Display substrate, display device, and display driving method

Abstract

This invention provides a display substrate, a display device, and a display driving method. The display substrate includes a substrate, a pixel driving circuit located on the substrate, and a light-emitting unit. The light-emitting unit emits light under the drive of the pixel driving circuit. Each light-emitting unit includes multiple sets of target light-emitting units, and each set of multiple sets of target light-emitting units contains at least two target light-emitting units. The orthographic projections of different target light-emitting units in the same set overlap on the substrate. Embodiments of this invention help improve the resolution of the display device.

Description

Technical Field

[0001] The present invention relates to the field of display technology, and in particular to a display substrate, a display device, and a display driving method. Background Technology

[0002] With the development of display technology, users have an increasing demand for display devices with high resolution and brightness. In related technologies, the area occupied by the driving circuit is usually reduced by adjusting the area and layout of the driving circuit. However, this method may lead to a decrease in the reliability of the driving circuit. Therefore, it is relatively difficult to improve the resolution of the display device using existing methods. Summary of the Invention

[0003] This invention provides a display substrate, a display device, and a display driving method to address the problem that improving the resolution of display devices is relatively difficult in existing methods.

[0004] To solve the above problems, the present invention is implemented as follows:

[0005] In a first aspect, embodiments of the present invention provide a display substrate, including a substrate, a pixel driving circuit located on the substrate, and a light-emitting unit. The light-emitting unit emits light under the drive of the pixel driving circuit. The light-emitting unit includes multiple groups of target light-emitting units, and the number of target light-emitting units in each group is at least two. The orthographic projections of different target light-emitting units in the same group on the substrate overlap.

[0006] In some embodiments, the pixel driving circuit includes a target pixel driving circuit, wherein one target pixel driving circuit is used to drive a group of target light-emitting units to emit light.

[0007] In some embodiments, different target light-emitting units in the same group correspond to sub-pixels of different colors.

[0008] In some embodiments, different target light-emitting units in the same group correspond to sub-pixels in different pixels.

[0009] In some embodiments, the target pixel driving circuit includes at least two light emission control sub-circuits, one of which is used to control one of the target light emission units to emit light.

[0010] In some embodiments, the target pixel driving circuit includes a first driving sub-circuit, a second driving sub-circuit, and a detection control sub-circuit;

[0011] The input terminal of the detection and control sub-circuit is connected to the constant current signal terminal;

[0012] The input terminal of the first driving sub-circuit is connected to the output terminal of the detection control sub-circuit, and the first driving sub-circuit is connected to the first scan line and the first target light-emitting unit;

[0013] The data input terminal of the second driving sub-circuit is connected to the output terminal of the detection control sub-circuit, and the second driving sub-circuit is also connected to the second scan line and the second target light-emitting unit.

[0014] Secondly, embodiments of the present invention provide a display device comprising the display substrate described in any one of the above descriptions.

[0015] Thirdly, embodiments of the present invention provide a display driving method applied to the display device described above, the method comprising the following steps:

[0016] During the light emission stage, different target light emission units in the same group are controlled to emit light simultaneously or in a time-division manner.

[0017] In some embodiments, when controlling different target light-emitting units in the same group to emit light simultaneously, the method includes:

[0018] During the light emission period, the corresponding target light emission unit is controlled to emit light by the target light emission control sub-circuit in at least two light emission control sub-circuits, while the target light emission unit corresponding to the light emission control sub-circuit outside the target light emission control sub-circuit is in the off state.

[0019] In some embodiments, when controlling different target light-emitting units in the same group to emit light in a time-division manner, the method includes:

[0020] During the light-emitting period, the first target light-emitting unit is controlled to emit light by the first driving sub-circuit, and the second target light-emitting unit is controlled to emit light by the second driving sub-circuit.

[0021] In some embodiments, the method further includes:

[0022] During the voltage threshold detection period, the first threshold voltage of the driving transistor of the first target light-emitting unit and the second threshold voltage of the driving transistor of the second target light-emitting unit are detected by the detection control sub-circuit.

[0023] In the technical solution of this invention, the light-emitting unit includes multiple sets of target light-emitting units, and the orthographic projections of the same set of target light-emitting units on the substrate overlap. In this way, more light-emitting units can be arranged within the same area, that is, more sub-pixels can be set, thereby helping to improve the resolution of the display device. Attached Figure Description

[0024] To more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings used in the description of the embodiments of the present invention will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0025] Figure 1 This is a schematic diagram of the structure of the display substrate provided in an embodiment of the present invention;

[0026] Figure 2 This is a schematic diagram of the arrangement of the light-emitting units according to an embodiment of the present invention;

[0027] Figure 3 This is another schematic diagram of the arrangement of the light-emitting units according to an embodiment of the present invention;

[0028] Figure 4 This is another schematic diagram of the arrangement of the light-emitting units according to an embodiment of the present invention;

[0029] Figure 5 This is a circuit diagram of the pixel driving circuit according to Embodiment 1 of the present invention;

[0030] Figure 6 yes Figure 5 Circuit diagram of the detection control sub-circuit;

[0031] Figure 7 yes Figure 5 The driving timing diagram of the pixel driving circuit is shown.

[0032] Figure 8 This is a circuit diagram of another pixel driving circuit according to an embodiment of the present invention;

[0033] Figure 9 yes Figure 8 The driving timing diagram of the pixel driving circuit is shown. Detailed Implementation

[0034] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0035] In the embodiments of this invention, the terms "first," "second," etc., are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion. For example, a process, method, system, product, or device that includes a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to these processes, methods, products, or devices. Additionally, the use of "and / or" in this application indicates at least one of the connected objects, such as A and / or B and / or C, representing seven possibilities: including A alone, B alone, C alone, and the presence of both A and B, both B and C, both A and C, and the presence of A, B, and C.

[0036] This invention provides a display substrate.

[0037] In one embodiment, the substrate, the pixel driving circuit located on the substrate, and the light-emitting unit are included, the light-emitting unit emitting light under the drive of the pixel driving circuit. The light-emitting unit includes multiple groups of target light-emitting units, where the target light-emitting units may be some or all of the light-emitting units in the light-emitting unit. The target light-emitting units are divided into multiple groups, and the number of target light-emitting units in each group is at least two. In this embodiment, two target light-emitting units are used as a group for illustrative purposes.

[0038] like Figure 1 As shown, in one embodiment, the display substrate includes a substrate 101, a buffer layer 102, a shielding layer 103, a semiconductor layer 104, a first gate insulating layer 105, a first gate layer 106, a second gate insulating layer 104, a second gate layer 108, a dielectric layer 109, a source / drain metal layer 110, a first planarization layer 111, a first electrode layer 112, a first pixel defining layer 113, a first light-emitting layer 114, a support structure 115, a second electrode layer 116, a third insulating layer 117, a third electrode layer 118, a second light-emitting layer 119, a second pixel defining layer 120, a second planarization layer 121, a charge generation layer 122, a conductive connection layer 123, an encapsulation layer 124, and a cover plate 125. The conductive connection layer connects the first electrode layer and the charge generation layer.

[0039] In the technical solution of this embodiment, the portion where the first electrode layer 112 is connected to the first light-emitting layer 114, the first light-emitting layer 114 and the second electrode layer 116 constitute one of the light-emitting units in a group of target light-emitting units, and the charge generation layer, the second light-emitting layer and the third electrode layer constitute another target light-emitting unit in the group of target light-emitting units.

[0040] The second and third electrode layers are electrically connected and can be understood as a common electrode for the target light-emitting unit.

[0041] The overlapping of the orthographic projections of different target light-emitting units in the same group onto the substrate can be understood as the different target light-emitting units in the same group being stacked along a direction perpendicular to the substrate. In other words, there is a certain overlap between the opening regions of each target light-emitting unit in the same group. Thus, the actual area occupied by two target light-emitting units in the same group is less than the sum of the areas of the two target light-emitting units.

[0042] like Figure 1 and Figure 2 As shown, where, Figure 1 The first luminescent layer 114 and the second luminescent layer 119 are luminescent layers of different target luminescent units in the same group. For example... Figure 2 As shown, in an exemplary embodiment, the display substrate includes a red sub-pixel R, a green sub-pixel G, and a blue sub-pixel B. The first light-emitting layer 114 and the second light-emitting layer 119 can be light-emitting layers for different sub-pixels, respectively. The orthographic projections of the light-emitting units of different sub-pixels onto the substrate overlap.

[0043] In some embodiments, the orthographic projections of different target light-emitting units in the same group onto the substrate can completely overlap, while the orthographic projections of different target light-emitting units in the same group do not completely overlap, but only partially overlap.

[0044] In some embodiments, one target light-emitting unit corresponds to one sub-pixel. In some embodiments, the same group of target light-emitting units corresponds to sub-pixels of different colors. That is, the light-emitting colors of two stacked light-emitting units are different.

[0045] like Figure 2 As shown, in some embodiments, the first group of target light-emitting units includes a red sub-pixel R and a green sub-pixel G, the second group of target light-emitting units includes a green sub-pixel G and a blue sub-pixel B, and the third group of sub-pixels includes a red sub-pixel R and a blue sub-pixel B.

[0046] In some embodiments, the same group of target light-emitting units may correspond to the same pixel or to sub-pixels in different pixels.

[0047] like Figure 3 and Figure 4 As shown, in one exemplary embodiment, a pixel comprises three sub-pixels: red, green, and blue. These pixels can be arranged in different ways.

[0048] like Figure 3As shown, the three sub-pixels (R1, B1, and G1) of the first pixel are arranged sequentially, and the three sub-pixels (R2, B2, and G2) of the second pixel overlap with the three sub-pixels of the first pixel. In this way, the same group of target light-emitting units belong to different sub-pixels.

[0049] like Figure 4 As shown, the same group of target light-emitting units can correspond to the same pixel. Specifically, the red sub-pixel R1 of the first pixel overlaps with the green sub-pixel G1 of the first pixel, the blue sub-pixel B1 of the first pixel overlaps with the green sub-pixel G2 of the second pixel, and the red sub-pixel R2 of the second pixel overlaps with the blue sub-pixel B2 of the second pixel.

[0050] It should be understood that the above embodiments are for illustrative purposes only. In practice, different pixel and subpixel arrangements can be selected as needed, and the color of the subpixels is not limited to these.

[0051] In some embodiments, the pixel driving circuit includes a target pixel driving circuit, which drives a group of target light-emitting units to emit light.

[0052] In the technical solution of this embodiment, the same group of target light-emitting units are driven to emit light through the same target pixel driving circuit. This can be understood as one pixel driving circuit being used to drive multiple target light-emitting units to emit light. In this way, compared with the prior art, the number of required pixel driving circuits can be reduced.

[0053] This invention provides a display driving method applied to a display device including the above-described display substrate. In one embodiment, the method includes the following steps:

[0054] During the light emission stage, different target light emission units in the same group are controlled to emit light simultaneously or in a time-division manner.

[0055] In the technical solution of this embodiment, each target light-emitting unit in the same group can emit light simultaneously. In other words, the light-emitting periods of each target light-emitting unit in the same group overlap or coincide.

[0056] In the technical solution of this embodiment, the target pixel driving circuit includes at least two light emission control sub-circuits, and one light emission control sub-circuit is used to control the light emission of a target light emission unit.

[0057] In some embodiments, when controlling different target light-emitting units in the same group to emit light simultaneously, the method includes:

[0058] During the light emission period, the corresponding target light emission unit is controlled to emit light by the target light emission control sub-circuit in at least two light emission control sub-circuits, while the target light emission unit corresponding to the light emission control sub-circuit outside the target light emission control sub-circuit is in the off state.

[0059] In some embodiments, such as Figures 5 to 7 As shown, the target pixel driving circuit includes a first driving sub-circuit, a second driving sub-circuit, and a detection control sub-circuit.

[0060] The input terminal of the detection control sub-circuit is connected to the constant current signal terminal I0.

[0061] The input terminal of the first driving sub-circuit is connected to the output terminal of the detection control sub-circuit, and the first driving sub-circuit is connected to the first scan line G(n) and the first target light-emitting unit D1; the data input terminal of the second driving sub-circuit is connected to the output terminal of the detection control sub-circuit, and the second driving sub-circuit is also connected to the second scan line G(n-1) and the second target light-emitting unit D2.

[0062] like Figure 5 As shown, in one embodiment, the target pixel driving circuit includes two driving sub-circuits: a first driving sub-circuit and a second driving sub-circuit. The first driving sub-circuit includes a first switch T1, a second switch T2, and a first storage capacitor C1, and is used to control the first target light-emitting unit D1. The second driving sub-circuit includes a third switch T3, a fourth switch T4, and a second storage capacitor C2, and is used to control the first target light-emitting unit D2.

[0063] like Figure 5 As shown, the first control switch S1 is closed, and the two second control switches S2-1 and S2-2, as well as the detection control sub-circuit 500, can be integrated into the driver chip (source IC). In the technical solution of this embodiment, during the light emission period, the first control switch S1 is closed, and the two second control switches S2-1 and S2-2 are open. At this time, each light emission control sub-circuit can be understood as a 2T1C driver circuit, which can drive the first target light emission unit D1 and the second target light emission unit D2 to emit light respectively.

[0064] In some embodiments, the method further includes:

[0065] During the voltage threshold detection period, the first threshold voltage of the driving transistor of the first target light-emitting unit and the second threshold voltage of the driving transistor of the second target light-emitting unit are detected by the detection control sub-circuit.

[0066] Please also refer to Figures 5 to 7 During the voltage threshold detection period, the first control switch S1 is open, and the two second control switches S2-1 and S2-2 are closed.

[0067] At this time, the driving signals G(n-1), G(n)... are turned on row by row in sequence. At this time, the Data signal of all pixels is a fixed value. Taking the first light-emitting control sub-circuit as an example, the control terminal of the second switch T2 obtains a fixed value signal from the G(n) terminal.

[0068] At this point, two different constant current signals are provided through the constant current source I0, thereby obtaining two different voltage values. For example, the power supply of the constant current source can be set to 100nA and 900nA respectively. It should be understood that the larger the voltage difference between the two voltages, the more accurate the detection result will be.

[0069] For example, if the detection control sub-circuit 500 detects two voltages, Vs1 and Vs2, then the following can be obtained:

[0070]

[0071]

[0072] In the above formulas, W is the channel width of the driving transistor, L is the channel length of the driving transistor, Cox is the channel capacitance of the driving transistor, and μ is a preset coefficient. The ratio of formula (1) to formula (2) yields:

[0073]

[0074] During this process, all parameters related to the driving transistor are eliminated. The current values ​​of the two constant current sources are Ioled1 = 100nA and Ioled2 = 900nA, respectively. Therefore, the final formula is:

[0075]

[0076] The input data voltage Vg is known, and Vs1 and Vs2 are measured by the detection control circuit 500 during the two tests, from which the value of Vth can be obtained.

[0077] In one embodiment, the detection control sub-circuit 500 includes multiple resistors Re1 to Re3, amplifier D0, digital-to-analog converter module 501, and processor 502. The detection voltage of the detection terminal Vdect is amplified by amplifier D0 and then input to digital-to-analog converter module 502. After being converted into a digital signal, it is stored in memory under the control of processor 502.

[0078] In some embodiments, when controlling different target light-emitting units in the same group to emit light in a time-division manner, the method includes:

[0079] During the light-emitting period, the first target light-emitting unit is controlled to emit light by the first driving sub-circuit, and the second target light-emitting unit is controlled to emit light by the second driving sub-circuit.

[0080] In another embodiment, the target light-emitting units in the same group can also emit light in a time-sharing manner, that is, the light-emitting periods of the target light-emitting units in the same group do not overlap.

[0081] In some embodiments, the target pixel driving circuit includes at least two light-emitting control sub-circuits, each of which controls the light emission of a target light-emitting unit. In this embodiment, the target pixel driving circuit includes two light-emitting control sub-circuits as an example.

[0082] like Figure 8 As shown, in one embodiment, the target pixel driving circuit includes a first switch T1, a second switch T2, a third switch T3, a fourth switch T4, a fifth switch T5, a sixth switch T6, a seventh switch T7, a storage capacitor Cst, a first target light-emitting unit D1, and a second target light-emitting unit D2.

[0083] In this embodiment, the sixth light-emitting diode T6 serves as the first light-emitting control sub-circuit, and the seventh switch T7 serves as the second light-emitting control sub-circuit.

[0084] Please also refer to Figure 8 and 9 During the reset period T1, the scan control signal S(n), the light emission control signal EM, and the drive signal G(n) are at low levels. The seventh switch T7, the first switch T1, and the fourth switch T4 are turned on. At this time, the level at point a is the level Vss of the first voltage signal terminal VSS, and the level at point b is Vss.

[0085] During the voltage writing compensation period T2, the scan control signals S(n) and Gate(n) are low, the first switch T1 and the third switch T3 are turned on, and charging begins at point a. When the charge reaches Vdd + Vth, the second switch T2 is turned off. Here, Vdd is the level provided by the second voltage signal terminal VDD, and Vth is the threshold voltage of the driving transistor (second switch T2). At this time, the data voltage Vdata provided by the data line Data is written at point b.

[0086] During the light-emitting period T3, either the first light-emitting control signal EM1 or the second light-emitting control signal EM2 is at a low level, and correspondingly, either the fifth switch T5 or the sixth switch T6 is turned on. The voltage at point b changes from Vdata to Vss, and the voltage at point a changes from Vdd + Vth + Vdata - Vss.

[0087] During this process, if one of the first light-emitting control signal EM1 and the second light-emitting control signal EM2 is at a low level and the other is at a high level, then one of the fifth switch transistor T5 and the sixth switch transistor T6 will be turned on, and correspondingly, one of the first target light-emitting unit D1 and the second target light-emitting unit D2 will emit light.

[0088] For example, please refer to Figure 8 and Figure 9 If the first light-emitting control signal EM1 is low and the second light-emitting control signal EM2 is high, then the fifth switch T5 is turned on and the sixth switch T6 is turned off. In this way, the first target light-emitting unit D1 emits light, while the second target light-emitting unit D2 does not emit light. This achieves time-sharing light emission from different target light-emitting units within the same group.

[0089] This invention provides a display device comprising a display substrate according to any one of the above.

[0090] The display device of this embodiment includes all the technical solutions of the above-mentioned display substrate and can achieve the same or similar technical effects, which will not be repeated here.

[0091] The above description represents the preferred embodiments of the present invention. It should be noted that those skilled in the art can make various improvements and modifications without departing from the principles of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A display substrate, characterized by, The display substrate comprises a substrate, a pixel driving circuit on the substrate, and a light emitting unit which emits light under the driving of the pixel driving circuit, the light emitting unit comprises a plurality of groups of target light emitting units, the number of target light emitting units in each group of target light emitting units is at least two, and the orthographic projections of different target light emitting units in the same group on the substrate overlap. The pixel driving circuit comprises a target pixel driving circuit, and one target pixel driving circuit is used to drive a group of target light emitting units to emit light. The target pixel driving circuit comprises a first driving sub-circuit, a second driving sub-circuit, and a detection control sub-circuit. The input end of the detection control sub-circuit is connected with a constant current signal end. The input end of the first driving sub-circuit is connected with the output end of the detection control sub-circuit, the first driving sub-circuit is connected with a first scanning line and a first target light emitting unit. The data input end of the second driving sub-circuit is connected with the output end of the detection control sub-circuit, and the second driving sub-circuit is further connected with a second scanning line and a second target light emitting unit. Different target light emitting units in the same group correspond to sub-pixels of different colors respectively. The display substrate further comprises a first electrode layer, a first light emitting layer, a second electrode layer, a charge generation layer, a second light emitting layer, and a third electrode layer, the part of the first electrode layer connected with the first light emitting layer, the first light emitting layer, and the second electrode layer constitute one target light emitting unit in a group of target light emitting units, the charge generation layer, the second light emitting layer, and the third electrode layer constitute another target light emitting unit in the group of target light emitting units, and the orthographic projections of different target light emitting units in the same group on the substrate overlap. 2.The display substrate of claim 1, wherein, Different target light emitting units in the same group correspond to sub-pixels in different pixels respectively.

3. The display substrate according to claim 1 or 2, wherein The target pixel driving circuit comprises at least two light emitting control sub-circuits, and one light emitting control sub-circuit is used to control one target light emitting unit to emit light.

4. A display device, characterized by comprising: The display substrate comprises any one of claims 1 to 3.

5. A display driving method, characterized by, The method is applied to the display device of claim 4, and the method comprises the following steps: In the light emitting stage, different target light emitting units in the same group are controlled to emit light at the same time or at different times; In the case of controlling different target light emitting units in the same group to emit light at different times, the method comprises: In the light emitting period, the first target light emitting unit is controlled to emit light by the first driving sub-circuit, and the second target light emitting unit is controlled to emit light by the second driving sub-circuit; The method further comprises: in the voltage threshold detection period, the first threshold voltage of the driving transistor of the first target light emitting unit and the second threshold voltage of the driving transistor of the second target light emitting unit are detected by the detection control sub-circuit.

6. The method of claim 5, wherein, In the case of controlling different target light emitting units in the same group to emit light at the same time, the method comprises: In the light emitting period, the corresponding target light emitting unit is controlled to emit light by the target light emitting control sub-circuit in the at least two light emitting control sub-circuits, and the corresponding target light emitting unit is in an off state by the light emitting control sub-circuit other than the target light emitting control sub-circuit.

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