Display panel and display device

Abstract

The present invention discloses a display panel and a display device, wherein the display panel includes: a pre-detection photosensitive circuit, a plurality of precise detection photosensitive circuits and a driver chip; the pre-detection photosensitive circuit is used to obtain a first photosensitive current signal of the ambient brightness; the driver chip is connected to the pre-detection photosensitive circuit and is used to send an enable signal to the corresponding precise detection photosensitive circuit according to the first photosensitive current signal, so that the precise detection photosensitive circuit obtains a second photosensitive current signal of the ambient brightness; the driver chip is also used to obtain an ambient brightness measurement value according to the second photosensitive current signal; the step current signal of the pre-detection photosensitive circuit is greater than the step current signal of the precise detection photosensitive circuit. The technical solution provided by the present invention can achieve higher light sensing detection accuracy under low ambient brightness through fewer data gears.

Description

Technical Field

[0001] The present invention relates to the field of display technology, and in particular to a display panel and a display device. Background Art

[0002] In recent years, with the continuous development of display technology, in order to enrich the use functions of display panels, sensors capable of realizing different functions, such as light sensors, are usually integrated in the display panels.

[0003] Mobile phones and other electronic devices have high precision requirements for light sensors. For example, although the light sensing accuracy requirements for light sensors are not high under high ambient brightness, in order to maintain the accuracy of light sensors under low ambient brightness, high light sensing accuracy requirements are required.

[0004] However, the data detection range and accuracy range of the currently commonly used low-cost driver chips are poor, and cannot meet the light sensing accuracy requirements of light sensors under low ambient brightness. Summary of the invention

[0005] Embodiments of the present invention provide a display panel and a display device to achieve higher light sensing detection accuracy under low ambient brightness through fewer data levels.

[0006] In a first aspect, an embodiment of the present invention provides a display panel, including: a pre-detection light sensing circuit, a plurality of precise detection light sensing circuits and a driving chip;

[0007] The pre-detection light sensing circuit is used to obtain a first light sensing current signal of the ambient brightness;

[0008] The driver chip is connected to the pre-detection light sensing circuit, and is used to send an enable signal to the corresponding precise detection light sensing circuit according to the first light sensing current signal, so that the precise detection light sensing circuit obtains a second light sensing current signal of the ambient brightness;

[0009] The driver chip is also used to obtain an ambient brightness measurement value according to the second photosensitive current signal; the step current signal of the pre-detection photosensitive circuit is greater than the step current signal of the precise detection photosensitive circuit.

[0010] In a second aspect, an embodiment of the present invention provides a display device, including the display panel provided by any embodiment of the present invention.

[0011] In the present invention, a pre-detection photosensitive circuit and a plurality of precise detection photosensitive circuits are provided, and a first photosensitive current signal is obtained through a pre-detection photosensitive circuit with a larger step current signal, thereby obtaining a photosensitive current signal with a smaller precision. The driver chip can select a precise detection photosensitive circuit with a smaller current signal and a range covering the first photosensitive current signal through the first photosensitive current signal, and obtain a second photosensitive current signal through the precise detection photosensitive circuit. Because the detection precision of the precise detection photosensitive circuit is higher than that of the pre-detection photosensitive circuit, this embodiment can obtain a precise ambient brightness measurement value through the precise detection photosensitive circuit. The present invention does not need to adjust the number of data gears of the driver chip, and can set photosensitive circuits with different step current signals, so that different photosensitive circuits reuse the data gears of the driver chip, and achieve high-precision detection under low ambient brightness and large-range detection requirements under high ambient brightness. A driver chip with fewer data gears can be used to achieve a higher light sensing detection precision under low ambient brightness, effectively saving the cost of the driver chip. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 A schematic diagram of the structure of a display panel provided by an embodiment of the present invention;

[0013] Figure 2 A schematic diagram of the structure of another display panel provided by an embodiment of the present invention;

[0014] Figure 3 A schematic diagram of the structure of another display panel provided by an embodiment of the present invention;

[0015] Figure 4 A schematic diagram of the structure of a pre-detection light sensing circuit provided by an embodiment of the present invention;

[0016] Figure 5 A schematic diagram of the structure of a precise detection light sensing circuit provided by an embodiment of the present invention;

[0017] Figure 6 for Figure 4 The driving timing diagram of the pre-detection light sensing circuit;

[0018] Figure 7 for Figure 4 Schematic diagram of the state of the pre-detection light sensing circuit in the first stage;

[0019] Figure 8 for Figure 4 Schematic diagram of the state of the pre-detection light sensing circuit in the second stage;

[0020] Fig. 9 for Figure 4 A schematic diagram of another state of the pre-detection light sensing circuit in the second stage;

[0021] Fig.10 for Figure 4 Schematic diagram of the state of the pre-detection light sensing circuit in the third stage;

[0022] Fig.11 A schematic diagram of a first current ratio range where the first node potential is -25 to 5V provided by an embodiment of the present invention;

[0023] Fig.12 A schematic diagram of a first current ratio range in which the first node potential is 5 to 12 V provided by an embodiment of the present invention;

[0024] Fig.13 A schematic diagram of a first current ratio range in which the first node potential is 12 to 25 V provided in an embodiment of the present invention;

[0025] Fig.14 A schematic diagram of a first current ratio range in which the first node potential is 25 to 40 V provided in an embodiment of the present invention;

[0026] Fig.15 A schematic structural diagram of a display device provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0027] The present invention will be further described in detail below in conjunction with the accompanying drawings and embodiments. It is to be understood that the specific embodiments described herein are only used to explain the present invention, rather than to limit the present invention. It should also be noted that, for ease of description, only parts related to the present invention, rather than all structures, are shown in the accompanying drawings.

[0028] Display device end customers have high precision requirements for light sensing of the device's ambient brightness, so as to adjust the brightness of the display panel according to changes in ambient brightness to obtain a more comfortable viewing experience. For example, in low ambient brightness, such as at night, the human eye is more sensitive, and the display panel needs to accurately detect the ambient brightness to obtain the optimal brightness value of the corresponding display panel. In addition, light sensing can also be used for a variety of operations such as fingerprint recognition and touch recognition, thereby improving the accuracy of the corresponding operations and further increasing the demand for light sensing detection accuracy.

[0029] For example, in a low-brightness environment, the brightness accuracy requirement can be 1lux. At the same time, the light sensor's light sensitivity range is required to be 1 to 10,000 lux. At higher brightness, the human eye is insensitive to small brightness changes, such as 1lux. Therefore, in a higher brightness state, the light sensitivity accuracy requirement is reduced to 10lux, 20lux, etc. For driver chips with lower costs and poorer performance, their data detection range and accuracy are poor. For example, ILI9881T, its current detection range is 40uA to 300uA, with an accuracy of 0.05uA. There are a total of 5200 data levels corresponding to 40uA, 40.05uA, 40.1uA, 40.15uA...300uA. These 5200 data levels cannot support 1uA to 10,000lux, and each data level represents a brightness step of 1lux. That is to say, in the brightness range of 1uA to 10,000 lux, the detection accuracy of the detector is 1 lux, which requires 10,000 data levels. The number of data levels required by the detector exceeds the number of data levels that the driver chip can provide, that is, the driver chip with the above performance cannot meet the detection accuracy requirements under low ambient brightness.

[0030] To solve the above problems, an embodiment of the present invention provides a display panel, such as Figure 1 As shown, Figure 1 A schematic diagram of the structure of a display panel provided by an embodiment of the present invention, the display panel comprises: a pre-detection light sensing circuit 11, a plurality of precise detection light sensing circuits 12 and a driving chip 13;

[0031] The pre-detection light sensing circuit 11 is used to obtain a first light sensing current signal of the ambient brightness;

[0032] The driver chip 13 is connected to the pre-detection light sensing circuit 11, and is used to send an enable signal to the corresponding precise detection light sensing circuit 12 according to the first light sensing current signal, so that the precise detection light sensing circuit 12 obtains the second light sensing current signal of the ambient brightness;

[0033] The driving chip 13 is further used to obtain the ambient brightness measurement value according to the second light sensing current signal; the step current signal of the pre-detection light sensing circuit 11 is greater than the step current signal of the precise detection light sensing circuit 12.

[0034] It should be noted that the number of data gears of the driver chip 13 with low cost or poor performance is not enough. When the brightness measurement range is large, the brightness accuracy is small. When the brightness measurement range is small, the brightness accuracy is small, so it is difficult to achieve a large range and high-precision ambient brightness measurement. In this embodiment, the above-mentioned driver chip 13 can detect the ambient brightness by setting a photosensitive circuit with multiple ranges. Specifically, a pre-detection photosensitive circuit 11 is provided in this embodiment. Because the range of the current ambient brightness is uncertain, the range of the photosensitive current signal cannot be effectively locked. In this embodiment, the ambient brightness is first measured by the pre-detection photosensitive circuit 11 with a large measurement range but low measurement accuracy (the ambient brightness is obtained by the first photosensitive current signal in this embodiment). Exemplarily, the measurement accuracy of the pre-detection photosensitive circuit 11 is controlled, that is, the step current signal is 10lux, and the measurement accuracy is the unit change value of the current signal measured by the current photosensitive circuit, that is, the minimum change value. If the driver chip 13 has 5200 data gears, the ambient brightness in the range of 1 to 10000 lux can be effectively obtained because it only needs to occupy 1000 data gears. For example, the pre-detection photosensor circuit 11 can measure a first photosensor current signal, and the driver chip 13 learns that the current ambient brightness is 1230 lux according to the first photosensor current signal.

[0035] The number of precise detection photosensitive circuits 12 can be set to multiple, and the step current signal of the step current signal is smaller than that of the pre-detection photosensitive circuit 11. For example, the brightness value corresponding to the step current signal can be 1lux or 0.5lux, etc., thereby further increasing the accuracy of ambient brightness detection. Figure 1In the figure, four precise detection photosensitive circuits 12 are used as an example for illustration. Multiple precise detection photosensitive circuits 12 may have different ranges, for example, 1 to 2500 lux, 2500 to 5000 lux, 5000 to 7500 lux and 7500 to 10000 lux. The above ranges may not have intersections of data segments, and each range is spliced ​​to form a larger environmental measurement range of 1 to 10000 lux. And if the brightness value corresponding to the step current signal is 1 lux, each precise detection photosensitive circuit 12 only occupies 2500 data positions, so that a general driver chip 13 can achieve high-precision environmental brightness detection. If the current ambient brightness is 1230 lux according to the pre-detection photosensitive circuit 11, it can be known that its range is within 1 to 2500 lux. The ambient brightness is accurately measured again by the photosensitive circuit 12 with accurate detection of the range, and a second photosensitive current signal is output. The measurement accuracy of the second photosensitive current signal is high, so that the driver chip 13 can parse a more accurate ambient brightness measurement value from the second photosensitive current signal. For example, the current ambient brightness measurement value can be obtained as 1236 lux. In this embodiment, a plurality of photosensitive circuits with different ranges are set, and each photosensitive circuit can reuse the data gear of the driver chip 13 respectively, while saving the production cost of the driver chip 13, a large brightness range under low ambient brightness and high-precision brightness detection can be achieved as much as possible. In addition, there can be a certain intersection between the ranges of the above-mentioned precise detection photosensitive circuits 12. For example, the ranges can be 1 to 3000 lux and 2500 to 5000 lux, respectively, and this embodiment does not specifically limit this.

[0036] In the above example, the step current signals of each precise detection photosensitive circuit 12 are the same. In this embodiment, different precise detection photosensitive circuits 12 can be set to have different step current signals. For example, there is a precise detection photosensitive circuit 12 with a step current signal corresponding to a brightness value of 1lux, and another precise detection photosensitive circuit 12 with a step current signal corresponding to a brightness value of 0.1lux. Under low ambient brightness, a suitable precise detection photosensitive circuit 12 can be selected for brightness detection according to the sensitivity of the human eye to the ambient brightness.

[0037] In this embodiment, the pre-detection photosensitive circuit 11 can transmit the first photosensitive current signal to the driver chip 13 through its separate signal line, and the remaining precise detection photosensitive circuits 12 can transmit the second photosensitive current signal to the driver chip 13 through the same signal line, and the driver chip 13 is provided with a separate signal line corresponding to each precise detection photosensitive circuit 12 to transmit an enable signal to control the precise detection photosensitive circuit 12 to measure brightness. And the driver chip 13 can also provide power signals, scanning signals, and drive signals to the pre-detection photosensitive circuit 11 and multiple precise detection photosensitive circuits 12 at the same time through at least one signal line. On this basis, Figure 2 As shown, Figure 2 A structural schematic diagram of another display panel provided in an embodiment of the present invention, in order to further reduce the wiring between the driver chip 13 and each photosensitive circuit, the pre-detection photosensitive circuit 11 and the precise detection photosensitive circuit 12 can input the photosensitive current signal to the driver chip 13 through the same signal line, thereby reducing the wiring and reducing the circuit layout area.

[0038] In the embodiment of the present invention, a pre-detection photosensitive circuit and a plurality of precise detection photosensitive circuits are provided, and a first photosensitive current signal is obtained through a pre-detection photosensitive circuit with a larger step current signal, thereby obtaining a photosensitive current signal with a smaller precision. The driver chip can select a precise detection photosensitive circuit with a smaller current signal and a range covering the first photosensitive current signal through the first photosensitive current signal, and obtain a second photosensitive current signal through the precise detection photosensitive circuit. Because the detection precision of the precise detection photosensitive circuit is higher than that of the pre-detection photosensitive circuit, the present embodiment can obtain a precise ambient brightness measurement value through the precise detection photosensitive circuit. The present invention does not need to adjust the number of data gears of the driver chip, and can set photosensitive circuits with different step current signals, so that different photosensitive circuits reuse the data gears of the driver chip, and achieve high precision under low ambient brightness and large range detection requirements under high ambient brightness, and can use a driver chip with fewer data gears to achieve a higher light sensing detection precision under low ambient brightness, effectively saving the cost of the driver chip.

[0039] The above is the core idea of ​​the present invention. The technical scheme in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0040] Figure 3 A structural schematic diagram of another display panel provided in an embodiment of the present invention, optionally, the pre-detection light sensing circuit 11 may include: a first light sensing measurement module 111 and a first reference signal module 112; the first light sensing measurement module 111 is used to generate a first light sensing current signal according to the ambient brightness; the first reference signal module 112 is used to generate a first reference current signal according to the zero brightness state. In order to further improve the accuracy of the light sensing current signal, so as to accurately lock the ambient brightness range, and facilitate the driver chip 13 to select the correct precise detection light sensing circuit 12, the pre-detection light sensing circuit 11 may be provided with a first reference signal module 112, and the first reference signal module 112 is mainly used to obtain the current signal in the zero brightness state under the measurement accuracy of the current pre-detection light sensing circuit 11 as the first reference current signal, and compare it with the first light sensing current signal, so as to enhance the brightness measurement accuracy.

[0041] Optionally, the driver chip 13 can be specifically used to: obtain the first photosensitive current signal and the first reference current signal; use the ratio of the first photosensitive current signal to the first reference current signal as the first current ratio; obtain the precise detection photosensitive circuit 12 whose measurement range covers the first current ratio, and send an enable signal to it. After the pre-detection photosensitive circuit 11 outputs the first photosensitive current signal and the first reference current signal to the driver chip 13, the driver chip 13 uses the ratio of the first photosensitive current signal to the first reference current signal as the first current ratio. The first current ratio can replace the first photosensitive current signal and become a value that can better measure the ambient brightness, so that the driver chip 13 obtains the range in which the first current ratio is located, thereby sending an enable signal to the precise detection photosensitive circuit 12 with an accurate measurement range, thereby improving the accuracy of ambient brightness measurement.

[0042] And because the signal output by each accurate detection light sensing circuit 12 also includes a light sensing current signal and a reference current signal, the driver chip 12 does not need to convert the first current ratio into a specific brightness value to accurately detect the selection of the light sensing circuit 12, and can directly select the accurate detection light sensing circuit 12 according to the current ratio range of the accurate detection light sensing circuit 12. Figure 3 , the precise detection light sensing circuit 12 may include: a second light sensing measurement module 121, a second reference signal module 122 and an enable module 123; the enable module 123 is used to control the second light sensing measurement module 121 and the second reference signal module 122 to measure the current signal according to the enable signal; the second light sensing measurement module 121 is used to generate a second light sensing current signal according to the ambient brightness; the second reference signal module 122 is used to generate a second reference current signal according to the zero brightness state. Similarly, in order to further improve the accuracy of the light sensing current signal, so as to accurately lock the accuracy of the ambient brightness measurement, and facilitate the driver chip 13 to parse the specific ambient brightness measurement value, the precise detection light sensing circuit 12 is provided with a second reference signal module 122, and the second reference signal module 122 is mainly used to obtain the current signal in the zero brightness state under the measurement accuracy of the current precise detection light sensing circuit 12 as the second reference current signal, and compare it with the second light sensing current signal, so as to enhance the brightness measurement accuracy.

[0043] Optionally, the driver chip 13 can be specifically used to: obtain a second photosensor current signal and a second reference current signal; use the ratio of the second photosensor current signal to the second reference current signal as a second current ratio; obtain an ambient brightness measurement value based on the second current ratio to further enhance the accuracy of ambient brightness measurement.

[0044] Figure 4 A schematic diagram of the structure of a pre-detection photosensor circuit provided in an embodiment of the present invention. Figure 5A schematic diagram of a precise detection photosensitive circuit provided by an embodiment of the present invention. Optionally, the first photosensitive measurement module 111 and the second photosensitive measurement module 121 may include: a first writing module 22, a first photosensitive module 21, a first threshold compensation module 23, a first coupling module 24, a first discharge module 25, and a second photosensitive module 26; the control end of the first writing module 22 is connected to the first scanning signal step1; the first writing module 22 is used to connect the first power supply signal VGH and the first node N1; the first node N1 is respectively connected to the control ends of the first photosensitive module 21 and the second photosensitive module 26; the first threshold compensation module 23 connects the first node N1 to the first end of the first photosensitive module 21 in response to the second scanning signal step2; the first threshold compensation module 24 connects the first node N1 to the first end of the first photosensitive module 21; 3 also connects the second end of the first light sensing module 21 with the second level output end V2 in response to the second scanning signal step2; the first end of the second light sensing module 26 is connected to the first level output end V1; the second end of the second light sensing module 26 is used as the light sensing current signal output end; the first discharge module 25 connects the first end of the first light sensing module 21 with the first power signal VGH in response to the third scanning signal step3; the first discharge module 25 also connects the second end of the first light sensing module 21 with the second power signal VGL in response to the third scanning signal step3; the first end of the first coupling module 24 is connected to the third scanning signal step3; the second end of the first coupling module 24 is connected to the first node N1.

[0045] refer to Figure 4 In this embodiment, both the first light sensing measurement module 111 and the second light sensing measurement module 121 can output light sensing current signals, and both of them include the first light sensing module 21 and the second light sensing module 26. The first light sensing module 21 and the second light sensing module 26 can generate electrons under the influence of the ambient brightness, and the electron transmission generates current, that is, light energy is converted into electrical energy. When the ambient brightness is higher, the output current of the first light sensing module 21 and the second light sensing module 26 is larger. Therefore, in this embodiment, the first light sensing measurement module 111 and the second light sensing measurement module 121 sense the brightness change and generate light sensing current signals. And because the first light sensing current signal output by the first light sensing measurement module 111 and the second light sensing current signal output by the second light sensing measurement module 121 are both related to the voltage value of the first node N1, in this embodiment, the first light sensing measurement module 111 and the second light sensing measurement module 121 can specifically control the first light sensing measurement module 111 and the second light sensing measurement module 121 to have different measurement accuracies by adjusting the node voltage of the first node N1, thereby realizing a large range and high-precision ambient brightness detection under low ambient brightness.

[0046] In the light sensing measurement module, the first writing module 22 can affect the first scanning signal step1 to write the first power signal VGH to the first node N1, and turn on the first light sensing module 21 and the second light sensing module 26 at the same time; the first threshold compensation module 23 can respond to the second scanning signal step2 to write the second level and the threshold voltage of the first light sensing module 21 into the first node N1, so as to prevent the threshold voltage of the first light sensing module 21 from affecting the light sensing current signal; in addition, the first coupling module 24 can respond to the third scanning signal step3 to continue to increase the potential of the first node N1, so that the second light sensing module 26 outputs the light sensing current signal. In order to keep the control terminal voltages of the first light sensing module 21 and the second light sensing module 26 consistent, so that the control terminal voltage of the second light sensing module 26 can be obtained through the first light sensing module 21, when the second light sensing module 26 is turned on, the first light sensing module 21 can also remain turned on, and the first discharge module 25 can provide a discharge circuit for the first light sensing module 21 to be turned on.

[0047] Continue to refer Figure 4 and Figure 5 Optionally, the first reference signal module 112 and the second reference signal module 122 may include: a second writing module 32, a first reference module 31, a second threshold compensation module 33, a second coupling module 34, a second discharge module 35 and a second reference module 36; the control end of the second writing module 32 is connected to the first scanning signal step1; the second writing module 32 is used to connect the first power supply signal VGH and the second node N2; the first node N1 is respectively connected to the control ends of the first reference module 31 and the second reference module 36; the second threshold compensation module 33 is used to connect the second node N2 and the first end of the first reference module 31 in response to the second scanning signal step2; the second threshold compensation module 33 also Used to connect the second end of the first reference module 31 and the second level output terminal V2 in response to the second scanning signal step2; the first end of the second reference module 36 is connected to the first level output terminal V1; the second end of the second reference module 36 is used as the reference current signal output terminal; the second discharge module 35 is used to connect the first end of the first reference module 31 and the first power supply signal VGH in response to the third scanning signal step3; the second discharge module 35 is also used to affect the connection between the second end of the first reference module 31 and the second power supply signal VGL in the third scanning signal step3; the first end of the second coupling module 34 is connected to the third scanning signal step3; the second end of the second coupling module 34 is connected to the second node N2.

[0048] In the present embodiment, the first reference signal module 112 and the second reference signal module 122 can both output reference current signals, and both include the first reference module 31 and the second reference module 36. The first reference module 31 and the second reference module 36 can be unaffected by the ambient brightness and only change according to the driving signal, and can also be considered as current signals under zero ambient brightness. The reference current signals output by the first reference module 31 and the second reference module 36 do not change with the brightness, and are only reference values ​​that reflect the circuit settings. It should be noted that in the present embodiment, the circuit of the first reference signal module 112 is the same as the circuit of the first light sensing measurement module 111, and the second reference signal module 122 is the same as the circuit of the second light sensing measurement module 121. The only difference is that the first reference module 31 and the second reference module 36 are not photosensitive devices, and the first light sensing module 21 and the second light sensing module 26 are photosensitive devices. Furthermore, the circuit of the first reference signal module 112 is connected to the same driving signal (VGH, VGL, V1, V2, step1, step2 and step3) as the first light sensing measurement module 111. Similarly, the second reference signal module 122 is connected to the same driving signal as the second light sensing measurement module 121 to further improve the accuracy of the current ratio, thereby improving the accuracy of the ambient brightness measurement.

[0049] In the reference signal module, the second writing module 32 can affect the first scanning signal step1 to write the first power supply signal VGH to the first node N1, and turn on the first reference module 31 and the second reference module 36 at the same time; the second threshold compensation module 33 can respond to the second scanning signal step2 to write the second level and the threshold voltage of the first reference module 31 into the first node N1, so as to prevent the threshold voltage of the first reference module 31 from affecting the photosensitive current signal; in addition, the second coupling module 34 can respond to the third scanning signal step3 to couple and increase the potential of the first node N1. In order to keep the control terminal voltages of the first reference module 31 and the second reference module 36 consistent, so that the control terminal voltage of the second reference module 36 can be obtained through the first reference module 31, when the second reference module 36 is turned on, the first reference module 31 can also remain turned on, and the second discharge module 35 can provide a discharge circuit for the first reference module 31 to be turned on.

[0050] Continue to refer Figure 4 and Figure 5Optionally, the first writing module 22 may include a third transistor T3; the first light sensing module 21 includes a second transistor T2; the first threshold compensation module 23 includes a fourth transistor T4 and a fifth transistor T5; the first coupling module 24 includes a first capacitor C1; the first discharge module 25 includes a first transistor T1 and a seventh transistor T7; the second light sensing module 26 includes a sixth transistor T6; the control end of the third transistor T3 is connected to the first scanning signal step1; the first end of the third transistor T3 is connected to the first power supply signal VGH; the second end of the third transistor T3 is connected to the first node N1; the first node N1 is respectively connected to the control ends of the second transistor T2 and the sixth transistor T6; the control ends of the fourth transistor T4 and the fifth transistor T5 are both connected to the second scanning signal step2; the fourth transistor T4 is used for The first node N1 is connected to the first end of the second transistor T2; the fifth transistor T5 is used to connect the second end of the second transistor T2 and the second level output end V2; the first end of the sixth transistor T6 is connected to the first level output end V1; the second end of the sixth transistor T6 is used as the light-sensing current signal output end; the control ends of the first transistor T1 and the seventh transistor T7 are connected to the third scanning signal step3; the first end of the seventh transistor T7 is connected to the first power signal VGH; the second end of the seventh transistor T7 is connected to the first end of the second transistor T2; the first end of the first transistor T1 is connected to the second end of the second transistor T2; the second end of the first transistor T1 is connected to the second power signal VGL; the first end of the first capacitor C1 is connected to the third scanning signal step3; the second end of the first capacitor C1 is connected to the first node N1.

[0051] Figure 6 for Figure 4 The driving timing diagram of the pre-detection light sensing circuit is similar. Figure 6 Also for Figure 5 Optionally, in the same pre-detection light sensing circuit 11 or the precise detection light sensing circuit 12, the first scanning signal step1, the second scanning signal step2 and the third scanning signal step3 are configured to output valid pulses in sequence; in the first scanning signal step1, the second scanning signal step2 and the third scanning signal step3, the time periods of the valid pulses of any two scanning signals do not overlap. It should be noted that Figure 4 and Figure 5 The transistors in the circuit shown are all illustrated by N-type transistors, which are turned on at a high level and turned off at a low level, and the effective pulse is a high level. Of course, the above transistors can also be P-type transistors, and the effective pulse is a low level.

[0052] Figure 7 for Figure 4 The schematic diagram of the state of the pre-detection light sensing circuit in the first stage. Figure 8 for Figure 4The schematic diagram of the state of the pre-detection light sensing circuit in the second stage, Fig. 9 for Figure 4 Schematic diagram of another state of the pre-detection light sensing circuit in the second stage, Fig.10 for Figure 4 The schematic diagram of the state of the pre-detection light sensing circuit in the third stage. Figure 7 for Figure 5 The state diagram of the precise detection light sensing circuit in the first stage. Figure 8 for Figure 5 The state diagram of the precise detection light sensing circuit in the second stage, Fig. 9 for Figure 5 Schematic diagram of another state of the precise detection light sensing circuit in the second stage. Fig.10 for Figure 5 Schematic diagram of accurately detecting the state of the light sensing circuit in the third stage. In this embodiment, an ambient brightness detection process of the first light sensing measurement module 111 or the second light sensing measurement module 121 is divided into three stages: the first stage, the second stage and the third stage. Specifically, the first scanning signal step1, the second scanning signal step2 and the third scanning signal step3 are configured as follows: in the first stage, the third transistor T3 is turned on by the first scanning signal step1, so that the first power supply signal VGH is injected into the gates of the second transistor T2 and the sixth transistor T6, that is, the first node N1. At this time, the second transistor T2, the third transistor T3 and the sixth transistor T6 are turned on, and the first transistor T1, the fourth transistor T4, the fifth transistor T5 and the seventh transistor T7 are turned off; in the second stage, the fourth transistor T4 and the fifth transistor T5 are turned on by the second scanning signal step2, as shown in FIG. Figure 8 As shown, in the first sub-stage of the second stage, the second transistor T2, the fourth transistor T4, the fifth transistor T5 and the sixth transistor T6 are turned on, and the first transistor T1, the third transistor T3 and the seventh transistor T7 are turned off, then the charge of the first node N1 passes through the fourth transistor T4, the second transistor T2 and the fifth transistor T5 in sequence to reach the second voltage output terminal V2, because the second voltage of the second voltage output terminal V2 is less than the voltage of the first node N1 (the initial moment is VGH), the voltage of the first node N1 gradually decreases until the voltage of the first node N1 drops to V2+Vth, wherein Vth is the threshold voltage of the second transistor T2, and the charge of the first node N1 cannot continue to flow to the second voltage output terminal V2, so far, as shown in FIG. Fig. 9As shown, the second sub-stage of the second stage is entered. At this time, the fourth transistor T4, the fifth transistor T5 and the sixth transistor T6 are turned on, and the first transistor T1, the second transistor T2, the third transistor T3 and the seventh transistor T7 are turned off. Because the working states of the second transistor T2 and the sixth transistor T6 are always synchronized (the gate voltage is the same, the turn-on time is the same), and both are illuminated by ambient light, the threshold voltage of the second transistor T2 is approximately the threshold voltage of the sixth transistor T6, so that the voltage of the first node N1 is approximately related to the threshold voltage of the sixth transistor T6; in the third stage, the first transistor T2 is turned on by the third scanning signal step3. At this time, the first transistor T1, the second transistor T2, the sixth transistor T6 and the seventh transistor T7 are turned on, the third transistor T3, the fourth transistor T4 and the fifth transistor T5 are turned off, and the voltage of the first node N1 is coupled up by the first capacitor C1, because the voltage of the first node N1 already includes the threshold voltage of the sixth transistor T6, therefore, the coupling of the first capacitor C1 no longer needs to consider the influence of the threshold voltage, and the first voltage output terminal V1 outputs the light-sensitive current signal to the light-sensitive current signal output terminal through the sixth transistor T6. At this point, the entire light-sensitive measurement module realizes the adaptation of the light-sensitive TFT threshold voltage.

[0053] Optionally, the second writing module 32 includes a ninth transistor T9; the first reference module 31 includes a tenth transistor T10; the second threshold compensation module 33 includes an eleventh transistor T11 and a twelfth transistor T12; the second coupling module 34 includes a second capacitor C2; the second discharge module 35 includes a fourteenth transistor T14 and a fifteenth transistor T15; the second reference module 36 includes a thirteenth transistor T13; the control end of the ninth transistor T9 is connected to the first scanning signal step1; the first end of the ninth transistor T9 is connected to the first power supply signal VGH; the second end of the ninth transistor T9 is connected to the second node N2; the second node N2 is respectively connected to the control ends of the tenth transistor T10 and the thirteenth transistor T13; the control ends of the eleventh transistor T11 and the twelfth transistor T12 are both connected to the second scanning signal step2; the eleventh transistor T11 is used to connect The second node N2 and the first end of the tenth transistor T10; the twelfth transistor T12 is used to connect the second end of the tenth transistor T10 and the second level output end V2; the first end of the thirteenth transistor T13 is connected to the first level output end V1; the second end of the thirteenth transistor T13 is used as a reference current signal output end; the control ends of the fifteenth transistor T15 and the fourteenth transistor T14 are connected to the third scanning signal step3; the first end of the fourteenth transistor T14 is connected to the first power signal VGH; the second end of the fourteenth transistor T14 is connected to the first end of the tenth transistor T10; the first end of the fifteenth transistor T15 is connected to the second end of the tenth transistor T10; the second end of the fifteenth transistor T15 is connected to the second power signal VGL; the first end of the second capacitor C2 is connected to the third scanning signal step3; the second end of the second capacitor C2 is connected to the second node N2.

[0054] Similarly, an environment brightness detection process of the first reference signal module 112 and the second reference signal module 122 is divided into three stages: a first stage, a second stage and a third stage. Specifically, the first scanning signal step1, the second scanning signal step2 and the third scanning signal step3 are configured as follows: in the first stage, the tenth transistor T10, the ninth transistor T9 and the thirteenth transistor T13 are turned on, and the fifteenth transistor T15, the eleventh transistor T11, the twelfth transistor T12 and the fourteenth transistor T14 are turned off; in the first sub-stage of the second stage, the tenth transistor T10, the eleventh transistor T11, the twelfth transistor T12 and the thirteenth transistor T13 are turned on, and the fifteenth transistor T15, the ninth transistor T9 and the fourteenth transistor T14 are turned off; in the second sub-stage of the second stage, the eleventh transistor T11, the twelfth transistor T12 and the thirteenth transistor T13 are turned on, and the fifteenth transistor T15, the tenth transistor T10, the ninth transistor T9 and the fourteenth transistor T14 are turned off; in the third stage, the fifteenth transistor T15, the tenth transistor T10, the thirteenth transistor T13 and the fourteenth transistor T14 are turned on, and the ninth transistor T9, the eleventh transistor T11 and the twelfth transistor T12 are turned off.

[0055] Continue to refer Figure 5 Optionally, the enabling module 123 for accurately detecting the light sensing circuit 12 may include: an eighth transistor T8 and a sixteenth transistor T16; the control end of the eighth transistor T8 is connected to the enabling signal; the first end of the eighth transistor T8 is connected to the first node N1; the second end of the eighth transistor T8 is connected to the second power supply signal VGL; the control end of the sixteenth transistor T16 is connected to the enabling signal; the first end of the sixteenth transistor T16 is connected to the second node N2; the second end of the sixteenth transistor T16 is connected to the second power supply signal VGL.

[0056] If the eighth transistor T8 and the sixteenth transistor T16 are both N-type transistors, the eighth transistor T8 and the sixteenth transistor T16 are controlled to be turned on when the enable signal is at a high level, and the potentials of the first node N1 and the second node N2 are directly pulled down to the second power supply signal VGL, then the sixth transistor T6 and the thirteenth transistor T13 are not turned on, and no second light-sensing current signal and second reference current signal are output, and at this time, the precise detection light-sensing circuit 12 does not measure the ambient brightness. When the enable signal is at a low level, the eighth transistor T8 and the sixteenth transistor T16 cannot be turned on, and the precise detection light-sensing circuit 12 can measure the ambient brightness.

[0057] Continue to refer Figures 7 to 10Optionally, in the same pre-detection photosensitive circuit 11 or precise detection photosensitive circuit 12, the first photosensitive module 21 and the second photosensitive module 26 have the same conduction timing; the first reference module 31 and the second reference module 36 have the same conduction timing. Because the threshold voltage of the second photosensitive module 26 needs to be obtained through the threshold voltage of the first photosensitive module 21, the present embodiment always keeps the conduction timing of the first photosensitive module 21 and the second photosensitive module 26 the same, so that the gate voltage and conduction time of the first photosensitive module 21 and the second photosensitive module 26 are equal, and the threshold voltage of the first photosensitive module 21 can be approximately used as the threshold voltage of the second photosensitive module 26, and the above threshold voltage is loaded to the control end of the second photosensitive module 26, that is, the first node N1, to improve the accuracy of the output photosensitive current signal so that it is not affected by the threshold voltage. Similarly, the first reference module 31 and the second reference module 36 serve as current signal comparison values ​​of a black state environment, and their conduction timings remain consistent, so that the reference signal module and the light sensing measurement module work in completely consistent states. The only difference is whether they are affected by the ambient brightness, thereby further improving the accuracy of the reference circuit signal and the accuracy of the current ratio, thereby ultimately improving the detection accuracy of the ambient brightness.

[0058] Optionally, the second level V21 output by the second level output terminal V2 connected to the pre-detection photosensitive circuit 11 is different from the second level V22 output by the second level output terminal V2 connected to the precise detection photosensitive circuit 12. In order to realize that the pre-detection photosensitive circuit 11 and the precise detection photosensitive circuit 12 have different detection accuracy and detection range, it is necessary to control the voltage value of the first node N1 to be different, and the voltage value of the first node N1 includes the second level, the threshold voltage of the second photosensitive module 26, and the coupling voltage of the first coupling module. Therefore, this embodiment can control the second level connected to the pre-detection photosensitive circuit 11 and the precise detection photosensitive circuit 12 to be different. In this embodiment, if the pre-detection photosensitive circuit 11 is connected to the second level V21 and the precise detection photosensitive circuit 12 is connected to the second level V22, this embodiment sets V21 and V22 to different values.

[0059] Optionally, V21<V22. Generally, the higher the first node N1 (the gate voltage of the second light sensing module 26), the lower the measurement accuracy. Figures 11 to 14 As shown, Fig.11 A schematic diagram of a first current ratio range where the first node potential is -25 to 5 V provided by an embodiment of the present invention, Fig.12 A schematic diagram of a first current ratio range in which the first node potential is 5 to 12 V provided by an embodiment of the present invention, Fig.13 A schematic diagram of a first current ratio range in which the first node potential is 12 to 25 V provided in an embodiment of the present invention, Fig.14A schematic diagram of a first current ratio range of a first node potential of 25 to 40 V provided in an embodiment of the present invention, wherein the abscissa is the potential of the first node N1, which is also the gate voltage Vgs of the second photosensitive module 26, and the ordinate is the first current ratio value of the first photosensitive current signal to the first reference current signal when the first photosensitive current signal is 160 mA, Fig.11 It can be seen that when the first node potential is a negative value, between -20 and 5V, the first current ratio takes a larger value, and the current ratio range is also large, so its accuracy is low. When it is in the range of 5V to 15V, the first current ratio takes a smaller value, and the current ratio range is also small, so its accuracy is high. Although the value range of the first current ratio from 25V to 40V is small, its fluctuation is large, and the value accuracy is not high. In this embodiment, the greater the gate voltage, the smaller the value accuracy of the ambient brightness. In this embodiment, V21<V22 can be set, so that the detection accuracy of the precise detection photosensitive circuit 12 is higher than the detection accuracy of the pre-detection photosensitive circuit 11.

[0060] Optionally, the capacitance values ​​of the first coupling module 24 and the second coupling module 34 of the pre-detection photosensitive circuit 11 are the same, both are C11; the capacitance values ​​of the first coupling module 24 and the second coupling module 34 of the precise detection photosensitive circuit 12 are the same, both are C12; wherein C11 is different from C12. Similarly, because the voltage value of a node N1 includes the second level, the threshold voltage of the second photosensitive module 26, and the coupling voltage of the first coupling module, this embodiment can achieve different ranges and different measurement accuracies by controlling the capacitance values ​​of the coupling modules (the first coupling module 24 and the second coupling module 34) of the pre-detection photosensitive circuit 11 and the precise detection photosensitive circuit 12 to be different. Optionally, C11<C12, so that the detection accuracy of the precise detection photosensitive circuit 12 is higher than the detection accuracy of the pre-detection photosensitive circuit 11.

[0061] An embodiment of the present invention further provides a display device. Fig.15 A schematic diagram of a display device according to an embodiment of the present invention is shown in FIG. Fig.15 As shown, the electronic device provided by the embodiment of the present invention includes the display panel 200 described in any embodiment of the present invention. The electronic device can be as follows Fig.15 The mobile phone shown in the figure may also be a computer, a television, a smart wearable device, etc., and this embodiment does not specifically limit this.

[0062] The display device provided by the embodiment of the present invention includes the technical features of the display panel provided by any embodiment of the present invention, and has the beneficial effects possessed by the corresponding features, which will not be described in detail here.

[0063] Note that the above are only preferred embodiments of the present invention and the technical principles used. Those skilled in the art will understand that the present invention is not limited to the specific embodiments described herein, and that various obvious changes, readjustments and substitutions can be made by those skilled in the art without departing from the scope of protection of the present invention. Therefore, although the present invention has been described in more detail through the above embodiments, the present invention is not limited to the above embodiments, and may include more other equivalent embodiments without departing from the concept of the present invention, and the scope of the present invention is determined by the scope of the appended claims.

Claims

1. A display panel, characterized in that: include: Pre-detection light sensing circuit, multiple precision detection light sensing circuits and driver chips; The pre-detection light sensing circuit is used to obtain a first light sensing current signal of the ambient brightness; The driver chip is connected to the pre-detection light sensing circuit, and is used to send an enable signal to the corresponding precise detection light sensing circuit according to the first light sensing current signal, so that the precise detection light sensing circuit obtains a second light sensing current signal of the ambient brightness; The driving chip is also used to obtain an ambient brightness measurement value according to the second light-sensing current signal; The step current signal of the pre-detection light sensing circuit is greater than the step current signal of the precise detection light sensing circuit; The pre-detection light sensing circuit comprises: a first light sensing measurement module and a first reference signal module; The first light sensing measurement module is used to generate a first light sensing current signal according to the ambient brightness; the first reference signal module is used to generate a first reference current signal according to the zero brightness state; The driver chip is specifically used to: obtain the first photosensitive current signal and the first reference current signal; use the ratio of the first photosensitive current signal to the first reference current signal as the first current ratio; obtain an accurate detection photosensitive circuit whose measurement range covers the first current ratio, and send an enable signal to it.

2. The display panel according to claim 1, characterized in that: The precise detection light sensing circuit comprises: a second light sensing measurement module, a second reference signal module and an enabling module; The enabling module is used to control the second light sensing measurement module and the second reference signal module to measure the current signal according to the enabling signal; the second light sensing measurement module is used to generate a second light sensing current signal according to the ambient brightness; the second reference signal module is used to generate a second reference current signal according to the zero brightness state; The driving chip is specifically used for: obtaining the second light-sensitive current signal and the second reference current signal; taking the ratio of the second light-sensitive current signal to the second reference current signal as the second current ratio; and obtaining an ambient brightness measurement value according to the second current ratio.

3. The display panel according to claim 2, characterized in that: The first light sensing measurement module and the second light sensing measurement module both include: a first writing module, a first light sensing module, a first threshold compensation module, a first coupling module, a first discharge module and a second light sensing module; The control end of the first writing module is connected to the first scanning signal; the first writing module is used to connect the first power signal and the first node; the first node is respectively connected to the control ends of the first light sensing module and the second light sensing module; The first threshold compensation module connects the first node and the first end of the first light sensing module in response to the second scanning signal; the first threshold compensation module also connects the second end of the first light sensing module and the second level output end in response to the second scanning signal; the first end of the second light sensing module is connected to the first level output end; the second end of the second light sensing module is used as a light sensing current signal output end; The first discharge module connects the first end of the first light sensing module and the first power signal in response to the third scanning signal; the first discharge module also connects the second end of the first light sensing module and the second power signal in response to the third scanning signal; The first end of the first coupling module is connected to the third scanning signal; the second end of the first coupling module is connected to the first node.

4. The display panel according to claim 3, characterized in that: The first reference signal module and the second reference signal module both include: a second writing module, a first reference module, a second threshold compensation module, a second coupling module, a second discharge module and a second reference module; The control end of the second writing module is connected to the first scanning signal; the second writing module is used to connect the first power signal and the second node; the first node is respectively connected to the control end of the first reference module and the second reference module; The second threshold compensation module is used to connect the second node and the first end of the first reference module in response to the second scan signal; the second threshold compensation module is also used to connect the second end of the first reference module and the second level output end in response to the second scan signal; the first end of the second reference module is connected to the first level output end; the second end of the second reference module is used as a reference current signal output end; The second discharge module is used to connect the first end of the first reference module and the first power signal in response to the third scan signal; the second discharge module is also used to affect the connection of the second end of the first reference module and the second power signal by the third scan signal; The first end of the second coupling module is connected to the third scanning signal; the second end of the second coupling module is connected to the second node.

5. The display panel according to claim 3, characterized in that: The first writing module includes a third transistor; the first light sensing module includes a second transistor; the first threshold compensation module includes a fourth transistor and a fifth transistor; the first coupling module includes a first capacitor; the first discharge module includes a first transistor and a seventh transistor; the second light sensing module includes a sixth transistor; The control end of the third transistor is connected to the first scanning signal; the first end of the third transistor is connected to the first power supply signal; the second end of the third transistor is connected to the first node; the first node is connected to the control ends of the second transistor and the sixth transistor respectively; the control ends of the fourth transistor and the fifth transistor are both connected to the second scanning signal; the fourth transistor is used to connect the first node and the first end of the second transistor; the fifth transistor is used to connect the second end of the second transistor and the second level output end; the first end of the sixth transistor is connected to the first level output end; the second end of the sixth transistor is used as the light-sensing current signal output end; The control ends of the first transistor and the seventh transistor are connected to the third scanning signal; the first end of the seventh transistor is connected to the first power signal; the second end of the seventh transistor is connected to the first end of the second transistor; the first end of the first transistor is connected to the second end of the second transistor; the second end of the first transistor is connected to the second power signal; The first end of the first capacitor is connected to the third scanning signal; the second end of the first capacitor is connected to the first node.

6. The display panel according to claim 4, characterized in that: The second writing module includes a ninth transistor; the first reference module includes a tenth transistor; the second threshold compensation module includes an eleventh transistor and a twelfth transistor; the second coupling module includes a second capacitor; the second discharge module includes a fourteenth transistor and a fifteenth transistor; The second reference module includes a thirteenth transistor; The control end of the ninth transistor is connected to the first scanning signal; the first end of the ninth transistor is connected to the first power supply signal; the second end of the ninth transistor is connected to the second node; the second node is respectively connected to the control ends of the tenth transistor and the thirteenth transistor; the control ends of the eleventh transistor and the twelfth transistor are both connected to the second scanning signal; the eleventh transistor is used to connect the second node and the first end of the tenth transistor; the twelfth transistor is used to connect the second end of the tenth transistor and the second level output end; the first end of the thirteenth transistor is connected to the first level output end; the second end of the thirteenth transistor is used as a reference current signal output end; The control ends of the fifteenth transistor and the fourteenth transistor are connected to the third scan signal; the first end of the fourteenth transistor is connected to the first power signal; the second end of the fourteenth transistor is connected to the first end of the tenth transistor; the first end of the fifteenth transistor is connected to the second end of the tenth transistor; the second end of the fifteenth transistor is connected to the second power signal; A first end of the second capacitor is connected to the third scanning signal; and a second end of the second capacitor is connected to the second node.

7. The display panel according to claim 4, characterized in that: The enabling module of the precise detection light sensing circuit comprises: an eighth transistor and a sixteenth transistor; The control terminal of the eighth transistor is connected to the enable signal; the first terminal of the eighth transistor is connected to the first node; the second terminal of the eighth transistor is connected to the second power signal; The control end of the sixteenth transistor is connected to the enable signal; the first end of the sixteenth transistor is connected to the second node; and the second end of the sixteenth transistor is connected to a second power signal.

8. The display panel according to claim 4, characterized in that: In the same pre-detection light sensing circuit or the precise detection light sensing circuit, the first scanning signal, the second scanning signal and the third scanning signal are configured to output valid pulses in sequence; Among the first scanning signal, the second scanning signal and the third scanning signal, time periods of effective pulses of any two scanning signals do not overlap.

9. The display panel according to claim 4, characterized in that: In the same pre-detection photosensor circuit or the precise detection photosensor circuit, the first photosensor module and the second photosensor module have the same turn-on timing; the first reference module and the second reference module have the same turn-on timing.

10. The display panel according to claim 4, characterized in that: The second level V21 outputted from the second level output terminal connected to the pre-detection light sensing circuit is different from the second level V22 outputted from the second level output terminal connected to the precise detection light sensing circuit.

11. The display panel according to claim 10, characterized in that: V21<V22.

12. The display panel according to claim 4, characterized in that: The capacitance values ​​of the first coupling module and the second coupling module of the pre-detection photosensor circuit are the same, both are C11; the capacitance values ​​of the first coupling module and the second coupling module of the precise detection photosensor circuit are the same, both are C12; wherein C11 is different from C12.

13. The display panel according to claim 12, characterized in that: C11<C12.

14. A display device, characterized in that: A display panel comprising any one of claims 1-13.

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