A display panel and display device

Abstract

The application discloses a display panel and a display device, the display panel comprising: a plurality of first pixel areas, a plurality of second pixel areas and a plurality of third pixel areas; the light-emitting colors of the first pixel areas, the second pixel areas and the third pixel areas are different; the display panel further comprises: a driving substrate; a plurality of light-emitting devices located on one side of the driving substrate; the light-emitting device comprises a first anode, a first light-emitting layer, a charge generation layer, a second light-emitting layer and a first cathode which are sequentially stacked; the charge generation layer generates electrons and holes under the action of an electric field; at least the light-emitting device located in the first pixel area is a first light-emitting device; the first light-emitting device further comprises a second cathode and a first charge blocking layer. The display panel disclosed by the application sets the second cathode and the first charge blocking layer in the first light-emitting device of the first pixel area, so that the light-emitting color of the first pixel area is the light-emitting color of the first light-emitting layer, the power consumption and heat of the display panel are reduced, and the service life of the display panel is prolonged.

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] At present, the structure adopted by the micro display industry is generally a white organic light emitting diode (OLED) and a color filter layer stack to realize color. Under this structure, the color filter layer filters out the remaining light color, so that it can emit different color single light. However, the transmittance of the general color filter layer is about 20%-30%, so the performance requirements of the white light device are relatively high.

[0003] In order to meet the demand of display module on the market, the requirement of white light is at least 1000nit, and the brightness of white OLED is at least greater than 3000nit. In order to meet the demand, the voltage will be increased, so that the product will generate a large power consumption and heat. SUMMARY

[0004] The present application provides a display panel and a display device to reduce the power consumption and heat of the display panel and prolong the service life of the display panel.

[0005] In a first aspect, the present application provides a display panel, comprising: a plurality of first pixel areas, a plurality of second pixel areas and a plurality of third pixel areas; the light emitting colors of the first pixel areas, the second pixel areas and the third pixel areas are different;

[0006] The display panel further comprises:

[0007] a driving substrate;

[0008] a plurality of light emitting devices located on one side of the driving substrate; the light emitting device comprises a first anode, a first light emitting layer, a charge generation layer, a second light emitting layer and a first cathode which are sequentially stacked; the charge generation layer generates electrons and holes under the action of an electric field; the first light emitting layer and the second light emitting layer generate different color light which is recombined to form white light;

[0009] The light emitting device located in the first pixel area is a first light emitting device; the first light emitting device further comprises a second cathode and a first charge blocking layer;

[0010] The second cathode is located between the charge generation layer and the first light-emitting layer in the first light-emitting device; the first charge blocking layer is located between the second cathode and the charge generation layer or between the second light-emitting layer and the charge generation layer; the first charge blocking layer prevents the holes from transmitting to the second light-emitting layer; and the first light-emitting layer of the first light-emitting device has the same light-emitting color as the light-emitting color of the first pixel region.

[0011] Optionally, the display panel further comprises:

[0012] A color filter layer is located on the side of the light-emitting device away from the driving substrate; the color filter layer comprises a first filter layer and a second filter layer located in the second pixel region and the third pixel region respectively, and the first pixel region is not provided with the color filter layer.

[0013] Optionally, the charge generation layer comprises a first semiconductor layer and a second semiconductor layer stacked; one of the first semiconductor layer and the second semiconductor layer is used for generating holes, and the other is used for generating electrons; the first charge blocking layer comprises a third semiconductor layer.

[0014] In the first light-emitting device, when the third semiconductor layer is located on the side of the first semiconductor layer away from the second semiconductor layer, the third semiconductor layer has the same doping type as the second semiconductor layer; or when the third semiconductor layer is located on the side of the second semiconductor layer away from the first semiconductor layer, the third semiconductor layer has the same doping type as the first semiconductor layer.

[0015] Optionally, in the first light-emitting device, the first semiconductor layer, the second semiconductor layer and the third semiconductor layer form an NPN structure or a PNP structure.

[0016] Optionally, the light-emitting device located in the second pixel region and / or the third pixel region is a second light-emitting device.

[0017] The second light-emitting device further comprises a third cathode; and in the second light-emitting device, the third cathode is located between the first light-emitting layer and the charge generation layer.

[0018] Optionally, the third cathode is provided in the same layer as the second cathode.

[0019] Optionally, the display panel further comprises:

[0020] The first cathode transmission line and the second cathode transmission line are insulated from each other; the first cathode transmission line is electrically connected to the first cathode of each light-emitting device; and the second cathode transmission line is electrically connected to the second cathode of the first light-emitting device and the third cathode of the second light-emitting device respectively.

[0021] The driving substrate comprises a plurality of driving circuits; each of the driving circuits is electrically connected with the first anode of each of the light emitting devices.

[0022] Optionally, the light emitting device located in the second pixel area is a second light emitting device; the second light emitting device further comprises a second anode and a second charge blocking layer.

[0023] In the same second light emitting device, the second anode is located between the charge generation layer and the second light emitting layer; the second charge blocking layer is located between the second anode and the charge generation layer or between the first light emitting layer and the charge generation layer; the second charge blocking layer prevents the electrons generated by the charge generation layer from transmitting to the first light emitting layer; wherein the light emitting color of the second light emitting layer of the second light emitting device is the same as the light emitting color of the second pixel area.

[0024] Optionally, further comprising:

[0025] A color filter layer is located on the side of the light emitting device away from the driving substrate; the color filter layer is located in the third pixel area, and the first pixel area and the second pixel area are not provided with the color filter layer.

[0026] Optionally, the charge generation layer comprises a first semiconductor layer and a second semiconductor layer which are stacked; one of the first semiconductor layer and the second semiconductor layer is used for generating holes, and the other is used for generating electrons; the second charge blocking layer comprises a fourth semiconductor layer.

[0027] In the same second light emitting device, when the fourth semiconductor layer is located on the side of the first semiconductor layer away from the second semiconductor layer, the fourth semiconductor layer and the second semiconductor layer have the same doping type; or when the fourth semiconductor layer is located on the side of the second semiconductor layer away from the first semiconductor layer, the fourth semiconductor layer and the first semiconductor layer have the same doping type.

[0028] Optionally, in the same second light emitting device, the first semiconductor layer, the second semiconductor layer and the fourth semiconductor layer form a NPN structure or a PNP structure.

[0029] Optionally, further comprising:

[0030] An encapsulation layer is located on the side of the light emitting device away from the driving substrate; the encapsulation layer comprises at least one organic layer and at least one inorganic layer; the organic layer and the inorganic layer are alternately stacked.

[0031] In a second aspect, the present application provides a display device comprising the display panel of the first aspect of the present application.

[0032] The technical scheme provided by the present application, by setting the second cathode and the first charge blocking layer in the first light emitting device of the first pixel area, and setting the second cathode between the charge generation layer and the first light emitting layer; the first charge blocking layer is located between the second cathode and the charge generation layer or between the second light emitting layer and the charge generation layer, resulting in that the second light emitting layer does not emit light, so that the light emitting color of the first pixel area is the light emitting color of the first light emitting layer of the first light emitting device, so that the light emitting layer does not need to be set in the first pixel area, and the light of corresponding color can be emitted in the region, so that the light emitted by the first light emitting device of the first pixel area can reach the display surface of the display panel without passing through the light filtering layer, thereby the light emitting efficiency of the first pixel area can be improved, so that when higher brightness needs to be displayed, the first light emitting device of the first pixel area can present higher display light brightness without providing higher electrical signals for the first light emitting device of the first pixel area, which is beneficial to reduce the power consumption and heat of the display panel and prolong the service life of the display panel. BRIEF DESCRIPTION OF DRAWINGS

[0033] Figure 1 A structural schematic diagram of a display panel provided by an embodiment of the present application is shown in the figure;

[0034] Figure 2 A structural schematic diagram of a light emitting device provided by an embodiment of the present application is shown in the figure;

[0035] Figure 3 A structural schematic diagram of a first light emitting device provided by an embodiment of the present application is shown in the figure;

[0036] Figure 4 A structural schematic diagram of another first light emitting device provided by an embodiment of the present application is shown in the figure;

[0037] Figure 5 A structural schematic diagram of another first light emitting device provided by an embodiment of the present application is shown in the figure;

[0038] Figure 6 A structural schematic diagram of another first light emitting device provided by an embodiment of the present application is shown in the figure;

[0039] Figure 7 A structural schematic diagram of a second light emitting device provided by an embodiment of the present application is shown in the figure;

[0040] Figure 8 A structural schematic diagram of a cathode transmission line of a display panel provided by an embodiment of the present application is shown in the figure;

[0041] Figure 9 A structural schematic diagram of another second light emitting device provided by an embodiment of the present application is shown in the figure;

[0042] Figure 10 A schematic structural diagram of another second light-emitting device provided in an embodiment of the present invention;

[0043] Figure 11 A schematic structural diagram of another display panel provided by an embodiment of the present invention;

[0044] Figure 12 A schematic structural diagram of another second light-emitting device provided in an embodiment of the present invention;

[0045] Figure 13 A schematic structural diagram of a second light-emitting device provided in an embodiment of the present invention;

[0046] Figure 14 A schematic structural diagram of a display device provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0047] The present invention will be further described in detail below with reference to the accompanying drawings and examples. It will be understood that the specific embodiments described herein are intended only to illustrate the present invention and are not intended to limit the present invention. It should also be noted that, for ease of description, the accompanying drawings only illustrate portions relevant to the present invention, not all structures.

[0048] Figure 1 A schematic structural diagram of a display panel provided by an embodiment of the present invention is shown in FIG. Figure 1 As shown, the display panel 100 includes: multiple first pixel areas 110, multiple second pixel areas 120 and multiple third pixel areas 130; the first pixel areas 110, the second pixel areas 120 and the third pixel areas 130 have different light emission colors. For example, the first pixel area 110, the second pixel area 120 and the third pixel area 130 can emit blue, green and red light respectively, so that the display panel can achieve color display.

[0049] Figure 2 A schematic diagram of the structure of a light emitting device provided by an embodiment of the present invention, with reference to Figure 1 and Figure 2 The display panel 100 also includes a driving substrate 140 and a plurality of light-emitting devices 150; the light-emitting device 150 is located on one side of the driving substrate 140; the light-emitting device 150 includes a first anode 101, a first light-emitting layer 102, a charge generation layer 103, a second light-emitting layer 104 and a first cathode 105 stacked in sequence; the charge generation layer 103 generates electrons and holes under the action of an electric field; the light of different colors generated by the first light-emitting layer 102 and the second light-emitting layer 104 are combined to form white light.

[0050] The drive substrate 140 may include multiple drive circuits 141, each electrically connected to a respective light-emitting device 150 to provide an electrical signal to the first anode 101 of the light-emitting device 150, thereby driving the light-emitting device 150 to emit light. The drive circuits 141 in the drive substrate 140 may control the color and brightness of light emitted by the light-emitting device 150 by controlling the signal applied to the light-emitting device 150. The electrical signal provided to the first anode 101 of the light-emitting device 150 may be a voltage or a current.

[0051] The material of the first anode 101 may include an anode material such as silver, and the material of the first cathode 105 may include a cathode material such as ITO or IZO. The first light-emitting layer 102 may include a hole injection layer HIL-2, a hole transport layer HTL-2, a light-emitting layer EML-2, an electron transport layer ETL-2, and an electron injection layer EIL-2, which are stacked in sequence. The second light-emitting layer 104 may include a hole injection layer HIL-1, a hole transport layer HTL-1, a light-emitting layer EML-1, an electron transport layer ETL-1, and an electron injection layer EIL-1, which are stacked in sequence.

[0052] It can be understood that the electron injection layer EIL plays the role of modifying the cathode and transferring electrons to the electron transport layer ETL; the electron transport layer ETL is responsible for transferring electrons from the cathode to the light-emitting layer EML of the device; the hole injection layer HIL can modify the anode of the device and can smoothly inject holes from the anode into the hole transport layer HTL; the hole transport layer HTL is responsible for transporting holes to the light-emitting layer EML; the light-emitting layer EML is the film layer where electrons and holes of the device recombine to generate photons.

[0053] Specifically, by applying an electric signal to the first anode 101 and the first cathode 105 respectively, the first anode 101 provides holes, the first cathode 105 provides electrons, and after the electric signal is applied to the first anode 101 and the first cathode 105, an electric field is generated, and the charge generation layer 103 can generate electrons and holes under the action of the electric field; at this time, the holes provided by the first anode 101 will be transmitted to the light-emitting layer EML-2 in turn through the hole injection layer HIL-2 and the hole transport layer HTL-2; and the electrons generated by the charge generation layer 103 are transmitted to the light-emitting layer EML-2 in turn through the electron injection layer EIL-2 and the electron transport layer ETL-2, so that the electrons and holes in the light-emitting layer EML-2 are combined to excite photons and emit light. Similarly, the electrons provided by the first cathode 105 will be transmitted to the light-emitting layer EML-1 in turn through the electron injection layer EIL-1 and the electron transport layer ETL-1; and the holes generated by the charge generation layer 103 are transmitted to the light-emitting layer EML-1 in turn through the hole injection layer HIL-1 and the hole transport layer HTL-1, so that the electrons and holes in the light-emitting layer EML-1 are combined to excite photons and emit light; the light-emitting layer EML-1 and the light-emitting layer EML-2 can have the same or different light-emitting colors, and when the light-emitting colors of the light-emitting layer EML-1 and the light-emitting layer EML-2 are different, the light emitted by the light-emitting layer EML-1 and the light-emitting layer EML-2 can be combined into white light, and in an exemplary embodiment, the light emitted by the light-emitting layer EML-2 can be blue, and the light emitted by the light-emitting layer EML-1 can include green and red. The light emitted by the light-emitting layer EML-1 and the light-emitting layer EML-2 can pass through the first cathode 105 to the display surface of the display panel 100.

[0054] It can be understood that in an exemplary embodiment, the light-emitting devices in different color pixel regions can all be white OLEDs, and at this time, other film layers such as color filter layers are needed to make different pixel regions present different colors of light, and the transmittances of different color filter films are different, which makes different pixel regions have different light-emitting efficiencies when the same electric signal is applied to the light-emitting devices of the pixel regions, which will affect the display uniformity of the display panel. If it is desired to make the pixel region to which the color filter film with lower transmittance belongs have higher light-emitting brightness, a larger electric signal needs to be provided to the pixel region, which will result in a display panel with higher power consumption, which is not conducive to the long service life of the light-emitting device.

[0055] To solve the above problems, Figure 3 A structure diagram of a first light-emitting device is provided for the embodiments of the present application, which is combined with reference to Figure 2 and Figure 3As shown, at least the light-emitting device located in the first pixel region 110 can be set as a first light-emitting device 151; the first light-emitting device 151 further comprises the second cathode 106 and the first charge blocking layer 107 on the basis of the structure of the light-emitting device 150; in the same first light-emitting device 151, the second cathode 106 is located between the charge generation layer 103 and the first light-emitting layer 102; the first charge blocking layer 107 is located between the second cathode 106 and the charge generation layer 103; the first charge blocking layer 107 prevents the holes generated by the charge generation layer 103 from transmitting to the second light-emitting layer 104; wherein the light-emitting color of the first light-emitting layer 102 of the first light-emitting device 151 is the same as the light-emitting color of the first pixel region 110.

[0056] Specifically, the premise for the first light-emitting layer 102 and the second light-emitting layer 104 in the light-emitting device 150 to emit photons is that there are holes and electrons to recombine therein, therefore, when only the first light-emitting layer 102 has holes and electrons to recombine therein, and the second light-emitting layer 104 does not have holes and electrons to recombine therein, it can be made that the light-emitting device 150 only emits the light generated by the first light-emitting layer 102. At this time, by setting the first charge blocking layer 107 in the first light-emitting device 151, the first charge blocking layer 107 can prevent the holes from transmitting to the second light-emitting layer 104, and the electrons cannot recombine with the holes in the second light-emitting layer 104, so that the second light-emitting layer 104 cannot emit photons; at the same time, by setting the second cathode 106 in the first light-emitting device 151, the first anode 101 and the second cathode 106 can provide holes and electrons respectively when electric signals are applied to the first anode 101 and the second cathode 106 respectively, at this time, the holes provided by the first anode 101 will transmit to the light-emitting layer EML-2 in turn through the hole injection layer HIL-2 and the hole transport layer HTL-2; and the electrons provided by the second cathode 106 will transmit to the light-emitting layer EML-2 in turn through the electron injection layer EIL-2 and the electron transport layer ETL-2, so that the electrons and the holes recombine in the light-emitting layer EML-2 to excite photons and emit light. In this way, only the first light-emitting layer 102 in the first light-emitting device 151 can emit light, so that the light emitted by the first light-emitting device 151 is the light emitted by the first light-emitting layer 102; when the color of the light emitted by the first light-emitting layer 102 is the same as the color of the light required to be presented by the first pixel region 110, it is not necessary to set a color filter layer in the first pixel region 110, so that the light emitted by the first light-emitting device 151 can directly reach the display surface of the display panel 100 without passing through the color filter layer, thereby being able to reduce the loss of the light emitted by the first light-emitting device 151 and improve the light-emitting efficiency of the first pixel region 110.

[0057] In addition, when the electric signal is applied to the first anode 101, the first cathode 105 and the second cathode 106 respectively, the first anode 101 provides holes, and the first cathode 105 and the second cathode 106 provide electrons respectively, at this time, whether the charge generation layer 103 generates electrons and holes or not is related to the voltage difference of the electric signal applied to the first anode 101, the first cathode 105 and the second cathode 106, in an optional embodiment, the electric signal applied to the first anode 101 is 3V, the electric signal applied to the first cathode 105 and the second cathode 106 is -4.5V and -1.5V respectively, at this time, the charge generation layer 103 can generate electrons and holes; however, due to the first charge blocking layer 107 in the first light emitting device 151, even if the charge generation layer 103 generates electrons and holes, the first charge blocking layer 107 can block the holes generated by the charge generation layer 103 from transmitting to the second light emitting layer 104, and can also ensure that the second light emitting layer 104 cannot generate photons due to the recombination of electrons and holes, that is, the light emitted by the first light emitting device 151 is still the light emitted by the first light emitting layer 102. Alternatively, when the first light emitting device 151 does not need to emit light, the electric signal applied to the first anode 101 is stopped, at this time, even if the electric signal is applied to the first cathode 105 and / or the second cathode 106, the second light emitting layer 104 of the first light emitting device 151 cannot emit light.

[0058] Therefore, when the first pixel area 110 needs to emit light, the corresponding electric signal can be applied to the first anode 101 and the second cathode 106 of the first light emitting device 151 respectively, that is, the light emitted by the first light emitting device 151 is only the light emitted by the first light emitting layer 102; and when the first pixel area 110 does not need to emit light, the electric signal applied to the first anode 101 is stopped, so that the first light emitting layer 102 and the second light emitting layer 104 of the first light emitting device 151 cannot emit light.

[0059] In an optional embodiment, the first pixel area can be a blue pixel area, the first light emitting layer can be a blue light emitting layer, that is, the light emitted by the first light emitting layer is blue light, and the second light emitting layer can include a red light emitting layer and / or a green light emitting layer.

[0060] It should be noted that the technical solutions of the embodiments of the present application are exemplarily described above by taking the case that the first charge blocking layer 107 is located between the second cathode 106 and the charge generation layer 103 as an example, and in the embodiments of the present application, the first charge blocking layer 107 can be located between the first anode 101 and the charge generation layer 103, or the first charge blocking layer 107 can be located between the first cathode 105 and the charge generation layer 103. Figure 4As shown, the first charge blocking layer 107 can also be located between the second light emitting layer 104 and the charge generation layer 103, and the working principle in this arrangement is similar to the working principle of the first charge blocking layer 107 located between the second cathode 106 and the charge generation layer 103, which will not be described here. For the convenience of description, the technical solutions of the embodiments of the present application are exemplarily described with the first charge blocking layer 107 located between the second cathode 106 and the charge generation layer 103 as an example without special limitation.

[0061] The technical solutions provided by the embodiments of the present application cause the second light emitting layer not to emit light, so that the light emitting color of the first pixel area is the light emitting color of the first light emitting layer of the first light emitting device, thereby making the first pixel area emit light of the corresponding color without the need to set a filter layer in the first pixel area, so that the light emitted by the first light emitting device of the first pixel area can reach the display surface of the display panel without passing through the filter layer, thereby improving the light emitting efficiency of the first pixel area, so that the first pixel area can present a higher display light emitting brightness without the need to provide a higher electrical signal for the first light emitting device of the first pixel area, which is beneficial to reduce the power consumption and heat of the display panel and prolong the service life of the display panel.

[0062] Optionally, in combination with reference to Figures 1-3 The display panel 100 further includes a color filter layer 170 located on the side of the light emitting device 150 away from the driving substrate 140; the color filter layer 170 includes a first filter layer 171 and a second filter layer 172 located in the second pixel area 120 and the third pixel area 130, respectively, and the first pixel area 110 is not provided with a color filter layer.

[0063] The main constituent materials of the color filter layer include resin and pigment, etc. The color filter layer can color the light when the light is transmitted. When the light emitting device 150 in the second pixel area 120 and the third pixel area 130 emits white light, the first filter layer 171 and the second filter layer 172 need to be arranged in the second pixel area 120 and the third pixel area 130, respectively. The first filter layer 171 in the second pixel area 120 can only allow the light with the same color as the color of the light required to be presented by the second pixel area 120 to be transmitted. The second filter layer 172 in the third pixel area 130 can only allow the light with the same color as the color of the light required to be presented by the third pixel area 130 to be transmitted. In this way, by arranging the first filter layer 171 and the second filter layer 172, the white light emitted by the light emitting device 150 in the second pixel area 120 and the third pixel area 130 can be filtered, so that the display panel 100 can realize color display.

[0064] Correspondingly, since the first light emitting device 151 in the first pixel area 110 can emit light with the same color as the color of the light required to be presented by the first pixel area 110, there is no need to arrange a filter layer in the first pixel area 110. The light emitted by the first light emitting device 151 can reach the display surface of the display panel 100 without passing through the filter layer, so that the light emission rate of the first pixel area 110 can be improved, and the first light emitting device 151 in the first pixel area 110 can have a higher display luminance without applying a higher electrical signal.

[0065] In an optional embodiment, when the color filter layer is not arranged in the first pixel area 110, a material with high light transmittance such as resin or optical glue can be filled in the area 173 to which the first pixel area 110 belongs, so that the first pixel area 110 has the same thickness as the second pixel area 120 and the third pixel area 130, and the display panel 100 has a flat display surface.

[0066] In an optional embodiment, the first light-emitting layer 102 of the first light-emitting device 151 emits blue light, and the first filter layer 171 and the second filter layer 172 are red and green, respectively. When the light-emitting device 150 in the second pixel area 120 and the third pixel area 130 emits white light, the light-emitting device 150 can emit light of different colors after passing through the first filter layer 171 and the second filter layer 172, i.e., the first filter layer 171 can only allow red light to pass through, and the second filter layer 172 can only allow green light to pass through, so that the light-emitting device 150 can emit light of corresponding colors after passing through the filter layers of different colors, and the light emitted by the first light-emitting device 151 of the first pixel area 110 can be emitted to the display surface of the display panel 100 without passing through the filter layer, so that the display panel 100 can realize color display. Furthermore, the light-emitting efficiency of the first pixel area 110 can be improved, so that the first light-emitting device 151 of the first pixel area 110 can present higher display light brightness without providing a higher electrical signal, which is beneficial to reduce the power consumption and heat of the display panel 100 and prolong the service life of the display panel.

[0067] It can be understood that the above description is only an example in which the first light-emitting layer of the first light-emitting device of the first pixel area emits blue light, and the first filter layer and the second filter layer are red and green, respectively. The first light-emitting layer of the first light-emitting device of the first pixel area can also emit green light, and the first filter layer and the second filter layer can be red and blue, respectively, and other settings, and the technical principles are similar to the above technical principles, which will not be described here.

[0068] Optionally, Figure 5 Another structure of the first light-emitting device is provided for the embodiment of the present application, as shown in Figure 5 The charge generation layer 103 includes a first semiconductor layer 1031 and a second semiconductor layer 1032 which are stacked, and one of the first semiconductor layer 1031 and the second semiconductor layer 1032 is used to generate holes, and the other is used to generate electrons; the first charge blocking layer 107 includes a third semiconductor layer 1071. In the same first light-emitting device 151, when the third semiconductor layer 1071 is located on the side of the first semiconductor layer 1031 away from the second semiconductor layer 1032, the third semiconductor layer 1071 has the same doping type as the second semiconductor layer 1032.

[0069] For example, when the doping type of the first semiconductor layer 1031 is P type, the doping types of the second semiconductor layer 1032 and the third semiconductor layer 1071 are both N type. At this time, the charge generation layer 103 and the first charge blocking layer 107 in the first light-emitting device 151 form an NPN structure, i.e., the stacked structure of the second semiconductor layer 1032, the first semiconductor layer 1031 and the third semiconductor layer forms an NPN structure.

[0070] In another optional embodiment, if Figure 6 As shown, the third semiconductor layer 1071 may also be located on the side of the second semiconductor layer 1032 away from the first semiconductor layer 1031. In this case, the third semiconductor layer 1071 has the same doping type as the first semiconductor layer 1031. In the same first light-emitting device 151, when the doping types of the first semiconductor layer 1031 and the third semiconductor layer 1071 are both P-type and the doping type of the second semiconductor layer 1032 is N-type, the stacked structure of the first semiconductor layer 1031, the second semiconductor layer 1032, and the third semiconductor layer 1071 forms a PNP structure.

[0071] Optional, Figure 7 A schematic structural diagram of a second light emitting device provided in an embodiment of the present invention is shown in FIG. Figure 7 As shown, in the display panel 100, the light-emitting device located in the second pixel area 120 and / or the third pixel area 130 is a second light-emitting device 152; the second light-emitting device 152 also includes a third cathode 108; in the same second light-emitting device 152, the third cathode 108 is located between the first light-emitting layer 102 and the charge generation layer 103.

[0072] Specifically, when the second light-emitting device 152 needs to emit light, it can achieve light emission by applying electrical signals to the first anode 101 and the first cathode 105 respectively, or by applying electrical signals to the first anode 101, the first cathode 105, and the third cathode 108 respectively. The electrical signal applied by the third cathode 108 can correspondingly increase the number of electrons in the first light-emitting layer 102 and the number of holes in the second light-emitting layer 104, thereby improving the light emission efficiency of the second light-emitting device 152. When the second light-emitting device 152 does not need to emit light, no electrical signal is applied to the first anode 101. At this time, even if electrical signals are applied to the first cathode 105 and / or the third cathode 108, the second light-emitting device 152 cannot emit light.

[0073] It is understandable that the light-emitting devices in the second pixel area and the third pixel area can both be second light-emitting devices, or only the light-emitting device in one of the pixel areas can be a second light-emitting device. It can be set as needed, and the embodiment of the present invention does not make specific limitations on this.

[0074] Optionally, the third cathode 108 is arranged in the same layer as the second cathode 106. In this way, there is no need to set additional film layers for the third cathode 108 and the second cathode 106 respectively, thereby reducing the number of film layers of the display panel 100, simplifying the process of the display panel 100, reducing the preparation cost of the display panel 100, and improving the production efficiency of the display panel 100.

[0075] Optional, Figure 8A schematic structural diagram of a cathode transmission line of a display panel provided by an embodiment of the present invention is shown in FIG. Figure 8 As shown, the display panel 100 also includes: a first cathode transmission line 21 and a second cathode transmission line 22 insulated from each other; the first cathode transmission line 21 is electrically connected to the first cathode 105 of each light-emitting device 150; the second cathode transmission line 22 is electrically connected to the second cathode 106 of the first light-emitting device 151 and the third cathode 108 of the second light-emitting device 152 respectively; the driving substrate 140 includes a plurality of driving circuits 141; each driving circuit 141 is electrically connected to the first anode 101 of each light-emitting device 150 respectively.

[0076] Specifically, an insulating structure can be provided between the first cathode transmission line 21 and the second cathode transmission line 22 so that the signals transmitted by the two do not affect each other and are mutually insulated. The first cathode transmission line 21 provides an electrical signal to the first cathode 105 of each light-emitting device 150, enabling the first cathode 105 to generate electrons. The second cathode transmission line 22 provides electrical signals to the second cathode 106 of the first light-emitting device 151 and the third cathode 108 of the second light-emitting device 152, respectively, enabling the second cathode 106 and the third cathode 108 to generate electrons. The driving circuit 141 of the driving substrate 140 can provide electrical signals to the first anode 101 of each light-emitting device 150, respectively, enabling the first anode 101 to generate holes. In this way, by applying electrical signals to the first anode 101, the first cathode 105, and the second cathode 106 or the third cathode 108 in the same light-emitting device, the light-emitting device 150 can emit light normally.

[0077] It will be appreciated that the above description only uses the example of configuring the second cathode and the first charge blocking layer in the first light-emitting device of the first pixel region as an example to illustrate the light emission color of the first pixel region. In embodiments of the present invention, when the second or third pixel regions have the same configuration, this configuration can also be used to change the light emission color of the corresponding pixel regions. The technical principles behind this are similar to those for the first pixel region described above and will not be further elaborated here.

[0078] Optional, Figure 9 A schematic structural diagram of another second light emitting device provided in an embodiment of the present invention is shown in FIG. Figure 9As shown in the display panel 100, the light emitting device located in the second pixel area 120 is a second light emitting device 152; the second light emitting device 152 further comprises a second anode 109 and a second charge blocking layer 111; in the same second light emitting device 152, the second anode 109 is located between the charge generation layer 103 and the second light emitting layer 104; the second charge blocking layer 111 is located between the second anode 109 and the charge generation layer 103; the second charge blocking layer 111 prevents the electron from transmitting to the first light emitting layer 102; wherein the light emitting color of the second light emitting layer 104 of the second light emitting device 152 is the same as the light emitting color of the second pixel area 120.

[0079] Specifically, since the premise of the first light emitting layer 102 and the second light emitting layer 104 in the light emitting device 150 emitting photons is that there are holes and electrons to recombine, therefore, when only the first light emitting layer 102 has holes and electrons to recombine, and the second light emitting layer 104 does not have holes and electrons to recombine, it can make the light emitting device 150 only emit the light generated by the first light emitting layer 102. At this time, by setting the second charge blocking layer 111 in the second light emitting device 152, the second charge blocking layer 111 can prevent the electron from transmitting to the first light emitting layer 102, and the hole cannot recombine with the electron in the first light emitting layer 102, so that the first light emitting layer 102 cannot emit photons; at the same time, by setting the second anode 109 in the second light emitting device 152, when the second anode 109 and the first cathode 105 provide holes and electrons respectively by applying an electrical signal to the second anode 109 and the first cathode 105 respectively, at this time, the holes provided by the second anode 109 will be transmitted to the light emitting layer EML-1 in turn through the hole injection layer HIL-1 and the hole transport layer HTL-1; and the electrons provided by the first cathode 105 will be transmitted to the light emitting layer EML-1 in turn through the electron injection layer EIL-1 and the electron transport layer ETL-1, so that the electrons and holes recombine in the light emitting layer EML-1 to emit photons. In this way, only the second light emitting layer 104 in the second light emitting device 152 can emit light, so that the light emitted by the second light emitting device 152 is the light emitted by the second light emitting layer 104; when the color of the light emitted by the second light emitting layer 104 is the same as the color of the light required to be presented by the second pixel area 120, it will not be necessary to set a color filter layer in the second pixel area 120, so that the light emitted by the second light emitting device 152 can directly reach the display surface of the display panel 100 without passing through the color filter layer, thereby reducing the loss of the light emitted by the second light emitting device 152 and improving the light emitting efficiency of the second pixel area 120.

[0080] In addition, when the electric signals are applied to the first anode 101, the first cathode 105 and the second anode 109 respectively, holes are provided by the first anode 101, electrons are provided by the first cathode 105, and the charge generation layer 103 generates electrons and holes in relation to the voltage difference of the electric signals applied to the first anode 101, the second anode 109 and the first cathode 105. In an optional embodiment, the electric signal applied to the first anode 101 is 3V, the electric signals applied to the second anode 109 and the first cathode 105 are -1.5V and -4.5V respectively, and the charge generation layer 103 can generate electrons and holes. However, since the second charge blocking layer 111 is present in the second light emitting device 152, the second charge blocking layer 111 can block the electrons generated by the charge generation layer 103 from being transmitted to the first light emitting layer 102, and can also ensure that the first light emitting layer 102 does not generate photons by recombination of electrons and holes, i.e. the light emitted by the second light emitting device 152 is still the light emitted by the second light emitting layer 104. Alternatively, when the second light emitting device 152 does not need to emit light, the electric signal applied to the first cathode 105 is stopped, and the first light emitting layer 102 of the second light emitting device 152 cannot emit light even if the electric signals are applied to the first anode 101 and / or the second anode 109.

[0081] Therefore, when the second pixel region 120 needs to emit light, the corresponding electric signals can be applied to the second anode 109 and the first cathode 105 of the second light emitting device 152 respectively, so that the light emitted by the second light emitting device 152 is only the light emitted by the second light emitting layer 104. When the second pixel region 120 does not need to emit light, the electric signal applied to the first cathode 105 is stopped, so that the first light emitting layer 102 and the second light emitting layer 104 of the second light emitting device 152 cannot emit light. Therefore, the second pixel region can emit light of the corresponding color without the need of a filter layer, and the light emitted by the second light emitting device of the second pixel region can reach the display surface of the display panel without the need of passing through the filter layer. Therefore, the light emission rate of the second pixel region can be improved, and the second light emitting device of the second pixel region can present a higher display light emission brightness without the need of providing a higher electric signal, which is beneficial to reduce the power consumption and heat of the display panel and prolong the service life of the display panel.

[0082] In an optional embodiment, the second pixel region can be a green pixel region, and the first light emitting layer can be a blue or red light emitting layer, i.e. the light emitted by the second light emitting layer is green light, and the first light emitting layer can include a blue light emitting layer or a red light emitting layer.

[0083] It should be noted that the above only exemplarily takes the case that the second charge blocking layer 111 is located between the second anode 109 and the charge generation layer 103 as an example to exemplarily describe the technical solutions of the embodiments of the present application, and in the embodiments of the present application, as shown in Figure 10 the second charge blocking layer 111 can also be located between the first light emitting layer 102 and the charge generation layer 103, and the working principle in this arrangement is similar to the working principle of the case that the second charge blocking layer 111 is located between the second anode 109 and the charge generation layer 103, which will not be described here. For the convenience of description, under the premise of no special limitation, the technical solutions of the embodiments of the present application are exemplarily described taking the case that the second charge blocking layer 111 is located between the second anode 109 and the charge generation layer 103 as an example.

[0084] Optionally, Figure 11 Another structural schematic diagram of a display panel provided by the embodiments of the present application is shown in Figure 11 The display panel 100 further includes a color filter layer 180 located on the side of the light emitting device 150 away from the driving substrate 140, and the color filter layer 183 is located in the third pixel area 130, and the first pixel area 110 and the second pixel area 120 are not provided with the color filter layer 183.

[0085] The color filter layer 183 is mainly composed of resin and pigment, etc., and can color the light when the light is transmitted. When the light emitting device 150 located in the third pixel area 130 emits white light, the color filter layer 183 needs to be arranged in the third pixel area 130; the color filter layer 183 in the third pixel area 130 can only make the light with the same color as the color of the light required to be presented by the third pixel area 130 to be transmitted, and the color filter layer 183 in the third pixel area 130 can only make the light with the same color as the color of the light required to be presented by the third pixel area 130 to be transmitted, so that by arranging the color filter layer 183, the white light can be filtered when the light emitting device 150 located in the third pixel area 130 emits white light, and the display panel 100 can realize color display.

[0086] Correspondingly, since the first light emitting device 151 in the first pixel region 110 is capable of emitting light of the same color as the light required to be presented by the first pixel region 110, and the second light emitting device 152 in the second pixel region 120 is capable of emitting light of the same color as the light required to be presented by the second pixel region 120, there is no need to arrange a color filter layer in the first pixel region 110 and the second pixel region 120, so that the light emitted by the first light emitting device 151 and the second light emitting device 152 can reach the display surface of the display panel 100 without passing through the color filter layer, thereby improving the light extraction efficiency of the first pixel region 110 and the second pixel region 120, and further ensuring that the first pixel region 110 and the second pixel region 120 have a higher display luminance without applying a higher electrical signal to the first light emitting device 151 and the second light emitting device 152 in the first pixel region 110 and the second pixel region 120.

[0087] In an optional embodiment, when the color filter layer is not arranged in the first pixel region 110 and the second pixel region 120, a material with a high light transmittance such as resin or optical glue can be filled in the area 181 to which the first pixel region 110 belongs and the area 182 to which the second pixel region 120 belongs, so that the first pixel region 110 and the second pixel region 120 have the same thickness as the third pixel region 130, and the display panel 100 has a flat display surface.

[0088] In an optional embodiment, the first light emitting layer 102 of the first light emitting device 151 has a blue light emitting color, the second light emitting layer 104 of the second light emitting device 152 has a red light emitting color, and the color filter layer 183 is green. When the light emitting device 150 in the third pixel region 130 emits white light, the green color filter layer 183 has a green coloring effect when the white light passes through the green color filter layer 183, i.e., the color filter layer 183 can only allow green light to pass through, so that the light emitting device 150 can emit light of a corresponding color after passing through the color filter layer 183, and the light emitted by the first light emitting device 151 in the first pixel region 110 and the light emitted by the second light emitting device 152 in the second pixel region 120 can be emitted to the display surface of the display panel 100 without passing through the color filter layer, so that the display panel 100 realizes color display. Further, the light extraction efficiency of the first pixel region 110 and the second pixel region 120 can be improved, so that when a higher luminance needs to be displayed, the first light emitting device 151 in the first pixel region 110 and the second light emitting device 152 in the second pixel region 120 can present a higher display luminance without a higher electrical signal being provided, which is beneficial to reduce the power consumption and heat of the display panel 100 and prolong the service life of the display panel.

[0089] It will be appreciated that the above description uses only an example in which the first light-emitting layer of the first light-emitting device in the first pixel region emits blue light, the second light-emitting layer of the second light-emitting device in the second pixel region emits red light, and the color of the color filter layer is green. Alternatively, the first light-emitting layer of the first light-emitting device in the first pixel region emits green light, the second light-emitting layer of the second light-emitting device in the second pixel region emits blue light, and the color filter layer emits red light. The technical principles behind these arrangements are similar to those described above and are not further elaborated upon herein.

[0090] Optional, Figure 12 A structural diagram of another second light emitting device provided in an embodiment of the present invention is shown in FIG. Figure 12 As shown, the charge generation layer 103 includes a first semiconductor layer 1031 and a second semiconductor layer 1032 that are stacked; one of the first semiconductor layer 1031 and the second semiconductor layer 1032 is used to generate holes, and the other is used to generate electrons; the second charge blocking layer 111 includes a fourth semiconductor layer 1111; in the same second light-emitting device 152, when the fourth semiconductor layer 1111 is located on the side of the first semiconductor layer 1031 away from the second semiconductor layer 1032, the fourth semiconductor layer 1111 has the same doping type as the second semiconductor layer 1032.

[0091] For example, when the doping type of the first semiconductor layer 1031 is P-type, the doping types of the second semiconductor layer 1032 and the fourth semiconductor layer 1111 are both N-type. In this case, the charge generation layer 103 and the second charge blocking layer 111 in the second light-emitting device 152 form an NPN structure, that is, the stacked structure of the first semiconductor layer 1031, the second semiconductor layer 1032, and the fourth semiconductor layer 1111 forms an NPN structure.

[0092] In another optional embodiment, if Figure 13 As shown, the fourth semiconductor layer 1111 may also be located on the side of the second semiconductor layer 1032 away from the first semiconductor layer 1031. In this case, the fourth semiconductor layer 1111 has the same doping type as the first semiconductor layer 1031. In the same second light-emitting device 152, when the doping types of the first semiconductor layer 1031 and the fourth semiconductor layer 1111 are both P-type and the doping type of the second semiconductor layer 1032 is N-type, the stacked structure of the first semiconductor layer 1031, the second semiconductor layer 1032, and the fourth semiconductor layer 1111 forms a PNP structure.

[0093] Optional, continue to refer to Figure 1 The display panel 100 further includes an encapsulation layer 160 located on a side of the light emitting device 150 away from the driving substrate 140 ; ​​the encapsulation layer 160 includes at least one organic layer and at least one inorganic layer; the organic layer and the inorganic layer are alternately stacked.

[0094] The encapsulation layer 160 mainly prevents water, fog or impurities in the external air from entering the light emitting device 150 to damage the structure of the light emitting device 150, so as to improve the service life of the light emitting device 150. The encapsulation layer 160 can be a thin film encapsulation layer, for example, a multilayer laminated encapsulation structure including an inorganic layer-organic layer-inorganic layer, which prevents water or fog from entering through the inorganic layer, and absorbs the entering impurities through the organic layer to ensure the encapsulation effect.

[0095] Based on the same inventive concept, the embodiment of the present application also provides a display device, which comprises the display panel of any of the embodiments of the present application. Therefore, the display device has the technical features and beneficial effects of the display panel provided by the embodiments of the present application, and the same parts can be referred to the description above, which will not be repeated here.

[0096] Exemplarily, Figure 14 The structural schematic diagram of a display device provided by the embodiment of the present application is shown in FIG. 2. As shown in FIG. 2, the display device 200 can be a VR glasses, and the lens of the VR glasses comprises the display panel 100 in the embodiment of the present application. In other embodiments, the display device 200 can also be other micro display devices, which will not be limited here in the embodiment. Figure 14

[0097] Since the display device provided by the embodiment of the present application comprises the display panel provided by any of the embodiments of the present application, the display device provided by the embodiment of the present application comprises the corresponding functional modules of the display panel, and can achieve the beneficial effects of the display panel provided by the embodiment of the present application. The technical details not described in detail in the above embodiments can be referred to the description of the display panel provided by the embodiment of the present application.

[0098] It should be noted that the above are only the preferred embodiments of the present application and the technical principles applied. Those skilled in the art will understand that the present application is not limited to the specific embodiments described herein, and those skilled in the art can make various obvious changes, re-adjustments, mutual combinations and substitutions without departing from the scope of the present application. Therefore, although the present application has been described in more detail through the above embodiments, the present application is not limited to the above embodiments, and can include more other equivalent embodiments without departing from the concept of the present application, and the scope of the present application is determined by the appended claims.​

Claims

1. A display panel, characterized by, The display panel comprises: a plurality of first pixel regions, a plurality of second pixel regions and a plurality of third pixel regions; the light-emitting colors of the first pixel regions, the second pixel regions and the third pixel regions are different; the display panel further comprises: a driving substrate; a plurality of light-emitting devices located on one side of the driving substrate; the light-emitting device comprises a first anode, a first light-emitting layer, a charge generation layer, a second light-emitting layer and a first cathode which are sequentially stacked; the charge generation layer generates electrons and holes under the action of an electric field; the first light-emitting layer and the second light-emitting layer generate different colors of light which recombine to form white light; the light-emitting device located in the first pixel region is a first light-emitting device; the first light-emitting device further comprises a second cathode and a first charge blocking layer; in the same first light-emitting device, the second cathode is located between the charge generation layer and the first light-emitting layer; the first charge blocking layer is located between the second cathode and the charge generation layer or between the second light-emitting layer and the charge generation layer; the first charge blocking layer prevents the transmission of holes to the second light-emitting layer; wherein the light-emitting color of the first light-emitting layer of the first light-emitting device is the same as the light-emitting color of the first pixel region.

2. The display panel of claim 1, wherein, Further comprising: a color filter layer located on the side of the light-emitting device away from the driving substrate; the color filter layer comprises a first filter layer and a second filter layer located in the second pixel region and the third pixel region respectively, and the first pixel region is not provided with the color filter layer.

3. The display panel of claim 1, wherein, The charge generation layer comprises a first semiconductor layer and a second semiconductor layer which are stacked; one of the first semiconductor layer and the second semiconductor layer is used to generate holes, and the other is used to generate electrons; the first charge blocking layer comprises a third semiconductor layer; in the same first light-emitting device, when the third semiconductor layer is located on the side of the first semiconductor layer away from the second semiconductor layer, the third semiconductor layer and the second semiconductor layer have the same doping type; or when the third semiconductor layer is located on the side of the second semiconductor layer away from the first semiconductor layer, the third semiconductor layer and the first semiconductor layer have the same doping type.

4. The display panel of claim 3, wherein, In the same first light-emitting device, the first semiconductor layer, the second semiconductor layer and the third semiconductor layer form an NPN structure or a PNP structure.

5. The display panel of claim 1, wherein, The light-emitting device located in the second pixel region and / or the third pixel region is a second light-emitting device; the second light-emitting device further comprises a third cathode; in the same second light-emitting device, the third cathode is located between the first light-emitting layer and the charge generation layer.

6. The display panel of claim 5, wherein, The third cathode and the second cathode are provided in the same layer.

7. The display panel according to claim 5, wherein: Further comprising: a first cathode transmission line and a second cathode transmission line which are insulated from each other; the first cathode transmission line is electrically connected with the first cathode of each light-emitting device; the second cathode transmission line is electrically connected with the second cathode of the first light-emitting device and the third cathode of the second light-emitting device respectively; the driving substrate comprises a plurality of driving circuits; each driving circuit is electrically connected with the first anode of each light-emitting device.

8. The display panel of claim 1, wherein, The light emitting device located at the second pixel region is a second light emitting device; the second light emitting device further comprises a second anode and a second charge blocking layer; In the same second light emitting device, the second anode is located between the charge generation layer and the second light emitting layer; the second charge blocking layer is located between the second anode and the charge generation layer or between the first light emitting layer and the charge generation layer; the second charge blocking layer prevents the transmission of electrons to the first light emitting layer; wherein the light emitting color of the second light emitting layer of the second light emitting device is the same as the light emitting color of the second pixel region.

9. The display panel of claim 8, wherein, Further comprising: A color filter layer located on the side of the light emitting device away from the driving substrate; the color filter layer is located in the third pixel region, and the first pixel region and the second pixel region are not provided with the color filter layer.

10. The display panel of claim 8, wherein, The charge generation layer comprises a first semiconductor layer and a second semiconductor layer arranged in a stack; one of the first semiconductor layer and the second semiconductor layer is used to generate holes, and the other is used to generate electrons; the second charge blocking layer comprises a fourth semiconductor layer; In the same second light emitting device, when the fourth semiconductor layer is located on the side of the first semiconductor layer away from the second semiconductor layer, the fourth semiconductor layer and the second semiconductor layer have the same doping type; Or, when the fourth semiconductor layer is located on the side of the second semiconductor layer away from the first semiconductor layer, the fourth semiconductor layer and the first semiconductor layer have the same doping type.

11. The display panel of claim 10, wherein, In the same second light emitting device, the stack structure of the first semiconductor layer, the second semiconductor layer and the fourth semiconductor layer constitutes an NPN structure or a PNP structure.

12. The display panel of claim 1, wherein, Further comprising: An encapsulation layer located on the side of the light emitting device away from the driving substrate; the encapsulation layer comprises at least one organic layer and at least one inorganic layer; The organic layer and the inorganic layer are arranged in an alternating stack.

13. A display device comprising: Comprise: The display panel of any one of claims 1-12.

Images