Display panel, temperature detection method thereof, and display device

Abstract

The present invention discloses a display panel, a temperature detection method thereof, and a display device. The display panel includes: sub-pixels; the sub-pixels include: a pixel driving circuit, a light-emitting device, and a temperature detection module. An output end of the pixel driving circuit is connected to the light-emitting device, and the pixel driving circuit is configured to drive the light-emitting device to emit light; a temperature detection module for detecting the temperature of the sub-pixel, the temperature detection module including a first transistor; the first transistor is connected to the output end of the pixel driving circuit, and an off-state current of the first transistor represents the temperature of the sub-pixel. Embodiments of the present invention can detect the temperature of the sub-pixel without additionally increasing a film layer structure and without changing the driving mode of the sub-pixel, so as to provide temperature parameters for temperature compensation of the sub-pixel.

Description

Technical Field

[0001] The present invention relates to the field of display technologies, and in particular, to a display panel, a temperature detection method thereof, and a display device. Background Art

[0002] Organic Light Emitting Diode (OLED) display panels have become one of the research focuses of display panels in recent years due to their advantages such as fast response time, light weight, and high contrast. However, the electrical characteristics of OLED devices are temperature-dependent, and the luminous efficiency of OLED devices is different at different temperatures, resulting in differences in the display quality of each sub-pixel in the display panel at different temperatures. Therefore, when the operating temperature of each sub-pixel in the display panel deviates from the preset operating temperature, there will be a problem of distorted display effect of the panel.

[0003] In the prior art, the above problems are usually solved by detecting the temperature of the display panel and compensating the driving current of each sub-pixel according to the detected temperature of the display panel. Among them, temperature detection is the key step of this solution. In the prior art, the temperature is detected by adding a temperature sensor layer in the display panel; or a temperature detection stage is added during the driving process of the sub-pixel, a preset driving signal is applied to the sub-pixel, and the operating temperature of the sub-pixel is analyzed according to the driving current of the sub-pixel under the preset driving signal. Therefore, the temperature detection scheme in the prior art either needs to add a sensor-related film layer, which has a complex process and is not conducive to the thinning and lightening of the display panel; or needs to increase the driving process of the sub-pixel, which has a complex control logic and affects the refresh rate of the display panel. Summary of the Invention

[0004] The present invention provides a display panel, a temperature detection method thereof, and a display device. Without additionally increasing the film layer structure and without changing the sub-pixel driving mode, the temperature of the sub-pixel is detected to provide temperature parameters for the temperature compensation of the sub-pixel.

[0005] To achieve the above technical objectives, the embodiments of the present invention provide the following technical solutions:

[0006] A display panel includes: sub-pixels; the sub-pixels include:

[0007] a pixel driving circuit and a light-emitting device; an output end of the pixel driving circuit is connected to the light-emitting device, and the pixel driving circuit is configured to drive the light-emitting device to emit light;

[0008] a temperature detection module configured to detect the temperature of the sub-pixel, the temperature detection module includes a first transistor; the first transistor is connected to the output end of the pixel driving circuit, and the off-state current of the first transistor represents the temperature of the sub-pixel.

[0009] Optionally, the first transistor is further configured to transmit a compensation current to the light-emitting device.

[0010] Optionally, the display panel further includes: a data line; the data line is electrically connected to the pixel driving circuit and is configured to transmit a data signal to the pixel driving circuit;

[0011] The compensation current is determined according to the temperature of the sub-pixel and the data signal.

[0012] Optionally, the first transistor is turned off during the non-light-emitting stage of the sub-pixel and is turned on during the light-emitting stage of the sub-pixel.

[0013] Optionally, the display panel further includes: a data line; the data line is electrically connected to the pixel driving current and is configured to transmit a data signal to the pixel driving circuit; the data line is further configured to transmit a temperature compensation signal to the pixel driving circuit;

[0014] The temperature compensation signal is determined according to the temperature of the sub-pixel and the data signal.

[0015] Optionally, the first transistor remains turned off throughout the driving process of the sub-pixel.

[0016] Optionally, the first transistor is a P-I-N type transistor.

[0017] Optionally, the display panel further includes: a data line, a first scan line, a second scan line, an initialization signal line, a first power supply line, a second power supply line, a light-emitting control signal line, a detection control signal line, and a detection signal line;

[0018] The pixel driving circuit includes: a driving transistor, a second transistor, a third transistor, a fourth transistor, a fifth transistor, and a sixth transistor;

[0019] The first pole of the second transistor is electrically connected to the first power supply line, the second pole of the second transistor is electrically connected to the first pole of the driving transistor, and the gate of the second transistor is electrically connected to the light emission control signal line; the first pole of the third transistor is electrically connected to the second pole of the driving transistor, the second pole of the third transistor is electrically connected to the first pole of the light emitting device, and the gate of the third transistor is electrically connected to the light emission control signal line; the second pole of the light emitting device is electrically connected to the second power supply line; the gate of the fourth transistor is electrically connected to the first scan line, the first pole of the fourth transistor is electrically connected to the initialization signal line, and the second pole of the fourth transistor is electrically connected to the gate of the driving transistor; the gate of the fifth transistor is electrically connected to the second scan line, the first pole of the fifth transistor is electrically connected to the data line, and the second pole of the fifth transistor is electrically connected to the first pole of the driving transistor; the gate of the sixth transistor is electrically connected to the second scan line, the first pole of the sixth transistor is electrically connected to the second pole of the driving transistor, and the second pole of the sixth transistor is electrically connected to the gate of the driving transistor; the first pole of the first transistor is electrically connected to the first pole of the light emitting device, the gate of the first transistor is electrically connected to the detection control signal line, and the second pole of the first transistor is electrically connected to the detection signal line;

[0020] The first transistors, the second transistor, and the third transistor have the same polarity;

[0021] Preferably, the light emission control signal line is multiplexed as the detection control signal line.

[0022] Accordingly, an embodiment of the present invention further provides a method for detecting the temperature of a display panel, which is used to detect the temperature of the display panel provided in any embodiment of the present invention; the method for detecting the temperature of the display panel includes:

[0023] The temperature detection module detects the temperature of the sub-pixels in the display panel; wherein, the temperature detection module includes a first transistor, and the off-state current of the first transistor represents the temperature of the sub-pixel.

[0024] Accordingly, an embodiment of the present invention further provides a display device, including: a processor and a display panel provided in any embodiment of the present invention; the processor is electrically connected to the first transistor.

[0025] In the display panel provided by the embodiment of the present invention, a temperature detection module composed of a first transistor is arranged in a sub-pixel, and by utilizing the sensitivity of the off-state current of the first transistor to temperature, the temperature of the sub-pixel is characterized by collecting the off-state current of the first transistor. With such an arrangement, firstly, the first transistor can be arranged on the same layer as the transistors in the pixel driving circuit and fabricated in the same process, without increasing the thickness of the display panel or requiring additional fabrication process steps for the display panel. Secondly, during the temperature detection process, the first transistor remains off, and it is possible to detect the temperature of the sub-pixel without the pixel driving circuit providing a detection current to the first transistor according to a preset driving signal; this makes the temperature detection process relatively independent, not relying on the pixel driving circuit to implement, and not affecting the signal transmission inside the pixel driving circuit. Then, the temperature detection process can be carried out at any time during the non-light-emitting stage of the pixel driving circuit, without the need to additionally set up a temperature detection stage. In summary, compared with the prior art, the embodiment of the present invention can detect the temperature of the sub-pixel and provide temperature parameters for the temperature compensation of the sub-pixel without additionally increasing the film layer structure and without changing the sub-pixel driving mode.

[0026] It should be understood that the content described in this part is not intended to identify the key or important features of the embodiments of the present invention, nor is it used to limit the scope of the present invention. Other features of the present invention will become easily understandable through the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following will briefly introduce the drawings required for the description of the embodiments. Obviously, the drawings in the following description are only some embodiments of the present invention, and for those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0028] Figure 1 is a schematic structural diagram of a display panel provided by an embodiment of the present invention;

[0029] Figure 2 is a schematic diagram of the characteristics of a P-type transistor provided by an embodiment of the present invention;

[0030] Figure 3 is a schematic diagram of the characteristics of another P-type transistor provided by an embodiment of the present invention;

[0031] Figure 4 is a schematic structural diagram of a sub-pixel provided by an embodiment of the present invention;

[0032] Figure 5 is a schematic diagram of the driving timing of a sub-pixel provided by an embodiment of the present invention;

[0033] Figure 6It is a schematic diagram of the driving timing of another sub-pixel provided by an embodiment of the present invention;

[0034] Figure 7 It is a schematic diagram of the structure of another sub-pixel provided by an embodiment of the present invention;

[0035] Figure 8 It is a schematic diagram of the driving timing of yet another sub-pixel provided by an embodiment of the present invention;

[0036] Figure 9 It is a schematic diagram of the driving timing of yet another sub-pixel provided by an embodiment of the present invention;

[0037] Figure 10 It is a schematic diagram of the characteristics of an N-type transistor provided by an embodiment of the present invention;

[0038] Figure 11 It is a schematic diagram of the characteristics of another N-type transistor provided by an embodiment of the present invention;

[0039] Figure 12 It is a schematic diagram of the characteristics of a P-I-N type transistor provided by an embodiment of the present invention;

[0040] Figure 13 It is a schematic diagram of the characteristics of another P-I-N type transistor provided by an embodiment of the present invention;

[0041] Figure 14 It is a schematic diagram of the structure of a first transistor provided by an embodiment of the present invention;

[0042] Figure 15 It is a schematic diagram of the manufacturing process of a first transistor provided by an embodiment of the present invention;

[0043] Figure 16 It is a schematic diagram of the structure of a display device provided by an embodiment of the present invention. Detailed implementation manners

[0044] In order to enable those skilled in the art to better understand the solution of the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0045] It should be noted that in the description, claims and the above drawings of the present invention, the terms "first", "second", etc. are used to distinguish similar objects, and do not necessarily describe a specific order or sequence. It should be understood that the data used in this way can be interchanged under appropriate circumstances, so that the embodiments of the present invention described here can be implemented in an order other than those illustrated or described here. In addition, the terms "comprising" and "having" and any variations thereof are intended to cover non-exclusive inclusion.

[0046] An embodiment of the present invention provides a display panel, which may be a self-luminous device display panel such as an organic light-emitting diode display panel, for example, an active organic light-emitting diode display panel. Figure 1 It is a schematic structural diagram of a display panel provided by an embodiment of the present invention. Refer to Figure 1 , the display panel 200 includes: a plurality of sub-pixels 100 arranged in an array. The specific structures of the respective sub-pixels 100 may be the same, Figure 1 The structure of the sub-pixel 100 in the first row and the first column is given as an example. The sub-pixel 100 includes: a pixel driving circuit 110, a light-emitting device OLED, and a temperature detection module 120.

[0047] Among them, the output end of the pixel driving circuit 110 is connected to the light-emitting device OLED, and the pixel driving circuit 110 is used to drive the light-emitting device OLED to emit light. The temperature detection module 120 is used to detect the temperature of the sub-pixel 100. The temperature detection module 120 includes a first transistor M1; the first transistor M1 is connected to the output end of the pixel driving circuit 110, and the off-state current of the first transistor M1 represents the temperature of the sub-pixel 100.

[0048] Taking the first transistor M1 as a P-type transistor as an example, Figure 2 and Figure 3 give the relationship curves between the gate-source voltage difference Vgs, the drive current Ids, and the temperature T of the P-type transistor. Refer to Figure 2 and Figure 3 , taking the drive current Ids equal to 10 -7 A as the critical current value between the on-state and off-state of the transistor; when the drive current Ids is greater than 10 -7 A, it can be considered that the transistor is in the on-state, and the drive current in this case is called the on-state current; when the drive current Ids is less than 10 -7 A, it can be considered that the transistor is in the off-state, and the drive current in this case is called the off current. According to Figure 2 and Figure 3It can be seen that the on-state current of the P-type transistor does not change significantly with temperature, while the off-state current of the P-type transistor has a significant dependence on temperature T. Specifically, the higher the temperature T, the greater the off-state current of the transistor. At the same time, the off-state current of the P-type transistor is also somewhat sensitive to the gate-source voltage difference Vgs. The off-state current of the P-type transistor first decreases and then increases with the increase of the gate-source voltage difference Vgs, and when the gate-source voltage difference Vgs of the P-type transistor is greater than 0V, the trend of the off-state current of the P-type transistor following the change of the gate-source voltage difference Vgs tends to be flat. Generally speaking, when the gate-source voltage Vgs is constant, the off-state current of the transistor increases with the increase of temperature. Therefore, when a certain gate-source voltage difference Vgs is applied to the first transistor M1 to make the first transistor M1 in the off state, the current temperature of the sub-pixel 100 can be obtained by collecting the off-state current of the first transistor M1. Exemplarily, the gate-source voltage difference Vgs can be set to a value greater than 0V (such as 7V) to avoid the large fluctuation of the gate-source voltage difference Vgs from significantly affecting the off-state current, thereby ensuring the accuracy of temperature detection.

[0049] Exemplarily, the driving process of the sub-pixel 100 may include a non-emitting stage and an emitting stage. Since the first transistor M1 is not turned on during the temperature detection process, the temperature detection process will not affect the original signal transmission process in the pixel driving circuit 110. Therefore, the temperature detection process can be carried out at any time period during the non-emitting stage to compensate the emission brightness of the light-emitting device OLED according to the detected temperature during the emitting stage. In this way, it not only does not affect the original driving process of the pixel driving circuit 110, but also can effectively compensate the emission brightness of the light-emitting device OLED. Specifically, the characteristic curve or characteristic table of the first transistor M1 at each gate-source voltage difference and each temperature can be pre-stored in the processor of the display device. The temperature detection process is carried out during the non-emitting stage of the sub-pixel 100. During the temperature detection process, the off-state current of the first transistor M1 is transmitted to the processor. The processor obtains and stores the current temperature of the sub-pixel 100 by looking up the curve or the table, and then determines the temperature compensation parameter of the sub-pixel 100 according to the current temperature. The temperature compensation process can be carried out during the emitting stage by directly applying a compensation current to the light-emitting device OLED; it can also be carried out during the non-emitting stage by providing a temperature compensation signal to the driving transistor in the pixel driving circuit 110 to change the driving current generated by the pixel driving circuit 110 during the emitting stage. The specific compensation method can be set according to the actual situation and is not limited here.

[0050] In the display panel 200 provided by the embodiment of the present invention, a temperature detection module 120 composed of a first transistor M1 is arranged in the sub-pixel 100, and by utilizing the sensitivity of the off-state current of the first transistor M1 to temperature, the temperature of the sub-pixel 100 is characterized by collecting the off-state current of the first transistor M1. With such an arrangement, firstly, the first transistor M1 can be arranged on the same layer as the transistors in the pixel driving circuit 110 and fabricated in the same process, neither increasing the thickness of the display panel 200 nor requiring additional fabrication process steps for the display panel 200. Secondly, during the temperature detection process, the first transistor M1 remains off, and it is not necessary for the pixel driving circuit 110 to provide a detection current to the first transistor M1 according to a preset driving signal to achieve the temperature detection of the sub-pixel 100; this makes the temperature detection process relatively independent, not relying on the pixel driving circuit 110 to implement, and not affecting the signal transmission inside the pixel driving circuit 110. Then, the temperature detection process can be carried out at any time during the non-emitting stage of the pixel driving circuit 110 without the need to additionally set up a temperature detection stage. In summary, compared with the prior art, the embodiment of the present invention can detect the temperature of the sub-pixel 100 without additionally increasing the film layer structure and without changing the sub-pixel driving mode, providing a temperature parameter for the temperature compensation of the sub-pixel 100.

[0051] Continue to refer to Figure 1 , on the basis of the above embodiments, optionally, a detection control signal line Ltest and a detection signal line Lmon are further arranged in the display panel 200 to control the on / off state of the first transistor M1 and provide a transmission path for the off-state current of the first transistor M1. Exemplarily, the detection control signal line Ltest extends along the row direction of the sub-pixel 100, and one detection control signal line Ltest is connected to one row of sub-pixels 100; the detection signal line Lmon extends along the column direction of the sub-pixel 100, and one detection signal line Lmon is connected to one column of sub-pixels 100. Specifically, the detection control signal line Ltest is electrically connected to the gate of the first transistor M1 and is used to transmit a detection control signal to control the on / off state of the first transistor M1. The first pole of the first transistor M1 is connected to the light-emitting device OLED, and the second pole is connected to the detection signal line Lmon. The detection signal line Lmon is used to transmit the off-state current of the first transistor M1 during the temperature detection process. In this display panel 200, a temperature detection module 120 is arranged in each sub-pixel 100, which can achieve pixel-level real-time temperature detection and compensation for the display panel 200, ensure the temperature compensation accuracy, improve the display effect of the display panel 200 at different temperatures, and extend the service life of the devices in the sub-pixel 100.

[0052] In addition, the display panel 200 is also provided with: a first power supply line Lvdd, a second power supply line Lvss, a scan line Lscan, and a data line Ld, so that the pixel driving circuit 110 drives the light-emitting device OLED to emit light and display an image. Exemplarily, the data line Ld extends along the column direction of the sub-pixel 100, and the first power supply line Lvdd, the second power supply line Lvss, and the scan line Lscan all extend along the row direction of the sub-pixel 100; alternatively, the first power supply line Lvdd and the second power supply line Lvss may also extend along the column direction of the sub-pixel 100. Specifically, the pixel driving circuit 110 is electrically connected to the first power supply line Lvdd, the data line Ld, and the scan line Lscan, and the light-emitting device OLED is electrically connected to the second power supply line Lvss.

[0053] Based on the above embodiments, optionally, the pixel driving circuit 110 may be set to any pixel driving circuit structure in the prior art. After detecting the temperature of the sub-pixel 100, the following two methods may be adopted for temperature compensation of the sub-pixel 100: directly transmitting a compensation current to the light-emitting device OLED through the first transistor M1, and the compensation current and the driving current provided by the pixel driving circuit 110 jointly drive the light-emitting device OLED to emit light. Or, transmitting a temperature compensation signal to the pixel driving circuit 110 through the data line Ld, and the temperature compensation signal and the original driving signal (initial data signal) jointly determine the driving current generated by the pixel driving circuit 110 during the light-emitting stage.

[0054] Next, the driving process of the sub-pixel 100 will be specifically described in conjunction with the specific structure of the pixel driving circuit 110.

[0055] Figure 4 is a schematic structural diagram of a sub-pixel provided by an embodiment of the present invention. Refer to Figure 4, in one embodiment, optionally, the pixel driving circuit 110 includes: a driving transistor DTFT, a switching transistor T1, and a storage capacitor Cst, forming a 2T1C pixel circuit structure. Specifically, the gate of the switching transistor T1 is electrically connected to the scan line to receive the scan signal SCAN; the first pole of the switching transistor T1 is electrically connected to the data line to receive the data signal VDATA; the second pole of the switching transistor T1 is electrically connected to the gate of the driving transistor DTFT; the first pole of the driving transistor DTFT is electrically connected to the first power supply line to receive the first power supply signal VDD; the second pole of the driving transistor DTFT serves as the output terminal of the pixel driving circuit 110 and is electrically connected to the first pole of the light-emitting device OLED; the second pole of the light-emitting device OLED is electrically connected to the second power supply line to receive the second power supply signal VSS; one end of the storage capacitor Cst is connected to the first power supply signal VDD, and the other end is electrically connected to the gate of the driving transistor DTFT. The gate of the first transistor M1 is electrically connected to the detection control signal line to receive the detection control signal TEST; the first pole of the first transistor M1 is electrically connected to the first pole of the light-emitting device OLED, and the second pole of the first transistor M1 is electrically connected to the detection signal line Lmon.

[0056] Figure 5 is a schematic diagram of the driving timing of a sub-pixel provided by an embodiment of the present invention. Combining Figure 4 and Figure 5 , taking each transistor as a P-type transistor as an example, the driving process of the sub-pixel 100 includes:

[0057] During the non-light-emitting stage T10, the scan signal SCAN is at a high level, controlling the switching transistor T1 to turn off; the gate of the driving transistor DTFT does not receive the data signal VDATA, and the driving transistor DTFT also turns off, without generating a driving current, and the light-emitting device OLED does not emit light. This stage can be used as a temperature detection stage. During this stage, the detection control signal TEST is at a high level, controlling the first transistor M1 to turn off, and the off-state current Ioff of the first transistor M1 is transmitted to the processor through the detection data line Lmon, and the processor determines the temperature compensation parameter of the sub-pixel 100 according to the off-state current Ioff.

[0058] During the light-emitting stage T20, when the scan signal SCAN is at a low level, the data signal VDATA is the initial data signal V1. At this time, the switching transistor T1 is turned on, and the initial data signal V1 is transmitted to the gate of the driving transistor DTFT. The driving transistor DTFT generates a driving current under the control of the initial data signal V1 and the first power supply signal VDD, driving the light-emitting device OLED to emit light. Then the scan signal SCAN changes to a high level, and the switching transistor T1 is turned off. The storage capacitor Cst maintains the potential of the gate of the driving transistor DTFT at the initial data signal V1, and the driving transistor DTFT continuously generates a driving current. This stage can be used as a temperature compensation stage. In this stage, the detection control signal TEST is at a low level, controlling the first transistor M1 to be turned on. The temperature compensation parameter calculated by the processor in the previous stage is the compensation current Item. During the entire light-emitting stage T20, the current Imon transmitted on the detection signal line Lmon is the compensation current Item. The compensation current Item is transmitted through the first transistor M1 to the light-emitting device OLED, and together with the driving current, drives the light-emitting device OLED to emit light.

[0059] Exemplarily, the compensation current Item is related to the temperature T of the sub-pixel 100 and the data signal VDATA (specifically, the initial data signal V1 input to the pixel driving circuit 110), that is, Item = f(T, V1). Among them, the initial data signal V1 indicates the target brightness of the light-emitting device OLED at a preset temperature. According to the temperature T of the sub-pixel 100, the deviation between the current temperature and the preset temperature of the sub-pixel 100 can be calculated. The compensation current Item calculated according to the above conditions is used to compensate the light-emitting brightness of the light-emitting device OLED, so that the light-emitting device OLED emits light to reach the target brightness at the current temperature.

[0060] This embodiment provides a specific driving method for directly transmitting the compensation current Item to the light-emitting device OLED through the first transistor M1. In this embodiment, the first transistor M1 is turned off during the non-light-emitting stage T10 of the sub-pixel 100 and is turned on during the light-emitting stage T20 of the sub-pixel 100. The temperature detection module 120 participates in both the temperature detection process and the temperature compensation process.

[0061] Figure 6 It is another driving timing diagram of the sub-pixel provided by the embodiment of the present invention. Combining Figure 4 and Figure 6 , in another embodiment, optionally, the driving process of the sub-pixel 100 includes:

[0062] During the non-light-emitting stage T10, the driving process of this stage is the same as that of the non-light-emitting stage in Figure 5 , and will not be described in detail here.

[0063] During the light-emitting stage T20, the detection control signal TEST remains at a high level, the first transistor M1 remains off and does not participate in the temperature compensation process. The temperature compensation parameter calculated by the processor in the previous stage is the temperature compensation signal Vtem. When the scan signal SCAN is at a low level, the data signal VDATA is the sum of the initial data signal V1 and the temperature compensation signal Vtem. At this time, the switching transistor T1 is turned on, and the compensated data signal V1 + Vtem is transmitted to the gate of the driving transistor DTFT. The compensated data signal V1 + Vtem carries temperature compensation information. Therefore, the driving current generated by the driving transistor DTFT includes a temperature compensation current, which can drive the light-emitting device OLED to emit light at the target brightness. After the scan signal SCAN is converted to a high level, the switching transistor T1 is turned off, and the storage capacitor Cst maintains the gate potential of the driving transistor DTFT at V1 + Vtem, and the driving transistor DTFT continuously generates a driving current. Among them, the temperature compensation signal Vtem is also related to the temperature T of the sub-pixel 100 and the initial data signal V1.

[0064] This embodiment provides a specific driving method for transmitting the temperature compensation signal Vtem to the pixel driving circuit 110 through the data line Ld. In this embodiment, the first transistor M1 always remains off during the driving process of the sub-pixel 100, and the temperature detection module 120 only participates in the temperature detection process and does not participate in the temperature compensation process.

[0065] The above embodiments exemplarily show the structure of the 2T1C pixel driving circuit 110, but do not limit the present invention. In other embodiments, the pixel driving circuit can also be set to other structures, which will be specifically described below.

[0066] In one embodiment, optionally, the scan signal lines include: a first scan line for transmitting a first scan signal; a second scan line for transmitting a second scan signal. The display panel is also provided with: a light-emitting control signal line extending along the row direction of the sub-pixel 100 for providing a light-emitting control signal to the pixel driving circuit 110; an initialization signal line extending along the row direction or the column direction of the sub-pixel 100 for providing an initialization signal to the pixel driving circuit 110.

[0067] Figure 7 This is another schematic structural diagram of a sub-pixel provided by an embodiment of the present invention. Refer to Figure 7 In one embodiment, optionally, the pixel driving circuit 110 includes: a driving transistor DTFT, a storage capacitor Cst, a second transistor M2, a third transistor M3, a fourth transistor M4, a fifth transistor M5, a sixth transistor M6, and a seventh transistor M7.

[0068] Among them, the first pole of the second transistor M2 is connected to the first power supply signal VDD, the second pole of the second transistor M2 is electrically connected to the first pole of the driving transistor DTFT, and the gate of the second transistor M2 is connected to the light emission control signal EM; the first pole of the third transistor M3 is connected to the second pole of the driving transistor DTFT, the second pole of the third transistor M3 is connected to the first pole of the light emitting device OLED, and the gate of the third transistor M3 is connected to the light emission control signal EM; the second pole of the light emitting device OLED is connected to the second power supply signal VSS; the gate of the fourth transistor M4 is connected to the first scan signal SCAN1, the first pole of the fourth transistor M4 is connected to the initialization signal Vref, and the second pole of the fourth transistor M4 is electrically connected to the gate of the driving transistor DTFT; the gate of the fifth transistor M5 is connected to the second scan line SCAN2, the first pole of the fifth transistor M5 is connected to the data signal VDATA, and the second pole of the fifth transistor M5 is electrically connected to the first pole of the driving transistor DTFT; the gate of the sixth transistor M6 is connected to the second scan line SCAN2, the first pole of the sixth transistor M6 is connected to the second pole of the driving transistor DTFT, and the second pole of the sixth transistor M6 is connected to the gate of the driving transistor DTFT; the gate of the seventh transistor M7 is connected to the first scan signal SCAN1 or the second scan signal SCAN2, the first pole of the seventh transistor M7 is connected to the initialization signal Vref, and the second pole of the seventh transistor M7 is connected to the first pole of the light emitting device OLED; one end of the storage capacitor Cst is connected to the first power supply signal VDD, and the other end is electrically connected to the gate of the driving transistor DTFT.

[0069] Figure 8 is another driving timing diagram of a sub-pixel provided by an embodiment of the present invention. Combining Figure 7 and Figure 8 , the driving process of the sub-pixel 100 includes: a non-light-emitting stage T10 and a light-emitting stage T20. Among them, the non-light-emitting stage T10 can be further divided into an initialization stage T11 and a data writing stage T12. Here, taking the gate of the seventh transistor M7 being connected to the first scan signal SCAN1 and each transistor in the sub-pixel 100 being a P-type transistor as an example, the driving process of the sub-pixel 100 will be described.

[0070] See Figure 7 and Figure 8 , the driving process of the sub-pixel 100 includes:

[0071] During the initialization stage T11, the emission control signal EM and the second scan signal SCAN2 are at high level, and the first scan signal SCAN1 is at low level. The fourth transistor M4 and the seventh transistor M7 are turned on. The initialization signal Vref is transmitted through the fourth transistor M4 to the gate of the driving transistor DTFT to initialize the gate of the driving transistor DTFT. Meanwhile, the initialization signal Vref is transmitted through the seventh transistor M7 to the first electrode of the light-emitting device OLED to initialize the first electrode of the light-emitting device OLED.

[0072] During the data writing stage T12, the emission control signal EM and the first scan signal SCAN1 are at high level, and the second scan signal SCAN2 is at low level. The fifth transistor M5, the sixth transistor M6 and the driving transistor DTFT are turned on. The data signal VDATA charges the gate of the driving transistor DTFT through the fifth transistor M5, the first and second electrodes of the driving transistor DTFT, and the sixth transistor M6 until the voltage difference between the gate and the first electrode of the driving transistor DTFT is the threshold voltage Vth, completing the data writing of the driving transistor DTFT.

[0073] During the light-emitting stage T20, the emission control signal EM is at low level; both the first scan signal SCAN1 and the second scan signal SCAN2 are at high level. The second transistor M2, the third transistor M3 and the driving transistor DTFT are turned on. The driving transistor DTFT generates a driving current according to its gate voltage to drive the light-emitting device OLED to emit light. Among them, the storage capacitor Cst is used to store the potential of the gate of the driving transistor DTFT to ensure the stability of the gate voltage of the driving transistor DTFT during the light-emitting stage T20, thereby ensuring the stability of the driving current.

[0074] Among them, the non-light-emitting stage T10 is used as the temperature detection stage, and the light-emitting stage T20 is used as the temperature compensation stage.

[0075] Specifically, during the temperature detection stage, the detection control signal TEST is at high level, controlling the first transistor M1 to turn off. The off-state current of the first transistor M1 is transmitted through the detection data line Lmon to the processor. The processor calculates the temperature of the sub-pixel 100 according to the off-state current and calculates the compensation current according to the temperature of the sub-pixel 100 and the data signal.

[0076] During the temperature compensation stage, the detection control signal TEST is at low level, controlling the first transistor M1 to turn on. The compensation current provided by the processor is transmitted through the first transistor M1 to the first electrode of the light-emitting device OLED, and together with the driving current generated by the pixel driving circuit 110, drives the light-emitting device OLED to emit light.

[0077] This embodiment provides another specific driving method for directly transmitting the compensation current to the light-emitting device OLED through the first transistor M1.

[0078] Based on the above embodiments, optionally, the first transistor M1, the second transistor M2, and the third transistor M3 have the same polarity. In this way, transistors in the pixel driving circuit 110 and the temperature detection module 120 can be fabricated using exactly the same process, simplifying the manufacturing process of the display panel. At the same time, according to Figure 8 As can be seen, when the first transistor M1, the second transistor M2, and the third transistor M3 have the same polarity, the waveforms of the light emission control signal EM and the detection control signal TEST are the same. Therefore, the light emission control signal line can be reused as the detection control signal line, thereby reducing the number of signal lines in the display panel and simplifying the structure and wiring of the display panel.

[0079] Figure 9 FIG. is a schematic diagram of another driving timing of a sub-pixel provided by an embodiment of the present invention. Refer to Figure 9 , Figure 9 The driving timing of the pixel driving circuit 110 in Figure 8 is the same as that in

[0080] Refer to Figure 9 and Figure 7 . In this embodiment, the initialization stage T11 serves as the temperature detection stage, and the data writing stage T12 serves as the temperature compensation stage.

[0081] Specifically, in the temperature detection stage, the detection control signal TEST is at a high level, controlling the first transistor M1 to turn off. The off-state current of the first transistor M1 is transmitted to the processor through the detection data line Lmon. The processor calculates the temperature of the sub-pixel 100 based on this off-state current, and calculates the temperature compensation signal according to the temperature of the sub-pixel 100 and the data signal.

[0082] In the temperature compensation stage, the detection control signal TEST remains at a high level, and the first transistor M1 remains off and does not participate in the temperature compensation process. The temperature compensation signal provided by the processor is transmitted to the fifth transistor M5 through the data line, and then transmitted to the gate of the driving transistor DTFT via the fifth transistor M5, the first and second poles of the driving transistor DTFT, and the sixth transistor M6. The temperature compensation signal and the data signal jointly determine the driving current generated by the driving transistor DTFT in the light emission stage T20.

[0083] This embodiment provides another specific driving method for transmitting the temperature compensation signal to the pixel driving circuit 110 through the data line.

[0084] It should be noted that the above embodiments exemplarily give the temperature detection and compensation methods when the first transistor M1 is a P-type transistor, but do not limit the present invention. In other embodiments, the first transistor M1 can also be set to other types, and several setting methods will be described below.

[0085] In one embodiment, optionally, the first transistor M1 is an N-type transistor. Figure 10 It is a schematic diagram of the characteristics of an N-type transistor provided by an embodiment of the present invention; Figure 11 It is a schematic diagram of the characteristics of another N-type transistor provided by an embodiment of the present invention. Refer to Figure 10 and Figure 11 , the relationship between the gate-source voltage difference Vgs, the drive current Ids, and the temperature T of the N-type transistor is as follows: Still taking the drive current Ids equal to 10 -7 A as the critical current value between the on-state and off-state of the transistor for example. The off-state current of the N-type transistor has a significant dependence on the temperature T, specifically manifested as: the higher the temperature T, the greater the off-state current of the transistor. At the same time, the off-state current of the N-type transistor also has a certain sensitivity to its gate-source voltage difference Vgs. The off-state current of the N-type transistor first decreases and then increases with the increase of the gate-source voltage difference Vgs, and when the gate-source voltage difference Vgs of the N-type transistor is less than 3V, the trend of the off-state current of the N-type transistor following the change of the gate-source voltage difference Vgs tends to be flat. Generally speaking, when the gate-source voltage Vgs is constant, the off-state current of the transistor increases with the increase of the temperature. Therefore, when the first transistor M1 is an N-type transistor, its off-state current can effectively characterize the temperature of the sub-pixel. Exemplarily, the gate-source voltage difference Vgs can be set to a value less than 3V to reduce the influence of the fluctuation of the gate-source voltage difference Vgs on the off-state current, thereby ensuring the accuracy of temperature detection. Preferably, when an N-type transistor is used in the pixel drive current 110, the first transistor M1 can be set to be an N-type transistor as well to simplify the manufacturing process of the display panel.

[0086] In another embodiment, optionally, the first transistor M1 is a P-I-N type transistor. Figure 12 It is a schematic diagram of the characteristics of a P-I-N type transistor provided by an embodiment of the present invention; Figure 13 It is a schematic diagram of the characteristics of another P-I-N type transistor provided by an embodiment of the present invention. Refer to Figure 12 and 13, the characteristic differences between P-I-N transistors and P-type or N-type transistors are mainly reflected in that: the P-I-N transistor is in the off state when the gate-source voltage difference Vgs is in the range of -5 to 10V, and the off-state current of the P-I-N transistor is not sensitive to the change of the gate-source voltage difference Vgs. Therefore, compared with using N-type transistors and P-type transistors as temperature detection devices, the off-state current of the P-I-N transistor changes less with the voltage change of the gate-source voltage difference Vgs, has a larger working range, more accurate temperature detection, and high working stability.

[0087] It should be noted that control signals for controlling the switching states of the respective switching transistors in the driving pixel circuit 110, such as the emission control signal EM and the high and low levels of the respective scanning signals, cannot control the P-I-N transistor to conduct. Therefore, when using Figure 9 the timing-driven sub-pixel 100 shown, the emission control signal EM, the first scanning signal SCAN1, or the second scanning signal SCAN2 can be multiplexed as the detection control signal TEST, which can simplify the structure of the display panel on the basis of ensuring that the first transistor M1 is always turned off during the driving process of the sub-pixel 100.

[0088] Figure 14 is a schematic structural diagram of a first transistor provided by an embodiment of the present invention. Refer to Figure 14 , on the basis of the above embodiments, optionally, the first transistor includes: a substrate layer 310, a buffer layer 320, an active layer 330, a first insulating layer 340, a gate 350, a second insulating layer 360, and an electrode layer (including a first pole 371 and a second pole 372) stacked from bottom to top. Among them, the active layer 330 includes a first source-drain region 331, a channel region 332, and a second source-drain region 333; the first pole 371 is in contact with the first source-drain region 331 through a via, and the second pole 372 is in contact with the second source-drain region 333 through a via. Since the first transistor is a symmetric structure, the present invention does not distinguish between the source region and the drain region of the first transistor, and collectively refers to them as the source-drain region. Exemplarily, the first source-drain region 331 can be used as the source region, and the second source-drain region 333 can be used as the drain region. Correspondingly, the first pole 371 can be used as the source electrode, and the second pole 372 can be used as the drain electrode.

[0089] Among them, the difference between the P-type or N-type transistor and the P-I-N transistor mainly lies in the structure of the active layer 330. Whether it is a P-type transistor or an N-type transistor, the doping types of its first source-drain region 331 and second source-drain region 333 are the same and can be fabricated in the same process. For the P-I-N transistor, the doping types of its first source-drain region 331 and second source-drain region 333 are different and need to be ion-implanted separately.

[0090] Figure 15It is a schematic diagram of the manufacturing process of a first transistor provided by an embodiment of the present invention. Refer to Figure 15 , in one embodiment, optionally, the manufacturing steps of the P-I-N type first transistor include:

[0091] S10. Provide a stacked substrate layer 310, a buffer layer 320, and an active layer 330.

[0092] Among them, the specific manufacturing process of the active layer can be: depositing an amorphous silicon (a-Si) layer on the buffer layer 320, and after the a-Si layer is subjected to an excimer laser annealing (ELA) process, it is converted into polycrystalline silicon (Poly-Si) to form an intrinsic type active layer 330.

[0093] S20. Perform B ion implantation on the second source / drain region 333 to form the P end of the transistor.

[0094] S30. Perform P ion implantation on the first source / drain region 331 to form the N end of the transistor.

[0095] S40. Sequentially fabricate a first insulating layer 340, a gate 350, a second insulating layer 360, a first electrode 371, and a second electrode 372 on the active layer 330 to form a P-I-N type first transistor.

[0096] The embodiment of the present invention also provides a display device, which can be, for example, any product or component with a display function such as a mobile phone, a tablet computer, a television, or a monitor. The display device includes a display panel provided by any embodiment of the present invention and has corresponding beneficial effects. Figure 16 It is a schematic diagram of the structure of a display device provided by an embodiment of the present invention. Refer to Figure 16 , the display device 10 includes: a processor 300 and a display panel 200; the processor 300 is electrically connected to each first transistor M1, specifically electrically connected to each first transistor M1 through a detection signal line Lmon.

[0097] Exemplarily, the processor 300 can be as Figure 16 shown, connected to both the detection signal line Lmon and each data line Ld. While realizing the temperature detection function, the processor 300 also serves as a driving module for providing data signals to each sub-pixel 100. Alternatively, the processor 300 and the driving chip can be separately provided, the driving chip is connected to each data line Ld; the processor 300 is connected to each detection signal line Lmon and is connected to the driving chip. The specific setting method can be selected according to actual needs.

[0098] The embodiment of the present invention also provides a method for detecting the temperature of a display panel, which is used to detect the temperature of the display panel provided by any embodiment of the present invention and has corresponding beneficial effects. The method for detecting the temperature of the display panel includes:

[0099] The temperature detection module detects the temperature of the sub-pixels in the display panel; wherein, the temperature detection module includes a first transistor, and the off-state current of the first transistor characterizes the temperature of the sub-pixels.

[0100] In the temperature detection method of the display panel provided by the embodiments of the present invention, by utilizing the sensitivity of the off-state current of the first transistor to temperature, the temperature of the sub-pixels is characterized by collecting the off-state current of the first transistor. In this way, on the one hand, the first transistor can be arranged on the same layer as the transistors in the pixel driving circuit of the sub-pixels and fabricated in the same process, neither increasing the thickness of the display panel nor requiring additional fabrication process steps for the display panel. On the other hand, during the temperature detection process, the first transistor remains off, and the temperature detection of the sub-pixels can be achieved without the pixel driving circuit providing a detection current to the first transistor according to a preset driving signal; this makes the temperature detection process relatively independent, not dependent on the pixel driving circuit to implement, and does not affect the signal transmission inside the pixel driving circuit. Then, the temperature detection process can be carried out at any time during the non-light-emitting stage of the pixel driving circuit without additional temperature detection stages. In summary, compared with the prior art, the embodiments of the present invention can detect the temperature of the sub-pixels without additionally increasing the film layer structure and without changing the sub-pixel driving mode, providing temperature parameters for the temperature compensation of the sub-pixels.

[0101] Based on the above embodiments, optionally, after detecting the temperature of the sub-pixels, the following two methods can be used to perform temperature compensation on the sub-pixels: The first method: During the light-emitting stage, a compensation current is directly applied to the light-emitting device through the first transistor. The second method: During the non-light-emitting stage, a temperature compensation signal is provided to the driving transistor in the pixel driving circuit, so that the temperature compensation signal acts on the driving transistor to change the driving current generated by the driving transistor during the light-emitting stage. Such a setting can achieve the temperature detection and compensation of the sub-pixels without changing the original driving timing of the sub-pixels.

[0102] It should be understood that the various forms of the flow shown above can be used, with steps reordered, added, or deleted. For example, the steps described in the present invention can be executed in parallel, sequentially, or in a different order, as long as the desired results of the technical solution of the present invention can be achieved, and no limitations are imposed herein.

[0103] The above specific embodiments do not constitute a limitation on the protection scope of the present invention. Those skilled in the art should understand that various modifications, combinations, sub-combinations, and substitutions can be made according to design requirements and other factors. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention shall be included within the protection scope of the present invention.

Claims

1. A display panel, characterized in that, Comprising: Sub-pixels; The sub-pixels include: A pixel driving circuit and a light-emitting device; an output terminal of the pixel driving circuit is connected to the light-emitting device, and the pixel driving circuit is configured to drive the light-emitting device to emit light; A temperature detection module for detecting the temperature of the sub-pixels, the temperature detection module including a first transistor; the first transistor is connected to the output terminal of the pixel driving circuit, and the off-state current of the first transistor characterizes the temperature of the sub-pixels; The first transistor is further configured to transmit a compensation current to the light-emitting device.

2. The display panel according to claim 1, wherein Further comprising: A data line; the data line is electrically connected to the pixel driving circuit and is configured to transmit a data signal to the pixel driving circuit; The compensation current is determined according to the temperature of the sub-pixels and the data signal.

3. The display panel according to claim 1, characterized in that, The first transistor is turned off during a non-light-emitting stage of the sub-pixels and is turned on during a light-emitting stage of the sub-pixels.

4. The display panel according to claim 1, characterized in that, The first transistor is a P-I-N type transistor.

5. The display panel according to claim 1, wherein Further comprising: A data line, a first scan line, a second scan line, an initialization signal line, a first power supply line, a second power supply line, a light-emitting control signal line, a detection control signal line, and a detection signal line; The pixel driving circuit includes: a driving transistor, a second transistor, a third transistor, a fourth transistor, a fifth transistor, and a sixth transistor; A first pole of the second transistor is electrically connected to the first power supply line, a second pole of the second transistor is electrically connected to a first pole of the driving transistor, and a gate of the second transistor is electrically connected to the light-emitting control signal line; a first pole of the third transistor is electrically connected to a second pole of the driving transistor, a second pole of the third transistor is electrically connected to a first pole of the light-emitting device, and a gate of the third transistor is electrically connected to the light-emitting control signal line; a second pole of the light-emitting device is electrically connected to the second power supply line; a gate of the fourth transistor is electrically connected to the first scan line, a first pole of the fourth transistor is electrically connected to the initialization signal line, and a second pole of the fourth transistor is electrically connected to a gate of the driving transistor; a gate of the fifth transistor is electrically connected to the second scan line, a first pole of the fifth transistor is electrically connected to the data line, and a second pole of the fifth transistor is electrically connected to a first pole of the driving transistor; a gate of the sixth transistor is electrically connected to the second scan line, a first pole of the sixth transistor is electrically connected to a second pole of the driving transistor, and a second pole of the sixth transistor is electrically connected to a gate of the driving transistor; a first pole of the first transistor is electrically connected to a first pole of the light-emitting device, a gate of the first transistor is electrically connected to the detection control signal line, and a second pole of the first transistor is electrically connected to the detection signal line; The first transistor, the second transistor, and the third transistor have the same polarity.

6. The display panel according to claim 5, characterized in that, The light-emitting control signal line is multiplexed as the detection control signal line.

7. A method for detecting the temperature of a display panel, characterized in that, For temperature detection of the display panel according to any one of claims 1-6; the temperature detection method of the display panel includes: The temperature detection module detects the temperature of the sub-pixels in the display panel; wherein, the temperature detection module includes a first transistor, and the off-state current of the first transistor represents the temperature of the sub-pixel.

8. A display device, characterized in that, Comprising: a processor and a display panel according to any one of claims 1-6; The processor is electrically connected to the first transistor.

Images