CN111785215B

CN111785215B - Pixel circuit compensation method and driving method, compensation device and display device

Info

Publication number: CN111785215B
Application number: CN201910272485.2A
Authority: CN
Inventors: 孟松
Original assignee: BOE Technology Group Co Ltd; Hefei Xinsheng Optoelectronics Technology Co Ltd
Current assignee: BOE Technology Group Co Ltd; Hefei Xinsheng Optoelectronics Technology Co Ltd
Priority date: 2019-04-04
Filing date: 2019-04-04
Publication date: 2022-04-22
Anticipated expiration: 2039-04-04
Also published as: CN111785215A; WO2020200205A1

Abstract

A compensation method and a driving method of a pixel circuit, a compensation device and a display device are provided, wherein the compensation method comprises the following steps: controlling the drive circuit to be conducted to charge the sensing signal line, and acquiring the voltage of a control end of the drive circuit as a first compensation data voltage under the condition that a first sensing voltage on the sensing signal line is equal to a first pre-stored sensing voltage; and controlling the drive circuit to be conducted to charge the sensing signal line, and acquiring the voltage of the control end of the drive circuit as a second compensation data voltage under the condition that the second sensing voltage on the sensing signal line is equal to a second pre-stored sensing voltage. The first pre-stored sensing voltage corresponds to a first initial optical compensation parameter written into the control terminal of the driving circuit under the condition that the light emitting element displays the first brightness, and the second pre-stored sensing voltage corresponds to a second initial optical compensation parameter written into the control terminal of the driving circuit under the condition that the light emitting element displays the second brightness.

Description

Pixel circuit compensation method and driving method, compensation device and display device

Technical Field

The embodiment of the disclosure relates to a compensation method and a driving method of a pixel circuit, a compensation device and a display device.

Background

Compared with the conventional liquid crystal display panel, an Organic Light-Emitting Diode (OLED) display panel has the advantages of faster response speed, higher contrast ratio, wider viewing angle, lower power consumption, and the like, and has been increasingly applied to high-performance display.

The pixel circuits in the OLED display panel generally adopt a Matrix driving method, and the driving method of the pixel circuits is divided into Active Matrix (AM) driving and Passive Matrix (PM) driving according to whether a switch element is introduced into each pixel unit. Although the PMOLED has a simple process and a low cost, the PMOLED cannot meet the requirements of high-resolution large-size display due to the defects of cross-talk, high power consumption, low service life and the like. In contrast, the AMOLED integrates a set of thin film transistors and a storage capacitor in a pixel circuit of each pixel unit, and the current flowing through the OLED is controlled by driving and controlling the set of thin film transistors and the storage capacitor, so that the OLED emits light as required. Compared with PMOLED, the AMOLED has the advantages of small driving current, low power consumption and longer service life, and can meet the large-size display requirements of high resolution and multi-gray scale. Meanwhile, the AMOLED has obvious advantages in the aspects of visual angle, color reduction, power consumption, response time and the like, and is suitable for display devices with high information content and high resolution.

Disclosure of Invention

At least one embodiment of the present disclosure provides a compensation method of a pixel circuit, wherein the pixel circuit includes a driving circuit including a control terminal and a first terminal, the first terminal of the driving circuit being configured to be electrically connected to a sensing signal line and a light emitting element, the compensation method including: controlling the drive circuit to be conducted to charge the sensing signal line, and acquiring the voltage of a control end of the drive circuit as a first compensation data voltage under the condition that a first sensing voltage on the sensing signal line is equal to a first pre-stored sensing voltage; controlling the drive circuit to be conducted to charge the sensing signal line, and acquiring the voltage of the control end of the drive circuit as a second compensation data voltage under the condition that a second sensing voltage on the sensing signal line is equal to a second pre-stored sensing voltage; wherein the first compensation data voltage and the second compensation data voltage are used for a display compensation operation of the pixel circuit, the first pre-stored sensing voltage corresponds to a first initial optical compensation parameter written into the control terminal of the driving circuit under a condition that the light emitting element displays a first brightness, the second pre-stored sensing voltage corresponds to a second initial optical compensation parameter written into the control terminal of the driving circuit under a condition that the light emitting element displays a second brightness, and the first brightness is different from the second brightness.

For example, at least one embodiment of the present disclosure provides a compensation method of a pixel circuit, further including: updating a compensation data voltage lookup table, wherein the compensation data voltage lookup table comprises a first optical compensation parameter and a second optical compensation parameter, an initial value of the first optical compensation parameter is the first initial optical compensation parameter, an initial value of the second optical compensation parameter is the second initial optical compensation parameter, and updating the compensation data voltage lookup table comprises: updating the value of the first optical compensation parameter using the first compensation data voltage; and updating the value of the second optical compensation parameter using the second compensation data voltage.

For example, at least one embodiment of the present disclosure provides a compensation method of a pixel circuit, further including: calculating a plurality of display compensation data voltages in a case where the light emitting element displays a plurality of luminances, according to the first optical compensation parameter and the second optical compensation parameter.

For example, in a compensation method of a pixel circuit provided in at least one embodiment of the present disclosure, the plurality of display compensation data voltages are obtained by the following calculation formula:

or

Wherein, V_mFor the mth display compensation data voltage among the plurality of display compensation data voltages, V1 is the first optical compensation parameter, V2 is the second optical compensation parameter, L1 is the first luminance, L2 is the second luminance, Lm is a luminance parameter corresponding to the mth display compensation data voltage, and M is a positive integer.

For example, in a compensation method of a pixel circuit provided in at least one embodiment of the present disclosure, acquiring a voltage of a control terminal of the driving circuit as a first compensation data voltage includes: adjusting a value of a first detection data voltage written in a control terminal of the driving circuit, so that after the sensing signal line is charged by the driving circuit for a first time, the first sensing voltage on the sensing signal line approaches the first pre-stored sensing voltage, and under the condition that the first sensing voltage on the sensing signal line is equal to the first pre-stored sensing voltage, acquiring the adjusted first detection data voltage as the first compensation data voltage; acquiring the voltage of the control terminal of the driving circuit as a second compensation data voltage comprises: and adjusting a value of a second detection data voltage written in a control terminal of the driving circuit, so that after the sensing signal line is charged by the driving circuit for a second time, the second sensing voltage on the sensing signal line approaches the second pre-stored sensing voltage, and under the condition that the second sensing voltage on the sensing signal line is equal to the second pre-stored sensing voltage, acquiring the adjusted second detection data voltage as the second compensation data voltage.

For example, in a compensation method of a pixel circuit provided in at least one embodiment of the present disclosure, the first time is the same as the second time in duration.

For example, in a compensation method of a pixel circuit provided in at least one embodiment of the present disclosure, a first compensation data voltage obtained in an nth frame is used as a first detection data voltage in an N +1 th frame, a second compensation data voltage obtained in the nth frame is used as a second detection data voltage in the N +1 th frame, N is an integer greater than 0; the first initial optical compensation parameter serves as a first detected data voltage in a first frame, and the second initial optical compensation parameter serves as a second detected data voltage in the first frame.

For example, in a compensation method of a pixel circuit provided in at least one embodiment of the present disclosure, the first pre-stored sensing voltage and the second pre-stored sensing voltage are obtained by: writing the first initial optical compensation parameter into a control end of the driving circuit to enable the driving circuit to be conducted, and after the sensing signal line is charged for the first time through the driving circuit, acquiring the voltage on the sensing signal line as the first pre-stored sensing voltage; and writing the second initial optical compensation parameter into the control end of the driving circuit to enable the driving circuit to be conducted, and after the sensing signal line is charged by the driving circuit for the second time, acquiring the voltage on the sensing signal line as the second pre-stored sensing voltage.

For example, in a compensation method of a pixel circuit provided in at least one embodiment of the present disclosure, the first initial optical compensation parameter and the second initial optical compensation parameter are obtained by: acquiring a voltage written into a control end of the driving circuit as the first initial optical compensation parameter under the condition that the light-emitting element displays the first brightness; and acquiring the voltage written into the control end of the driving circuit as the second initial optical compensation parameter under the condition that the light-emitting element displays the second brightness.

For example, in a compensation method of a pixel circuit provided in at least one embodiment of the present disclosure, the first luminance is 1/4 of the maximum luminance of the light emitting element, and the second luminance is 1/4 of the maximum luminance of the light emitting element.

At least one embodiment of the present disclosure provides a driving method of a pixel circuit, including: determining a display luminance of a light emitting element electrically connected to the pixel circuit; the compensation method according to any one embodiment of the present disclosure obtains a first compensation data voltage and a second compensation data voltage, and calculates a display compensation data voltage corresponding to the display brightness according to the first compensation data voltage and the second compensation data voltage; and applying the display compensation data voltage to the pixel circuit to drive the light emitting element to emit light.

At least one embodiment of the present disclosure provides a compensation apparatus, including: the device comprises a control circuit, a sensing voltage detection circuit and a compensation voltage acquisition circuit; the compensation device is configured to compensate a pixel circuit, the pixel circuit comprises a driving circuit, the driving circuit comprises a control end and a first end, the first end of the driving circuit is configured to be electrically connected with a sensing signal line and a light-emitting element, and the control circuit is configured to control the driving circuit to be conducted to charge the sensing signal line; the sensing voltage detection circuit is configured to detect a first sensing voltage and a second sensing voltage on the sensing signal line, respectively; the compensation voltage acquisition circuit is configured to acquire a voltage of a control terminal of the driving circuit as a first compensation data voltage under the condition that the first sensing voltage is equal to a first pre-stored sensing voltage; and acquiring a voltage of the control terminal of the driving circuit as a second compensation data voltage under the condition that the second sensing voltage is equal to a second pre-stored sensing voltage, wherein the first compensation data voltage and the second compensation data voltage are used for display compensation operation of the pixel circuit, the first pre-stored sensing voltage corresponds to a first initial optical compensation parameter written into the control terminal of the driving circuit under the condition that the light emitting element displays a first brightness, the second pre-stored sensing voltage corresponds to a second initial optical compensation parameter written into the control terminal of the driving circuit under the condition that the light emitting element displays a second brightness, and the first brightness is different from the second brightness.

For example, the compensation apparatus provided by at least one embodiment of the present disclosure further includes a compensation parameter update circuit, wherein the compensation parameter update circuit is configured to update a value of a first optical compensation parameter in a compensation data voltage lookup table using the first compensation data voltage, and update a value of a second optical compensation parameter in the compensation data voltage lookup table using the second compensation data voltage, wherein an initial value of the first optical compensation parameter is the first initial optical compensation parameter, and an initial value of the second optical compensation parameter is the second initial optical compensation parameter.

At least one embodiment of the present disclosure provides a display device including the compensation device, the pixel circuit, and the sensing signal line according to any one of the embodiments of the present disclosure, wherein the compensation device is electrically connected to the pixel circuit and the sensing signal line, respectively.

For example, in a display device provided in at least one embodiment of the present disclosure, the pixel circuit further includes a data writing circuit electrically connected to the control terminal of the driving circuit and configured to be turned on during data writing to write a data voltage to the control terminal of the driving circuit.

For example, in a display device provided in at least one embodiment of the present disclosure, the pixel circuit further includes a sensing circuit, a first terminal of the sensing circuit is electrically connected to the sensing signal line, a second terminal of the sensing circuit is electrically connected to the first terminal of the driving circuit and the light emitting element, and the sensing circuit is configured to be turned on during data writing to write a reference voltage to the first terminal of the driving circuit and to be turned on during detection to charge the sensing signal line.

For example, in a display device provided in at least one embodiment of the present disclosure, the pixel circuit further includes a storage circuit, the driving circuit further includes a second terminal configured to receive a power supply voltage, and the first terminal and the second terminal of the storage circuit are electrically connected to the control terminal and the first terminal of the driving circuit, respectively.

Drawings

To more clearly illustrate the technical solutions of the embodiments of the present disclosure, the drawings of the embodiments will be briefly introduced below, and it is apparent that the drawings in the following description relate only to some embodiments of the present disclosure and are not limiting to the present disclosure.

Fig. 1 is a flowchart of a compensation method of a pixel circuit according to some embodiments of the present disclosure;

fig. 2 is a schematic diagram of a pixel circuit according to some embodiments of the present disclosure;

FIGS. 3A and 3B are timing diagrams of signals of the pixel circuit shown in FIG. 2;

fig. 4 is a flowchart of a driving method of a pixel circuit according to some embodiments of the present disclosure;

fig. 5 is a schematic block diagram of a compensation apparatus provided in some embodiments of the present disclosure; and

fig. 6 is a schematic view of a display device according to some embodiments of the present disclosure.

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present disclosure more clear, the technical solutions of the embodiments of the present disclosure will be described below clearly and completely with reference to the accompanying drawings of the embodiments of the present disclosure. It is to be understood that the described embodiments are only a few embodiments of the present disclosure, and not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the described embodiments of the disclosure without any inventive step, are within the scope of protection of the disclosure.

Unless otherwise defined, technical or scientific terms used herein shall have the ordinary meaning as understood by one of ordinary skill in the art to which this disclosure belongs. The use of "first," "second," and similar terms in this disclosure is not intended to indicate any order, quantity, or importance, but rather is used to distinguish one element from another. The word "comprising" or "comprises", and the like, means that the element or item listed before the word covers the element or item listed after the word and its equivalents, but does not exclude other elements or items. The terms "connected" or "coupled" and the like are not restricted to physical or mechanical connections, but may include electrical connections, whether direct or indirect. "upper", "lower", "left", "right", and the like are used merely to indicate relative positional relationships, and when the absolute position of the object being described is changed, the relative positional relationships may also be changed accordingly.

To maintain the following description of the embodiments of the present disclosure clear and concise, a detailed description of some known functions and components have been omitted from the present disclosure.

Due to the influence of factors such as a manufacturing process and temperature variation, threshold voltages of driving transistors of pixel circuits in an Organic Light Emitting Diode (OLED) display device may be different and may drift, so that the brightness of a display screen of the OLED display device is not uniform, and a good display effect is difficult to achieve.

In order to solve the above problem, the threshold voltage of the driving transistor of each pixel circuit in the OLED display device is usually compensated by an optical compensation method before the OLED display device is shipped, and the threshold voltage of the driving transistor of each pixel circuit in the OLED display device is compensated by an electrical compensation method after the OLED display device is shipped.

However, since the optical compensation method and the electrical compensation method are performed at two stages before and after the OLED display device is shipped from a factory, it is difficult to combine the optical compensation and the electrical compensation in the process of compensating for the threshold voltage of the driving transistor of each pixel circuit in the OLED display device, and the luminance compensation effect of the OLED display device is limited. For example, after the OLED display device is shipped, only the difference in the threshold voltage of each driving transistor can be electrically compensated, and the OLED display device cannot achieve the luminance display effect after optical compensation before shipment.

At least one embodiment of the present disclosure provides a compensation method and a driving method for a pixel circuit, in which optical compensation and electrical compensation are combined to achieve a common compensation effect of the electrical compensation and the optical compensation in a display device, thereby greatly improving the quality of a display image. Meanwhile, the compensation method can also realize real-time compensation on the display device in the display process.

At least one embodiment of the present disclosure further provides a compensation device and a display device including the compensation device, so that after the compensation device performs brightness compensation on each pixel circuit of the display device, the display device achieves a better image display effect.

Hereinafter, some embodiments of the present disclosure will be described in detail with reference to the accompanying drawings. It should be noted that the same reference numerals in different figures will be used to refer to the same elements that have been described.

Fig. 1 illustrates a compensation method of a pixel circuit according to some embodiments of the present disclosure. As shown in fig. 1, the compensation method includes:

step S10: controlling the drive transistor to be conducted to charge the sensing signal line, and acquiring the voltage of the grid electrode of the drive transistor as a first compensation data voltage under the condition that the first sensing voltage on the sensing signal line is equal to a first pre-stored sensing voltage;

step S20: and controlling the driving transistor to be conducted to charge the sensing signal line, and acquiring the voltage of the grid electrode of the driving transistor as a second compensation data voltage under the condition that the second sensing voltage on the sensing signal line is equal to a second pre-stored sensing voltage.

The compensation method will be described below in conjunction with a specific pixel circuit. For example, a display device may include a plurality of sub-pixels (i.e., pixel units) arranged in an array, each sub-pixel including a pixel circuit as described below.

Fig. 2 is a schematic diagram of a pixel circuit 10 according to some embodiments of the present disclosure. As shown in fig. 2, the pixel circuit 10 includes a drive circuit 100, a data write circuit 200, a sense circuit 300, and a memory circuit 400.

For example, the driving circuit 100 includes a driving transistor T1, and the control terminal of the driving circuit 100 includes a gate of the driving transistor T1 and is configured to receive the data voltage; the first terminal of the driving circuit 100 includes a first pole (e.g., source) of the driving transistor T1, and is electrically connected to the sensing signal line SEN and the light emitting element EL; the second terminal of the driving circuit 100 includes a second pole (e.g., a drain) of the driving transistor T1, and is connected to the first power voltage terminal to receive the first power voltage Vdd.

For example, the data writing circuit 200 includes a data writing transistor T2, and the control terminal of the data writing circuit 200 includes a gate of the data writing transistor T2 and is configured to be connected to the scan line to receive the scan signal G1; the first terminal of the data write circuit 200 includes a first pole of the data write transistor T2 and is configured to be electrically connected to the gate of the driving transistor T1 (i.e., the control terminal of the driving circuit 100); the second terminal of the data write circuit 200 includes a second pole of the data write transistor T2, and is configured to be connected with the data line DAT. For example, in a data writing process, the data writing transistor T2 is turned on in response to the scan signal G1 to write a data voltage supplied from the data line DAT to the gate of the driving transistor T1, and the data voltage is stored by a storage circuit as described below.

For example, the storage circuit 400 includes a storage capacitor C1. The first terminal of the memory circuit 400 includes a first pole of the storage capacitor C1 and is configured to be electrically connected to the gate of the driving transistor T1 and the first pole of the data writing transistor T2, and the second terminal of the memory circuit 400 includes a second pole of the storage capacitor C1 and is configured to be electrically connected to the first pole of the driving transistor T1 and the light emitting element EL. The storage capacitor C1 is configured to store the data voltage written through the data writing transistor T2. For example, in a case where the data write transistor T2 is turned off, the driving transistor T1 is turned on by the data voltage stored in the storage capacitor C1 and outputs a current to charge the sensing signal line SEN; further, due to the capacitive coupling effect of the storage capacitor C1, when the voltage of the first electrode of the driving transistor T1 rises, the voltage of the gate electrode of the driving transistor T1 also rises, so that the voltage difference between the gate electrode and the first electrode of the driving transistor T1 is kept constant, and the magnitude of the current output by the driving transistor T1 is kept constant.

For example, the sensing circuit 300 includes a sensing transistor T3, the control terminal of the sensing circuit 300 includes the gate of the sensing transistor T3, and is configured to be electrically connected with the sensing signal control line to receive the sensing control signal G2; a first terminal of the sensing circuit 300 includes a first pole of the sensing transistor T3 and is configured to be electrically connected to the sensing signal line SEN; the second terminal of the sensing circuit 300 includes a second pole of the sensing transistor T3, and is configured to be electrically connected to the first pole of the driving transistor T1 and the light emitting element EL. For example, during data writing, the sensing transistor T3 is turned on in response to the sensing control signal G2, and the reference voltage is written to the first pole of the driving transistor T1 via the sensing transistor T3; for example, during the sensing process, the sensing transistor T3 is turned on in response to the sensing control signal G2, and the current flowing through the driving transistor T1 is transmitted to the sensing signal line SEN via the sensing transistor T3 to charge the sensing signal line SEN (i.e., the capacitance or parasitic capacitance connected thereto).

For example, as shown in fig. 2, the first electrode of the sensing transistor T3 may also be electrically connected to the reference voltage terminal through the first switching element SW1 to receive the reference voltage Vref, and electrically connected to the detection circuit 500 through the second switching element SW 2. For example, in the case where the sensing transistor T3 is turned on, when the first switching element SW1 is turned on and the second switching element SW2 is turned off, the reference voltage provided from the reference voltage terminal is written into the first pole of the driving transistor T1 via the sensing signal line SEN and the sensing transistor T3. For example, in the case where the sensing transistor T3 is turned on, when the first switching element SW1 is turned off and the second switching element SW2 is turned on, the current output from the driving transistor T1 may be transmitted to the sensing signal line SEN via the sensing transistor T3 to charge the sensing signal line SEN. For example, with the sense transistor T3 turned off, when the first switching element SW1 is turned off and the second switching element SW2 is turned on, the voltage on the sense signal line SEN may be acquired by the detection circuit 500.

For example, the detection circuit 500 may be implemented in various suitable forms, e.g., may include an amplification sub-circuit that amplifies the voltage detected from the sense signal line SEN to obtain an amplified voltage signal, an analog-to-digital conversion (ACD) circuit, etc., which is converted by the analog-to-digital conversion circuit to a digital signal that may be used for subsequent analysis, calculation, etc.

It should be noted that the first switch element SW1 and the second switch element SW2 may be in an off state and an on state, for example, the first switch element SW1 and the second switch element SW2 may be transistors or other types of switch elements.

It should be noted that, in the pixel circuit 10 shown in fig. 2, the light emitting element EL may be, for example, various types of Organic Light Emitting Diodes (OLEDs), such as top emission, bottom emission, double-side emission, and the like, and the embodiment of the disclosure does not limit this. As shown in fig. 2, the anode of the exemplary OLED is electrically connected to a first pole of the driving transistor T1, and the cathode receives a second power supply voltage Vss, which is lower than the first power supply voltage Vdd. The light emitting element EL may be, for example, a quantum dot light emitting diode (QLED) or the like, which is not limited in the embodiment of the present disclosure. For example, the light emitting element EL may emit red light, green light, blue light, white light, or the like.

For example, before the display apparatus including the pixel circuit 10 is shipped, the first luminance L1 and the second luminance L2 of the light emitting element EL may be determined first, and the light emitting element EL is compensated to be uniform at the first luminance L1 and the second luminance L2 by adjusting the data voltage written to the gate of the driving transistor T1 using the optical compensation device, that is, the display apparatus achieves uniform display at both the first luminance and the second luminance. The first luminance L1 and the second luminance L2 are different, for example, the first luminance L1 may be the maximum luminance of the light emitting element EL, and the second luminance L2 may be 1/4 of the maximum luminance of the light emitting element EL; for example, the first luminance L1 may be the maximum luminance of the light emitting element EL, and the second luminance L2 may be 1/9 of the maximum luminance of the light emitting element EL, which is not limited by the embodiment of the present disclosure.

For example, the luminance of the light emitting element EL can be acquired by detecting the luminance of the light emitting element EL with, for example, a luminance detecting device.

For example, the first initial optical compensation parameter and the second initial optical compensation parameter may be obtained before the display device including the pixel circuit 10 is shipped from the factory. For example, acquiring the first initial optical compensation parameter and the second initial optical compensation parameter includes: acquiring the voltage written into the control end of the drive circuit as a first initial optical compensation parameter under the condition that the light-emitting element displays first brightness; and acquiring the voltage written into the control end of the drive circuit as a second initial optical compensation parameter under the condition that the light-emitting element displays the second brightness.

For example, as shown in conjunction with fig. 2, in some embodiments, after determining the first luminance L1 and the second luminance L2, the first initial optical compensation parameter VP1 may be obtained by: acquiring the luminance of the light emitting element EL, and acquiring the data voltage written to the gate of the driving transistor T1 as a first initial optical compensation parameter VP1 in the case where the light emitting element EL displays the first luminance L1; the second initial optical compensation parameter VP2 may be obtained by: the luminance of the light emitting element EL is acquired, and in the case where the light emitting element EL displays the second luminance L2, the data voltage written to the gate of the driving transistor T1 is acquired as the second initial optical compensation parameter VP 2. Thereafter, the obtained first initial optical compensation parameter VP1 and second initial optical compensation parameter VP2 are stored in a memory (e.g., a flash memory).

For example, the first initial optical compensation parameter VP1 and the second initial optical compensation parameter VP2 are both optically compensated data voltages, and the first initial optical compensation parameter VP1 corresponds to the first luminance L1, and the second initial optical compensation parameter VP2 corresponds to the second luminance L2.

For example, the first and second pre-stored sensing voltages may be obtained before a display device including the pixel circuit 10 is shipped from a factory. The first pre-stored sensing voltage may be determined based on the first initial optical compensation parameter VP1, and the second pre-stored sensing voltage may be determined based on the second initial optical compensation parameter VP 2. For example, in steps S10 and S20, the first and second pre-stored sense voltages are obtained by: writing a first initial optical compensation parameter into a control end of a driving circuit to enable the driving circuit to be conducted, and after the driving circuit charges a sensing signal line for a first time, acquiring voltage on the sensing signal line as first pre-stored sensing voltage; and writing a second initial optical compensation parameter into the control end of the driving circuit to enable the driving circuit to be conducted, and after the driving circuit charges the sensing signal line for a second time, acquiring the voltage on the sensing signal line as a second pre-stored sensing voltage.

For example, as shown in fig. 2, before a display device including the pixel circuit 10 is shipped, the first initial optical compensation parameter VP1 is written to the gate of the driving transistor T1 to turn on the driving transistor T1, and after the sensing signal line SEN is charged for a first time S1 by the driving transistor T1, the first pre-stored sensing voltage VT1 is obtained by detecting a corresponding voltage value on the sensing signal line SEN; the second initial optical compensation parameter VP2 is written to the gate of the driving transistor T1 to turn on the driving transistor T1, and after the sensing signal line SEN is charged for a second time S2 through the driving transistor T1, the second pre-stored sensing voltage VT2 is obtained by detecting a corresponding voltage value on the sensing signal line SEN.

Taking as an example that the driving transistor T1, the data writing transistor T2 and the sensing transistor T3 in the pixel circuit 10 shown in fig. 2 are all N-type transistors, and the first switching element SW1 and the second switching element SW2 are both turned on under the control of a low level signal and turned off under the control of a high level signal, the following describes the process of obtaining the first pre-stored sensing voltage VT1 and the second pre-stored sensing voltage VT2 in conjunction with the signal timing diagrams of the pixel circuit 10 shown in fig. 3A and 3B.

As shown in fig. 2 and 3A, at the stage T1, the data writing transistor T2 is turned on in response to the scan signal G1 of high level, the sensing transistor T3 is turned on in response to the sensing control signal G2 of high level, the first switching element SW1 is turned on, and the second switching element SW2 is turned off. The first initial optical compensation parameter VP1 is written to the gate of the driving transistor T1 through the data writing transistor T2, and a reference voltage Vref (e.g., a low level voltage or a ground voltage) provided by a reference voltage terminal is written to the first pole (i.e., source) of the driving transistor T1 via the sensing transistor T3, thereby turning on the driving transistor T1.

For example, in order to turn on the driving transistor T1, the difference between the first initial optical compensation parameter VP1 and the reference voltage Vref cannot be lower than the threshold voltage Vth of the driving transistor T1, i.e., VP1-Vref ≧ Vth.

At the stage T2, the data writing transistor T2 is turned off in response to the low level scan signal G1, the sensing transistor T3 is turned on in response to the high level sensing control signal G2, the first switching element SW1 is turned off, and the second switching element SW2 is turned on. The driving transistor T1 Is turned on under the control of the voltage (i.e., the first initial optical compensation parameter VP1) stored in the storage capacitor C1, and the output current Is1 charges the sensing signal line SEN for a first time S1. Due to the capacitive coupling effect of the storage capacitor C1, during the first time S1 when the sensing signal line SEN Is charged, the current Is1 output by the driving transistor T1 remains unchanged, so that the voltage value on the sensing signal line SEN increases linearly with time.

At the stage T3, the data writing transistor T2 is turned off in response to the low level scan signal G1, the sensing transistor T3 is turned off in response to the low level sense control signal G2, the first switching element SW1 is turned off, and the second switching element SW2 is turned on. After the sensing signal line SEN is charged for the first time S1, the voltage on the sensing signal line SEN, which is the first pre-stored sensing voltage VT1, may be obtained by the detection circuit 500.

As shown in fig. 2 and 3B, at the stage T4, the data writing transistor T2 is turned on in response to the scan signal G1 of high level, the sensing transistor T3 is turned on in response to the sensing control signal G2 of high level, the first switching element SW1 is turned on, and the second switching element SW2 is turned off. The second initial optical compensation parameter VP2 is written to the gate of the driving transistor T1 through the data writing transistor T2, and a reference voltage Vref (e.g., a low level voltage or a ground voltage) provided by a reference voltage terminal is written to the first pole (i.e., source) of the driving transistor T1 via the sensing transistor T3, thereby turning on the driving transistor T1.

For example, in order to turn on the driving transistor T1, the difference between the second initial optical compensation parameter VP2 and the reference voltage Vref cannot be lower than the threshold voltage Vth of the driving transistor T1, i.e., VP2-Vref ≧ Vth.

At the stage T5, the data writing transistor T2 is turned off in response to the low level scan signal G1, the sensing transistor T3 is turned on in response to the high level sensing control signal G2, the first switching element SW1 is turned off, and the second switching element SW2 is turned on. The driving transistor T1 Is turned on under the control of the voltage (i.e., the second initial optical compensation parameter VP2) stored in the storage capacitor C1, and the output current Is2 charges the sensing signal line SEN for a second time S2. Due to the capacitive coupling effect of the storage capacitor C1, during the second time S2 when the sensing signal line SEN Is charged, the current Is2 output by the driving transistor T1 remains unchanged, so that the voltage value on the sensing signal line SEN increases linearly with time.

For example, the second time S2 may be the same as the first time S1, or may be different from the first time S1, which is not limited by the embodiment of the disclosure. The second time S2 is the same as the first time S1.

At the stage T6, the data writing transistor T2 is turned off in response to the low level scan signal G1, the sensing transistor T3 is turned off in response to the low level sense control signal G2, the first switching element SW1 is turned off, and the second switching element SW2 is turned on. After the sensing signal line SEN is charged for the second time S2, the voltage on the sensing signal line SEN, which is the second pre-stored sensing voltage VT2, may be obtained by the detection circuit 500.

The acquired first and second pre-stored sensing voltages VT1 and VT2, and the corresponding first and second times S1 and S2 are stored in a memory (e.g., a flash memory) for electrically compensating the threshold voltage Vth of the driving transistor T1 and the process parameter K in the pixel circuit 10 after the display device including the pixel circuit 10 is shipped from the factory.

Meanwhile, before the display device leaves the factory, the initial threshold voltage of the driving transistor T1 may be derived according to the obtained first pre-stored sensing voltage VT1, second pre-stored sensing voltage VT2, first initial optical compensation parameter VP1 and second initial optical compensation parameter VP 2. Further, a plurality of initial optical compensation voltages in the case where the light emitting element EL displays a plurality of luminances may be calculated from the first initial optical compensation parameter VP1 and the second initial optical compensation parameter VP 2. The plurality of initial optical compensation voltages includes a first initial optical compensation parameter VP1 and a second initial optical compensation parameter VP 2.

For example, the gray scale levels of the display device may include 256 gray scale levels (gray scales of 0 to 255), that is, each pixel is represented by 8-bit data, and the plurality of luminances displayed by the light emitting elements EL may correspond to all the gray scale levels one to one.

For example, at the stage T2, since the driving transistor T1 Is turned on and in the saturation state, the current Is1 can be obtained according to the current formula that the driving transistor T1 Is in the saturation state, that Is:

Is1＝K(VP1-Vref-Vth)² (1)

where K is a process constant of the driving transistor T1.

For example, at the stage T5, since the driving transistor T1 Is turned on and in the saturation state, the current Is2 can be obtained according to the current formula that the driving transistor T1 Is in the saturation state, that Is:

Is2＝K(VP2-Vref-Vth)² (2)

where K is a process constant of the driving transistor T1.

Since the luminance value L of the light-emitting element EL Is proportional to the current Is flowing through the light-emitting element EL during the lighting of the light-emitting element EL, the relationship between the luminance value L of the light-emitting element EL and the current Is can be expressed as:

Is＝a·L (3)

wherein a is a constant.

For example, the luminance value L may be a normalized luminance value, that is, 0 ≦ L ≦ 1, and when L is1, the light emitting element EL displays luminance corresponding to 255 gradations, and when L is 0, the light emitting element EL displays luminance corresponding to 0 gradations. Therefore, the current Is1 output from the driving transistor T1 at the stage T2 and the current Is2 output from the driving transistor T1 at the stage T5 can be expressed as:

Is1＝Imax·L1 (4)

Is2＝Imax·L2 (5)

where Imax is an output current of the driving transistor T1 corresponding to the light emitting element EL displaying 255 gradations, that is, an output current corresponding to the maximum luminance of the light emitting element EL; l1 is the first brightness, L2 is the second brightness, and the first brightness and the second brightness are normalized brightness, so that L1 is greater than or equal to 0 and less than or equal to 1, and L2 is greater than or equal to 0 and less than or equal to 1. For example, in some embodiments, if the first luminance is the maximum luminance of the light emitting element EL and the second luminance is 1/4 of the maximum luminance of the light emitting element EL, L1 is1 and L2 is 1/4.

Therefore, according to the above-described relational expressions (1) to (5), it can be derived that the threshold voltage Vth of the driving transistor T1 has a value:

meanwhile, according to the current-voltage formula, it can be known that:

wherein Vdata is a data voltage supplied through the data line DAT.

From the above-mentioned relations (1) to (7), it is also possible to derive the data voltage corresponding to an arbitrary normalized luminance value L of the light emitting element EL, that is:

further, since the first pre-stored sensing voltage VT1, which is acquired after the first time S1 is charged to the sensing signal line SEN, and the second pre-stored sensing voltage VT2, which is acquired after the second time S2 is charged to the sensing signal line SEN, satisfy the following relational expression:

Is1·S1＝VT1·C (10)

Is2·S2＝VT2·C (11)

where C is the capacitance value of the capacitance to which the sense signal line SEN is connected.

Further, it can be derived from the above relations (1) to (11) that the value of the process parameter K of the driving transistor T1 is:

the specific value of Vth can be obtained by the above-described relational expression (6).

Therefore, before shipment of the display device including the pixel circuit 10, a plurality of initial optical compensation voltages corresponding to the respective luminance values L of the light emitting elements EL may be calculated based on the first initial optical compensation parameter VP1 and the second initial optical compensation parameter VP2, so that the data voltage Vdata written to the gate of the driving transistor T1 at the respective luminance values L of the corresponding light emitting elements EL may be compensated.

After the display device including the pixel circuit 10 is shipped from the factory, as shown in fig. 1, the threshold voltage Vth of the driving transistor T1 in the pixel circuit 10, the process parameter K, and the like may be electrically compensated based on the stored first and second pre-stored sensing voltages VT1 and VT 2.

For example, in step S10 shown in fig. 1, acquiring the voltage of the gate of the driving transistor T1 as the first compensated data voltage VC1 includes: the value of the first sensing data voltage VE1 written in the driving transistor T1 is adjusted such that the first sensing voltage Vsen1 on the sensing signal line SEN approaches the first pre-stored sensing voltage VT1 after the sensing signal line SEN is charged for the first time S1 by the driving transistor T1, and the adjusted first sensing data voltage VE1 is obtained as the first compensated data voltage VC1 under the condition that the first sensing voltage Vsen1 on the sensing signal line SEN is equal to the first pre-stored sensing voltage VT 1.

For example, in a display process, one frame time includes a display phase and a blanking phase disposed between adjacent display phases. Each display stage is used for displaying a frame of image, and the time length of each display stage is equal to the time from the display of the first pixel point of the frame of image to the display of the last pixel point of the frame of image.

For example, the first initial optical compensation parameter VP1 may be used as the first detected data voltage for the first frame during display; for example, the first compensation data voltage obtained at the nth frame may be used as the first detection data voltage in the (N + 1) th frame (N is an integer greater than 0).

For example, in step S20 shown in fig. 1, acquiring the voltage of the gate of the driving transistor T1 as the second compensated data voltage VC2 includes: the value of the second sensing data voltage VE2 written in the driving transistor T1 is adjusted such that the second sensing voltage Vsen2 on the sensing signal line SEN approaches the second pre-stored sensing voltage VT2 after the sensing signal line SEN is charged for the second time S2 by the driving transistor T1, and the adjusted second sensing data voltage VE2 is obtained as the second compensated data voltage VC2 in a case where the second sensing voltage Vsen2 on the sensing signal line SEN is equal to the second pre-stored sensing voltage VT 2.

For example, the second initial optical compensation parameter VP2 may be used as the second detected data voltage for the first frame during display; for example, the second compensation data voltage obtained at the nth frame may be used as the second detection data voltage in the (N + 1) th frame (N is an integer greater than 0).

For example, taking the process of acquiring the first compensated data voltage VC1 in step S10 as an example, after writing the first sensing data voltage VE1 to the gate of the driving transistor T1 and charging the sensing signal line SEN through the driving transistor T1 for the first time S1, if the value of the acquired first sensing voltage Vsen1 on the sensing signal line SEN is less than the first pre-stored sensing voltage VT1, the value of the first sensing data voltage VE1 is increased; if the value of the first sensing voltage Vsen1 on the sensing signal line SEN is greater than the first pre-stored sensing voltage VT1, the value of the first sensing data voltage VE1 is turned down to make the value of the first sensing voltage Vsen1 approach the first pre-stored sensing voltage VT1 continuously until the first sensing voltage Vsen1 on the sensing signal line SEN is equal to the first pre-stored sensing voltage VT1 after the sensing signal line SEN is charged for the first time S1 by writing the first sensing data voltage VE 1.

For example, in some embodiments of the present disclosure, in acquiring the first and second compensated data voltages VC1 and VC2 every frame, the initial value of the first detected data voltage VE1 and the initial value of the second detected data voltage VE2 written to the gate of the driving transistor T1 may also be fixed values. For example, in each frame, the initial values of the written first sensing data voltages VE1 are all the first initial optical compensation parameters VP1, and the initial values of the written second sensing data voltages VE2 are all the second initial optical compensation parameters VP 2.

For example, when the pixel circuit 10 Is compensated by the compensation method, in step S10, since the first sensing voltage Vsen1 on the sensing signal line SEN Is equal to the first pre-stored sensing voltage VT1, it can be ensured that when the first compensation data voltage VC1 Is written to the driving transistor T1, the current flowing through the light emitting element EL Is the same as the current Is1 optically compensated before factory shipment, so that the light emitting element EL can be made to reach the same first luminance L1 as after optical compensation by the first compensation data voltage VC 1. The compensation principle of step S20 is the same as that of step S10, and is not described herein again.

For example, when the light emitting element EL is driven to emit light by the pixel circuit 10 to perform a display operation, the compensation method shown in fig. 1 may be performed in a blanking period of one frame time, so that real-time compensation of the pixel circuit 10 can be realized.

For example, after the first compensation data voltage VC1 and the second compensation data voltage VC2 are obtained through steps S10 and S20, the data voltage applied to the driving transistor T1 in the case where the threshold voltage Vth of the driving transistor T1 and the plurality of luminance values L of the corresponding light emitting element EL are obtained is calculated based on the first compensation data voltage VC1 and the second compensation data voltage VC2, so that the optical compensation and the electrical compensation are combined, and the light emitting element EL can still achieve the luminance display effect of the optical compensation after being shipped from the factory.

For example, as shown in fig. 1, the compensation method of the pixel circuit 10 may further include:

step S30: the compensation data voltage lookup table is updated.

For example, in order to compensate for the threshold voltage Vth of the driving transistor T1 and apply the compensated display data voltage to the pixel circuit 10 when the light emitting element EL is driven to emit light every frame, a compensation data voltage lookup table of the pixel circuit 10 may be established. For example, the compensation data voltage lookup table includes a first optical compensation parameter V1 and a second optical compensation parameter V2. For example, the initial value of the first optical compensation parameter V1 may be set to the first initial optical compensation parameter VP1, and the initial value of the second optical compensation parameter V2 may be set to the second initial optical compensation parameter VP 2.

The compensation data voltage lookup table is, for example, a relational data table or the like, and can be stored in a memory (e.g., a flash memory) of the display device, so that the display device can be called conveniently in the display process; and, the state of the compensation data voltage lookup table can be set to be changeable, so that the display device can modify the data items therein as required during the operation.

For example, after the first and second compensation data voltages VC1 and VC2 are obtained through steps S10 and S20 in the blanking period, step S30 may include updating the value of the first optical compensation parameter V1 using the first compensation data voltage VC1, and updating the value of the second optical compensation parameter V2 using the second compensation data voltage VC 2. Further, the first optical compensation parameter V1 is the display compensation data voltage corresponding to the first luminance L1 of the light emitting element EL, the second optical compensation parameter V2 is the display compensation data voltage corresponding to the second luminance L2 of the light emitting element EL, and the first optical compensation parameter V1 and the second optical compensation parameter V2 can be updated in real time.

step S40: a plurality of display compensation data voltages in a case where the light emitting element displays a plurality of luminances are calculated based on the first optical compensation parameter and the second optical compensation parameter.

For example, the first optical compensation parameter may be basedThe number V1 and the second optical compensation parameter V2 calculate a plurality of display compensation data voltages in the case where the light emitting element EL displays a plurality of luminance values L. The calculation method of the display compensation data voltages is the same as the above equations (1) - (9), and is not repeated herein, for example, the mth display compensation data voltage V_mComprises the following steps:

or

Wherein Vm is an mth display compensation data voltage among the plurality of display compensation data voltages, V1 is a first optical compensation parameter, V2 is a second optical compensation parameter, L1 is a first luminance, L2 is a second luminance, Lm is a luminance parameter corresponding to the mth display compensation data voltage, and M is a positive integer.

For example, when the reference voltage Vref is the ground voltage, i.e., when Vref is equal to 0, the mth display compensation data voltage V_mComprises the following steps:

or

Therefore, the compensation method can be carried out in the real-time display process, the effects of optical compensation and electrical compensation are achieved, and meanwhile, the data bandwidth of a corresponding memory is not required to be increased, namely, the effects of optical compensation and electrical compensation are achieved only by using the data bandwidth required by the electrical compensation, and the brightness uniformity of a display picture is greatly improved.

For example, in the display process, the compensation method may be performed in a blanking period of each frame, so that the pixel circuit 10 may be compensated in each frame, and the brightness uniformity of the display image is improved. For example, the compensation method may be performed in a blanking period of two or more frames at intervals, so as to reduce the operation amount of the display device including the pixel circuit 10 and thus reduce the power consumption of the display device in the case of satisfying the uniformity of the display luminance.

Some embodiments of the present disclosure further provide a driving method of the pixel circuit 10, and fig. 4 is a flowchart of the driving method of the pixel circuit 10 according to some embodiments of the present disclosure. As shown in fig. 4, the driving method includes:

step S100: determining a display luminance of a light emitting element electrically connected to the pixel circuit;

step S200: obtaining a first compensation data voltage and a second compensation data voltage, and calculating a display compensation data voltage corresponding to display brightness according to the first compensation data voltage and the second compensation data voltage;

step 300: the display compensation data voltage is applied to the pixel circuit to drive the light emitting element to emit light.

For example, in step S100, the display luminance Lm that needs to be displayed by the light emitting element in the pixel circuit of each sub-pixel may be determined according to the content of one frame of the display screen.

For example, in step S200, the first compensated data voltage VC1 and the second compensated data voltage VC2 may be obtained according to a compensation method of the pixel circuit according to any embodiment of the disclosure, for example, the first compensated data voltage VC1 and the second compensated data voltage VC2 may be obtained according to a compensation method of the pixel circuit 10 shown in fig. 1, and details thereof are not repeated herein.

For example, in step S300, the luminance of the light emitting element EL display is the display luminance Lm.

Some embodiments of the present disclosure also provide a compensation device, and fig. 5 is a schematic block diagram of a compensation device 50 provided in some embodiments of the present disclosure.

As shown in fig. 5, the compensating device 50 includes: control circuit 510, sense voltage detection circuit 520, and compensation voltage acquisition circuit 530. The compensation device 50 is configured to compensate the pixel circuit 60 of the sub-pixel of the display device, the pixel circuit 60 includes a driving circuit 600, the driving circuit 600 includes a control terminal 610 and a first terminal 620, and the first terminal 620 of the driving circuit 600 is configured to be electrically connected to the sensing signal line SEN and the light emitting element EL.

For example, a specific example of the pixel circuit 60 may be the pixel circuit 10 as shown in fig. 2.

The control circuit 510 is configured to control the driving circuit 600 to be turned on to charge the sensing signal line SEN.

For example, the control circuit 510 includes a data driving circuit 511 and a gate driving circuit 512, and the pixel circuit 60 may further include a data writing circuit. The data driving circuit 511 applies a data voltage (for example, the first detection data voltage and the second detection data voltage) to the data writing circuit, and the gate driving circuit 512 applies a scan signal to the data writing circuit to control the data writing circuit to be turned on. When the data writing circuit is turned on, the applied data voltage may be transmitted to the control terminal 610 of the driving circuit 600 to control the driving circuit 600 to be turned on or off, and at the same time, the magnitude of the current flowing through the driving circuit 600 may be controlled.

For example, the data driving circuit 511 and the gate driving circuit 512 may be implemented as semiconductor chips.

The sensing voltage detection circuit 520 is configured to detect a first sensing voltage and a second sensing voltage on the sensing signal line SEN, respectively.

For example, the sensing voltage detection circuit 520 includes the detection circuit 500 shown in fig. 2. The sensing voltage detection circuit 520 may be implemented in various suitable forms, and may include, for example, an amplification sub-circuit that amplifies the voltage detected from the sensing signal line SEN to obtain an amplified voltage signal, an analog-to-digital conversion (ACD) circuit, and the like, which is converted by the analog-to-digital conversion circuit to a digital signal that may be used for subsequent analysis, calculation, and the like.

The compensation voltage obtaining circuit 530 is configured to obtain a voltage of the control terminal 610 of the driving circuit 600 as a first compensation data voltage in a case where the first sensing voltage is equal to a first pre-stored sensing voltage; and acquiring the voltage of the control terminal 610 of the driving circuit 600 as a second compensation data voltage under the condition that the second sensing voltage is equal to a second pre-stored sensing voltage, wherein the first compensation data voltage and the second compensation data voltage are used for the display compensation operation of the pixel circuit 60, the first pre-stored sensing voltage corresponds to a first initial optical compensation parameter written into the control terminal 610 of the driving circuit 600 under the condition that the light emitting element EL displays a first brightness, the second pre-stored sensing voltage corresponds to a second initial optical compensation parameter written into the control terminal 610 of the driving circuit 600 under the condition that the light emitting element EL displays a second brightness, and the first brightness is different from the second brightness.

For example, as shown in fig. 5, the compensation voltage obtaining circuit 530 is electrically connected to the control terminal 610 of the driving circuit 600.

For example, as shown in fig. 5, the compensation device 50 further includes a compensation parameter updating circuit 540. The compensation parameter update circuit 540 is configured to update a value of a first optical compensation parameter in the compensation data voltage lookup table using the first compensation data voltage, and update a value of a second optical compensation parameter in the compensation data voltage lookup table using the second compensation data voltage, wherein the initial value of the first optical compensation parameter is a first initial optical compensation parameter, and the initial value of the second optical compensation parameter is a second initial optical compensation parameter.

For example, the compensation parameter updating circuit 540 is further configured to calculate a plurality of display compensation data voltages in a case where the light emitting element EL displays a plurality of luminances, based on the first optical compensation parameter and the second optical compensation parameter.

For example, the compensation parameter updating circuit 540 may include a calculation sub-circuit for calculating a plurality of display compensation data voltages in the case where the light emitting element EL displays a plurality of luminances. The calculation sub-circuit may be implemented using a hardware circuit. The computation sub-circuit may be formed using, for example, resistors, capacitors, and amplifiers. The calculating sub-circuit can also be realized by signal processors such as FPGA, DSP, MCU, etc. The computing sub-circuit may include, for example, a processor and a memory, the processor executing a software program stored in the memory to perform the function of computing the plurality of display compensation data voltages.

It should be noted that, for the specific operations performed by the compensation parameter updating circuit 540, reference may be made to the above-mentioned related descriptions of step S30 and step S40 of the compensation method shown in fig. 1, and no further description is given here.

At least one embodiment of the present disclosure further provides a display device including the compensation device, the pixel circuit and the sensing signal line according to any one of the embodiments of the present disclosure, for example, the compensation device 50, the pixel circuit 60 and the sensing signal line SEN shown in fig. 5 may be included. For example, the compensation device 50 is electrically connected to the pixel circuit 60 and the sensing signal line SEN, respectively.

Fig. 6 is a schematic diagram of a display device 70 according to some embodiments of the present disclosure. As shown in fig. 6, the display device 70 includes a plurality of sub-pixels P (i.e., pixel units) arranged in an array, each of the sub-pixels P including a pixel circuit 60.

For example, as shown in fig. 6, the data driving circuit 511 applies a data voltage (for example, the first detection data voltage and the second detection data voltage described above) to the pixel circuit 60 in each sub-pixel P, and the gate driving circuit 512 applies a scanning signal to the pixel circuit 60 in each sub-pixel P.

For example, as shown in fig. 6, the display device 70 may further include a timing controller 710. The timing controller 710 is used to process image data RGB input from the outside of the display device 70, provide the processed image data RGB to the data driving circuit 511, and output a scan control signal GCS and a data control signal DCS to the gate driving circuit 512 and the data driving circuit 511 to control the gate driving circuit 512 and the data driving circuit 511.

For example, the gate driving circuit 512 provides a plurality of gate signals (i.e., scan signals) according to a plurality of scan control signals GCS from the timing controller 710.

For example, the data driving circuit 511 converts digital image data RGB input from the timing controller 710 into data voltages according to a plurality of data control signals DCS originating from the timing controller 710 using reference gamma voltages.

For example, the timing controller 710 processes externally input image data RGB to match the size and resolution of the display device 70, and then supplies the processed image data RGB to the data driving circuit 511. The timing controller 710 generates a plurality of scan control signals GCS and a plurality of data control signals DCS using synchronization signals SYNC (e.g., a dot clock DCLK, a data enable signal DE, a horizontal synchronization signal Hsync, and a vertical synchronization signal Vsync) externally input from the display device 70. The timing controller 710 supplies the generated scan control signal GCS and data control signal DCS to the gate driving circuit 512 and the data driving circuit 511, respectively, for control of the gate driving circuit 512 and the data driving circuit 511.

For example, the display device 70 may further include other components, such as a signal decoding circuit, a voltage conversion circuit, etc., which may be conventional components, for example, and will not be described in detail herein.

For example, the display device 70 may be any product or component having a display function, such as a liquid crystal panel, electronic paper, an OLED panel, a mobile phone, a tablet computer, a television, a display, a notebook computer, a digital photo frame, and a navigator, and the embodiments of the disclosure are not limited thereto.

For example, in a display device provided in at least one embodiment of the present disclosure, the pixel circuit further includes a memory circuit, the driving circuit further includes a second terminal configured to receive a power supply voltage, and the first terminal and the second terminal of the memory circuit are electrically connected to the control terminal and the first terminal of the driving circuit, respectively.

For the present disclosure, there are also the following points to be explained:

(1) the drawings of the embodiments of the disclosure only relate to the structures related to the embodiments of the disclosure, and other structures can refer to the common design.

(2) Thicknesses and dimensions of layers or structures may be exaggerated in the drawings used to describe embodiments of the present invention for clarity. It will be understood that when an element such as a layer, film, region, or substrate is referred to as being "on" or "under" another element, it can be "directly on" or "under" the other element or intervening elements may be present.

(3) Without conflict, embodiments of the present disclosure and features of the embodiments may be combined with each other to arrive at new embodiments.

The above description is only for the specific embodiments of the present disclosure, but the scope of the present disclosure is not limited thereto, and the scope of the present disclosure should be subject to the scope of the claims.

Claims

1. A compensation method of a pixel circuit, wherein the pixel circuit comprises a drive circuit, the drive circuit comprises a control terminal and a first terminal, the first terminal of the drive circuit is configured to be electrically connected with a sensing signal line and a light-emitting element,

the compensation method comprises the following steps:

controlling the drive circuit to be conducted to charge the sensing signal line, and acquiring the voltage of a control end of the drive circuit as a first compensation data voltage under the condition that a first sensing voltage on the sensing signal line is equal to a first pre-stored sensing voltage;

controlling the drive circuit to be conducted to charge the sensing signal line, and acquiring the voltage of the control end of the drive circuit as a second compensation data voltage under the condition that a second sensing voltage on the sensing signal line is equal to a second pre-stored sensing voltage;

wherein the first compensation data voltage and the second compensation data voltage are used for a display compensation operation of the pixel circuit, the first pre-stored sensing voltage corresponds to a first initial optical compensation parameter written to the control terminal of the driving circuit in a case where the light emitting element displays a first luminance, the second pre-stored sensing voltage corresponds to a second initial optical compensation parameter written to the control terminal of the driving circuit in a case where the light emitting element displays a second luminance, the first luminance is different from the second luminance, wherein the compensation method further comprises: the compensation data voltage look-up table is updated,

wherein the compensation data voltage lookup table includes a first optical compensation parameter and a second optical compensation parameter, an initial value of the first optical compensation parameter is the first initial optical compensation parameter, an initial value of the second optical compensation parameter is the second initial optical compensation parameter, and

updating the compensation data voltage look-up table comprises: updating the value of the first optical compensation parameter using the first compensation data voltage; and updating the value of the second optical compensation parameter using the second compensation data voltage;

the compensation method further comprises the following steps: calculating a plurality of display compensation data voltages in a case where the light emitting element displays a plurality of luminances according to the first optical compensation parameter and the second optical compensation parameter, wherein the plurality of display compensation data voltages are obtained by the following calculation formula:

or

2. A compensation method according to claim 1, wherein the compensation method is performed in a blanking period of one frame time.

3. The compensation method according to claim 1 or 2, wherein acquiring the voltage of the control terminal of the driving circuit as the first compensation data voltage comprises:

adjusting a value of a first detection data voltage written in a control terminal of the driving circuit, so that after the sensing signal line is charged by the driving circuit for a first time, the first sensing voltage on the sensing signal line approaches the first pre-stored sensing voltage, and under the condition that the first sensing voltage on the sensing signal line is equal to the first pre-stored sensing voltage, acquiring the adjusted first detection data voltage as the first compensation data voltage;

acquiring the voltage of the control terminal of the driving circuit as a second compensation data voltage comprises:

and adjusting a value of a second detection data voltage written in a control terminal of the driving circuit, so that after the sensing signal line is charged by the driving circuit for a second time, the second sensing voltage on the sensing signal line approaches the second pre-stored sensing voltage, and under the condition that the second sensing voltage on the sensing signal line is equal to the second pre-stored sensing voltage, acquiring the adjusted second detection data voltage as the second compensation data voltage.

4. A compensation method according to claim 3, wherein the first time and the second time are of the same duration.

5. The compensation method of claim 3, wherein the first compensation data voltage obtained at the Nth frame is used as the first detection data voltage in the (N + 1) th frame,

a second compensation data voltage obtained at the nth frame is used as a second detection data voltage in the (N + 1) th frame, and N is an integer greater than 0;

the first initial optical compensation parameter serves as a first detected data voltage in a first frame, and the second initial optical compensation parameter serves as a second detected data voltage in the first frame.

6. A compensation method according to claim 3, wherein the first and second pre-stored sense voltages are obtained by:

writing the first initial optical compensation parameter into a control end of the driving circuit to enable the driving circuit to be conducted, and after the sensing signal line is charged for the first time through the driving circuit, acquiring the voltage on the sensing signal line as the first pre-stored sensing voltage;

and writing the second initial optical compensation parameter into the control end of the driving circuit to enable the driving circuit to be conducted, and after the sensing signal line is charged by the driving circuit for the second time, acquiring the voltage on the sensing signal line as the second pre-stored sensing voltage.

7. A compensation method according to claim 1 or 2, wherein the first initial optical compensation parameter and the second initial optical compensation parameter are obtained by:

acquiring a voltage written into a control end of the driving circuit as the first initial optical compensation parameter under the condition that the light-emitting element displays the first brightness;

and acquiring the voltage written into the control end of the driving circuit as the second initial optical compensation parameter under the condition that the light-emitting element displays the second brightness.

8. The compensation method according to claim 1 or 2, wherein the first luminance is a maximum luminance of the light emitting element, and the second luminance is 1/4 of the maximum luminance of the light emitting element.

9. A driving method of a pixel circuit, comprising:

determining a display luminance of a light emitting element electrically connected to the pixel circuit;

obtaining a first compensation data voltage and a second compensation data voltage according to the compensation method of any one of claims 1 to 8, and calculating a display compensation data voltage corresponding to the display luminance from the first compensation data voltage and the second compensation data voltage; and

and applying the display compensation data voltage to the pixel circuit to drive the light-emitting element to emit light.

10. A compensation arrangement, comprising: the device comprises a control circuit, a sensing voltage detection circuit and a compensation voltage acquisition circuit;

wherein the compensation device is configured to compensate the pixel circuit, the pixel circuit comprises a driving circuit, the driving circuit comprises a control end and a first end, the first end of the driving circuit is configured to be electrically connected with the sensing signal line and the light-emitting element,

the control circuit is configured to control the drive circuit to conduct to charge the sensing signal line;

the sensing voltage detection circuit is configured to detect a first sensing voltage and a second sensing voltage on the sensing signal line, respectively;

the compensation voltage acquisition circuit is configured to acquire a voltage of a control terminal of the driving circuit as a first compensation data voltage under the condition that the first sensing voltage is equal to a first pre-stored sensing voltage; and acquiring a voltage of a control terminal of the driving circuit as a second compensation data voltage in a case where the second sensing voltage is equal to a second pre-stored sensing voltage,

wherein the first compensation data voltage and the second compensation data voltage are used for a display compensation operation of the pixel circuit, the first pre-stored sensing voltage corresponds to a first initial optical compensation parameter written into the control terminal of the driving circuit under a condition that the light emitting element displays a first brightness, the second pre-stored sensing voltage corresponds to a second initial optical compensation parameter written into the control terminal of the driving circuit under a condition that the light emitting element displays a second brightness, and the first brightness is different from the second brightness; wherein the compensation device further comprises: a compensation parameter update circuit configured to update a value of a first optical compensation parameter in a compensation data voltage lookup table using the first compensation data voltage and update a value of a second optical compensation parameter in the compensation data voltage lookup table using the second compensation data voltage,

wherein the initial value of the first optical compensation parameter is the first initial optical compensation parameter, and the initial value of the second optical compensation parameter is the second initial optical compensation parameter;

the device compensation parameter update circuit is further configured to calculate a plurality of display compensation data voltages in a case where the light emitting element displays a plurality of luminances, based on the first optical compensation parameter and the second optical compensation parameter,

wherein the plurality of display compensation data voltages are obtained by the following calculation formula:

or

，

Wherein Vm is an mth display compensation data voltage among the plurality of display compensation data voltages, V1 is the first optical compensation parameter, V2 is the second optical compensation parameter, L1 is the first luminance, L2 is the second luminance, Lm is a luminance parameter corresponding to the mth display compensation data voltage, and M is a positive integer.

11. A display device comprising the compensation device according to claim 10, the pixel circuit, and the sensing signal line,

wherein the compensation device is electrically connected with the pixel circuit and the sensing signal line, respectively.

12. The display device according to claim 11, wherein the pixel circuit further comprises a data writing circuit,

the data writing circuit is electrically connected with the control end of the driving circuit and is configured to be conducted in a data writing process so as to write data voltage into the control end of the driving circuit.

13. The display device according to claim 11, wherein the pixel circuit further comprises a sensing circuit,

a first end of the sensing circuit is electrically connected with the sensing signal line, a second end of the sensing circuit is electrically connected with the first end of the driving circuit and the light emitting element,

the sensing circuit is configured to be turned on during data writing to write a reference voltage to the first terminal of the driving circuit, and to be turned on during detection to charge the sensing signal line.

14. The display device according to claim 11, wherein the pixel circuit further comprises a storage circuit,

the driver circuit further includes a second terminal configured to receive a supply voltage,

the first end and the second end of the storage circuit are respectively and electrically connected with the control end and the first end of the driving circuit.