Array substrate, driving method, organic light-emitting display panel and display device
By sharing voltage control circuits among multiple pixel circuits, the array substrate design addresses the high PPI challenge in OLED displays, enhancing manufacturing efficiency and reducing pixel circuit area to achieve higher pixel density and improved image retention.
Patent Information
- Application Number
- JP2020571763
- Authority / Receiving Office
- JP · JP
- Patent Type
- Patents
- Current Assignee / Owner
- Priority Date
- 2018-10-18
- Filing Date
- 2019-10-14
- Publication Date
- 2026-01-30
- Estimated Expiration
- 2039-10-14
AI Technical Summary
Conventional OLED display panels face challenges in achieving high PPI due to the large area occupied by pixel circuits, which is exacerbated in micro-OLEDs and mini-OLEDs, limiting manufacturing precision and display performance.
The array substrate design includes pixel circuits in the display area coupled to light-emitting devices, with at least two pixel circuits sharing a voltage control circuit, and a simplified structure that reduces the area occupied by pixel circuits, allowing for higher pixel density by sharing voltage control circuits.
This design simplifies the pixel circuit structure, reduces the display area occupied by pixel circuits, enabling higher PPI organic light-emitting display panels and improves image retention by controlling voltage to prevent frame-to-frame interference.
Smart Images

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Abstract
Description
[Technical Field]
[0001] CROSS-REFERENCE TO RELATED APPLICATIONS This application claims priority from a Chinese patent application filed with the China Patent Office on October 18, 2018, bearing application number 201811215357.6 and entitled "Array substrate, driving method, organic light-emitting display panel and display device," the entire contents of which are incorporated herein by reference.
[0002] The present disclosure relates to the field of display technology, and more particularly to an array substrate, a driving method, an organic light-emitting display panel, and a display device. [Background technology]
[0003] Organic light-emitting diode (OLED) display panels are currently a focus of research in the field of flat panel displays. Compared with liquid crystal displays (LCDs), OLED displays have advantages such as low energy consumption, low production costs, self-luminance, wide viewing angles, and fast response times. However, conventional OLED display panels include multiple pixel units, each of which includes multiple subpixels. Each subpixel includes an OLED and a pixel circuit for driving the OLED. The pixel circuit typically includes multiple transistors and capacitors. Due to limited manufacturing precision, the pixel circuit occupies a large area within the subpixel, which is detrimental to achieving a high PPI OLED display panel. Particularly when OLEDs are implemented as micro-OLEDs or mini-OLEDs, the large subpixel area occupied by the pixel circuit has a significant impact on the high PPI OLED display panel. Summary of the Invention [Problem to be solved by the invention]
[0004] The embodiments of the present disclosure provide an array substrate, a driving method, an organic light-emitting display panel, and a display device that are advantageous in reducing the area occupied by pixel circuits and achieving a display panel with a high PPI. [Means for solving the problem]
[0005] An embodiment of the present disclosure includes: a plurality of light emitting devices located in a display area; a pixel circuit located in the display area, coupled to each of the light emitting devices, the pixel circuit including a drive transistor; and a plurality of voltage control circuits located in a non-display area, wherein at least two of the pixel circuits share one voltage control circuit, and in the pixel circuits, a first pole of each of the drive transistors is coupled to the shared voltage control circuit and a second pole of each of the drive transistors is coupled to a corresponding one of the light-emitting devices.
[0006] In an embodiment of the present disclosure, the array substrate may further include a plurality of pixel units located within the display area, and each of the pixel units may include a plurality of sub-pixels including one of the light-emitting devices and one of the pixel circuits.
[0007] In the embodiment of the present disclosure, the pixel circuits are arranged in a plurality of rows, and pixel circuits in at least two adjacent sub-pixels in the same row may share one of the voltage control circuits.
[0008] In an embodiment of the present disclosure, all pixel circuits in the same row may share one of the voltage control circuits.
[0009] In an embodiment of the present disclosure, the voltage control circuit may include a first switching transistor having a gate configured to receive the recovery control signal, a first pole configured to receive the initialization signal, and a second pole coupled to a first pole of a corresponding drive transistor.
[0010] The voltage control circuit further includes a second switching transistor, a gate of the second switching transistor configured to receive a light emission control signal, a first pole of the second switching transistor configured to receive the first power supply signal, and a second pole of the second switching transistor coupled to a first pole of the corresponding driving transistor.
[0011] In an embodiment of the present disclosure, the pixel circuit further includes a storage capacitor having a second terminal coupled to a ground terminal, the gate of the storage capacitor having the second terminal coupled to the ground terminal configured to receive a first gate scanning signal, the gate of the storage capacitor having the second terminal coupled to the ground terminal configured to be coupled to a first gate driving circuit of the storage capacitor, the first terminal of the storage capacitor being coupled to the ground terminal, and the third switching transistor having a first terminal configured to receive a data signal, the second terminal of the storage capacitor having the second terminal coupled to the ground terminal configured to be coupled to the gate of the driving transistor, and the first terminal of the third switching transistor being coupled to the gate of the driving transistor.
[0012] In an embodiment of the present disclosure, the pixel circuit may further include a fourth switching transistor, wherein the fourth switching transistor is different in type from the third switching transistor, a gate of the fourth switching transistor is configured to receive a second gate scanning signal and is coupled to a second gate driving circuit of the fourth switching transistor, a first pole of the fourth switching transistor is configured to receive the data signal, and a second pole is coupled to the gate of the driving transistor.
[0013] In an embodiment of the present disclosure, the pixel circuit may further include a fifth switching transistor, through which the second pole of the driving transistor is coupled to the corresponding light-emitting device, a gate of the fifth switching transistor is coupled to a reference signal terminal, a first pole of the fifth switching transistor is coupled to the second pole of the driving transistor, and the second pole of the fifth switching transistor is coupled to the corresponding light-emitting device.
[0014] In an embodiment of the present disclosure, the fifth switching transistor may be a P-type transistor, and the reference signal terminal may be a ground terminal.
[0015] In an embodiment of the present disclosure, the array substrate may further include a plurality of light emission control signal lines and a light emission control circuit electrically connected to each of the light emission control signal lines, and each of the light emission control signal lines may be electrically connected to the voltage control circuit to which one row of the pixel circuits is electrically connected, and configured to input the light emission control signal to the electrically connected voltage control circuit.
[0016] In an embodiment of the present disclosure, the light emission control circuit may include a plurality of cascaded light emission shift registers, and each of the light emission shift registers may be electrically connected to correspond to one of the light emission control signal lines.
[0017] In an embodiment of the present disclosure, the array substrate further includes one first power supply signal line electrically connected to all the voltage control circuits and configured to input the first power supply signal to each of the voltage control circuits; or The pixel circuit may further include a plurality of first power supply signal lines, and one of the light emission control signal lines may be electrically connected to the voltage control circuit to which one row of the pixel circuits is electrically connected, and may be configured to input the first power supply signal to the electrically connected voltage control circuit.
[0018] Correspondingly, an embodiment of the present disclosure further provides an organic light emitting display panel including an array substrate according to an embodiment of the present disclosure.
[0019] Correspondingly, an embodiment of the present disclosure further provides a display device including an organic light-emitting display panel according to an embodiment of the present disclosure.
[0020] Correspondingly, the embodiment of the present disclosure: controlling the voltage control circuit and the pixel circuit to drive a light-emitting device within a display period of one frame; The step of operating a row of light emitting devices includes: a reset step in which the voltage control circuit outputs an initialization signal to the first electrode of the driving transistor in response to the reset control signal to reset the corresponding light emitting device; a data writing step of outputting a data signal to the gate of the driving transistor; The present disclosure further provides a driving method for an array substrate according to an embodiment, including a light-emitting step in which the voltage control circuit outputs a first power supply signal to the first electrode of the driving transistor in response to a light-emitting control signal, thereby driving the light-emitting device to emit light.
[0021] In an embodiment of the present disclosure, after the light emitting stage, the step of driving the row of light emitting devices comprises: The voltage control circuit may further include a non-light emitting stage in which, in response to a light emitting control signal, the voltage control circuit disconnects a first power supply signal from a first electrode of the driving transistor and controls the corresponding pixel circuit to drive the connected light emitting device to stop emitting light.
[0022] In the embodiment of the present disclosure, within the display period of one frame, the non-light-emitting stages of driving the light-emitting devices of each row are turned on at the same time; or During the display period of one frame, the non-light emitting stages for driving the light emitting devices of each row may be sequentially turned on row by row.
[0023] In an embodiment of the present disclosure, after the light emitting stage, the step of driving the row of light emitting devices comprises: The light control method further includes a dimming step including at least one non-light-emitting step and at least one light-emitting step, and the non-light-emitting step and the light-emitting step are set alternately in sequence; In the non-light emitting stage, the voltage control circuit is responsive to the light emitting control signal to disconnect the first power supply signal from the first electrode of the driving transistor, and control the corresponding pixel circuit to drive the connected light emitting device to stop emitting light; In the light-emitting stage, the voltage control circuit may be configured to output a first power supply signal to a first electrode of the driving transistor in response to a light-emitting control signal, thereby controlling a corresponding pixel circuit to drive a connected light-emitting device to emit light.
[0024] In an embodiment of the present disclosure, within the display period of one frame, the dimming stages for driving the light-emitting devices of each row are turned on at the same time; During the display period of one frame, the dimming stages for driving the light emitting devices of each row may be sequentially turned on row by row. [Effects of the Invention]
[0025] The beneficial effects of the present disclosure are as follows:
[0009] The embodiments of the present disclosure provide an array substrate, a driving method, an organic light emitting display panel, and a display device, the array substrate including a plurality of light emitting devices in a display area and pixel circuits connected to each light emitting device, and a plurality of voltage control circuits in a non-display area, where at least two pixel circuits share one voltage control circuit, thereby simplifying the structure of each pixel circuit in the display area, reducing the area occupied by the pixel circuits in the display area, allowing more pixel circuits and light emitting devices to be installed in the display area, and achieving a high PPI organic light emitting display panel. Furthermore, the voltage control circuit is controlled by a reset control signal to output an initialization signal to a first electrode of a driving transistor to reset a corresponding light emitting device, thereby avoiding the voltage applied to the light emitting device during the emission of a previous frame from affecting the emission of the next frame and improving the phenomenon of image retention. [Brief explanation of the drawings]
[0026] [Figure 1] FIG. 2 is a structural schematic diagram of an example of an array substrate according to an embodiment of the present disclosure. [Figure 2] FIG. 10 is a structural schematic diagram of another array substrate according to an embodiment of the present disclosure. [Figure 3a] FIG. 10 is a structural schematic diagram of another array substrate according to an embodiment of the present disclosure. [Figure 3b]FIG. 10 is a structural schematic diagram of another array substrate according to an embodiment of the present disclosure. [Figure 4] FIG. 2 is a specific structural schematic diagram of an example of an array substrate according to an embodiment of the present disclosure. [Figure 5] FIG. 10 is a specific structural schematic diagram of another array substrate according to an embodiment of the present disclosure. [Figure 6] 1 is a flowchart of a driving method according to an embodiment of the present disclosure. [Figure 7] FIG. 2 is an example of a circuit timing diagram according to an embodiment of the present disclosure. [Figure 8] FIG. 10 is another circuit timing diagram according to an embodiment of the present disclosure. [Figure 9] FIG. 10 is another circuit timing diagram according to an embodiment of the present disclosure. [Figure 10] FIG. 10 is another circuit timing diagram according to an embodiment of the present disclosure. [Figure 11] FIG. 10 is another circuit timing diagram according to an embodiment of the present disclosure. [Figure 12] FIG. 10 is another circuit timing diagram according to an embodiment of the present disclosure. [Figure 13] FIG. 10 is another circuit timing diagram according to an embodiment of the present disclosure. DETAILED DESCRIPTION OF THE INVENTION
[0027] To clarify the objectives, technical solutions, and advantages of the present disclosure, specific embodiments of an array substrate, a driving method, an organic light-emitting display panel, and a display device according to the embodiments of the present disclosure will be described in detail below with reference to the drawings. It should be understood that the preferred embodiments described below are merely for the purpose of explaining and interpreting the disclosure, and are not intended to limit the present disclosure. Furthermore, unless inconsistent, the embodiments and features of the embodiments of the present disclosure may be combined with each other. Furthermore, the thickness and shape of each thin film layer in the drawings do not reflect the actual scale of the array substrate, but are merely for illustrative purposes of the contents of the present disclosure. Furthermore, throughout the text, the same or similar reference numerals refer to the same or similar components or components having the same or similar functions.
[0028] An embodiment of the present disclosure provides an array substrate, and as shown in FIG. 1, the array substrate includes: a plurality of light-emitting devices L located in a display area AA; Pixel circuits 10 are located in the display area AA, coupled to each light-emitting device L, specifically, each pixel circuit 10 is coupled to each light-emitting device L, and each pixel circuit 10 corresponds to each light-emitting device L in a one-to-one correspondence, and includes a driving transistor; and a plurality of voltage control circuits 20 located in a non-display area (an area of the array substrate other than the display area AA), wherein at least two pixel circuits 10 share one voltage control circuit 20, and the first poles of the drive transistors in the pixel circuits 10 are coupled to the shared voltage control circuit 20, and the second poles of the drive transistors are coupled to corresponding light-emitting devices L. The voltage control circuits 20 are configured to output an initialization signal Vinit to the first poles of the drive transistors in response to a restoration control signal RE to control and restore the corresponding light-emitting devices L, and to output a first power supply signal VDD to the first poles of the drive transistors in response to a light-emission control signal EM to drive the light-emitting devices L to emit light.
[0029] The array substrate according to the embodiment of the present disclosure includes a plurality of light-emitting devices in the display area and pixel circuits connected to each light-emitting device, and a plurality of voltage control circuits in the non-display area, where at least two pixel circuits share one voltage control circuit, thereby simplifying the structure of each pixel circuit in the display area, reducing the area occupied by the pixel circuits in the display area, allowing more pixel circuits and light-emitting devices to be installed in the display area, and achieving a high PPI organic light-emitting display panel. Furthermore, the voltage control circuit is controlled by the reset control signal to output an initialization signal to the first electrode of the driving transistor to control the corresponding light-emitting device to reset, thereby avoiding the voltage applied to the light-emitting device during the emission of the previous frame from affecting the emission of the next frame and improving the phenomenon of image retention.
[0030] In a specific implementation, in the embodiment of the present disclosure, as shown in FIG. 1 , the array substrate may further include a plurality of pixel units PX located within the display area AA, and each pixel unit PX includes a plurality of sub-pixels 40, each including one light emitting device L and one pixel circuit 10. Furthermore, the pixel unit PX may include three sub-pixels 40 of different colors, which may be red, green, and blue sub-pixels, respectively. Of course, the pixel unit may also include four, five, or more sub-pixels, which is designed and determined according to the actual application environment and will not be described here.
[0031] In a specific implementation, in the embodiment of the present disclosure, pixel circuits are arranged in multiple rows, and pixel circuits in at least two adjacent subpixels in the same row may share one voltage control circuit. In the pixel circuits 10 in one row, the first electrodes of the drive transistors are coupled to a shared voltage control circuit 20. Specifically, as shown in FIG. 1, all pixel circuits 10 in the same row may share one voltage control circuit 20. Alternatively, two, three, or more adjacent pixel circuits in the same row may share one voltage control circuit, which will not be described here. Sharing a voltage control circuit in this way can reduce the area occupied by pixel circuits in the display area.
[0032] 2, the array substrate may further include a plurality of light emission control signal lines SEM and a light emission control circuit 30 electrically connected to each light emission control signal line SEM, where each light emission control signal line SEM is electrically connected to a voltage control circuit electrically connected to one row of pixel circuits, and is configured to input a light emission control signal to the electrically connected voltage control circuit. Specifically, each light emission control signal line SEM is electrically connected to the gate of the second switching transistor M2 electrically connected to one row of pixel circuits in the display area AA.
[0033] 3a and 3b, the light emission control circuit 30 may include a plurality of cascaded light emission shift registers EOA, each of which is electrically connected to a corresponding light emission control signal line SEM. Specifically, the light emission input signal terminal of the first-stage light emission shift register EOA is configured to receive a frame light emission trigger signal, and the light emission input signal terminals of the remaining light emission shift registers EOA are electrically connected to the light emission output signal terminals of the adjacent preceding-stage light emission shift registers EOA, respectively, to achieve the function of inputting a light emission control signal to the light emission control signal line SEM. In actual application, the structure of the light emission shift register is the same as the conventional structure, and therefore will not be described in detail here.
[0034] 2 and 3a, in the embodiment of the present disclosure, the array substrate may further include a first power signal line SVDD electrically connected to all voltage control circuits and configured to input a first power signal to each voltage control circuit. Specifically, the first power signal line SVDD is electrically connected to the first electrodes of all second switching transistors M2. Furthermore, the first power signal line SVDD may be provided in the non-display area so as to further reduce the number of wirings provided in the display area AA and achieve a high PPI organic light-emitting display panel.
[0035] In a specific implementation, in an embodiment of the present disclosure, as shown in FIG. 3b, the array substrate may include a plurality of first power supply signal lines SVDD_m (1≦m≦M, m and M are each an integer, and M represents the total number of first power supply signal lines, M=4 in FIG. 3b), where one light emission control signal line SVDD_m is electrically connected to a voltage control circuit electrically connected to one row of pixel circuits, and is configured to input a first power supply signal to the electrically connected voltage control circuit. Specifically, one light emission control signal line SVDD_m is electrically connected to the first electrodes of all second switching transistors M2 in one row. Furthermore, all light emission control signal lines SVDD_m may be arranged in the non-display area, so as to further reduce the number of wirings arranged in the display area AA and achieve a high PPI organic light emitting display panel.
[0036] In a specific implementation, in the embodiment of the present disclosure, as shown in FIGS. 4 and 5, the driving transistor M0 may be an N-type transistor, and when a current flows from its first terminal S to its second terminal D, the first terminal S may function as its source and the second terminal D may function as its drain. When a current flows from its second terminal D to its first terminal S, the second terminal D may function as its source and the first terminal S may function as its drain. Furthermore, the light-emitting device L may include an OLED. Thus, the positive electrode of the OLED is electrically connected to the second terminal D of the driving transistor M0, and the negative electrode of the OLED is electrically connected to the second power terminal VSS. The voltage of the second power terminal VSS is generally a negative voltage or a ground voltage V. GND (generally 0V), and the voltage of the initialization signal is also the ground voltage V GND It may be set as 、 Here, the OLED may be configured as a Micro-OLED or a Mini-OLED, which is more advantageous in achieving a high PPI organic light-emitting display panel.
[0037] In a specific implementation, the voltage control circuit may include a first switching transistor having a gate configured to receive the return control signal, a first pole configured to receive the initialization signal, and a second pole coupled to the first pole of the corresponding drive transistor. Specifically, the voltage control circuit may further include a second switching transistor having a gate configured to receive the light-emitting control signal, a first pole configured to receive the first power signal, and a second pole coupled to the first pole of the corresponding drive transistor. The case where the voltage control circuit includes the first switching transistor and the second switching transistor will be described in detail below. As shown in FIGS. 4 and 5 (taking two pixel circuits in one row as an example), the voltage control circuit 20 may include a first switching transistor M1 and a second switching transistor M2, where the gate of the first switching transistor M1 is configured to receive the return control signal RE, the first pole of the first switching transistor M1 is configured to receive the initialization signal Vinit, and the second pole of the first switching transistor M1 is coupled to the first pole S of the corresponding drive transistor MO. The gate of the second switching transistor M2 is configured to receive the light-emitting control signal EM, the first pole of the second switching transistor M2 is configured to receive the first power supply signal VDD, and the second pole of the second switching transistor M2 is coupled to the first pole S of the corresponding driving transistor M0.
[0038] In a specific implementation, as shown in Figures 4 and 5, the first switching transistor M1 and the second switching transistor M2 may be different types. For example, the first switching transistor M1 is an N-type transistor and the second switching transistor M2 is a P-type transistor. Alternatively, the first switching transistor M1 is a P-type transistor and the second switching transistor M2 is an N-type transistor. Of course, the first switching transistor M1 and the second switching transistor M2 may be the same type. In actual applications, the types of the first and second switching transistors are designed according to the actual application environment, so there are no limitations here.
[0039] 4 and 5, the pixel circuit 10 may further include a third switching transistor M3 and a storage capacitor Cst, where the gate of the third switching transistor M3 is configured to receive a first gate scanning signal S1 and be coupled to the first gate driving circuit, the first pole of the third switching transistor M3 is configured to receive a data signal DA, and the second pole of the third switching transistor M3 is coupled to the gate G of the driving transistor M0. The first terminal of the storage capacitor Cst is coupled to the gate G of the driving transistor M0, and the second terminal of the storage capacitor Cst is coupled to the ground terminal GND.
[0040] 4 and 5, the pixel circuit 10 may further include a fourth switching transistor M4, where the gate of the fourth switching transistor M4 is configured to receive a second gate scanning signal S2 and be coupled to the second gate driving circuit, the first pole of the fourth switching transistor M4 is configured to receive a data signal DA, and the second pole of the fourth switching transistor M4 is coupled to the gate G of the driving transistor MO. Furthermore, the fourth switching transistor M4 and the third switching transistor M3 are of different types. For example, the third switching transistor M3 is an N-type transistor and the fourth switching transistor M4 is a P-type transistor, or the third switching transistor M3 is a P-type transistor and the fourth switching transistor M4 is an N-type transistor.
[0041] 5 , the pixel circuit 10 may further include a fifth switching transistor M5, and the second pole D of the driving transistor M0 is coupled to the corresponding light-emitting device L through the fifth switching transistor M5. Furthermore, the gate of the fifth switching transistor M5 is coupled to the reference signal terminal, the first pole of the fifth switching transistor M5 is coupled to the second pole D of the driving transistor M0, and the second pole of the fifth switching transistor M5 is coupled to the corresponding light-emitting device L. Furthermore, the fifth switching transistor M5 may be a P-type transistor, and the reference signal terminal may be set to the ground terminal GND.
[0042] Furthermore, in a specific implementation, the P-type transistor is turned off under the influence of a high-level signal and turned on under the influence of a low-level signal, and the N-type transistor is turned on under the influence of a high-level signal and turned off under the influence of a low-level signal.
[0043] The switching transistor may be a thin film transistor (TFT) or a metal oxide semiconductor field effect transistor (MOS), and is not limited thereto. In a specific implementation, the first pole of the switching transistor functions as its source and the second pole as its drain, or the second pole functions as its source and the first pole as its drain, and is not limited thereto.
[0044] Based on the same inventive concept, an embodiment of the present disclosure further provides a method for driving an array substrate according to an embodiment of the present disclosure, including controlling a voltage control circuit and a pixel circuit to drive a light-emitting device within a display period of one frame.
[0045] In a specific implementation, as shown in FIG. 6, the step of driving a row of light emitting devices may include S601 to S603. S601, reset stage: the voltage control circuit outputs an initialization signal to the first electrode of the driving transistor in response to the reset control signal, and controls the corresponding light emitting device to reset. S602, a data writing step, outputs a data signal to the gate of the driving transistor. S603, light emitting step: the voltage control circuit outputs a first power supply signal to the first electrode of the driving transistor in response to the light emitting control signal, so as to drive the light emitting device to emit light.
[0046] Hereinafter, a method for driving a row of light emitting devices will be described with reference to circuit timing diagrams, taking the structures of the array substrates shown in Figures 4 and 5 as examples. In the following description, 1 represents a high-level signal and 0 represents a low-level signal. Note that 1 and 0 are theoretical levels, and are only intended to facilitate a better understanding of the specific operating process of the embodiments of the present disclosure, and are not the levels applied to the gates of each switching transistor in actual implementation.
[0047] Example 1 4, M1 is an N-type transistor, M2 is a P-type transistor, M3 is an N-type transistor, and M4 is a P-type transistor, and the corresponding circuit timing diagram is shown in FIG. 7. The steps of driving a row of light-emitting devices may include a reset stage T1, a data writing stage T2, and a light-emitting stage T3.
[0048] In the reset stage T1, S1=0, S2=1, RE=1, EM=1.
[0049] Since EM=1, the second switching transistor M2 is turned off. Since S1=0, the third switching transistor M3 is turned off. Since S2=1, the fourth switching transistor M4 is turned off. Since RE=1, the first switching transistor M1 is turned on and supplies the initialization signal Vinit to the first pole S of the driving transistor M0. Note that when the previous frame is displayed, if the gate G of the driving transistor M0 stores a high grayscale data signal (i.e., indicates a high grayscale) through the storage capacitor Cst, the voltages of the first pole S and second pole D of the driving transistor M0 and the positive pole of the light-emitting device L are all equal to the ground voltage V GND When the previous frame is displayed, if the gate G of the driving transistor M0 stores a low gray scale data signal (i.e., indicates a low gray scale) through the storage capacitor Cst, the voltage of the first electrode S of the driving transistor M0 is reset to the ground voltage V GND and a current flows from the second pole D of the driving transistor M0 to its first pole S, thus causing the voltage between the second pole D and the positive pole of the light-emitting device L to rise to V GND -V th where V th denotes the threshold voltage of the driving transistor M0. In this way, the voltage applied to the light emitting device during the emission of the previous frame is prevented from affecting the emission of the next frame, and the phenomenon of image retention is improved.
[0050] In the data writing stage T1, S1=1, S2=0, RE=0, and EM=1.
[0051] Since EM=1, the second switching transistor M2 is turned off. Since RE=0, the first switching transistor M1 is turned off. Since S1=1, the third switching transistor M3 is turned on. Since S2=0, the fourth switching transistor M4 is turned on. The third switching transistor M3 and the fourth switching transistor M4 that are turned on supply the data signal DA to the gate G of the driving transistor M0, and connect the gate G of the driving transistor M0 to the voltage V of the data signal. DAand stored in the storage capacitor Cst. When the voltage of the data signal DA is a voltage corresponding to a high gray scale, the data signal DA is transmitted to the gate G of the driving transistor M0 by turning on the fourth switching transistor M4 of P type, so that the voltage of the avoidance data signal DA becomes equal to or higher than the threshold voltage V of the third switching transistor M3 of N type. th(M3) When the voltage of the data signal DA corresponds to a low gray scale, the data signal DA is transmitted to the gate G of the driving transistor M0 by turning on the third switching transistor M3 of N type, so that the voltage of the data signal DA is lower than the threshold voltage V of the fourth switching transistor M4 of P type. th(M4) In this way, the range of the voltage input to the gate G of the driving transistor M0 can be widened.
[0052] In the light emission stage T3, S1=0, S2=1, RE=0, and EM=0.
[0053] Since RE=0, the first switching transistor M1 is turned off. Since S1=0, the third switching transistor M3 is turned off. Since S2=1, the fourth switching transistor M4 is turned off. Since EM=1, the second switching transistor M2 is turned on, and the first power supply signal VDD is supplied to the first pole S of the driving transistor M0, and the voltage of the first pole S is set to the voltage V of the first power supply signal VDD. dd As can be seen from the current characteristics, the operating current I that flows through the driving transistor M0 and is configured to drive the light emitting device L to emit light is expressed by the formula: TIFF0007808928000001.tif767 (where V Drepresents the voltage at the second pole D of the driving transistor M0, and K is a structural parameter whose value is stable in the same structure and can be treated as a constant. ) is satisfied. In this way, the operating current I flows from the first power supply signal VDD through the second switching transistor M2 and the driving transistor M0 to the light emitting device L, driving the light emitting device L to emit light. Note that the voltage V at the second pole D of the driving transistor M0 D is an abbreviation for V DA -V th However, in reality, V D <V DA -V th In this way, by controlling the voltage of the gate G of the drive transistor M0, V D By varying the voltage at the electrode of the light emitting device L, the voltage difference between the electrodes of the light emitting device L can be varied, which in turn varies the light emission of the light emitting device L.
[0054] Example 2 The structural schematic diagram of the array substrate corresponding to this embodiment is shown in Figure 4, which is a modification of the embodiment of Example 1. Hereinafter, only the differences between this embodiment and Example 1 will be described, and the same parts will not be described in detail. In a specific implementation, as shown in Figure 8, after the light-emitting stage T3, the step of driving the light-emitting devices in one row may further include a non-light-emitting stage T4, in which the voltage control circuit disconnects the first power supply signal from the first electrode of the driving transistor in response to the light-emitting control signal EM, and controls the corresponding pixel circuit to drive the connected light-emitting device to stop emitting light.
[0055] Specifically, the corresponding circuit timing diagram is shown in Figure 8. The steps of driving one row of light-emitting devices may include a reset stage T1, a data writing stage T2, a light-emitting stage T3 and a non-light-emitting stage T4. Here, the reset stage T1, the data writing stage T2 and the light-emitting stage T3 can be referred to in Example 1, so they will not be described in detail here.
[0056] In the non-light-emitting stage T4, S1=0, S2=1, RE=0, and EM=1. Because RE=0, the first switching transistor M1 is off. Because S1=0, the third switching transistor M3 is off. Because S2=1, the fourth switching transistor M4 is off. Because EM=0, the second switching transistor M2 is off. In this way, the first power supply signal VDD no longer flows to the light-emitting device L via the second switching transistor M2 and the driving transistor M0, driving the light-emitting device L to stop emitting light. In this way, the voltage applied to the positive electrode of the light-emitting device L during the emission of the previous frame is further prevented from affecting the emission of the next frame, and the phenomenon of image retention is improved.
[0057] Example 3 In a specific implementation, as shown in FIG. 9, within a display period F of one frame (ie, Frame), the non-light-emitting stage T4 for driving the light-emitting devices of each row is turned on at the same time t0.
[0058] Specifically, an array substrate generally includes K rows of pixel units (K is a positive integer). G_k (1≦k≦K and an integer) represents signals for driving pixel circuits in the kth row of pixel units. During a display period (Frame) of one frame, the pixel circuits are driven row by row. After the light-emitting devices in the pixel units from the first row to the last row are driven to emit light, the light-emitting devices in the pixel units in each row are controlled to simultaneously stop emitting light. For example, if the display period (Frame) of one frame is 11.1 ms, the non-light-emitting stage (T4) can be 2 ms, and the remaining 9.1 ms can be the time for driving the pixel circuits in the pixel units from the first row to the last row to emit light.
[0059] Example 4 10, during one frame display period Frame, the non-light-emitting stages T4 for driving the light-emitting devices in each row are sequentially turned on row by row. During one frame display period Frame, the pixel circuits in the pixel units in the first row to the last row are sequentially driven in a row-by-row manner.
[0060] Specifically, after the light-emitting devices in the pixel units in the first row are driven to emit light, a non-light-emitting phase T4 begins at time t_1, during which the second switching transistors electrically connected to the pixel circuits in the first row are controlled to turn off, thereby controlling the light-emitting devices in the pixel units in the first row to stop emitting light. After the light-emitting devices in the pixel units in the second row are driven to emit light, a non-light-emitting phase T4 begins at time t_2, during which the second switching transistors electrically connected to the pixel circuits in the second row are controlled to turn off, thereby controlling the light-emitting devices in the pixel units in the second row to stop emitting light. After the light-emitting devices in the pixel units in the Kth row are driven to emit light, a non-light-emitting phase T4 begins at time t_K, during which the second switching transistors electrically connected to the pixel circuits in the Kth row are controlled to turn off, thereby controlling the light-emitting devices in the pixel units in the Kth row to stop emitting light. The rest is similar and will not be described in detail here.
[0061] Example 5 The structural schematic diagram of the array substrate corresponding to this embodiment is shown in Figure 4, which is a modification of the embodiment of Example 1. Below, only the differences between this embodiment and Example 1 will be described, and the same parts will not be described in detail here.
[0062] In a specific implementation, as shown in FIG. 11 , the step of driving one row of light-emitting devices after the light-emitting step T3 may further include a dimming step TS. The dimming step TS may include at least one non-light-emitting step TS1_x (1≦x≦X, where x and X are both positive numbers, and X represents the total number of non-light-emitting steps in the dimming step; in FIG. 11 , X=2) and at least one light-emitting step TS2_y (1≦y≦Y, where y and Y are both positive numbers, and Y represents the total number of light-emitting steps in the dimming step; in FIG. 11 , Y=2), where the non-light-emitting steps TS1_x and the light-emitting step TS2_y are set alternately. Here, X may be set to 1, 2, 3, etc., and Y may be set to 1, 2, 3, etc. However, in actual applications, the brightness requirements of the light-emitting devices vary depending on the application environment. Therefore, the number of non-light-emitting steps and light-emitting steps in the dimming step may be specifically designed and determined according to the actual application environment and is not limited herein.
[0063] Specifically, in the non-light-emitting stage TS1_x, the voltage control circuit responds to the light-emitting control signal by disconnecting the first power supply signal from the first electrode of the driving transistor and controlling the corresponding pixel circuit to drive the connected light-emitting device to stop emitting light.
[0064] In the light-emitting stage TS2_y, the voltage control circuit outputs a first power supply signal to the first electrode of the driving transistor in response to the light-emitting control signal, thereby controlling the corresponding pixel circuit to drive the connected light-emitting device to emit light. By setting the dimming stage in this way, the brightness of the light-emitting device can be effectively controlled.
[0065] 11, the dimming stages TS may include a non-light-emitting stage TS1_1, a light-emitting stage TS2_1, a non-light-emitting stage TS1_2, and a light-emitting stage TS2_2, which are set sequentially. Alternatively, the dimming stages may include a non-light-emitting stage, a light-emitting stage, and a non-light-emitting stage, which are set sequentially. This is not limited here.
[0066] Hereinafter, the operation process of the dimming stage TS will be described with reference to the circuit timing diagram of FIG. 11 and FIG. 4 as an example. In the non-light-emitting stage TS1_1, S1=0, S2=1, RE=0, and EM=1. Because RE=0, the first switching transistor M1 is off. Because S1=0, the third switching transistor M3 is off. Because S2=1, the fourth switching transistor M4 is off. Because EM=0, the second switching transistor M2 is off. In this way, the first power signal no longer flows to the light-emitting device L via the second switching transistor M2 and the driving transistor M0, driving the light-emitting device L to stop emitting light.
[0067] In the light-emitting stage TS2_1, S1=0, S2=1, RE=0, and EM=0. Because RE=0, the first switching transistor M1 is turned off. Because S1=0, the third switching transistor M3 is turned off. Because S2=1, the fourth switching transistor M4 is turned off. Because EM=1, the second switching transistor M2 is turned on and supplies the first power supply signal VDD to the first electrode S of the driving transistor M0. As a result, the operating current I flows from the first power supply signal VDD through the second switching transistor M2 and the driving transistor M0 to the light-emitting device L, driving the light-emitting device L to emit light.
[0068] In the non-light-emitting stage TS1_2, S1=0, S2=1, RE=0, and EM=1. Because RE=0, the first switching transistor M1 is turned off. Because S1=0, the third switching transistor M3 is turned off. Because S2=1, the fourth switching transistor M4 is turned off. Because EM=0, the second switching transistor M2 is turned off. In this way, the first power signal no longer flows to the light-emitting device L via the second switching transistor M2 and the driving transistor M0, driving the light-emitting device L to stop emitting light.
[0069] In the light-emitting stage TS2_2, S1=0, S2=1, RE=0, and EM=0. Because RE=0, the first switching transistor M1 is turned off. Because S1=0, the third switching transistor M3 is turned off. Because S2=1, the fourth switching transistor M4 is turned off. Because EM=1, the second switching transistor M2 is turned on and supplies the first power supply signal VDD to the first electrode S of the driving transistor M0. As a result, the operating current I flows from the first power supply signal VDD through the second switching transistor M2 and the driving transistor M0 to the light-emitting device L, driving the light-emitting device L to emit light.
[0070] Example 6 In a specific implementation, as shown in FIG. 12, within one frame display period Frame, the dimming stages TS for driving the light emitting devices of each row are turned on at the same time ts0.
[0071] Specifically, within one frame display period Frame, the pixel circuits are operated and driven one row at a time, and after the light-emitting devices in the pixel units from the first row to the last row are driven to emit light, the light-emitting devices in the pixel units of each row are controlled to simultaneously enter the dimming stage TS at time ts0.
[0072] Example 7 In specific implementation, as shown in FIG. 13, during one frame display period Frame, the dimming stages TS for driving the light emitting devices of each row are sequentially turned on row by row.
[0073] Specifically, during one frame display period (Frame), pixel circuits in the pixel units in the first row to the last row are sequentially driven row by row. Specifically, after the light-emitting devices in the pixel units in the first row are driven to emit light, the dimming stage TS begins at time ts_1. After the light-emitting devices in the pixel units in the second row are driven to emit light, the dimming stage TS begins at time ts_2. After the light-emitting devices in the pixel units in the Kth row are driven to emit light, the dimming stage TS begins at time t_K. The rest is similar and will not be described in detail here.
[0074] Example 8 5, compared to FIG. 4, a P-type fifth switching transistor M5 is provided only between the second electrode D of the driving transistor M0 and the positive electrode of the light-emitting device L. This fifth switching transistor M0 can function as a contrast clamper. Specifically, when the voltage of the data signal DA is a voltage corresponding to a high gray scale (for example, a high voltage), that is, when a high gray scale screen is displayed, the gate of the fifth switching transistor M5 is connected to the ground terminal GND, so that the fifth switching transistor M5 is controlled by the voltage of the ground terminal GND and the voltage of the second electrode D of the driving transistor M0 to be turned on, and V is applied to the positive electrode of the light-emitting device L. DA -V this applied, and thus the maximum brightness of the light-emitting device L is not affected. When the voltage of the data signal DA is a voltage corresponding to a low gray scale (e.g., a low voltage), that is, when a low gray scale screen is displayed, the gate of the fifth switching transistor M5 is connected to the ground terminal GND, so the voltage of the ground terminal GND and the voltage of the second terminal D of the driving transistor M0 are insufficient to control the fifth switching transistor M5 to be turned on. As a result, the current flowing through the fifth switching transistor M5 is very small, which corresponds to the second terminal D of the driving transistor M0 and the light-emitting device L being open-circuited. Thus, the brightness of the light-emitting device L is at a very low level. Therefore, as can be seen from the contrast equation, the contrast of the light-emitting device L is at its lowest in this mode.
[0075] Furthermore, the operation processes of other stages of the array substrate structure shown in FIG. 5 can be referred to Examples 1 to 7, respectively, and will not be described in detail here.
[0076] Based on the concept of the same disclosure, an embodiment of the present disclosure further provides an organic light-emitting display panel including an array substrate according to an embodiment of the present disclosure. Since the principle by which this organic light-emitting display panel solves problems is similar to that of the aforementioned array substrate, the implementation of this organic light-emitting display panel can refer to the implementation of the aforementioned array substrate, and the overlapping parts will not be described in detail here.
[0077] Based on the concept of the same disclosure, an embodiment of the present disclosure further provides a display device including the organic light-emitting display panel according to the embodiment of the present disclosure. The display device may be any product or component having a display function, such as a mobile phone, tablet, television, display, laptop, digital photo frame, or navigation device. All other components essential to the display device should be included based on the knowledge of those skilled in the art and will not be described in detail herein, nor should they be considered limitations of the present disclosure. For implementation of this display device, reference can be made to the embodiment of the organic light-emitting display panel, and overlapping parts will not be described in detail herein.
[0078] The embodiments of the present disclosure provide an array substrate, a driving method, an organic light emitting display panel, and a display device, the array substrate including a plurality of light emitting devices in a display area and pixel circuits connected to each light emitting device, and a plurality of voltage control circuits in a non-display area, where at least two pixel circuits in each row share one voltage control circuit, thereby simplifying the structure of each pixel circuit in the display area, reducing the area occupied by the pixel circuits in the display area, allowing more pixel circuits and light emitting devices to be installed in the display area, and achieving a high PPI organic light emitting display panel. Furthermore, the voltage control circuit is controlled by a reset control signal to output an initialization signal to a first electrode of a driving transistor to reset a corresponding light emitting device, thereby preventing the voltage applied to the light emitting device during the emission of the previous frame from affecting the emission of the next frame and improving the phenomenon of image retention.
[0079] Of course, those skilled in the art can make various changes and modifications to the present disclosure without departing from the spirit and scope of the present disclosure, and thus, if these modifications and modifications of the present disclosure fall within the scope of the claims of the present disclosure and the equivalent technologies, the present disclosure is intended to include these modifications and modifications.
Claims
1. a plurality of light emitting devices located in a display area; a pixel circuit located in the display area, coupled to each of the light emitting devices, the pixel circuit including a drive transistor; a plurality of voltage control circuits located in a non-display area, wherein at least two of the pixel circuits share one voltage control circuit, and in the pixel circuits, a first pole of each of the drive transistors is coupled to the shared voltage control circuit and a second pole of each of the drive transistors is coupled to a corresponding one of the light-emitting devices; the voltage control circuit includes a first switching transistor having a gate configured to receive a return control signal, a first pole configured to receive an initialization signal, and a second pole coupled to a first pole of the corresponding driving transistor; the voltage control circuit further includes a second switching transistor having a gate configured to receive a light emission control signal, a first pole configured to receive a first power supply signal, and a second pole coupled to the first pole of the corresponding driving transistor; the first switching transistor is an N-type transistor, and the second switching transistor is a P-type transistor; the pixel circuit further includes a fifth switching transistor, the fifth switching transistor having a gate coupled to a reference signal terminal, a first pole coupled to the second pole of the driving transistor, and a second pole coupled to the corresponding light-emitting device; the fifth switching transistor is a P-type transistor, and the reference signal terminal is a ground terminal;
2. The array substrate according to claim 1 , further comprising a plurality of pixel units located in the display area, each of the pixel units including a plurality of sub-pixels including one of the light-emitting devices and one of the pixel circuits.
3. 3. The array substrate according to claim 2, wherein the pixel circuits are arranged in a plurality of rows, and the pixel circuits in at least two adjacent sub-pixels in the same row share one of the voltage control circuits.
4. 4. The array substrate according to claim 3, wherein all the pixel circuits in the same row share one of the voltage control circuits.
5. 5. The array substrate of claim 1, wherein the pixel circuit further includes: a third switching transistor having a gate configured to receive a first gate scanning signal and coupled to a first gate driving circuit, a first pole configured to receive a data signal, and a second pole coupled to the gate of the driving transistor; and a storage capacitor having a first end coupled to the gate of the driving transistor and a second end coupled to a ground terminal.
6. 6. The array substrate of claim 5, wherein the pixel circuit further includes a fourth switching transistor different in type from the third switching transistor, the fourth switching transistor having a gate configured to receive a second gate scanning signal and coupled to a second gate driving circuit, a first pole configured to receive the data signal, and a second pole coupled to the gate of the driving transistor.
7. 5. The array substrate according to claim 1, further comprising a plurality of light emission control signal lines and a light emission control circuit electrically connected to each of the light emission control signal lines, wherein one of the light emission control signal lines is electrically connected to the voltage control circuit electrically connected to one row of the pixel circuits, and is configured to input a light emission control signal to the electrically connected voltage control circuit.
8. 8. The array substrate according to claim 7, wherein the light emission control circuit includes a plurality of cascaded light emission shift registers, each of which is electrically connected to one of the light emission control signal lines.
9. 8. The array substrate according to claim 7, further comprising one first power supply signal line electrically connected to all of said voltage control circuits and configured to input said first power supply signal to each of said voltage control circuits.
10. 8. The array substrate of claim 7, further comprising a plurality of first power supply signal lines, wherein one of the light emission control signal lines is electrically connected to the voltage control circuit electrically connected to one row of the pixel circuits, and is configured to input the first power supply signal to the electrically connected voltage control circuit.
11. An organic light-emitting display panel comprising the array substrate according to any one of claims 1 to 10.
12. A display device comprising the organic light-emitting display panel according to claim 11.
13. A driving method for an array substrate according to any one of claims 1 to 10, controlling the voltage control circuit and the pixel circuit to drive a light-emitting device within a display period of one frame; The step of driving a row of light emitting devices includes: a reset step in which the voltage control circuit outputs an initialization signal to the first electrode of the driving transistor in response to the reset control signal to reset the corresponding light emitting device; a data writing step of outputting a data signal to the gate of the driving transistor; a light emitting step in which the voltage control circuit outputs a first power supply signal to the first electrode of the driving transistor in response to a light emitting control signal to drive the light emitting device to emit light.
14. After the light emitting stage, the step of driving the row of light emitting devices comprises:
14. The driving method of claim 13, further comprising a non-light emitting step in which the voltage control circuit disconnects a first power supply signal from a first electrode of the driving transistor in response to a light emitting control signal, and controls the corresponding pixel circuit to drive the connected light emitting device to stop emitting light.
15. The driving method according to claim 14 , wherein the non-light-emitting stages of driving the light-emitting devices of each row are turned on at the same time within the display period of one frame.
16. The driving method according to claim 14 , wherein the non-light-emitting stages for driving the light-emitting devices of each row are sequentially turned on row by row within the display period of one frame.
17. After the light emitting stage, the step of driving the row of light emitting devices comprises: The light control method further includes a dimming step including at least one non-light-emitting step and at least one light-emitting step, and the non-light-emitting step and the light-emitting step are set alternately in sequence; In the non-light emitting stage, the voltage control circuit is responsive to the light emitting control signal to disconnect the first power supply signal from the first electrode of the driving transistor, and control the corresponding pixel circuit to drive the connected light emitting device to stop emitting light; 14. The driving method of claim 13, wherein, in the light emitting stage, the voltage control circuit outputs a first power supply signal to a first electrode of the driving transistor in response to a light emitting control signal, thereby controlling a corresponding pixel circuit to drive a connected light emitting device to emit light.
18. The driving method according to claim 15, wherein within the display period of one frame, the dimming steps for driving the light-emitting devices of each row are turned on at the same time.
19. The driving method according to claim 17 , wherein, within the display period of one frame, the dimming stages for driving the light emitting devices of each row are sequentially turned on row by row.
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