Pixel compensation circuit and method and display device

Abstract

The invention provides a pixel compensation circuit and method and a display device, and belongs to the technical field of display. In the pixel compensation circuit, the sensing circuit can sense and output the electric signal reflecting the temperature of the light-emitting device, the sampling circuit can sample and output the real-time driving signal output to the light-emitting device by the pixel circuit when the temperature is determined to be abnormal based on the electric signal, and the compensation circuit can compensate the data signal based on the real-time driving signal. Therefore, the purpose of compensating the light-emitting driving signal output by the pixel circuit to the light-emitting device based on the data signal can be achieved, the influence of temperature abnormity on the light-emitting driving signal is avoided, normal light emitting of the light-emitting device can be ensured, and the display effect of the display panel is good.

Description

Technical Field

[0001] The present application relates to the field of display technology, and in particular to a pixel compensation circuit and method, and a display device. Background Art

[0002] As a new generation of display devices, organic light emitting diodes (OLEDs) are increasingly being used in display, lighting, and information technology (IT) fields. A display panel including OLEDs is also called an OLED display panel.

[0003] In the related art, an OLED display panel generally includes: a substrate, and a plurality of pixels located on the substrate. Each pixel includes a pixel circuit and a light-emitting device (i.e., an OLED). The pixel circuit includes a data writing transistor and a driving transistor. The data writing transistor is used to output a data signal to the driving transistor; the driving transistor is used to output a driving current to the light-emitting device based on the data signal to drive the light-emitting device to emit light.

[0004] However, tests have found that as the temperature of the light-emitting device increases, due to the large differences in the characteristics of the transistor at different temperatures, the driving current output by the pixel circuit to the light-emitting device will become abnormal, which in turn will cause the light-emitting device to emit abnormal light, resulting in poor display effect of the display panel. Summary of the invention

[0005] A pixel compensation circuit and method, and a display device are provided, which can solve the problem of poor display effect of a display panel due to abnormal temperature in the related art. The technical solution is as follows:

[0006] On the one hand, a pixel compensation circuit is provided, which is used to compensate for a light-emitting driving signal transmitted by a pixel circuit to a light-emitting device based on a data signal provided by a data terminal; the pixel compensation circuit comprises: a sensing circuit, a sampling circuit and a compensation circuit, the sensing circuit is located at one side of the light-emitting device and connected to the sampling circuit, the sampling circuit is also connected to the compensation circuit and is used to be connected to the light-emitting device, and the compensation circuit is also connected to the data terminal;

[0007] The sensing circuit is used to: sense the device temperature of the light emitting device, and output a target electrical signal reflecting the device temperature based on the device temperature;

[0008] The sampling circuit is used to: when the target electrical signal does not meet the electrical signal reference value, sample and output the real-time driving signal transmitted by the pixel circuit to the light-emitting device, and the electrical signal reference value is an electrical signal reflecting the device temperature of the light-emitting device when the light-emitting device emits normal brightness;

[0009] The compensation circuit is used to compensate the data signal provided by the data terminal based on the real-time driving signal, so as to compensate the light-emitting driving signal transmitted by the pixel circuit to the light-emitting device.

[0010] Optionally, the driving signals in the real-time driving signal and the light-emitting driving signal are both driving currents flowing through the light-emitting device, and the pixel circuit is used to generate the driving current based on the data signal; and the compensation circuit is used to:

[0011] Inputting the real-time driving current output by the sampling circuit and the real-time luminous brightness of the light-emitting device driven by the real-time driving current into the training model to obtain a feedback voltage;

[0012] Using the feedback voltage to compensate for the voltage of the data signal;

[0013] Among them, the training model is a model obtained by training based on a sample set, and the sample set includes a one-to-one corresponding multiple input parameters and a plurality of output parameters, each of the input parameters includes a real driving current flowing through the light-emitting device and the real luminous brightness of the light-emitting device driven by the real driving current, and each of the output parameters includes a feedback voltage required to generate the real driving current, and the one-to-one corresponding multiple input parameters and multiple output parameters are parameters of the light-emitting device that change over time at a fixed brightness in different multiple display panels.

[0014] Optionally, the pixel circuit is further used to drive the light-emitting device to emit light based on a light-emitting control signal provided by a light-emitting control terminal; the sensing circuit is also connected to the light-emitting control terminal;

[0015] Furthermore, the sensing circuit is used to sense a device temperature of the light emitting device in response to the light emitting control signal, and output a target electrical signal reflecting the device temperature based on the device temperature.

[0016] Optionally, the sensing circuit includes: a sensing unit and a reading unit; the sensing unit is located at one side of the light emitting device and is respectively connected to the light emitting control terminal and the reading unit, and the reading unit is also respectively connected to the power supply terminal, the light emitting control terminal and the sampling circuit;

[0017] The sensing unit is used to: sense the device temperature of the light emitting device in response to the light emitting control signal, and output a control electrical signal based on the device temperature;

[0018] The reading unit is used to: respond to the light emitting control signal and the control electrical signal, and output the target electrical signal based on the power supply signal provided by the power supply terminal.

[0019] Optionally, the pixel circuit and the light-emitting device are located on one side of a substrate and are stacked in sequence in a direction away from the substrate;

[0020] The sensing unit includes: a first electrode, a thermosensitive material layer, and a second electrode located between the pixel circuit and the light-emitting device and stacked in sequence in a direction close to the light-emitting device, wherein the first electrode is connected to the light-emitting control end, and the second electrode is connected to the reading unit.

[0021] Optionally, the reading unit is integrated with the pixel circuit;

[0022] The sampling circuit and the compensation circuit are integrated on a processing chip independent of the substrate, and the second electrode in the sensing unit is connected to the processing chip through a flexible circuit board.

[0023] Optionally, the reading unit includes: a first switch unit and a second switch unit;

[0024] The first switch part is connected to the sensing unit, the power supply end and the second switch part respectively, and the second switch part is also connected to the light emitting control end and the sampling circuit respectively;

[0025] The first switch unit is used to: control the connection and disconnection between the power supply terminal and the second switch unit in response to the reference electrical signal;

[0026] The second switch unit is used to control the on-off of the first switch unit and the sampling circuit in response to the light emission control signal, and output the target electrical signal.

[0027] Optionally, the first switch unit includes: a first transistor; the second light-opening unit includes: a second transistor; and the first transistor and the second transistor are of different types;

[0028] The gate of the first transistor is connected to the sensing unit, the first electrode of the first transistor is connected to the power supply terminal, the second electrode of the first transistor is connected to the first electrode of the second transistor, the gate of the second transistor is connected to the light emitting control terminal, and the second electrode of the second transistor is connected to the sampling circuit.

[0029] Optionally, the sampling circuit comprises: a comparison unit and a sampling unit; the comparison unit is respectively connected to the reference end, the sensing circuit and the sampling unit, the sampling unit is also connected to the compensation circuit and is used to be connected to the light-emitting device, and the reference end is used to provide the reference value of the electrical signal;

[0030] The comparison unit is used to compare the target electrical signal with the electrical signal reference value, and output a sampling enable signal when it is determined that the target electrical signal is greater than the electrical signal reference value;

[0031] The sampling unit is used to sample and output a real-time driving signal transmitted from the pixel circuit to the light-emitting device in response to the sampling enable signal.

[0032] Optionally, the comparison unit includes: a comparator, a first resistor and a second resistor;

[0033] Of the positive phase input and the negative phase input of the comparator, one input is connected to the sensing circuit through the first resistor, the other input is connected to the reference terminal through the second resistor, and the output of the comparator is connected to the sampling unit.

[0034] Optionally, the sampling unit comprises: an amplifier, a capacitor and a switch;

[0035] The positive phase input terminal of the amplifier is used to be connected to the light emitting device, the negative phase input terminal of the amplifier is grounded, and the output terminal of the amplifier is connected to the compensation circuit;

[0036] The capacitor is connected between the positive phase input terminal and the negative phase input terminal of the amplifier;

[0037] The switch is connected between the positive phase input terminal and the negative phase input terminal of the amplifier, and is also connected to the comparison unit.

[0038] Optionally, the real-time driving signal outputted from the output end of the amplifier is an analog signal, and the signal processed by the compensation circuit is a digital signal;

[0039] The sampling unit further includes an analog-to-digital converter connected between the output end of the amplifier and the compensation circuit, wherein the analog-to-digital converter is used to convert the real-time driving signal in the form of an analog signal output by the amplifier into a digital signal and then output it to the compensation circuit.

[0040] Optionally, the sampling unit comprises: a controller and at least one sampling transistor;

[0041] The controller is connected to the comparison unit, the at least one sampling transistor is respectively connected to the scan switch end and the sensing line, and is also used to connect to the light emitting device, the scan switch end is connected to the controller, and the sensing line is connected to the compensation circuit.

[0042] On the other hand, a pixel compensation method is provided, which is used to compensate for a light-emitting driving signal transmitted by a pixel circuit to a light-emitting device based on a data signal provided by a data terminal, and is applied to the pixel compensation circuit as described in the above aspect; the method comprises:

[0043] sensing a device temperature of the light emitting device through a sensing circuit in the pixel compensation circuit, and outputting a target electrical signal reflecting the device temperature based on the device temperature through the sensing circuit;

[0044] When the target electrical signal does not meet the electrical signal reference value, the sampling circuit in the pixel compensation circuit samples and outputs a real-time driving signal transmitted by the pixel circuit to the light-emitting device, wherein the electrical signal reference value is an electrical signal reflecting the device temperature of the light-emitting device when the light-emitting device emits normal brightness;

[0045] The data signal provided by the data terminal is compensated based on the real-time driving signal by the compensation circuit in the pixel compensation circuit to compensate the light-emitting driving signal transmitted by the pixel circuit to the light-emitting device.

[0046] In another aspect, a display device is provided, the display device comprising: a display panel, a pixel circuit and a light-emitting device located on the display panel, and the pixel compensation circuit as described in the above aspect;

[0047] The pixel circuit is used to transmit a light-emitting driving signal to the light-emitting device based on a data signal provided by the data terminal;

[0048] The pixel compensation circuit is used to compensate for the influence of temperature on the light-emitting driving signal.

[0049] In summary, the beneficial effects brought about by the technical solution provided by the embodiments of the present application may at least include:

[0050] A pixel compensation circuit and method, and a display device are provided. In the pixel compensation circuit, a sensing circuit can sense and output an electrical signal reflecting the temperature of a light-emitting device, and a sampling circuit can sample and output a real-time driving signal output by the pixel circuit to the light-emitting device when a temperature abnormality is determined based on the electrical signal, and the compensation circuit can compensate a data signal based on the real-time driving signal, thereby achieving the purpose of compensating the light-emitting driving signal output by the pixel circuit to the light-emitting device based on the data signal, avoiding the influence of the temperature abnormality on the light-emitting driving signal, thereby ensuring that the light-emitting device emits light normally, and making the display effect of the display panel better. BRIEF DESCRIPTION OF THE DRAWINGS

[0051] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0052] Figure 1 is a structural schematic diagram of a pixel compensation circuit provided in an embodiment of the present application;

[0053] Figure 2 is a structural schematic diagram of another pixel compensation circuit provided in an embodiment of the present application;

[0054] Figure 3 is a structural schematic diagram of another pixel compensation circuit provided in an embodiment of the present application;

[0055] Figure 4 is a structural schematic diagram of another pixel compensation circuit provided in an embodiment of the present application;

[0056] Figure 5 It is a schematic diagram of a film structure of a pixel compensation circuit provided in an embodiment of the present application;

[0057] Figure 6 is a schematic diagram of a membrane structure of a sensing unit provided in an embodiment of the present application;

[0058] Figure 7 is a structural schematic diagram of a reading unit provided in an embodiment of the present application;

[0059] Figure 8 is a schematic diagram of a circuit structure of a reading unit provided in an embodiment of the present application;

[0060] Fig. 9 is a schematic diagram of a circuit structure of a comparison unit provided in an embodiment of the present application;

[0061] Fig.10 is a schematic diagram of a circuit structure of a sampling unit provided in an embodiment of the present application;

[0062] Fig.11 This is a schematic diagram of the relationship between luminous brightness and luminous current provided in an embodiment of the present application;

[0063] Fig.12 is a schematic diagram of the circuit structure of another sampling unit provided in an embodiment of the present application;

[0064] Fig.13 is Fig.12 A timing diagram of a circuit operation shown on the basis;

[0065] Fig.14 It is a flowchart of a pixel compensation method provided in an embodiment of the present application;

[0066] Fig.15 is a schematic diagram of a working process of a compensation circuit provided in an embodiment of the present application;

[0067] Fig.16 It is a structural schematic diagram of a display device provided in an embodiment of the present application. DETAILED DESCRIPTION

[0068] In order to make the objectives, technical solutions and advantages of the present application clearer, the implementation methods of the present application will be further described in detail below with reference to the accompanying drawings.

[0069] It should be noted that the transistors used in the embodiments of the present application can be thin film transistors (TFT) or field effect transistors or other devices with the same characteristics. For example, the field effect transistor can be a metal-oxide semiconductor (MOS) field effect transistor, also known as a MOS tube. In addition, according to the role in the circuit, the transistors used in the embodiments of the present application are mainly switching transistors. In the embodiments of the present application, the source electrode can be referred to as the first electrode and the drain electrode can be referred to as the second electrode. According to the form in the accompanying drawings, the middle end of the transistor is defined as the control electrode, which can also be referred to as the gate electrode, the signal input end is the source electrode, and the signal output end is the drain electrode. In addition, the switching transistors used in the embodiments of the present application can include any one of a P-type transistor and an N-type transistor, wherein the P-type transistor is turned on when the gate is at a low potential and is turned off when the gate is at a high potential; the N-type transistor is turned on when the gate is at a high potential and is turned off when the gate is at a low potential. In addition, multiple signals in each embodiment of the present application correspond to a first potential and a second potential. The first potential and the second potential only represent that the potential of the signal has two state quantities, and do not mean that the first potential or the second potential has a specific value in the full text.

[0070] With the continuous advancement of small and medium-sized technology development and industrial application, as well as the continuous research of large-size technology and integrated processes, higher requirements are put forward for the display border, refresh rate, power consumption and display quality of OLED products. At present, the backplane driving circuits in the OLED display panels on the market mainly use LTPS and LTPO backplane driving circuits. Among them, LTPS refers to a circuit made of low-temperature polycrystalline silicon (LTPS) material; LTPO refers to a circuit made of low-temperature polycrystalline oxide (LTPO) material; here refers to the transistors in the preparation circuit, and the active layer material of the transistor can be LTPS or LTPO. However, considering the high power consumption and large leakage current of the LTPS backplane driving circuit, and the limitations of the LTPO backplane driving circuit in terms of flicker and variable refresh rate (VRR), the full Oxide backplane driving technology layout circuit has begun to be used, and the full Oxide means that the transistors in the circuit are made of oxide Oxide material.

[0071] However, the full oxide backplane driving technology verification project found that when the OLED display panel is displayed in a high-brightness and high-grayscale scene for a long time, the overall temperature of the panel will rise, and as the temperature rises, the display brightness under the high grayscale will also be abnormal, such as the display brightness rises. Among them, high brightness is, for example, a brightness greater than or equal to 500 nits (nit). After technical and process analysis, it was found that this phenomenon is mainly due to the fact that the characteristics of the transistors included in the pixel circuit of the display panel are quite different at different temperatures, resulting in abnormal driving current (also called light-emitting current) transmitted to the OLED light-emitting device, which in turn leads to abnormal display caused by abnormal light-emitting brightness of the OLED light-emitting device. The characteristics of the transistor are, for example, threshold voltage and / or mobility. Based on this, an embodiment of the present application provides a pixel compensation circuit, which can compensate for the influence of temperature on the light-emitting current and solve the problem of abnormal brightness increase due to temperature increase.

[0072] Figure 1 1 is a schematic diagram of a pixel compensation circuit provided in an embodiment of the present application. The pixel compensation circuit can be used to compensate for a light-emitting driving signal transmitted by the pixel circuit P1 to the light-emitting device L1 based on a data signal provided by the data terminal Vdata.

[0073] For example, the light emitting device L1 may be an OLED, and reference Figure 1, the pixel circuit P1 can be connected to the pull-up power supply terminal ELVDD, the data terminal Vdata and the anode of the light-emitting device L1 respectively, and the cathode of the light-emitting device L1 can be connected to the pull-down power supply terminal ELVSS. The pixel circuit P1 can output a light-emitting drive signal to the light-emitting device L1 based on the power signal provided by the pull-up power supply terminal ELVDD and the data signal provided by the data terminal Vdata. The light-emitting device L1 can emit light based on the light-emitting drive signal and the power signal provided by the pull-down power supply terminal ELVSS. The structure including the pixel circuit P1 and the light-emitting device L1 can also be called a pixel. The display panel can generally include multiple pixels.

[0074] Under the influence of temperature, the driving current transmitted from the pixel circuit P1 to the light emitting device L1 may be abnormal, which may cause abnormal brightness of the light emitting device L1 and finally cause abnormal display brightness of the display panel, affecting the display effect.

[0075] Continue to refer Figure 1 The pixel compensation circuit 00 described in the embodiment of the present application includes: a sensing circuit 01, a sampling circuit 02 and a compensation circuit 03.

[0076] The sensing circuit 01 is located at one side of the light emitting device L1 and is connected to the sampling circuit 02. The sampling circuit 02 is also connected to the compensation circuit 03 and is used to connect to the light emitting device L1. The compensation circuit 03 is also connected to the data terminal Vdata. Optionally, the sampling circuit 02 can be connected to the anode of the light emitting device L1. It is understandable that Figure 1 The positional relationship between the sensing circuit 01 and the light emitting device L1 is not shown.

[0077] The sensing circuit 01 is used to sense the device temperature of the light emitting device L1 and output a target electrical signal reflecting the device temperature based on the device temperature.

[0078] For example, the sensing circuit 01 may include a temperature sensing device for sensing the device temperature of the light emitting device L1 and outputting a current signal that is positively correlated with the device temperature. That is, the target electrical signal may be a current signal, and the higher the device temperature, the greater the current value, and the lower the device temperature, the smaller the current value. In this way, the temperature of the display panel at different time points can be distinguished.

[0079] The sampling circuit 02 is used to sample and output a real-time driving signal transmitted from the pixel circuit P1 to the light-emitting device L1 when the target electrical signal does not meet the electrical signal reference value.

[0080] For example, after receiving the target electrical signal reflecting the device temperature output by the sensing circuit 01, the sampling circuit 02 can determine whether the target electrical signal meets the electrical signal reference value by comparing the target electrical signal with the electrical signal reference value, and when it is determined that the target electrical signal does not meet the electrical signal reference value, it can re-sample the real-time driving signal transmitted by the pixel circuit P1 to the light-emitting device L1, such as sampling the real-time driving current used to drive the light-emitting device L1 to emit light, that is, the driving current flowing through the light-emitting device L1.

[0081] Among them, the electric signal reference value is an electric signal reflecting the device temperature of the light-emitting device L1 when the light-emitting device L1 emits normal brightness. That is, the electric signal reference value can be the electric signal output by the sensing circuit 01 at the device temperature when the light-emitting device L1 emits normal brightness. In addition, the electric signal reference value can be pre-stored in the sampling circuit 02 for easy call when used. Of course, the electric signal reference value can also be flexibly adjusted in real time. On this basis, the sampling circuit 02 can determine that the device temperature is abnormal when it is determined that the target electric signal reflecting the device temperature exceeds (that is, greater than) the electric signal reference value, and start sampling the real-time drive signal transmitted by the pixel circuit P1 to the light-emitting device L1. Correspondingly, it can also be known that when the device temperature is normal, the sampling circuit 02 may not work. Therefore, the sampling circuit 02 can timely sample and output the real-time drive signal transmitted by the pixel circuit P1 to the light-emitting device L1 when the device temperature is high, and the working power consumption is low.

[0082] Of course, in some embodiments, the sampling circuit 02 may further sample the real-time driving signal transmitted from the pixel circuit P1 to the light-emitting device L1 only when the target electrical signals output by the sensing circuit 01 in multiple different time periods do not meet the electrical signal reference value. In this way, the sampling reliability can be ensured and the power consumption can be further reduced. Alternatively, the sampling circuit 02 may also sample the real-time driving signal in real time.

[0083] Furthermore, in some embodiments, the electrical signal reference value may also be a range determined at different temperatures. When the sampling circuit 02 determines that the target electrical signal reflecting the device temperature is not within the range and is greater than the upper limit of the range, it may determine that the device temperature is abnormal and start sampling the real-time drive signal transmitted by the pixel circuit P1 to the light-emitting device L1.

[0084] The compensation circuit 03 is used to compensate the data signal provided by the data terminal Vdata based on the real-time driving signal, so as to compensate the light-emitting driving signal transmitted by the pixel circuit P1 to the light-emitting device L1.

[0085] Optionally, after receiving the real-time driving signal output by the sampling circuit 02 when the device temperature is abnormal, the compensation circuit 03 can compensate the voltage of the data signal based on the real-time driving signal, so as to further compensate the light-emitting driving signal output by the pixel circuit P1 to the light-emitting device L1 based on the data signal, thereby avoiding the influence of the temperature abnormality on the light-emitting driving signal, and then reliably driving the light-emitting device L1 to emit light normally.

[0086] In summary, the embodiment of the present application provides a pixel compensation circuit. In the pixel compensation circuit, the sensing circuit can sense and output an electrical signal reflecting the temperature of the light-emitting device, and the sampling circuit can sample and output a real-time driving signal output by the pixel circuit to the light-emitting device when the temperature is abnormal based on the electrical signal, and the compensation circuit can compensate the data signal based on the real-time driving signal, so as to achieve the purpose of compensating the light-emitting driving signal output by the pixel circuit to the light-emitting device based on the data signal, avoid the influence of the temperature abnormality on the light-emitting driving signal, thereby ensuring that the light-emitting device emits light normally, so that the display effect of the display panel is better.

[0087] Optionally, as described in the above embodiment, whether it is a real-time driving signal collected by a sampling circuit or a light-emitting driving signal output by a pixel circuit, the driving signal may refer to a driving current flowing through the light-emitting device L1, and the pixel circuit P1 may be used to generate the driving current based on a data signal. Accordingly, the real-time driving signal is also called a real-time driving current, and the light-emitting driving signal is also called a light-emitting driving current. Since both the real-time driving current and the light-emitting driving current are currents used to drive the light-emitting device L1 to emit light, they are also called light-emitting currents.

[0088] On this basis, the compensation circuit 03 can be used to: input the real-time driving current output by the sampling circuit 02 and the real-time luminous brightness of the light-emitting device L1 driven by the real-time driving current into the training model, obtain a feedback voltage, and then use the feedback voltage to compensate for the voltage of the data signal.

[0089] The training model may be a model obtained by training based on a sample set. The sample set may include a plurality of input parameters and a plurality of output parameters corresponding to each other. Each input parameter may include a real driving current flowing through the light-emitting device L1 and a real luminous brightness of the light-emitting device L1 driven by the real driving current, and each output parameter may include a feedback voltage required to generate the real driving current, and the plurality of input parameters and the plurality of output parameters corresponding to each other may be parameters of the light-emitting device L1 changing over time at a fixed brightness (or specific brightness) in different display panels.

[0090] That is, in the embodiment of the present application, first, the compensation circuit 03 can obtain the real luminous brightness, luminous current and required feedback voltage of several (i.e., multiple) display panels that change over time at a specific brightness. Among them, the real luminous brightness, luminous current and feedback voltage are used as a sample set, and the real luminous brightness and luminous current are used as input parameters in the sample set, and the required feedback voltage is used as an output parameter. Then, the compensation circuit 03 can train the sample set through an algorithm, and establish a functional relationship model between the feedback voltage and the real luminous brightness and luminous current as a training model.

[0091] Optionally, the algorithm may be, for example, a neural network algorithm. The neural network algorithm has self-learning capability, and by training the sample set through the neural network algorithm, the obtained functional relationship model can have self-learning capability. When the actual luminous brightness and luminous current of the display panel are input into the functional relationship model, the corresponding feedback voltage can be calculated through the self-learning capability of the functional relationship model. In addition, the neural network algorithm also has high-speed solving capability, so the above-mentioned functional relationship model can solve the exposure time at high speed, thereby improving the calculation rate of the functional relationship model. Of course, it is not limited to the neural network algorithm.

[0092] On this basis, the compensation circuit 03 can directly input the real-time driving current output by the sampling circuit 02 and the corresponding real-time luminous brightness into the established functional relationship model, so as to quickly and accurately obtain the feedback voltage required for compensation of the current real-time driving current. After obtaining the feedback voltage, the compensation circuit 03 can further use the feedback voltage to compensate the voltage of the data signal, thereby further compensating the luminous driving current output by the pixel circuit P1 to the light-emitting device L1, offsetting the abnormal luminous driving current caused by the abnormal temperature rise, thereby maintaining the normal brightness display of the display panel.

[0093] Optionally, the plurality of display panels may be display panels of the same model, for example, they may be display panels of the same model produced in the same batch or different batches. Furthermore, the increase in the brightness of the plurality of display panels over time at a specific brightness causes the luminous current to change, resulting in different actual luminous brightness, and the corresponding feedback voltages are different. The luminous current and feedback voltage of each display panel at the actual luminous brightness are taken as a sample, and the luminous current and feedback voltage of the plurality of display panels at the actual luminous brightness are taken as a set of samples, constituting the sample set recorded in the above embodiment. In addition, it can be understood that the more the number of display panels, the more samples in the sample set, and accordingly, the more accurate the functional relationship model obtained by training.

[0094] Optionally, Figure 2 is a schematic diagram of the structure of another pixel compensation circuit provided by an embodiment of the present application. Figure 2As shown, the pixel circuit P1 can also be used to drive the light emitting device L1 to emit light based on a light emitting control signal provided by the light emitting control terminal EM.

[0095] For example, the pixel circuit P1 may regenerate the light-emitting driving signal when the potential of the light-emitting control signal is the first potential, and may not generate the light-emitting driving signal when the potential of the light-emitting control signal is the second potential. And / or, the pixel circuit P1 may transmit the light-emitting driving signal to the light-emitting device L1 to drive the light-emitting device L1 to emit light when the potential of the light-emitting control signal is the first potential, and may not transmit the light-emitting driving signal to the light-emitting device L1 to drive the light-emitting device L1 to emit light when the potential of the light-emitting control signal is the second potential.

[0096] Optionally, in the embodiment of the present application, the first potential may refer to an effective potential, the second potential may refer to an invalid potential, and the first potential may be a low potential relative to the second potential, that is, the first potential may be a low potential, and the second potential may be a high potential; of course, in some other embodiments, the first potential may also be a high potential relative to the second potential. This is related to the type of transistor connected to the light emitting control terminal EM in the pixel circuit P1.

[0097] On this basis, continue to refer to Figure 2 It can be seen that the sensing circuit 01 can also be connected to the light emitting control terminal EM. In addition, the sensing circuit 01 can be used to: sense the device temperature of the light emitting device L1 in response to the light emitting control signal, and output a target electrical signal reflecting the device temperature based on the device temperature.

[0098] For example, with the pixel circuit P1, the sensing circuit 01 may also sense the device temperature of the light-emitting device L1 and output a target electrical signal when the potential of the light-emitting control signal is the first potential, that is, when the light-emitting device L1 emits light. Also, when the potential of the light-emitting control signal is the second potential, that is, when the light-emitting device L1 does not emit light, the sensing circuit 01 may not work and not sense the device temperature. In this way, the sensing circuit 01 may work only when it is necessary to sense the device temperature, thereby ensuring reliable sensing of the device temperature while reducing the operating power consumption of the sensing circuit 01. Furthermore, the target electrical signal may be, for example, a current signal.

[0099] Optionally, continue to refer to Figure 2 It can be seen that the sensing circuit 01 may include: a sensing unit 011 and a reading unit 012 .

[0100] The sensing unit 011 may be located at one side of the light emitting device L1 and may be connected to the light emitting control terminal EM and the reading unit 012 respectively. The reading unit 012 may also be connected to the power supply terminal, the light emitting control terminal EM and the sampling circuit 02 respectively. Figure 2The positional relationship between the sensing unit 011 and the light emitting device L1 is also not shown.

[0101] The power supply terminal may be, for example, a pull-up power supply terminal ELVDD connected to the pixel circuit P1. In this way, wiring can be simplified and costs can be saved. Of course, in some other embodiments, the power supply terminal may also be another power supply terminal independent of the pull-up power supply terminal ELVDD.

[0102] The sensing unit 011 may be used to sense the device temperature of the light emitting device L1 in response to the light emitting control signal, and output a control electrical signal based on the device temperature.

[0103] For example, the sensing unit 011 can sense the device temperature of the light emitting device L1 when the potential of the light emitting control signal is a first potential, and output a control electrical signal based on the device temperature; and the sensing unit 011 can stop sensing the device temperature of the light emitting device L1 when the potential of the light emitting control signal is a second potential. Furthermore, the control electrical signal output by the sensing unit 011 can be an alternating current signal generated based on temperature changes.

[0104] The reading unit 012 may be configured to output a target electrical signal in response to the light emitting control signal and the control electrical signal and based on the power supply signal provided by the power supply terminal.

[0105] For example, the reading unit 012 can output a target electrical signal based on a power supply signal provided by a power supply terminal (e.g., ELVDD) when the potential of the light-emitting control signal is a first potential and the potential of the control electrical signal is also a first potential; and the reading unit 012 can stop outputting the target electrical signal when the potential of the light-emitting control signal and / or the potential of the control electrical signal is a second potential.

[0106] That is, the sensing unit 011 and the reading unit 012 may cooperate with each other to sense and output a target electrical signal that can reflect the temperature of the device.

[0107] Optionally, Figure 3 is a schematic diagram of the structure of another pixel compensation circuit provided in an embodiment of the present application. Figure 3 As shown, the sampling circuit 02 may include: a comparing unit 021 and a sampling unit 022 .

[0108] The comparison unit 021 can be connected to the reference terminal V0, the sensing circuit 01 and the sampling unit 022 respectively, the sampling unit 022 can also be connected to the compensation circuit 03 and can be used to connect to the light emitting device L1, and the reference terminal V0 can be used to provide an electrical signal reference value. In addition, in combination with the above description, the comparison unit 021 can be connected to the reading unit 012 in the sensing circuit 01, and the sampling unit 022 can be connected to the anode of the light emitting device L1.

[0109] The comparison unit 021 may be used to compare the target electrical signal with the electrical signal reference value, and output a sampling enable signal when it is determined that the target electrical signal is greater than the electrical signal reference value.

[0110] That is, the situation in which the target electrical signal does not meet the electrical signal reference value described above may mean that the target electrical signal is greater than the electrical signal reference value, indicating that the temperature of the device is abnormally increased. The comparison unit 021 can determine whether the target electrical signal is greater than the electrical signal reference value by comparing the target electrical signal with the electrical signal reference value, and can output a sampling enable signal when it is determined that the target electrical signal is greater than the electrical signal reference value, and stop outputting the sampling enable signal or output a disable signal when it is determined that the target electrical signal is not greater than the electrical signal reference value.

[0111] Optionally, the potential of the sampling enable signal and the potential of the disable signal may be exactly opposite. For example, the potential of the sampling enable signal may be a high potential 1, while the potential of the disable signal may be a low potential 0.

[0112] The sampling unit 022 may be used to: in response to a sampling enable signal, sample and output a real-time driving signal transmitted from the pixel circuit P1 to the light emitting device L1 .

[0113] That is, the sampling unit 022 can start sampling the real-time drive signal transmitted by the pixel circuit P1 to the light-emitting device L1 and output the real-time drive signal when it receives the sampling enable signal output by the comparison unit 021 (indicating that the target electrical signal is greater than the electrical signal reference value and the device temperature has risen abnormally), and will not work when it does not receive the sampling enable signal output by the comparison unit 021 or receives the disable signal output by the comparison unit 021 (indicating that the target electrical signal is not greater than the electrical signal reference value and the device temperature is normal).

[0114] In other words, the comparison unit 021 and the sampling unit 022 may cooperate with each other to sample and output a real-time driving signal transmitted from the pixel circuit P1 to the light emitting device L1 , such as sampling a driving current flowing through the light emitting device L1 .

[0115] Combining the previous records and Figure 4 It can be seen that the pixel compensation circuit provided in the embodiment of the present application may include the following five modules: a temperature device (corresponding to the sensing unit 011), a reading module (corresponding to the reading unit 012), a comparison module (corresponding to the comparison unit 021), an extraction module (corresponding to the sampling unit 022) and a voltage compensation module (corresponding to the compensation circuit 03).

[0116] First, the temperature device can detect the temperature of the display panel at different times, which may refer to the device temperature of the light-emitting device L1 in the display panel, and convert the sensed device temperature into a corresponding electrical signal. Then, the reading module can read the electrical signal from the temperature device. Then, the comparison module can compare the signal read by the reading module with the preset electrical signal reference value, and when it is determined that the signal read by the reading module does not meet the electrical signal reference value, that is, when it is determined that the temperature is abnormally increased, an enable signal is provided to the extraction module. After that, the extraction module can extract the current value flowing through the light-emitting device in response to the received enable signal, and output the extracted current value to the voltage compensation module. Finally, the voltage compensation module can calculate the feedback voltage for compensation based on the received current value through the established functional relationship model of the feedback voltage, the actual luminous brightness and the luminous current, and use the feedback voltage to compensate the voltage of the data signal, thereby further compensating the luminous drive current output by the pixel circuit to the light-emitting device, so as to offset the influence of the temperature abnormality on the luminous drive current, and ensure that the light-emitting device can emit light normally.

[0117] Optionally, combined Figure 1 and Figure 4 It can also be seen that the pixel circuit P1 in the pixel may include a driving transistor, and the driving transistor may be connected to the data terminal Vdata and the light-emitting device L1 in the pixel, respectively, to output a light-emitting driving signal to the light-emitting device L1 based on the data signal provided by the data terminal Vdata, so as to drive the light-emitting device L1 to emit light. Of course, in addition to the driving transistor, other transistors may also be included, such as a data writing transistor, a light-emitting control transistor, and a reset transistor, etc., which are not limited in the embodiments of the present application.

[0118] Optionally, Figure 5 It is a schematic diagram of the film layer structure of a pixel compensation circuit provided in an embodiment of the present application. Figure 6 It is a schematic diagram of the membrane structure of the sensing unit.

[0119] refer to Figure 5 It can be seen that the pixel circuit P1 and the light emitting device L1 may be located on one side of the substrate 10 and may be stacked in sequence in a direction away from the substrate 10 .

[0120] Combination Figure 5 and Figure 6 It can be seen that the sensing unit 011 may include: a first electrode 0111, a thermosensitive material layer 0112, and a second electrode 0113, which are located between the pixel circuit P1 and the light emitting device L1 and are sequentially stacked in a direction close to the light emitting device L1. Figure 2 In the sensing unit 011 , the first electrode 0111 may be connected to the light emitting control terminal EM, and the second electrode 0113 may be connected to the reading unit 012 .

[0121] That is, the sensing unit 011 as a temperature device may include two electrodes and a thermosensitive material layer 0112 located between the two electrodes. Furthermore, a light emitting control signal may be loaded on the first electrode 0111 of the two electrodes, and the thermosensitive material layer 0113 may sense the temperature change of the light emitting device L1 under the control of the light emitting control signal and generate an alternating current signal, which may be output as a control electrical signal to the reading unit 012 as a reading module through the second electrode 0113.

[0122] Optionally, continue to refer to Figure 5 It can be seen that the reading unit 012 and the pixel circuit P1 can be integrated. The sampling circuit 02 and the compensation circuit 03 can be integrated on a processing chip independent of the substrate 10, and the second electrode 0113 in the sensing unit 011 can be connected to the processing chip 2 through the flexible circuit board 1.

[0123] That is, the pixel circuit P1 may include a reading unit 012 as a reading module, and may be located on one side of the substrate 10, the sensing unit 011 as a temperature device may be located on the side of the pixel circuit P1 away from the substrate 10, the light emitting device L1 may be located on the side of the sensing unit 011 away from the substrate 10, and the comparison unit 021 as a comparison module, the sampling unit 022 as an extraction module, and the compensation circuit 03 as a voltage compensation module may all be integrated on a separate processing chip 2, and connected to other circuits through a flexible circuit board 1. The display panel of this structure has a simple structure and a compact layout, which is conducive to the improvement of resolution and the narrow frame design. Of course, it is not limited to Figure 6 For example, in some other embodiments, the reading unit 012 and the pixel circuit P1 may be independent of each other, and the reading unit 012 may be located between the pixel circuit P1 and the sensing unit 011. Also, the circuit is not limited to being connected using a flexible circuit board.

[0124] Optionally, Figure 7 012 is a schematic diagram of the structure of a reading unit 012 provided in an embodiment of the present application. Figure 7 As shown, the reading unit 012 includes: a first switch part 0121 and a second switch part 0122 .

[0125] The first switch unit 0121 can be connected to the sensing unit 011, the power supply terminal (eg, ELVDD) and the second switch unit 0122 respectively, and the second switch unit 0122 can also be connected to the light emitting control terminal EM and the sampling circuit 02 respectively. Figure 3 The second switch unit 0122 may be connected to the comparison unit 021 in the sampling circuit 02 .

[0126] The first switch unit 0121 can be used to control the connection and disconnection between the power supply terminal and the second switch unit 0122 in response to a reference electrical signal.

[0127] For example, the first switch unit 0121 can control the power supply terminal ELVDD and the second switch unit 0122 to be turned on when the potential of the reference electrical signal is the first potential, so that the power signal provided by the power supply terminal ELVDD can be transmitted to the second switch unit 0122; and the first switch unit 0121 can control the power supply terminal ELVDD to be disconnected from the second switch unit 0122 when the potential of the reference electrical signal is the second potential.

[0128] The second switch unit 0122 can be used to control the on-off of the first switch unit 0121 and the sampling circuit 02 in response to the light emitting control signal, and output a target electrical signal.

[0129] For example, when the potential of the light-emitting control signal is the first potential, the second switch unit 0122 can control the first switch unit 0121 to be connected with the comparison unit 021 in the sampling circuit 02, and at the same time generate a target electrical signal based on the received power supply signal; and when the potential of the light-emitting control signal is the second potential, the second switch unit 0122 can control the first switch unit 0121 to be disconnected from the comparison unit 021 in the sampling circuit 02.

[0130] Optionally, in Figure 7 Based on the reference Figure 8 It can be seen that the first switch unit 0121 may include: a first transistor T01. The second light-opening unit 0122 may include: a second transistor T02. And the types of the first transistor T01 and the second transistor T02 may be different. Figure 8 , the first transistor T01 shown is an N-channel transistor (i.e., an N-type transistor), and the second transistor T02 is a P-channel transistor (i.e., a P-type transistor). Of course, in some other embodiments, the first transistor T01 may also be a P-type transistor, and the second transistor T02 may also be an N-type transistor.

[0131] Among them, the gate of the first transistor T01 can be connected to the sensing unit 011 as a temperature device, the first electrode of the first transistor T01 can be connected to the power supply terminal ELVDD, the second electrode of the first transistor T01 can be connected to the first electrode of the second transistor T02, the gate of the second transistor T02 can be connected to the light emitting control terminal EM, and the second electrode of the second transistor T02 can be connected to the sampling circuit 02. Combined with the above description, the second electrode of the second transistor T02 can be connected to the comparison unit 021 as a comparison module in the sampling circuit 02.

[0132] On this basis, it can be known that the gate of the first transistor T01 can receive a reference electrical signal output from the sensing unit 011 as a temperature device, and can be turned on or off under the control of the reference electrical signal. Also, since the energy generated by different temperatures is different, the strength of the electrical signal written into the gate of the first transistor T01 by the temperature device is different, and accordingly, the degree of opening of the first transistor T01 is different. Furthermore, the current of the second pole of the second transistor T02 is different. In this way, different temperature conditions at different time points can be distinguished by the signal output by the second pole of the second transistor T02.

[0133] Optionally, Fig. 9 021 is a schematic diagram of the structure of a comparison unit 021 provided in an embodiment of the present application. Fig. 9 As shown, the comparison unit 021 may include: a comparator Comp, a first resistor R1 and a second resistor R2. The first resistor R1 and the second resistor R2 may serve the purpose of current limiting.

[0134] Of the positive input terminal + and the negative input terminal - of the comparator Comp, one input terminal may be connected to the sensing circuit 01 through the first resistor R1, and the other input terminal may be connected to the reference terminal V0 through the second resistor R2, and the output terminal OUT0 of the comparator Comp may be connected to the sampling unit 022. In addition, in combination with the foregoing description, the comparator Comp here may be connected to the reading unit 012 in the sensing circuit 01.

[0135] On this basis, combined with Figure 8 The comparator Comp can receive the signal output from the second electrode of the second transistor T02, and decide whether to send a sampling enable signal to the sampling unit 022 as an extraction module based on the received signal. As described above, the comparator Comp can output a sampling enable signal to prompt the sampling unit 022 to extract the driving current flowing through the light-emitting device L1 when the received signal is greater than the electrical signal reference value.

[0136] Furthermore, based on the working principle of the comparator Comp, it can be known that on the basis that the positive phase input terminal + is connected to the reading unit 012 in the sensing circuit 01 to receive the target electrical signal, and the negative phase input terminal - is connected to the reference terminal V0 to receive the electrical signal reference value, the comparator Comp can output a sampling enable signal of a high potential 1 through the output terminal OUT0 when the target electrical signal is greater than the electrical signal reference value provided by the reference terminal V0. On the basis that the positive phase input terminal + is connected to the reference terminal V0 to receive the electrical signal reference value, and the negative phase input terminal - is connected to the reading unit 012 in the sensing circuit 01 to receive the target electrical signal, the comparator Comp can output a sampling enable signal of a low potential 1 through the output terminal OUT0 when the target electrical signal is greater than the electrical signal reference value provided by the reference terminal V0. For example, referring to Fig. 9, the negative input terminal - (marked as A) of the comparator Comp is connected to the reference terminal V0, and the positive input terminal + (marked as B) is connected to the reading unit 012 in the sensing circuit 01.

[0137] In addition, reference Fig. 9 It can also be seen that the comparator Comp can also be connected to the positive power terminal V+ and the negative power terminal V− respectively to operate based on the power signals provided by the positive power terminal V+ and the negative power terminal V−.

[0138] Optionally, the comparator Comp may be a hysteresis comparator with strong working stability and strong anti-interference capability.

[0139] Optionally, as an optional implementation: Fig.10 As shown, the sampling unit 022 may include: an amplifier OP-Amp, a capacitor Cfb, and a switch Cint.

[0140] The positive input terminal + of the amplifier OP-Amp can be used to connect to the light emitting device L1 (not shown in the figure), the negative input terminal - of the amplifier OP-Amp can be grounded, and the output terminal OUT1 of the amplifier OP-Amp can be connected to the compensation circuit 03.

[0141] The capacitor Cfb may be connected between the positive phase input terminal + and the negative phase input terminal - of the amplifier OP-Amp.

[0142] The switch Cint may be connected between the positive phase input terminal + and the negative phase input terminal − of the amplifier OP-Amp, and may also be connected to the comparison unit 021 .

[0143] On this basis, when the comparison unit 021 outputs the sampling enable signal, the switch Cint included in the sampling unit 022 can be disconnected, the amplifier OP-Amp can work, and sample the real-time driving signal transmitted from the pixel circuit P1 to the light-emitting device L1, and after amplifying the real-time driving signal, output it to the compensation circuit 03 through the output terminal OUT1. In this way, it can be ensured that the real-time driving signal is reliably sampled and output to the compensation circuit 03. When the comparison unit 021 stops outputting the sampling enable signal or outputs the disable signal, the switch Cint included in the sampling unit 022 can be closed, and the amplifier OP-Amp can stop working, that is, stop sampling the real-time driving signal.

[0144] It can be understood that the real-time driving signal outputted by the output terminal OUT1 of the amplifier OP-Amp is generally an analog signal, while the signal that can be processed by the compensation circuit 03 is a digital signal.

[0145] Accordingly, continue to refer to Fig.10It can be seen that the sampling unit 022 may also include an analog-to-digital converter (ADC) connected between the output terminal OUT1 of the amplifier OP-Amp and the compensation circuit 03. The analog-to-digital converter ADC may be used to convert the real-time driving signal in the form of an analog signal output by the amplifier OP-Amp into a digital signal and then output it to the compensation circuit 03 for reliable processing by the compensation circuit 03. Fig.10 The output end of the analog-to-digital converter ADC is marked as OUT2.

[0146] exist Fig.10 Based on the structure, combined Fig.11 It can be seen that the driver chip of the display panel can switch different brightness by controlling the grayscale, so that the sampling unit 022 detects the driving current flowing through the light emitting device L1, that is, extracts the corresponding current signal for modeling the compensation circuit 03. The driver chip is similar to the host or computer of the display panel. Fig.11 In the figure, the horizontal axis refers to the voltage Vdata of the data signal, the vertical axis refers to the driving current Current, and Gray refers to the gray scale. Fig.11 It is used to indicate the driving current generated under the voltage of different data signals, and the display gray scale corresponding to the generated driving current, which is expressed as the luminous brightness.

[0147] Alternatively, as another optional implementation, such as Fig.12 As shown, the sampling unit 022 may include: a controller ( Fig.12 not shown) and at least one sampling transistor.

[0148] The controller can be connected to the comparison unit 021, at least one sampling transistor can be connected to the scan switch terminal Scan and the sensing line Sensing respectively, and is also used to be connected to the light-emitting device L1 (here it can refer to the anode of the light-emitting device L1), the scan switch terminal Scan can be connected to the controller, and the sensing line Sensing can be connected to the compensation circuit 03.

[0149] For example, Fig.12 The at least one sampling transistor shown in the figure may include: a transistor T7. The gate of the transistor T7 may be connected to the scan switch terminal Scan5, and the transistor T7 may be indirectly connected to the anode of the light emitting device L1 through the transistors T4 and T2 in the pixel. The compensation circuit 03 may include a digital-to-analog converter (DAC). The controller may be the driving chip described above. In addition, reference Fig.12It can also be seen that the pixel circuit in the pixel may include transistors T1 to T6, T8 and a storage capacitor C1. Among them, the gates of transistors T1 to T4 can be connected to the scan switch terminals Scan1 to Scan4 respectively, the gate of transistor T5 can be connected to the light emitting control terminal EM, the gate of transistor T8 is connected to the scan switch terminal Scan6, the first electrode of transistor T3 can be connected to the reference signal terminal Vref, the first electrode of transistor T5 can be connected to the pull-up power supply terminal ELVDD, and the first electrode of transistor T8 can be connected to the data terminal Vdata. Transistor T6 is the driving transistor described above. The connection between each transistor and the connection method of the storage capacitor can be referred to. Fig.12 , I will not go into details here. And Fig.12 The connection point between the transistor T6 and the anode of the light emitting device L1 is identified as a node (Node) A.

[0150] Optionally, Fig.12 Each transistor shown may be an N-type transistor. Alternatively, in some other embodiments, each transistor may be a P-type transistor. Alternatively, it may include a P-type transistor and an N-type transistor. Fig.12 The structure shown in Fig.12 Each transistor shown is an N-type transistor, and the effective potential is a high potential relative to the invalid potential. Fig.13 A circuit timing diagram is shown.

[0151] Combination Fig.13 It can be seen that in the t01 stage, the scan switch terminals Scan1 to Scan4 can provide a high-potential scan switch signal, so that the transistors T1 to T4 are all turned on, and then the reference signal provided by the reference signal terminal Vref can be transmitted to the gate of the transistor T6 through the turned-on transistors T3, T4 and T1 in sequence, and then transmitted to the node A through the transistors T3 and T2 in sequence, so as to reset the gate of the transistor T6 and the anode of the light-emitting device L1. Accordingly, the t01 stage can also be called a reset stage.

[0152] In phase t02, the scan switch terminals Scan1 and Scan6 can provide a high-potential scan switch signal, so that both transistors T8 and T1 are turned on, and then the data signal provided by the DAC to the data terminal Vdata can be transmitted to the gate of the transistor T6 through the turned-on transistors T8 and T1 in sequence, so as to charge the gate of the transistor T6. Accordingly, phase t02 can also be called a data writing phase.

[0153] In the t03 stage, the light emitting control terminal EM can provide a high potential light emitting control signal to turn on the transistor T5, thereby forming a path between the pull-up power terminal ELVDD and the pull-down power terminal ELVSS, thereby lighting up the light emitting device L1. Accordingly, the t03 stage can also be called a light emitting stage.

[0154] In the t04 stage, the light-emitting control terminal EM can continue to provide a high-potential light-emitting control signal to light up the light-emitting device L1. At the same time, the scanning switch terminals Scan2, Scan4 and Scan5 can provide high-potential scanning switch signals to turn on the transistors T2, T4 and T7, so that the current at the node A can be transmitted to the sensing line Sensing through the turned-on transistors T2, T4 and T7 in sequence as a real-time driving signal, and output to the compensation circuit 03 through the sensing line Sensing to complete the detection sampling. Correspondingly, the t04 stage can also be called the sensing stage. The current at the node A is the light-emitting driving current flowing through the light-emitting device L1. Afterwards, the compensation circuit 03 can determine the feedback voltage based on the received real-time driving signal, and use the feedback voltage to compensate the voltage of the data signal provided by the data terminal Vdata, that is, give the feedback voltage to the data terminal Vdata. Of course, in some other embodiments, the t04 stage and the t03 stage can be executed simultaneously.

[0155] In combination with the above description, it can be known that the controller can control the scan switch terminals Scan2, Scan4 and Scan5 to provide a scan switch signal with a valid potential (e.g., a high potential) when receiving the sampling enable signal output by the comparison unit 021, so that the transistors T2, T4 and T7 are all turned on. When the controller receives that the comparison unit 021 stops outputting the sampling enable signal or outputs a disable signal, the controller can control the scan switch terminals Scan2, Scan4 and Scan5 to provide a scan switch signal with an invalid potential (e.g., a low potential), so that the transistors T2, T4 and T7 are all turned off, thereby causing the sampling unit 022 to stop sampling the real-time drive signal.

[0156] It is understandable that the above circuit division method is only a schematic illustration. For example, in some other embodiments, the transistors T2, T4 and T7 can also be divided into the sampling unit 022, that is, the sampling unit 022 can include three sampling transistors. And the compensation circuit 03 does not only include Fig.12The DAC shown. The compensation circuit 03 may also include some other circuits, such as a processor. The training model described above can be established in the processor, and the compensation action described above can be completed: the real-time driving current output by the sampling circuit 02 and the real-time luminous brightness of the light-emitting device L1 driven by the real-time driving current are input into the training model to obtain a feedback voltage, and then the feedback voltage is used to compensate the voltage of the data signal. The DAC is used to convert the compensated data signal from a digital signal to an analog signal, and then drive the pixel circuit to work.

[0157] Based on the above description, it can be known that the embodiment of the present application provides a pixel compensation circuit. The circuit includes five modules, namely, a sensing unit 011 as a temperature device, a reading unit 012 as a reading module, a comparison unit 021 as a comparison module, an extraction module as a sampling unit 022, and a voltage compensation module as a compensation circuit 03.

[0158] Among them, the temperature device and the reading module can be integrated with the pixel circuit and arranged on the substrate, and can be compatible with the light control signal provided by the light control terminal EM received by the pixel circuit. When the light emitting device L1 emits light, that is, when the display panel emits light, the first electrode 0111 of the temperature device and the second transistor T02 in the reading module can load the light control signal. When the potential of the light control signal is an effective potential, the second transistor T02 can be turned on, and the temperature device can sense the device temperature of the light emitting device L1. When the temperature remains unchanged, the first transistor T01 in the reading module is turned off, and the light driving current flowing through the light emitting device L1 is not sampled. As the display time of the display panel increases, the surface temperature of the light emitting device L1 gradually rises. At this time, the temperature change will cause the temperature device to generate an alternating current signal, thereby controlling the first transistor T01 to turn on. In addition, since the energy of different temperatures is different, the signal strength written into the first transistor T01 is also different, so the degree of opening of the first transistor T01 can be different, and the second pole output current of the second transistor T02 is different, thereby achieving the purpose of distinguishing the temperature conditions at different time points.

[0159] Next, the signal output by the second pole of the second transistor T02 passes through the comparison module, and the comparison module can compare the signal with the set value (i.e., the electrical signal reference value). Once it is determined that the signal is not within the set value range, such as greater than the electrical signal reference value, a sampling enable signal is output to the extraction module. The sampling enable signal can trigger the extraction module to extract the light-emitting drive current flowing through the light-emitting device L1. And, it can be understood that the comparison module can, for example, be the comparator described above, and the positive input terminal or negative input terminal of the comparator can receive the set value. When the positive input terminal of the comparator receives the set value, a high-potential sampling enable signal is output; when the negative input terminal of the comparator receives the set value, a low-potential sampling enable signal is output. And, the comparator can, for example, be the hysteresis comparator described above.

[0160] Afterwards, the extraction module can extract the light-emitting driving current value output by the pixel circuit P1 to the light-emitting device L1 under the control of the sampling enable signal. That is, the extraction module can have the functions of a current sensor and a voltage sensor. Finally, the voltage compensation module can calculate the compensation value for feedback of the actual light-emitting brightness based on the established functional relationship model between the feedback voltage and the actual light-emitting brightness and the light-emitting current, offset the change in the light-emitting current caused by the abnormal temperature rise, and thus maintain the normal brightness display of the display panel.

[0161] In summary, the embodiment of the present application provides a pixel compensation circuit. In the pixel compensation circuit, the sensing circuit can sense and output an electrical signal reflecting the temperature of the light-emitting device, and the sampling circuit can sample and output a real-time driving signal output by the pixel circuit to the light-emitting device when the temperature is abnormal based on the electrical signal, and the compensation circuit can compensate the data signal based on the real-time driving signal, so as to achieve the purpose of compensating the light-emitting driving signal output by the pixel circuit to the light-emitting device based on the data signal, avoid the influence of the temperature abnormality on the light-emitting driving signal, thereby ensuring that the light-emitting device emits light normally, so that the display effect of the display panel is better.

[0162] The present application also provides a pixel compensation method, which can be used to compensate for the light-emitting drive signal transmitted by the pixel circuit to the light-emitting device based on the data signal provided by the data terminal, and can be applied to the pixel compensation circuit described in the above embodiment. Fig.14 As shown, the method includes:

[0163] Step 1401: sense the device temperature of the light-emitting device through a sensing circuit in a pixel compensation circuit, and output a target electrical signal reflecting the device temperature based on the device temperature through the sensing circuit.

[0164] Step 1402: When the target electrical signal does not meet the electrical signal reference value, the sampling circuit in the pixel compensation circuit samples and outputs a real-time driving signal transmitted by the pixel circuit to the light-emitting device.

[0165] The electrical signal reference value is an electrical signal reflecting the device temperature of the light emitting device when the light emitting device emits normal brightness.

[0166] Step 1403: Compensate the data signal provided by the data terminal based on the real-time driving signal by the compensation circuit in the pixel compensation circuit to compensate for the light-emitting driving signal transmitted by the pixel circuit to the light-emitting device.

[0167] Optionally, combined Figure 4 As previously recorded, Fig.15 A compensation method flow chart of a compensation circuit is also shown. Fig.15 It can be seen that the method may include:

[0168] Step 1501: obtain the actual luminance, luminous current and required feedback voltage of several display panels at a specific brightness, and use the actual luminance, luminous current and feedback voltage as a sample set.

[0169] Optionally, as described above, several display panels may be display panels of the same model, for example, they may be display panels of the same model produced in the same batch or different batches. The temperature rise of several display panels over time at a specific brightness may cause the luminous current to change, resulting in different real luminous brightness, and correspondingly, the feedback voltage required for compensation is different. On this basis, the luminous current and feedback voltage of each display panel at the real luminous brightness can be taken as a sample. Furthermore, the luminous current and feedback voltage of several display panels at the real luminous brightness can be taken as a set of samples to constitute a sample set of the real luminous brightness, luminous current and feedback voltage of the display panel. Of course, the more the number of display panels, the more samples in the sample set, and the more accurate the functional relationship model obtained in the training.

[0170] Step 1502: Using the actual luminous brightness and luminous current as input parameters and the feedback voltage as output parameter, the samples are trained to establish a functional relationship model between the feedback voltage that varies with time and the actual luminous brightness and luminous current.

[0171] Optionally, as described above, the sample set can be divided into an input sample set and an output sample set. Among them, the real luminous brightness and luminous current can be used as the input sample set, and the corresponding feedback voltage can be used as the output sample set. Then, by training the input sample set and the output sample set, a functional relationship model between the feedback voltage of the display panel and the real luminous brightness and luminous current can be obtained, and the establishment of a functional relationship model between the feedback voltage of the display brightness of the display panel and the real luminous brightness and luminous current of the display panel is completed.

[0172] For example, training the sample set may refer to: training the sample set by using a neural network algorithm.

[0173] Step 1503: The extraction module obtains the actual luminous brightness and luminous current of the display panel at a certain time point, and calculates the feedback voltage of the display panel at the time point based on the functional relationship model.

[0174] Optionally, as described above, after the functional relationship model is established, the luminous current and the corresponding luminous brightness output by the sampling unit of the extraction module at a certain time point can be input into the functional relationship model to quickly and accurately obtain the feedback voltage of the display panel at that time point.

[0175] Step 1504: Feedback the calculated feedback voltage to the data voltage for compensation.

[0176] Finally, the compensation circuit serving as a voltage compensation module can feed back the calculated feedback voltage to the voltage of the data signal (also called data voltage) to compensate for the data voltage, thereby further compensating for the light-emitting driving signal (such as light-emitting current) output by the pixel circuit to the light-emitting device, thereby solving the problem of abnormal light-emitting current causing abnormal light-emitting of the display panel.

[0177] It is understandable that, since the pixel compensation method and the aforementioned pixel compensation circuit have substantially the same technical effects, for the purpose of brevity, the technical effects of the pixel compensation method will not be repeatedly described herein.

[0178] The present application also provides a display device. Fig.16 As shown, the display device includes: a display panel 000, a pixel circuit P1 and a light emitting device L1 located on the display panel 000, and a pixel compensation circuit 00 as described in the above embodiment.

[0179] The pixel circuit P1 is used to transmit a light-emitting driving signal to the light-emitting device L1 based on a data signal provided by the data terminal Vdata; the pixel compensation circuit 00 is used to compensate for the influence of temperature on the light-emitting driving signal.

[0180] The structure including the pixel circuit P1 and the light emitting device L1 can be called a pixel. Fig.16 It can also be seen that the display panel may include a plurality of pixels arranged in an array.

[0181] It is understandable that, since the display device and the aforementioned pixel compensation circuit have substantially the same technical effects, the technical effects of the display device will not be described repeatedly herein for the purpose of brevity.

[0182] Optionally, the display device may be an OLED display device, and the display device may be any appropriate display device, including but not limited to any product or component with a display function, such as a mobile phone, a tablet computer, a television, a monitor, a notebook computer, a digital photo frame, a navigator, and an e-book.

[0183] It should be noted that the terms used in the implementation methods of this application are only used to explain the embodiments of this application, and are not intended to limit this application. Unless otherwise defined, the technical terms or scientific terms used in the implementation methods of this application should be the common meanings understood by people with general skills in the field to which this application belongs.

[0184] For example, the words "first", "second", "third" and similar words used in the patent application specification and claims of this application do not indicate any order, quantity or importance, but are only used to distinguish different components. Similarly, words such as "one" or "a" do not indicate a quantity limitation, but indicate the existence of at least one. Words such as "include" or "comprise" and similar words mean that the elements or objects appearing before "include" or "comprise" include the elements or objects listed after "include" or "comprise" and their equivalents, and do not exclude other elements or objects. Words such as "connect" or "connected" and similar words are not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect. "Up", "down", "left", "right", etc. are only used to indicate relative positional relationships. When the absolute position of the described object changes, the relative positional relationship may also change accordingly. "And / or" means that there can be three relationships. For example, A and / or B can represent: A exists alone, A and B exist at the same time, and B exists alone. The character " / " generally indicates that the objects associated with each other are in an "or" relationship.

[0185] The above description is only an optional embodiment of the present application and is not intended to limit the present application. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present application shall be included in the protection scope of the present application.

Claims

1. A pixel compensation circuit, characterized in that: Used to compensate for the light-emitting driving signal transmitted by the pixel circuit to the light-emitting device based on the data signal provided by the data terminal; The pixel compensation circuit includes: a sensing circuit, a sampling circuit and a compensation circuit, wherein the sensing circuit is located at one side of the light emitting device and connected to the sampling circuit, the sampling circuit is also connected to the compensation circuit and is used to be connected to the light emitting device, and the compensation circuit is also connected to the data terminal; The sensing circuit is used to: sense the device temperature of the light emitting device, and output a target electrical signal reflecting the device temperature based on the device temperature; The sampling circuit is used to: when the target electrical signal does not meet the electrical signal reference value, sample and output the real-time driving signal transmitted by the pixel circuit to the light-emitting device, and the electrical signal reference value is an electrical signal reflecting the device temperature of the light-emitting device when the light-emitting device emits normal brightness; The compensation circuit is used to compensate the data signal provided by the data terminal based on the real-time driving signal, so as to compensate the light-emitting driving signal transmitted by the pixel circuit to the light-emitting device.

2. The pixel compensation circuit according to claim 1, characterized in that: The driving signals in the real-time driving signal and the light-emitting driving signal are both driving currents flowing through the light-emitting device, and the pixel circuit is used to generate the driving current based on the data signal; the compensation circuit is used to: Inputting the real-time driving current output by the sampling circuit and the real-time luminous brightness of the light-emitting device driven by the real-time driving current into the training model to obtain a feedback voltage; Using the feedback voltage to compensate for the voltage of the data signal; Among them, the training model is a model obtained by training based on a sample set, and the sample set includes a one-to-one corresponding multiple input parameters and a plurality of output parameters, each of the input parameters includes a real driving current flowing through the light-emitting device and the real luminous brightness of the light-emitting device driven by the real driving current, and each of the output parameters includes a feedback voltage required to generate the real driving current, and the one-to-one corresponding multiple input parameters and multiple output parameters are parameters of the light-emitting device that change over time at a fixed brightness in different multiple display panels.

3. The pixel compensation circuit according to claim 1 or 2, characterized in that: The pixel circuit is also used to drive the light-emitting device to emit light based on a light-emitting control signal provided by the light-emitting control terminal; the sensing circuit is also connected to the light-emitting control terminal; Furthermore, the sensing circuit is used to sense a device temperature of the light emitting device in response to the light emitting control signal, and output a target electrical signal reflecting the device temperature based on the device temperature.

4. The pixel compensation circuit according to claim 3, characterized in that: The sensing circuit comprises: a sensing unit and a reading unit; the sensing unit is located at one side of the light emitting device and is respectively connected to the light emitting control terminal and the reading unit, and the reading unit is also respectively connected to the power supply terminal, the light emitting control terminal and the sampling circuit; The sensing unit is used to: sense the device temperature of the light emitting device in response to the light emitting control signal, and output a control electrical signal based on the device temperature; The reading unit is used to: respond to the light emitting control signal and the control electrical signal, and output the target electrical signal based on the power supply signal provided by the power supply terminal.

5. The pixel compensation circuit according to claim 4, characterized in that: The pixel circuit and the light emitting device are located on one side of the substrate and are stacked in sequence in a direction away from the substrate; The sensing unit includes: a first electrode, a thermosensitive material layer, and a second electrode located between the pixel circuit and the light-emitting device and stacked in sequence in a direction close to the light-emitting device, wherein the first electrode is connected to the light-emitting control end, and the second electrode is connected to the reading unit.

6. The pixel compensation circuit according to claim 4, characterized in that: The reading unit is integrated with the pixel circuit; The sampling circuit and the compensation circuit are integrated on a processing chip independent of the substrate, and the second electrode in the sensing unit is connected to the processing chip through a flexible circuit board.

7. The pixel compensation circuit according to claim 4, characterized in that: The reading unit includes: a first switch portion and a second switch portion; The first switch part is connected to the sensing unit, the power supply end and the second switch part respectively, and the second switch part is also connected to the light emitting control end and the sampling circuit respectively; The first switch unit is used to: control the connection and disconnection between the power supply terminal and the second switch unit in response to the reference electrical signal; The second switch unit is used to control the on-off of the first switch unit and the sampling circuit in response to the light emission control signal, and output the target electrical signal.

8. The pixel compensation circuit according to claim 7, characterized in that: The first switch unit includes: a first transistor; the second light-opening unit includes: a second transistor; and the first transistor and the second transistor are of different types; The gate of the first transistor is connected to the sensing unit, the first electrode of the first transistor is connected to the power supply terminal, the second electrode of the first transistor is connected to the first electrode of the second transistor, the gate of the second transistor is connected to the light emitting control terminal, and the second electrode of the second transistor is connected to the sampling circuit.

9. The pixel compensation circuit according to claim 1 or 2, characterized in that: The sampling circuit comprises: a comparison unit and a sampling unit; the comparison unit is connected to the reference end, the sensing circuit and the sampling unit respectively, the sampling unit is also connected to the compensation circuit and is used to connect to the light emitting device, and the reference end is used to provide the reference value of the electrical signal; The comparison unit is used to compare the target electrical signal with the electrical signal reference value, and output a sampling enable signal when it is determined that the target electrical signal is greater than the electrical signal reference value; The sampling unit is used to sample and output a real-time driving signal transmitted from the pixel circuit to the light-emitting device in response to the sampling enable signal.

10. The pixel compensation circuit according to claim 9, characterized in that: The comparison unit includes: a comparator, a first resistor and a second resistor; Of the positive phase input and the negative phase input of the comparator, one input is connected to the sensing circuit through the first resistor, the other input is connected to the reference terminal through the second resistor, and the output of the comparator is connected to the sampling unit.

11. The pixel compensation circuit according to claim 9, characterized in that: The sampling unit comprises: an amplifier, a capacitor and a switch; The positive phase input terminal of the amplifier is used to be connected to the light emitting device, the negative phase input terminal of the amplifier is grounded, and the output terminal of the amplifier is connected to the compensation circuit; The capacitor is connected between the positive phase input terminal and the negative phase input terminal of the amplifier; The switch is connected between the positive phase input terminal and the negative phase input terminal of the amplifier, and is also connected to the comparison unit.

12. The pixel compensation circuit according to claim 11, characterized in that: The real-time driving signal outputted from the output end of the amplifier is an analog signal, and the signal processed by the compensation circuit is a digital signal; The sampling unit further includes an analog-to-digital converter connected between the output end of the amplifier and the compensation circuit, wherein the analog-to-digital converter is used to convert the real-time driving signal in the form of an analog signal output by the amplifier into a digital signal and then output it to the compensation circuit.

13. The pixel compensation circuit according to claim 9, characterized in that: The sampling unit includes: a controller and at least one sampling transistor; The controller is connected to the comparison unit, the at least one sampling transistor is respectively connected to the scan switch end and the sensing line, and is also used to connect to the light emitting device, the scan switch end is connected to the controller, and the sensing line is connected to the compensation circuit.

14. A pixel compensation method, characterized in that: The method is used to compensate for the light-emitting driving signal transmitted by the pixel circuit to the light-emitting device based on the data signal provided by the data terminal, and is applied to the pixel compensation circuit according to any one of claims 1 to 13; the method comprises: sensing a device temperature of the light emitting device through a sensing circuit in the pixel compensation circuit, and outputting a target electrical signal reflecting the device temperature based on the device temperature through the sensing circuit; When the target electrical signal does not meet the electrical signal reference value, the sampling circuit in the pixel compensation circuit samples and outputs a real-time driving signal transmitted by the pixel circuit to the light-emitting device, wherein the electrical signal reference value is an electrical signal reflecting the device temperature of the light-emitting device when the light-emitting device emits normal brightness; The data signal provided by the data terminal is compensated based on the real-time driving signal by the compensation circuit in the pixel compensation circuit to compensate the light-emitting driving signal transmitted by the pixel circuit to the light-emitting device.

15. A display device, characterized in that: The display device comprises: a display panel, a pixel circuit and a light-emitting device located on the display panel, and a pixel compensation circuit according to any one of claims 1 to 13; The pixel circuit is used to transmit a light-emitting driving signal to the light-emitting device based on a data signal provided by the data terminal; The pixel compensation circuit is used to compensate for the influence of temperature on the light-emitting driving signal.

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