the pixel cell further comprises:

a hole injection layer provided between the anode and the light emitting layer;

a hole transport layer provided between the hole injection layer and the light emitting layer;

an electron blocking layer disposed between the hole transport layer and the light emitting layer;

a hole blocking layer disposed between the light emitting layer and the cathode;

an electron transport layer disposed between the hole blocking layer and the cathode; and the number of the first and second groups,

and the electron injection layer is arranged between the electron transport layer and the cathode.

7. The mask set of the OLED display panel according to any one of claims 1 to 6, wherein the mask set comprises a first precision mask, and the first precision mask is provided with a first mask opening along a thickness direction thereof;

the shape and the size of the first mask opening are respectively matched with those of the main light emitting area.

8. The mask set of the OLED display panel according to claim 7, wherein the mask set further includes a second precision mask having a second mask opening formed therethrough in a thickness direction thereof;

wherein the second mask opening is sized to cover the primary light emitting area and the edge light emitting area.

9. A method of manufacturing the OLED display panel according to any one of claims 1 to 6, comprising:

providing a substrate, and preparing an anode on the substrate;

providing a mask plate group comprising a first precise mask plate, and forming a light-emitting layer on the anode through evaporation of the mask plate group, wherein a main light-emitting part is formed through evaporation of a first mask opening of the first precise mask plate, and an edge light-emitting part is formed through evaporation of a mask shadow area of the first precise mask plate;

and preparing a cathode on the light-emitting layer.

10. The method of manufacturing an OLED display panel according to claim 9, wherein the set of reticles includes a first precision reticle and a second precision reticle;

providing a mask plate group comprising a first precise mask plate, and forming a light-emitting layer on the anode by evaporation through the mask plate group, wherein the step of forming a main light-emitting part by evaporation through a first mask opening of the first precise mask plate and the step of forming an edge light-emitting part by evaporation through a mask shadow area of the first precise mask plate comprise the following steps:

providing a first precise mask, and forming a functional material layer on the anode through evaporation by the first precise mask, wherein a main light-emitting part is formed through evaporation of a first mask opening of the first precise mask, and an edge light-emitting part is formed through evaporation of a mask shadow area of the first precise mask;

and providing a second precise mask, and preparing and forming a main body material layer covering the main light-emitting part and the edge light-emitting part on the functional material layer through a second mask opening of the second precise mask.

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