Display panel and display device
By setting hole transport layers with different lateral sheet resistance in the OLED display panel, the problem of inconsistent light emission brightness at low gray levels is solved, improving the display effect and reducing power consumption.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- BOE TECHNOLOGY GROUP CO LTD
- Filing Date
- 2026-01-15
- Publication Date
- 2026-04-10
AI Technical Summary
In OLED display panels, at low grayscale levels, variations in the manufacturing process can lead to different degrees of distortion and leakage in different light-emitting devices, resulting in inconsistent brightness and severe graininess in low grayscale images, leading to poor display quality.
By setting first and second hole transport layers with different horizontal sheet resistance in the display panel, the leakage degree of the first leakage path is enhanced and the leakage degree of the second leakage path is reduced, ensuring that the light emission brightness in each pixel opening is consistent, reducing the graininess of low grayscale images and avoiding color shift.
It achieves improved low grayscale display effect, reduces image graininess and avoids color deviation, improves luminous efficiency and reduces power consumption.
Smart Images
Figure CN121843375A_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The present application relates to the technical field of display, in particular to a display panel and a display device. BACKGROUND
[0002] An organic light emitting diode (OLED) is a current type organic light emitting device, and an OLED display panel is widely used in the display field due to its small thickness, self-luminous, high resolution, fast response speed and other advantages.
[0003] The OLED display panel generally comprises a driving back plate and a plurality of light emitting devices on the driving back plate, and the light emitting device comprises a first electrode layer, an organic light emitting layer and a second electrode layer which are stacked in a direction away from the driving back plate. A pixel definition layer is arranged between adjacent light emitting devices, and the pixel definition layer is provided with a partition groove on the side close to the light emitting device, which can block the horizontal leakage current. However, the part of the organic light emitting layer close to the partition groove will emit light due to distortion leakage, and by adjusting the morphology and height of the partition groove, the risk of distortion leakage can be reduced.
[0004] However, due to process deviation, the morphology or height of the partition groove corresponding to different light emitting devices is different, so that the light emitting intensity of the distorted part of the organic light emitting layer in different light emitting devices is different at low gray scale, resulting in a difference in light emitting brightness of different light emitting devices at low gray scale, causing serious low gray scale graininess and poor low gray scale display effect. SUMMARY
[0005] The present application provides a display panel and a display device, which can solve the problem of poor low gray scale display effect of the display panel. The technical solution is as follows: In one aspect, a display panel is provided, comprising a driving back plate, a first electrode layer, a pixel definition layer, an organic light emitting layer and a second electrode layer. The first electrode layer is located on one side of the driving back plate, and the first electrode layer has a plurality of separated first electrodes which are electrically connected with the driving back plate. The pixel definition layer is located on the side of the first electrode layer away from the driving back plate, and the pixel definition layer has a plurality of pixel openings and a partition groove distributed around the pixel openings. The organic light-emitting layer is located on the side of the pixel definition layer opposite to the driving backplane. The organic light-emitting layer includes: a first light-emitting functional layer, a charge generation layer and a second light-emitting functional layer stacked together; the first light-emitting functional layer includes: a first hole transport layer and a first light-emitting body layer stacked together in a direction away from the driving backplane; the second light-emitting functional layer includes: a second hole transport layer and a second light-emitting body layer stacked together in a direction away from the driving backplane. The second electrode layer is located on the side of the organic light-emitting layer opposite to the driving backplate; Wherein, the lateral sheet resistance of the first hole transport layer is less than that of the second hole transport layer, and the blocking groove is used to block at least the charge generation layer.
[0006] Optionally, the hole mobility of the first hole transport layer is greater than that of the second hole transport layer.
[0007] Optionally, the first light-emitting body layer is configured to emit yellow light, and the second light-emitting body layer is configured to emit blue light.
[0008] Optionally, the first light-emitting functional layer is closer to the driving backplate than the second light-emitting functional layer; the first light-emitting functional layer further includes a first electron transport layer, which is located on the side of the first light-emitting body layer away from the driving backplate, and the thickness of the first electron transport layer is less than the thickness of the second hole transport layer. Alternatively, the second light-emitting functional layer is closer to the driving backplate than the first light-emitting functional layer; the second light-emitting functional layer further includes a second electron transport layer, which is located on the side of the second light-emitting body layer away from the driving backplate, and the thickness of the second electron transport layer is less than the thickness of the first hole transport layer.
[0009] Optionally, the hole mobility of the first hole transport layer is 1*102 -5 square centimeters per volt-second ~ 1*10 -3 square centimeters per second, lateral sheet resistance is 10 1 gigaohms / square micrometer ~10 3 gigahertz ohms / square micrometer; the hole mobility of the second hole transport layer is 1*10 -6 square centimeters per volt-second ~ 1*10 -5 square centimeters per second, lateral sheet resistance is 10 4 gigaohms / square micrometer ~10 6 gigaohms per square micrometer.
[0010] Optionally, the pixel definition layer covers the edge portion of the first electrode, and the pixel definition layer includes: a first definition layer, a second definition layer, and a third definition layer stacked in a direction away from the driving backplate; the side of the first definition layer facing the pixel opening protrudes beyond the side of the second definition layer and the third definition layer facing the pixel opening, and the side of the third definition layer facing the pixel opening protrudes beyond the side of the second definition layer facing the pixel opening; The first definition layer, the second definition layer, and the third definition layer are used to form the partition groove.
[0011] Optionally, for the organic light-emitting layer located within the pixel opening and the pixel definition layer covering the edge portion of the first electrode, in a direction perpendicular to the driving backplate, the distance between the side of the charge-generating layer in the organic light-emitting layer facing away from the driving backplate and the first electrode is less than or equal to the distance between the side of the third definition layer in the pixel definition layer facing away from the driving backplate and the first electrode.
[0012] Optionally, the first light-emitting functional layer is closer to the driving backplate than the second light-emitting functional layer; for the organic light-emitting layer located within the pixel opening and the pixel definition layer covering the edge portion of the first electrode, in a direction perpendicular to the driving backplate, the distance between the side of the second hole transport layer in the organic light-emitting layer facing away from the driving backplate and the first electrode is greater than or equal to the distance between the side of the third definition layer in the pixel definition layer facing away from the driving backplate and the first electrode; Alternatively, the second light-emitting functional layer is closer to the driving backplate than the first light-emitting functional layer; for the organic light-emitting layer located within the pixel opening, and the pixel definition layer covering the edge portion of the first electrode, in a direction perpendicular to the driving backplate, the distance between the side of the first hole transport layer in the organic light-emitting layer facing away from the driving backplate and the driving backplate is greater than or equal to the distance between the side of the third definition layer in the pixel definition layer facing away from the driving backplate and the driving backplate.
[0013] Optionally, the portion of the first defining layer that protrudes from the second defining layer is a first protrusion; the portion of the first light-emitting body layer located on the side of the first protrusion away from the driving back plate is a first auxiliary light-emitting portion, and the portion of the second light-emitting body layer located on the side of the first protrusion away from the driving back plate is a second auxiliary light-emitting portion. When the display panel displays a low grayscale image, the brightness of the light emitted by the first auxiliary light-emitting part is greater than the brightness of the light emitted by the second auxiliary light-emitting part.
[0014] On the other hand, a display device is provided, comprising: a driver chip, and a display panel as described above, wherein the driver chip is electrically connected to the display panel.
[0015] The beneficial effects of the technical solution provided in this application include at least the following: The first hole transport layer has a lower lateral sheet resistance, which enhances the leakage of the first leakage path. Since the first leakage path passes through the distortion portion of the first light-emitting body layer, when the display panel shows a low grayscale image, the distortion portion of the first light-emitting body layer within each pixel opening can emit light, ensuring consistent brightness of the emitted light from each pixel opening, reducing graininess in low grayscale images, and improving the low grayscale display effect. Conversely, the second hole transport layer has a higher lateral sheet resistance, which reduces the leakage of the second leakage path. Since the second leakage path passes through the distortion portion of the second light-emitting body layer, when the display panel shows a low grayscale image, it reduces the probability of the distortion portion of the second light-emitting body layer emitting light, preventing color shift in low grayscale images. Attached Figure Description
[0016] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.
[0017] Figure 1 This is a schematic diagram of the film layer structure of a display panel provided by related technologies; Figure 2 This is a schematic diagram of the film layer structure of a display panel provided in an embodiment of this application; Figure 3 This is a schematic diagram of the film layer structure of a display panel provided in an embodiment of this application; Figure 4 This is a schematic diagram of the film layer structure of a display panel provided in an embodiment of this application; Figure 5 This is a schematic diagram of the film layer structure of a display panel provided in an embodiment of this application; Figure 6 This is a schematic diagram of the film layer structure of a display panel provided in an embodiment of this application; Figure 7 This is a schematic diagram of the film layer structure of a display panel provided in an embodiment of this application. Detailed Implementation
[0018] To make the objectives, technical solutions, and advantages of this application clearer, the embodiments of this application will be described in further detail below with reference to the accompanying drawings.
[0019] Please refer to Figure 1 , Figure 1 This is a schematic diagram of the film layer structure of a display panel provided by related technologies. The display panel may include: a driving backplane 10, a first electrode layer 20, a pixel definition layer 30, an organic light-emitting layer 40, and a second electrode layer 50.
[0020] The first electrode layer 20 is located on one side of the drive backplate 10. The first electrode layer 20 has a plurality of separately disposed first electrodes 21, and the first electrodes 21 can be electrically connected to the drive backplate 10.
[0021] The pixel definition layer 30 is located on the side of the first electrode layer 20 opposite to the driving backplate 10. The pixel definition layer 30 may have multiple pixel openings U and partition slots O distributed around the pixel openings U.
[0022] The organic light-emitting layer 40 is located on the side of the pixel definition layer 30 away from the driving backplate 10, and at least a portion of the organic light-emitting layer 40 can be located within the pixel opening U and in direct contact with the first electrode 21.
[0023] The organic light-emitting layer 40 may include: a first light-emitting functional layer 41, a charge-generating layer 43, and a second light-emitting functional layer 42 stacked together, wherein the charge-generating layer 43 is used to connect the first light-emitting functional layer 41 and the second light-emitting functional layer 42 in series. The first light-emitting functional layer 41 may include a first light-emitting body layer for emitting yellow light, and the second light-emitting functional layer 42 may include a second light-emitting body layer for emitting blue light.
[0024] The second electrode layer 50 is located on the side of the organic light-emitting layer 40 away from the driving backplate 100 and is in direct contact with the organic light-emitting layer 40.
[0025] It should be noted that the isolation slot O can at least be used to isolate the charge generation layer 43, thereby avoiding the lateral transmission of lateral leakage current in the charge generation layer 43 and causing pixel crosstalk. However, at the same time, the setting of the isolation slot O will cause distortion of the first light-emitting body layer and the second light-emitting body layer at the corresponding positions. The distorted part has a lower internal resistance, and the current will preferentially pass through the part with lower internal resistance. Therefore, the distorted part may have leakage problems.
[0026] Related technologies can reduce the distortion degree of the portion of the organic light-emitting layer 40 near the partition groove O by adjusting the morphology and height of the partition groove O, thereby reducing the risk of distortion leakage. For example... Figure 1As shown, if the leakage degree of the first leakage path L1 and the second leakage path L2 is small, then the distorted part in the first light-emitting body layer and the distorted part in the second light-emitting body layer can emit weak light or not emit light at all.
[0027] However, due to process variations, it is impossible to guarantee that the morphology and height of each partition groove O are completely identical, which will result in different degrees of distortion of the organic light-emitting layer 40 at different partition groove O.
[0028] When the display panel displays a low grayscale image, the parts of the organic light-emitting layer 40 with a higher degree of distortion have severe leakage current and emit strong light, while the parts with a lower degree of distortion have less leakage current and emit weak light or no light. Thus, the brightness of the light emitted from the pixel opening U with severe distortion and leakage current is higher, while the brightness of the light emitted from the pixel opening U with less distortion and leakage current is lower.
[0029] As a result, the brightness of light emitted from the aperture U of different pixels varies at low grayscale levels. Macroscopically, low grayscale images will exhibit a more severe graininess, resulting in poor low grayscale display effects.
[0030] Please refer to Figure 2 , Figure 2 This is a schematic diagram of the film layer structure of a display panel provided in an embodiment of this application. The display panel 000 may include: a driving backplate 100, a first electrode layer 200, a pixel definition layer 300, an organic light-emitting layer 400, and a second electrode layer 500.
[0031] The driving backplane 100 can be a silicon-based backplane; or, the driving backplane 100 can also be a glass-based backplane, that is, the substrate in the driving backplane 100 is glass. This application does not limit this.
[0032] The first electrode layer 200 may be located on one side of the drive backplate 100. The first electrode layer 200 has a plurality of separately disposed first electrodes 210, and the first electrodes 210 may be electrically connected to the drive backplate 100, so that the drive backplate 100 can apply voltage to the first electrodes 210.
[0033] The pixel definition layer 300 may be located on the side of the first electrode layer 200 opposite to the driving backplate 100. The pixel definition layer 300 may have multiple pixel openings U and partition grooves O distributed around the pixel openings U. In a direction perpendicular to the driving backplate 100, the pixel openings U may penetrate the pixel definition layer 300.
[0034] The organic light-emitting layer 400 can be located on the side of the pixel definition layer 300 away from the driving backplate 100, and at least a portion of the organic light-emitting layer 400 can be located within the pixel opening U and in direct contact with the first electrode 210.
[0035] The organic light-emitting layer 400 may include: a first light-emitting functional layer 410, a charge-generating layer 430, and a second light-emitting functional layer 420 stacked together, wherein the charge-generating layer 430 is used to connect the first light-emitting functional layer 410 and the second light-emitting functional layer 420 in series. The first light-emitting functional layer 410 may include: a first hole transport layer 411 and a first light-emitting body layer 412 stacked together in a direction away from the driving backplate 100, and the second light-emitting functional layer 420 may include: a second hole transport layer 421 and a second light-emitting body layer 422 stacked together in a direction away from the driving backplate 100.
[0036] The first hole transport layer 411 is used to transport holes to the first light-emitting body layer 412, and the second hole transport layer 421 is used to transport holes to the second light-emitting body layer 422. Holes and electrons recombine inside the first light-emitting body layer 412 and the second light-emitting body layer 422 and release energy in the form of photons, thereby enabling the first light-emitting body layer 412 and the second light-emitting body layer 422 to emit light.
[0037] The second electrode layer 500 can be located on the side of the organic light-emitting layer 400 away from the driving backplate 100 and can be in direct contact with the organic light-emitting layer 400.
[0038] The first electrode layer 200 can be an anode, and the second electrode layer 500 can be a cathode. When a corresponding voltage is applied to the first electrode layer 200 and the second electrode layer 500 respectively, an electric field is formed between the first electrode layer 200 and the second electrode layer 500. In this way, electrons and holes recombine and emit light in the first light-emitting body layer 412 and the second light-emitting body layer 422, thereby enabling the organic light-emitting layer 400 to emit light, and the display panel 000 can display an image.
[0039] It should be noted that the isolation slot O can at least be used to isolate the charge generation layer 430, thereby avoiding the lateral transmission of lateral leakage current in the charge generation layer 430 and causing pixel crosstalk.
[0040] It should also be noted that the first light-emitting body layer 412 and the second light-emitting body layer 422 are usually used to emit light of different colors, and the internal resistance of the first light-emitting body layer 412 is smaller than that of the second light-emitting body layer 422. That is, when a voltage is applied to the first electrode layer 200 and the second electrode layer 500, the first light-emitting body layer 412 will light up before the second light-emitting body layer 422.
[0041] When the display panel 000 displays a low grayscale image, the electric field between the first electrode layer 200 and the second electrode layer 500 is weak, so the first light-emitting body layer 412 is turned on, and the image color is more inclined to the color of the light emitted from the first light-emitting body layer 412.
[0042] It should also be noted that the portions of the first light-emitting body layer 412 and the second light-emitting body layer 422 near the partition groove O will experience a certain degree of distortion and leakage. Furthermore, due to process variations, it is impossible to guarantee that the morphology and height of each partition groove O are completely identical. This will result in different degrees of distortion and leakage in the first light-emitting body layer 412 and the second light-emitting body layer 422 at different partition groove Os. Consequently, at low grayscale, the luminous intensity of different distorted portions will also differ.
[0043] In the embodiments of this application, such as Figure 2 As shown, the lateral sheet resistance of the first hole transport layer 411 is made smaller than that of the second hole transport layer 421.
[0044] Thus, the lateral sheet resistance of the first hole transport layer 411 is relatively small, which enhances the leakage of the first leakage path L1 through the first hole transport layer 411. Since the first leakage path L1 passes through the distorted portion of the first light-emitting body layer 412, when the display panel 000 displays a low grayscale image, the distorted portion of the first light-emitting body layer 412 within each pixel opening U can emit light, thereby overcoming the problem of different light intensity of the distorted portion caused by process limitations, ensuring that the brightness of the light emitted from each pixel opening U is consistent, and thus reducing the graininess of the low grayscale image.
[0045] Furthermore, the second hole transport layer 421 has a larger lateral sheet resistance, which reduces the leakage of the second leakage path L2 through it. The second leakage path L2 passes through the distorted portion of the second light-emitting body layer 422. Therefore, when the display panel 000 displays a low grayscale image, the probability of the distorted portion of the second light-emitting body layer 422 emitting light is reduced. This ensures that the low grayscale image is biased towards the color of the light emitted from the first light-emitting body layer 412, avoiding color shift.
[0046] In summary, this application provides a display panel. The first hole transport layer has a low lateral sheet resistance, which enhances the leakage of the first leakage path through it. Since the first leakage path passes through the distortion portion of the first light-emitting body layer, when the display panel displays a low grayscale image, the distortion portion of the first light-emitting body layer within each pixel opening can emit light, thereby ensuring consistent brightness of the emitted light within each pixel opening, reducing graininess in low grayscale images, and improving the low grayscale display effect. Furthermore, the second hole transport layer has a high lateral sheet resistance, which reduces the leakage of the second leakage path through it. Since the second leakage path passes through the distortion portion of the second light-emitting body layer, when the display panel displays a low grayscale image, it reduces the probability of the distortion portion of the second light-emitting body layer emitting light, preventing color shift in the low grayscale image.
[0047] In this embodiment of the application, the hole mobility of the first hole transport layer 411 is greater than that of the second hole transport layer 421.
[0048] Thus, the hole mobility of the first hole transport layer 411 is relatively large, the hole movement speed in the first hole transport layer 411 is relatively fast, the hole transport efficiency is relatively high, thereby improving the luminous efficiency of the device.
[0049] Here, hole mobility refers to the hole mobility of the thin film in the longitudinal direction. It should be noted that the hole mobility in the transverse direction is related to the transverse sheet resistance of the thin film; the lower the transverse sheet resistance, the greater the hole mobility in the transverse direction. Conversely, a greater hole mobility in the transverse direction generally also results in a greater hole mobility in the longitudinal direction.
[0050] In this embodiment, the hole mobility of the first hole transport layer 411 can be 1*102 -5 square centimeters per volt-second ~ 1*10 -3 square centimeters per second, lateral sheet resistance can be 10. 1 gigaohms / square micrometer ~10 3 gigahertz ohms / square micrometer; the hole mobility of the second hole transport layer 421 can be 1*10^6 ohms / square micrometer. -6 square centimeters per volt-second ~ 1*10 -5 square centimeters per second, lateral sheet resistance can be 10. 4 gigaohms / square micrometer ~10 6 gigaohms per square micrometer.
[0051] For example, the hole mobility of the first hole transport layer 411 can be 3.2*10^6. -4 Square centimeters per second, lateral sheet resistance can be 80 gigahertz ohms per square micrometer; the hole mobility of the second hole transport layer 421 can be 5*10 -6 Square centimeters per second, lateral sheet resistance can be 3.2*10 4 gigaohms per square micrometer.
[0052] However, in related technologies, the first and second hole transport layers are made of the same material, and the hole mobility of both the first and second hole transport layers can be 5*10. -6 Square centimeters per second, and lateral sheet resistance can both be 3.2*10. 4 gigaohms per square micrometer.
[0053] Therefore, compared with related technologies, the first hole transport layer 411 in this embodiment has a smaller lateral sheet resistance and a larger hole mobility.
[0054] In this way, the leakage of the first leakage path L1 through the first hole transport layer 411 can be enhanced, and the distorted part of the first light-emitting body layer 412 in each pixel opening U can emit light at low grayscale, so the brightness of the light emitted from each pixel opening U is consistent, and the graininess of the low grayscale image can be reduced.
[0055] Furthermore, in related technologies, the hole mobility of both the first and second hole transport layers is relatively low, resulting in low hole transport efficiency. Consequently, the display panels in these technologies require higher driving voltages. However, in this embodiment, the hole mobility of the first hole transport layer 411 is relatively high, which improves hole transport efficiency, increases the luminous efficiency of the device, and reduces driving voltage and power consumption.
[0056] In one possible implementation, the first light-emitting body layer 412 can be configured to emit yellow light, and the second light-emitting body layer 422 can be configured to emit blue light.
[0057] The first light-emitting body layer 412 may include a red sub-light-emitting body layer and a green sub-light-emitting body layer stacked together. The red sub-light-emitting body layer is configured to emit red light, and the green sub-light-emitting body layer is configured to emit green light. After the red light and green light are mixed, the first light-emitting body layer 412 can be used to emit yellow light.
[0058] Since the internal resistance of the first light-emitting body layer 412 is smaller than that of the second light-emitting body layer 422, when the display panel 000 displays a low grayscale image, the first light-emitting body layer 412 will be turned on before the second light-emitting body layer 422, so the low grayscale image can appear yellow-green.
[0059] It should be noted that the positions of the first light-emitting functional layer 410 and the second light-emitting functional layer 420 in the organic light-emitting layer 400 can be interchanged, and this application embodiment does not limit this.
[0060] In one exemplary implementation, such as Figure 2 As shown, the first light-emitting functional layer 410 can be closer to the driving backplate 100 than the second light-emitting functional layer 420.
[0061] The first light-emitting functional layer 410 may further include a first electron transport layer 413. The first electron transport layer 413 may be located on the side of the first light-emitting body layer 412 away from the driving backplate 100, and the first electron transport layer 413 is used to transport electrons to the first light-emitting body layer 412.
[0062] The thickness of the first electron transport layer 413 can be less than the thickness of the second hole transport layer 421.
[0063] In this way, the thickness of the first electron transport layer 413 is small, and the distance between the charge generation layer 430 located in the pixel opening U and the first electrode 210 on the side facing away from the driving back plate 100 is small, thereby ensuring that the first light-emitting functional layer 410 and the charge generation layer 430 can be completely isolated by the isolation groove O, so as to avoid the lateral leakage current in the charge generation layer 430 causing pixel crosstalk.
[0064] In addition, since the second hole transport layer 421 is in direct contact with the charge generation layer 430, the charge generation layer 430 is completely isolated by the isolation groove O, which can also reduce the leakage degree of the second leakage path L2 to a certain extent, and further prevent the distorted part of the second light-emitting body layer 422 from emitting blue light under low grayscale.
[0065] In one possible scenario, the thickness values of each film layer in the organic light-emitting layer of the related technology are shown in Table 1, and the thickness values of each film layer in the organic light-emitting layer 400 of the present application embodiment are shown in Table 2.
[0066] In related technologies, the thickness of the first electron transport layer is 210 angstroms and the thickness of the second hole transport layer is 190 angstroms. However, in the embodiments of this application, the thickness of the first electron transport layer 413 is 110 angstroms and the thickness of the second hole transport layer 421 is 290 angstroms.
[0067] In this way, the thickness of the first electron transport layer 413 can be less than the thickness of the second hole transport layer 421. Furthermore, it can be ensured that the sum of the thicknesses of the first electron transport layer 413 and the second hole transport layer 421 remains unchanged, so the thickness of the organic light-emitting layer 400 can remain constant at 2100 angstroms. That is, the distance between the first electrode 210 and the second electrode layer 500 remains unchanged, and thus the microcavity length remains unchanged.
[0068] Table 1
[0069] Table 2
[0070] In another exemplary implementation, such as Figure 3 As shown, the second light-emitting functional layer 420 can be closer to the driving backplate 100 than the first light-emitting functional layer 410.
[0071] The second light-emitting functional layer 420 may further include a second electron transport layer 423. The second electron transport layer 423 may be located on the side of the second light-emitting body layer 422 away from the driving backplate 100, and the second electron transport layer 423 is used to transport electrons to the second light-emitting body layer 422.
[0072] The thickness of the second electron transport layer 423 can be less than the thickness of the first hole transport layer 411.
[0073] In this way, the thickness of the second electron transport layer 423 is smaller, and the distance between the charge generation layer 430 located in the pixel opening U and the first electrode 210 on the side facing away from the driving back plate 100 is smaller, thereby ensuring that the second light-emitting functional layer 420 and the charge generation layer 430 can be completely isolated by the isolation groove O, so as to avoid the lateral leakage current in the charge generation layer 430 causing pixel crosstalk.
[0074] See Figure 2 and Figure 3 The pixel definition layer 300 can cover the edge portion of the first electrode 210, which can prevent the edge of the first electrode 210 from causing sharp leakage.
[0075] See also Figure 2 and Figure 3 The pixel definition layer 300 may include a first definition layer 310, a second definition layer 320 and a third definition layer 330 stacked in a direction away from the driving backplate 100, with the pixel opening U passing through the first definition layer 310, the second definition layer 320 and the third definition layer 330 in sequence.
[0076] The first defining layer 310 can protrude beyond the second defining layer 320 and the third defining layer 330 facing the pixel opening U, and the third defining layer 330 can protrude beyond the second defining layer 320 facing the pixel opening U. Therefore, the first defining layer 310, the second defining layer 320, and the third defining layer 330 can be used to form a barrier groove O to isolate the charge generating layer 430.
[0077] It should be noted that, for the organic light-emitting layer 400 located within the pixel opening U, and the pixel definition layer 300 covering the edge portion of the first electrode 210, in the direction perpendicular to the driving backplate 100, the distance between the side of the charge generation layer 430 in the organic light-emitting layer 400 facing away from the driving backplate 100 and the first electrode 210 can be less than or equal to the distance between the side of the third definition layer 330 in the pixel definition layer 300 facing away from the driving backplate 100 and the first electrode 210.
[0078] For example, if the thickness of the first defining layer 310 is 200 angstroms, the thickness of the second defining layer 320 is 500 angstroms, and the thickness of the third defining layer 330 is 300 angstroms, then the distance between the side of the third defining layer 330 facing away from the driving backplate 100 and the first electrode 210 is 1000 angstroms. As shown in Table 2, for a display panel 000 where the first light-emitting functional layer 410 is closer to the driving backplate 100, the thickness of the first light-emitting functional layer 410 of the organic light-emitting layer 400 in the display panel 000 is 770 angstroms, and the thickness of the charge-generating layer 430 is 185 angstroms. Then the distance between the side of the charge-generating layer 430 of the organic light-emitting layer 400 facing away from the driving backplate 100 and the first electrode 210 in the pixel opening U can be 955 angstroms.
[0079] In this way, the isolation slot O can isolate the charge generation layer 430, thereby preventing the lateral leakage current in the charge generation layer 430 from being transmitted to adjacent pixels and causing pixel crosstalk, thus ensuring that the display panel 000 has a good display effect.
[0080] In one exemplary implementation, such as Figure 2 As shown, the first light-emitting functional layer 410 can be closer to the driving backplate 100 than the second light-emitting functional layer 420.
[0081] For the organic light-emitting layer 400 located within the pixel opening U, and the pixel definition layer 300 covering the edge portion of the first electrode 210, in the direction perpendicular to the driving backplate 100, the distance between the side of the second hole transport layer 421 in the organic light-emitting layer 400 facing away from the driving backplate 100 and the first electrode 210 can be greater than or equal to the distance between the side of the third definition layer 330 in the pixel definition layer 300 facing away from the driving backplate 100 and the first electrode 210.
[0082] For example, the distance between the third defining layer 330, which is away from the driving backplate 100, and the first electrode 210 is 1000 angstroms. As shown in Table 2, the distance between the second hole transport layer 421 of the organic light-emitting layer 400, which is located in the pixel opening U, and the first electrode 210, which is away from the driving backplate 100, can be 1245 angstroms.
[0083] In this way, the second electrode layer 500 can be prevented from being isolated, thereby avoiding open circuits in the second electrode layer 500 and ensuring the normal operation of the display panel 000.
[0084] In addition, the second light-emitting body layer 422 can also avoid being blocked, which can reduce the degree of distortion of the second light-emitting body layer 422 at the blocking groove O to a certain extent, thereby preventing the distorted part of the second light-emitting body layer 422 from leaking and emitting blue light at low gray levels.
[0085] In another exemplary implementation, such as Figure 3As shown, the second light-emitting functional layer 420 can be closer to the driving backplate 100 than the first light-emitting functional layer 410.
[0086] For the organic light-emitting layer 400 located within the pixel opening U, and the pixel definition layer 300 covering the edge portion of the first electrode 210, in the direction perpendicular to the driving backplate 100, the distance between the side of the first hole transport layer 411 in the organic light-emitting layer 400 facing away from the driving backplate 100 and the first electrode 210 can be greater than or equal to the distance between the side of the third definition layer 330 in the pixel definition layer 300 facing away from the driving backplate 100 and the first electrode 210.
[0087] In this way, the second electrode layer 500 and the first light-emitting body layer 412 in the first light-emitting functional layer 410 can be prevented from being isolated, and an open circuit in the second electrode layer 500 can be avoided, thereby ensuring the normal driving of the display panel 000.
[0088] It should be noted that, see Figure 2 and Figure 3 The portion of the first defining layer 310 that protrudes from the second defining layer 320 is the first protrusion T1.
[0089] The portion of the first light-emitting body layer 412 located on the side of the first protrusion T1 facing away from the driving backplate 100 is the first auxiliary light-emitting part F1, and the portion of the second light-emitting body layer 422 located on the side of the first protrusion T1 facing away from the driving backplate 100 is the second auxiliary light-emitting part F2. That is, the first auxiliary light-emitting part F1 is the distorted portion of the first light-emitting body layer 412, and the second auxiliary light-emitting part F2 is the distorted portion of the second light-emitting body layer 422.
[0090] In related technologies, if both the first leakage path and the second leakage path are weak, the distorted portions in the first and second light-emitting body layers will emit light weakly or not at all.
[0091] However, in this embodiment, the leakage level of the first leakage path L1 through the first hole transmission layer 411 is enhanced. Therefore, when the display panel 000 displays a low grayscale image, the brightness of the light emitted by the first auxiliary light-emitting part F1 can be greater than the brightness of the light emitted by the second auxiliary light-emitting part F2.
[0092] Thus, at low grayscale, the first auxiliary light-emitting part F1 at each of the first protrusions T1 can emit light, thereby making the brightness of the light emitted from each pixel opening U consistent, and thus reducing the graininess of the low grayscale image. Furthermore, the second auxiliary light-emitting part F2 has a lower light intensity, thereby preventing color shift in the low grayscale image.
[0093] like Figure 4 and Figure 5As shown, the display panel 000 may also include an encapsulation layer 600, which may be located on the side of the second electrode layer 500 away from the driving backplate 100.
[0094] In one possible scenario, the encapsulation layer 600 may include a first inorganic encapsulation layer 610, an organic encapsulation layer 620, and a second inorganic encapsulation layer 630 stacked together.
[0095] The encapsulation layer 600 can encapsulate and protect the organic light-emitting layer 400 and the second electrode layer 500 to prevent water and oxygen corrosion from the external environment. At the same time, the organic encapsulation layer 620 in the encapsulation layer 600 can also play a certain role in planarization of the film layers.
[0096] See also Figure 4 and Figure 5 The display panel 000 may also include a color filter layer 700, which may be located on the side of the encapsulation layer 600 away from the driving backplate 100.
[0097] The color filter layer 700 may include multiple color resist blocks, which may correspond to multiple pixel openings U. The orthographic projection of the pixel opening U on the driving backplane 100 lies within the orthographic projection of the corresponding color resist block on the driving backplane 100. The multiple color resist blocks may include multiple red color resist blocks, multiple green color resist blocks, and multiple blue color resist blocks. The color resist blocks can select and filter light.
[0098] Since the first light-emitting body layer 412 in the first light-emitting functional layer 410 is used to emit yellow light, and the second light-emitting body layer 422 in the second light-emitting functional layer 420 is used to emit blue light, the organic light-emitting layer 400 can emit white light after mixing. White light can be filtered by a red color block to emit red light, filtered by a green color block to emit green light, and filtered by a blue color block to emit blue light. Therefore, the mixing and superposition of different colors of light can enable the display panel 000 to display the corresponding image.
[0099] It should be noted that the organic light-emitting layer 400 may further include an electron injection layer and a hole injection layer. The hole injection layer can be in direct contact with the first electrode layer 200, so the first electrode layer 200 can inject holes into the hole injection layer; the electron injection layer can be in direct contact with the second electrode layer 500, so the second electrode layer 500 can inject electrons into the electron injection layer.
[0100] It should also be noted that the first light-emitting functional layer 410 may further include a first hole-blocking layer, which may be located between the first light-emitting body layer 412 and the first electron transport layer 413 to prevent holes from continuing to travel to the first electron transport layer 413, thereby allowing holes and electrons to recombine within the first light-emitting body layer 412. The second light-emitting functional layer 420 may further include a second hole-blocking layer, which may be located between the second light-emitting body layer 422 and the second electron transport layer 423 to prevent holes from continuing to travel to the second electron transport layer 423, thereby allowing holes and electrons to recombine within the second light-emitting body layer 422.
[0101] It should also be noted that the display panel 000 may include: a strong microcavity display panel and a weak microcavity display panel. Compared to the weak microcavity structure, the microcavity effect of the strong microcavity structure can effectively increase the intensity of emitted light and improve device efficiency.
[0102] like Figure 6 As shown, when the display panel 000 has a weak microcavity structure, the first electrode 210 may include a reflective anode 211 and a transparent anode 212 stacked together, with the reflective anode 211 being closer to the driving backplate 100 than the transparent anode 212; the second electrode layer 500 may be a transparent cathode. The transparent anode 212 may be made of indium tin oxide.
[0103] like Figure 7 As shown, when the display panel 000 has a strong microcavity structure, the first electrode 210 may include: a reflective anode 211, a microcavity adjustment part 213, and a transparent anode 212 stacked together, with the reflective anode 211 being closer to the drive backplate 100 than the transparent anode 212; the second electrode layer 500 may be a semi-transparent, semi-reflective cathode. The transparent anode 212 may be made of indium tin oxide.
[0104] A resonant cavity can be formed between the reflective anode 211 and the semi-transparent semi-reflective cathode, and the intensity of the emitted light can be enhanced through the strong microcavity resonance effect.
[0105] The microcavity adjustment section 213 can be transparent and can be used to adjust the length of the microcavity so that the microcavity is adapted to the wavelength of the emitted light.
[0106] For a red sub-pixel R emitting red light, a green sub-pixel G emitting green light, and a blue sub-pixel B emitting blue light, in one possible scenario, the thickness of the microcavity adjustment portion 213 in the red sub-pixel R is greater than the thickness of the microcavity adjustment portion 213 in the green sub-pixel G, and the thickness of the microcavity adjustment portion 213 in the green sub-pixel G is greater than the thickness of the microcavity adjustment portion 213 in the blue sub-pixel B; in other possible scenarios, the thickness of the microcavity adjustment portion 213 in the blue sub-pixel B is greater than the thickness of the microcavity adjustment portion 213 in the red sub-pixel R, and the thickness of the microcavity adjustment portion 213 in the red sub-pixel R is greater than the thickness of the microcavity adjustment portion 213 in the green sub-pixel G. This application does not limit this aspect.
[0107] The microcavity adjustment section 213 can be a conductive film layer or an insulating film layer, and this embodiment does not limit this. When the microcavity adjustment section 213 is a conductive film layer, the reflective anode 211 and the transparent anode 212 can be electrically connected through the microcavity adjustment section 213; when the microcavity adjustment section 213 is an insulating film layer, the reflective anode 211 and the transparent anode 212 can be electrically connected through the vias in the microcavity adjustment section 213.
[0108] It should be noted that, according to the applicant's experimental measurements, the display panel 000 provided in this application embodiment has improved device efficiency and lifespan compared to display panels in related technologies. For example, device efficiency is improved by 2%, lifespan is improved by 12%, and the required driving voltage is reduced by 4%.
[0109] It should also be noted that, in this embodiment of the application, the manufacturing process of the display panel 000 is as follows: Step S101: Provide a drive backplane.
[0110] like Figure 4 As shown, the driving backplane 100 can be a silicon-based backplane or a glass-based backplane, and this application embodiment does not limit this.
[0111] Step S102: Form a first electrode layer on one side of the drive backplate.
[0112] like Figure 4 As shown, a first electrode layer 200 is formed on one side of the drive backplate 100. The first electrode layer 200 has a plurality of separately disposed first electrodes 210, and the first electrodes 210 can be electrically connected to the drive backplate 100, so that the drive backplate 100 can apply voltage to the first electrodes 210.
[0113] The material and thickness of the first electrode layer 200 can be selected from various options, and this application embodiment does not limit them.
[0114] For example, the first electrode layer 200 may include: an indium tin oxide film, a silver film and an indium tin oxide film stacked together, wherein the thickness of the two indium tin oxide films can be 80 angstroms and the thickness of the silver film can be 1000 angstroms.
[0115] As another example, the first electrode layer 200 may include: a stacked titanium film, an aluminum film, a titanium film, and an indium tin oxide film; or, the first electrode layer 200 may include: a stacked titanium film, an aluminum film, a titanium nitride film, and an indium tin oxide film. The thickness of the titanium film and the titanium nitride film may be 50 angstroms to 100 angstroms, the thickness of the aluminum film may be 800 angstroms to 2000 angstroms, and the thickness of the indium tin oxide film may be 50 angstroms to 100 angstroms.
[0116] Step S103: A pixel definition layer is formed on the side of the first electrode layer away from the driving backplate.
[0117] like Figure 4 As shown, a pixel definition layer 300 is formed on the side of the first electrode layer 200 opposite to the driving backplate 100. The pixel definition layer 300 may have multiple pixel openings U and partition slots O distributed around the pixel openings U.
[0118] The pixel definition layer 300 may include a first definition layer 310, a second definition layer 320, and a third definition layer 330 stacked along a direction away from the driving backplate 100. The side of the first definition layer 310 facing the pixel opening U may protrude beyond the sides of the second definition layer 320 and the third definition layer 330 facing the pixel opening U, and the side of the third definition layer 330 facing the pixel opening U may protrude beyond the side of the second definition layer 320 facing the pixel opening U. Therefore, the first definition layer 310, the second definition layer 320, and the third definition layer 330 can be used to form a barrier groove O to isolate the charge generation layer 430.
[0119] The first defining layer 310 and the third defining layer 330 can both be made of silicon oxide material, and the thickness of the first defining layer 310 and the third defining layer 330 can both be 50 angstroms to 500 angstroms; the second defining layer 320 can be made of silicon nitride material, and the thickness of the second defining layer 320 can be 300 angstroms to 1000 angstroms.
[0120] Step S104: An organic light-emitting layer is formed on the side of the pixel definition layer away from the driving backplane.
[0121] like Figure 4 As shown, an organic light-emitting layer 400 is formed on the side of the pixel definition layer 300 opposite to the driving backplate 100.
[0122] The organic light-emitting layer 400 may include: a first light-emitting functional layer 410, a charge-generating layer 430, and a second light-emitting functional layer 420 stacked together, wherein the charge-generating layer 430 is used to connect the first light-emitting functional layer 410 and the second light-emitting functional layer 420 in series. The first light-emitting functional layer 410 may include: a first hole transport layer 411 and a first light-emitting body layer 412 stacked together in a direction away from the driving backplate 100, and the second light-emitting functional layer 420 may include: a second hole transport layer 421 and a second light-emitting body layer 422 stacked together in a direction away from the driving backplate 100.
[0123] The first hole transport layer 411 has a smaller lateral sheet resistance than the second hole transport layer 421, and the hole mobility of the first hole transport layer 411 is greater than that of the second hole transport layer 421.
[0124] Step S105: Form a second electrode layer on the side of the organic light-emitting layer away from the driving backplate.
[0125] like Figure 4 As shown, a second electrode layer 500 is formed on the side of the organic light-emitting layer 400 opposite to the driving backplate 100.
[0126] In one possible scenario, the second electrode layer 500 can be prepared from indium zinc oxide, and the thickness of the second electrode layer 500 can be 1500 angstroms.
[0127] Step S106: Form an encapsulation layer on the side of the second electrode layer away from the drive backplate.
[0128] like Figure 4 As shown, an encapsulation layer 600 is formed on the side of the second electrode layer 500 opposite to the drive backplate 100.
[0129] Step S107: Form a color filter layer on the side of the encapsulation layer away from the drive backplane.
[0130] like Figure 4 Figure 4 As shown, a color filter layer 700 is formed on the side of the encapsulation layer 600 opposite to the drive backplane 100.
[0131] The specific structure and functions of the display panel 000 can be referred to in the above embodiments, and will not be repeated here.
[0132] In summary, this application provides a display panel. The first hole transport layer has a low lateral sheet resistance, which enhances the leakage of the first leakage path through it. Since the first leakage path passes through the distortion portion of the first light-emitting body layer, when the display panel displays a low grayscale image, the distortion portion of the first light-emitting body layer within each pixel opening can emit light, thereby ensuring consistent brightness of the emitted light within each pixel opening, reducing graininess in low grayscale images, and improving the low grayscale display effect. Furthermore, the second hole transport layer has a high lateral sheet resistance, which reduces the leakage of the second leakage path through it. Since the second leakage path passes through the distortion portion of the second light-emitting body layer, when the display panel displays a low grayscale image, it reduces the probability of the distortion portion of the second light-emitting body layer emitting light, preventing color shift in the low grayscale image.
[0133] This application also provides a display device, which can be any product or component with display function, such as AR (Augmented Reality), VR (Virtual Reality), mobile phone, tablet computer, television, monitor, laptop computer, digital photo frame, navigator, etc.
[0134] The display device may include a driver chip and a display panel. The display panel may be a micro-organic light-emitting diode (Micro-OLED) display panel, and may be the display panel 000 described in the above embodiments. The driver chip may be electrically connected to the display panel 000, thereby driving the display panel 000 to display an image.
[0135] It should be noted that the dimensions of layers and regions may be exaggerated in the accompanying drawings for clarity. Furthermore, it is understood that when an element or layer is referred to as being "on" another element or layer, it can be directly on the other element, or there may be intermediate layers. Additionally, it is understood that when an element or layer is referred to as being "below" another element or layer, it can be directly below the other element, or there may be more than one intermediate layer or element. Furthermore, it is also understood that when a layer or element is referred to as being "between" two layers or two elements, it can be the only layer between the two layers or two elements, or there may be more than one intermediate layer or element. Similar reference numerals throughout indicate similar elements.
[0136] In this application, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance. The term "multiple" refers to two or more unless otherwise expressly defined.
[0137] The above description is merely an optional embodiment of this application and is not intended to limit this application. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the protection scope of this application.
Claims
1. A display panel, characterized in that, include: Drive backplane, first electrode layer, pixel definition layer, organic light-emitting layer and second electrode layer; The first electrode layer is located on one side of the drive back plate, and the first electrode layer has a plurality of separately disposed first electrodes, which are electrically connected to the drive back plate. The pixel definition layer is located on the side of the first electrode layer away from the driving backplate. The pixel definition layer has multiple pixel openings and partition slots distributed around the pixel openings. The organic light-emitting layer is located on the side of the pixel definition layer opposite to the driving backplane. The organic light-emitting layer includes: a first light-emitting functional layer, a charge generation layer and a second light-emitting functional layer stacked together; the first light-emitting functional layer includes: a first hole transport layer and a first light-emitting body layer stacked together in a direction away from the driving backplane; the second light-emitting functional layer includes: a second hole transport layer and a second light-emitting body layer stacked together in a direction away from the driving backplane. The second electrode layer is located on the side of the organic light-emitting layer opposite to the driving backplate; Wherein, the lateral sheet resistance of the first hole transport layer is less than that of the second hole transport layer, and the blocking groove is used to block at least the charge generation layer.
2. The display panel according to claim 1, characterized in that, The hole mobility of the first hole transport layer is greater than that of the second hole transport layer.
3. The display panel according to claim 2, characterized in that, The first light-emitting body layer is configured to emit yellow light, and the second light-emitting body layer is configured to emit blue light.
4. The display panel according to claim 3, characterized in that, The first light-emitting functional layer is closer to the driving backplate than the second light-emitting functional layer; the first light-emitting functional layer also includes a first electron transport layer, which is located on the side of the first light-emitting body layer away from the driving backplate, and the thickness of the first electron transport layer is less than the thickness of the second hole transport layer. Alternatively, the second light-emitting functional layer is closer to the driving backplate than the first light-emitting functional layer; the second light-emitting functional layer further includes a second electron transport layer, which is located on the side of the second light-emitting body layer away from the driving backplate, and the thickness of the second electron transport layer is less than the thickness of the first hole transport layer.
5. The display panel according to any one of claims 2 to 4, characterized in that, The hole mobility of the first hole transport layer is 1*10 -5 square centimeters per volt-second ~ 1*10 -3 square centimeters per second, lateral sheet resistance is 10 1 gigaohms / square micrometer ~10 3 gigahertz ohms / square micrometer; the hole mobility of the second hole transport layer is 1*10 -6 square centimeters per volt-second ~ 1*10 -5 square centimeters per second, lateral sheet resistance is 10 4 gigaohms / square micrometer ~10 6 gigaohms per square micrometer.
6. The display panel according to any one of claims 1 to 4, characterized in that, The pixel definition layer covers the edge portion of the first electrode, and the pixel definition layer includes: a first definition layer, a second definition layer, and a third definition layer stacked in a direction away from the driving backplate; the side of the first definition layer facing the pixel opening protrudes from the side of the second definition layer and the side of the third definition layer facing the pixel opening, and the side of the third definition layer facing the pixel opening protrudes from the side of the second definition layer facing the pixel opening; The first definition layer, the second definition layer, and the third definition layer are used to form the partition groove.
7. The display panel according to claim 6, characterized in that, For the organic light-emitting layer located within the pixel opening and the pixel definition layer covering the edge portion of the first electrode, in a direction perpendicular to the driving backplate, the distance between the side of the charge-generating layer in the organic light-emitting layer facing away from the driving backplate and the first electrode is less than or equal to the distance between the side of the third definition layer in the pixel definition layer facing away from the driving backplate and the first electrode.
8. The display panel according to claim 7, characterized in that, The first light-emitting functional layer is closer to the driving backplate than the second light-emitting functional layer; for the organic light-emitting layer located in the pixel opening and the pixel definition layer covering the edge portion of the first electrode, in the direction perpendicular to the driving backplate, the distance between the side of the second hole transport layer in the organic light-emitting layer away from the driving backplate and the first electrode is greater than or equal to the distance between the side of the third definition layer in the pixel definition layer away from the driving backplate and the first electrode. Alternatively, the second light-emitting functional layer is closer to the driving backplate than the first light-emitting functional layer; for the organic light-emitting layer located within the pixel opening, and the pixel definition layer covering the edge portion of the first electrode, in a direction perpendicular to the driving backplate, the distance between the side of the first hole transport layer in the organic light-emitting layer facing away from the driving backplate and the driving backplate is greater than or equal to the distance between the side of the third definition layer in the pixel definition layer facing away from the driving backplate and the driving backplate.
9. The display panel according to claim 6, characterized in that, The portion of the first defining layer that protrudes from the second defining layer is the first protrusion; the portion of the first light-emitting body layer located on the side of the first protrusion away from the driving back plate is the first auxiliary light-emitting part; the portion of the second light-emitting body layer located on the side of the first protrusion away from the driving back plate is the second auxiliary light-emitting part. When the display panel displays a low grayscale image, the brightness of the light emitted by the first auxiliary light-emitting part is greater than the brightness of the light emitted by the second auxiliary light-emitting part.
10. A display device, characterized in that, include: The driver chip and the display panel according to any one of claims 1 to 9, wherein the driver chip is electrically connected to the display panel.