Pixel driving circuit, display panel and display device

Abstract

The invention discloses a pixel driving circuit, a display panel and a display device. The pixel driving circuit comprises a display driving circuit, a display light-emitting unit, a peep-proof driving circuit and a peep-proof light-emitting unit in each pixel area. The display driving circuit comprises a first active switch and a first node, the peep-proof driving circuit comprises a second active switch, the control end of the first active switch and the control end of the second active switch are connected to the first node, the first node is used for receiving data signals, and the second node is used for receiving the data signals. The first node is used for controlling the first active switch to drive the display light-emitting unit to emit light and controlling the second active switch to drive the peep-proof light-emitting unit to emit light; and the peep-proof light-emitting unit and the display light-emitting unit are controlled to emit light under the same data signal. The peep-proof driving circuit and the display driving circuit are enabled to be peep-proof under the control of the first node, so that the complexity of the peep-proof control circuit is reduced while the peep-proof and display functions are realized.

Description

Technical Field

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

[0002] OLED organic light-emitting display technology has gradually matured, and as a self-luminous display technology, it is increasingly widely used in products. As people in modern society pay more attention to their own privacy, the anti-peeping function of the display panel has also become a necessary function of the product. Therefore, OLED anti-peeping technology has also been a hot topic of discussion recently. The traditional anti-peeping display is to attach an anti-peeping film to the surface of the display panel. The anti-peeping film generally uses ultra-fine blinds technology, and the principle is similar to that of vertical blinds. The display with the function of limiting the light to be emitted from the display panel at a fixed angle is the simplest and most direct solution, with a higher yield and the widest application. However, the anti-peeping film will also cause a great loss of light efficiency, an increase in power consumption, and the anti-peeping function cannot be turned off. At present, the anti-peeping light source can be set in the pixel area to interfere with the emitted light at a large viewing angle, and the anti-peeping function can be turned off by turning off the anti-peeping light source.

[0003] However, due to the increase of anti-peeping light sources, additional driving circuits, data lines, control lines, etc. need to be added, resulting in increased wiring complexity of the display panel. Summary of the invention

[0004] The purpose of the present application is to provide a pixel driving circuit, a display panel and a display device, by arranging an anti-peeping driving circuit and a display driving circuit to be connected to a first node respectively, so that the anti-peeping driving circuit and the display driving circuit are protected from peeping under the control of the first node, so that the anti-peeping and display functions are achieved while reducing the complexity of the anti-peeping control circuit.

[0005] The present application discloses a pixel driving circuit, which includes a display driving circuit, a display light-emitting unit, an anti-peeping driving circuit and an anti-peeping light-emitting unit in each pixel area; the display driving circuit includes a first active switch and a first node, the anti-peeping driving circuit includes a second active switch, the control ends of the first active switch and the second active switch are respectively connected to the first node, the first node is used to receive a data signal, the first node is used to control the first active switch to drive the display light-emitting unit to emit light, and control the second active switch to drive the anti-peeping light-emitting unit to emit light; the anti-peeping light-emitting unit and the display light-emitting unit are controlled to emit light under the same data signal.

[0006] Optionally, the display driving circuit also includes a third active switch and a first capacitor, the input end of the third active switch is externally connected to an external compensation circuit, the output end of the third active switch is connected to a second node, one end of the display light-emitting unit is connected to the second node, and the output end of the first active switch is connected to the second node; one end of the first capacitor is connected to the first node, and the other end of the first capacitor is connected to the second node; the external compensation circuit is used to detect the voltage of the second node through the third active switch and compensate for the input data signal of the first node; the anti-peeping light-emitting unit works under the drive of the compensated data signal of the first node.

[0007] Optionally, the anti-peeping drive circuit also includes a fourth active switch, the input end of the fourth active switch is connected to the first node, and the output end of the fourth active switch is connected to the control end of the second active switch; the fourth active switch is used to control the conduction or disconnection between the first node and the control end of the second active switch; the display drive circuit also includes a fifth active switch, the output end of the fifth active switch is connected to the first node, and the input end of the fifth active switch is connected to the data signal; the input end of the second active switch is connected to the anti-peeping control signal, and the input end of the first active switch is connected to the power supply voltage signal.

[0008] Optionally, input ends of a plurality of the second active switches are respectively connected to the same anti-peeping control signal.

[0009] Optionally, the pixel driving circuit further includes a first control signal, a second control signal and a third control signal, the first control signal is connected to the control end of the fourth active switch, the second control signal is connected to the control end of the fifth active switch, and the third control signal is connected to the control end of the third active switch; the pixel driving circuit includes a reset period, a write period and a display period, in the reset period, the third control signal is at a conduction level, the third active switch is turned on, and the second node is reset; in the write period, the second control signal and the first control signal are respectively at a conduction level, the fifth active switch and the fourth active switch are turned on, the first node inputs the compensated data signal, and the control end of the second active switch is turned on after receiving the compensated data signal of the first node; in the display period, the first active switch is turned on, and the display light-emitting unit emits light; under the control of the anti-peeping control signal, the anti-peeping light-emitting unit emits light.

[0010] Optionally, the pixel driving circuit includes a first control signal and a second control signal, and the anti-peeping driving circuit also includes a second capacitor, one end of the second capacitor is connected to the control end of the second active switch, and the other end of the second capacitor is connected to the output end of the second active switch; the first control signal is respectively connected to the control end of the fourth active switch and the control end of the fifth active switch, and the second control signal is connected to the control end of the third active switch; the pixel driving circuit includes a reset period, a write period and a display period, in the reset period, the second control signal is at a conduction level, the third active switch is turned on, and the second node is reset; in the write period, the first control signal is at a conduction level, the fifth active switch and the fourth active switch are turned on, the first node inputs the compensated data signal, and the control end of the second active switch is turned on after receiving the compensated data signal of the first node; in the display period, the first active switch is turned on, and the display light-emitting unit emits light; under the control of the anti-peeping control signal, the anti-peeping light-emitting unit emits light.

[0011] Optionally, the pixel driving circuit includes a first control signal, and the anti-peeping driving circuit also includes a second capacitor, one end of the second capacitor is connected to the control end of the second active switch, and the other end of the second capacitor is connected to the output end of the second active switch; the first control signal is respectively connected to the control end of the third active switch, the control end of the fourth active switch and the control end of the fifth active switch; the pixel driving circuit includes a reset writing period and a display period, in which the first control signal is at a conduction level, the third active switch, the fourth active switch and the fifth active switch are turned on, and after a delay of a preset time, the compensated data signal is written from the first node; in the display period, the first active switch and the second active switch are respectively turned on, and the display light-emitting unit and the anti-peeping light-emitting unit are respectively illuminated.

[0012] The present application also discloses a display panel, comprising a base substrate and the above-mentioned pixel driving circuit, wherein the pixel driving circuit layer is arranged on the base substrate, and the display panel further comprises a light-emitting unit layer and a light-shielding layer. The light-emitting unit layer is arranged on the pixel driving circuit layer, and comprises a plurality of display light-emitting units and a plurality of anti-peeping light-emitting units; the light-shielding layer is arranged on the light-emitting unit layer, and comprises a plurality of light-shielding portions, and the light-shielding portions are arranged corresponding to the anti-peeping light-emitting units.

[0013] Optionally, at least one display light-emitting unit and one anti-peeping light-emitting unit are provided in the same pixel area, and the anti-peeping light-emitting unit and the display light-emitting unit have different light-emitting colors.

[0014] The present application also discloses a display device, comprising a driving circuit board and the above-mentioned display panel, wherein the driving circuit board is used to provide a data signal to the pixel driving circuit to drive the display panel to display.

[0015] The present application sets a separate anti-peeping light-emitting unit and an anti-peeping driving circuit in each pixel area, and controls the anti-peeping driving circuit through the first node, so that when the display light-emitting unit in the current pixel area emits light, the anti-peeping light-emitting unit in the current pixel area also emits light. Through the control of the first node, the synchronous light emission of the anti-peeping light-emitting unit and the display light-emitting unit is realized. When the display light-emitting unit performs light-emitting display, the light emission of the anti-peeping light-emitting unit is used to interfere with the display under a large viewing angle, thereby realizing the anti-peeping function. By adding a second active switch and connecting the control end of the second active switch to the first node, the problem that the anti-peeping light-emitting unit needs to set up an additional driving circuit is solved. The anti-peeping driving circuit can be synchronously controlled through the data line and control line in the display driving circuit, reducing the wiring complexity of the display panel and improving the display effect and anti-peeping capability of the display panel. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] The included drawings are used to provide a further understanding of the embodiments of the present application, which constitute a part of the specification, are used to illustrate the implementation methods of the present application, and together with the text description, explain the principles of the present application. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work. In the drawings:

[0017] Figure 1 is a schematic diagram of a pixel driving circuit of the present application;

[0018] Figure 2 is a schematic diagram of a display panel of the present application;

[0019] Figure 3 is a schematic diagram of a pixel area of ​​the present application;

[0020] Figure 4 is a timing diagram of a pixel driving circuit of the first embodiment of the present application;

[0021] Figure 5 is a schematic diagram of a pixel driving circuit of a second embodiment of the present application;

[0022] Figure 6 is a timing diagram of a pixel driving circuit according to a second embodiment of the present application;

[0023] Figure 7 is a schematic diagram of a pixel driving circuit according to a third embodiment of the present application;

[0024] Figure 8 is a timing diagram of a pixel driving circuit according to a third embodiment of the present application;

[0025] Fig. 9 is a schematic diagram of a pixel driving circuit according to a fourth embodiment of the present application;

[0026] Fig.10 is a timing diagram of a pixel driving circuit according to a fourth embodiment of the present application;

[0027] Fig.11 is a schematic diagram of a display device of the present application.

[0028] Among them, 100, display panel; 110, pixel driving circuit; 111, display driving circuit; 112, display light-emitting unit; 113, anti-peeping driving circuit; 114, anti-peeping light-emitting unit; 121, substrate; 122, light-emitting unit layer; 123, shading portion; 130, pixel area; 131, anti-peeping sub-pixel; 132, display sub-pixel; 200, display device; 210, driving circuit board; N1, first node; N2, second node; T1, first active switch; T2, second active switch; T3, third active switch; T4, fourth active switch; T5, fifth active switch; C1, first capacitor; C2, second capacitor; Scan1, first control signal; Scan2, second control signal; Scan3, third control signal; Data, data signal; Vsen, reset signal. DETAILED DESCRIPTION

[0029] It should be understood that the terms used herein, the specific structures and functional details disclosed are only for describing specific embodiments and are representative, but the present application can be implemented in many alternative forms and should not be construed as being limited to only the embodiments described herein.

[0030] In the description of the present application, the terms "first" and "second" are used for descriptive purposes only and cannot be understood as indicating relative importance or implicitly indicating the number of technical features indicated. Therefore, unless otherwise specified, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features; "multiple" means two or more. In addition, terms indicating orientation or positional relationships such as "upper", "lower", "left", "right", "vertical", and "horizontal" are described based on the orientation or relative positional relationships shown in the accompanying drawings, and are only simplified descriptions for the convenience of describing the present application, rather than indicating that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present application. For those of ordinary skill in the art, the specific meanings of the above terms in the present application can be understood according to the specific circumstances.

[0031] The present application is described in detail below with reference to the accompanying drawings and optional embodiments.

[0032] Figure 1 is a schematic diagram of the pixel driving circuit of the present application, see Figure 1 As shown, the present application discloses a pixel driving circuit 110, which includes a display driving circuit 111, a display light-emitting unit 112, an anti-peeping driving circuit 113 and an anti-peeping light-emitting unit 114 in each pixel area 130; the display driving circuit 111 includes a first active switch T1 and a first node N1, the anti-peeping driving circuit 113 includes a second active switch T2, the control ends of the first active switch T1 and the second active switch T2 are respectively connected to the first node N1, the first node N1 is used to receive a data signal Data, the first node N1 is used to control the first active switch T1 to drive the display light-emitting unit 112 to emit light, and control the second active switch T2 to drive the anti-peeping light-emitting unit 114 to emit light; the anti-peeping light-emitting unit 114 and the display light-emitting unit 112 are controlled to emit light under the same data signal Data.

[0033] The present application sets a separate anti-peeping light-emitting unit 114 and an anti-peeping driving circuit 113 in each pixel area 130, and controls the anti-peeping driving circuit 113 through the first node N1, so that when the display light-emitting unit 112 of the current pixel area 130 emits light, the anti-peeping light-emitting unit 114 in the current pixel area 130 also emits light. Through the control of the first node N1, the anti-peeping light-emitting unit 114 and the display light-emitting unit 112 are synchronized to emit light. When the display light-emitting unit 112 emits light, the anti-peeping light-emitting unit 114 is used to interfere with the display under a large viewing angle, thereby realizing the anti-peeping function. By adding a second active switch T2 and connecting the control end of the second active switch T2 to the first node N1, the problem that the anti-peeping light-emitting unit 114 needs to be additionally provided with a driving circuit is solved, and the control of the anti-peeping driving circuit 113 can be synchronously realized through the data line and the control line in the display driving circuit 111, thereby reducing the wiring complexity of the display panel 100 and improving the display effect and anti-peeping capability of the display panel 100.

[0034] It is worth mentioning that, compared with the exemplary solution of controlling the anti-peeping light-emitting unit 114 according to the grayscale signal of the display light-emitting unit when the anti-peeping light-emitting unit 114 and the display light-emitting unit 112 share a display driving circuit, for example, controlling the anti-peeping light-emitting unit 114 according to the anode or the second node N2 of the display light-emitting unit 112, due to the addition of the anti-peeping light-emitting unit 114, if the anti-peeping light-emitting unit is directly driven by the second node N2 or the control circuit of the anti-peeping light-emitting unit is indirectly connected to the anode end (the second node N2) of the display light-emitting unit, on the one hand, the driving capability of the display driving circuit 111 is insufficient, resulting in insufficient brightness of the display light-emitting unit 112. Moreover, when the grayscale of the display light-emitting unit 112 is different, the brightness of the corresponding anti-peeping light-emitting unit 114 will also be different. In addition, the above-mentioned insufficient driving capability of the display driving circuit 111 will further lead to inconsistent brightness of the anti-peeping light-emitting unit 114, especially the problem of insufficient anti-peeping capability in the low grayscale display area and excessive anti-peeping capability in the high grayscale display area. The present application mainly utilizes the first node N1 in the display driving circuit 111 to jointly drive the anti-peeping light-emitting unit 114 to display based on the pixel driving circuit 110. When the display light-emitting unit 112 of the current pixel area 130 is not lit, the anti-peeping light-emitting unit 114 also does not emit light. Among them, the second node N2 is directly connected to one end (generally the anode end) of the display light-emitting unit 112, avoiding the problem of poor light emission of the display light-emitting unit 112 caused by using the second node N2 as the control end of the anti-peeping light-emitting unit 114.

[0035] Figure 2 is a schematic diagram of a display panel of the present application, Figure 3 is a schematic diagram of the pixel area of ​​the present application, see Figures 2 to 3 As shown, the present application also discloses a display panel 100, which includes a substrate substrate 121 and the above-mentioned pixel driving circuit 110, wherein the pixel driving circuit 110 layer is arranged on the substrate, and the display panel 100 also includes a light-emitting unit layer 122 and a shading layer, wherein the light-emitting unit layer 122 is arranged on the pixel driving circuit 110 layer, and includes a plurality of display light-emitting units 112 and a plurality of anti-peeping light-emitting units 114; the shading layer is arranged on the light-emitting unit layer 122, and includes a plurality of shading portions 123, and the shading portions 123 are arranged corresponding to the anti-peeping light-emitting units 114.

[0036] In the present application, the pixel driving circuit 110 is generally disposed between the substrate 121 and the light emitting unit layer 122, and the pixel driving circuit 110 drives one or more sub-pixels in each pixel area 130 to emit light to form a display. The anti-peeping light emitting unit 114 can be formed in the light emitting unit layer 122 like the display light emitting unit 112, and light emission and shutoff are realized by the control of the thin film transistor.

[0037] In which, at least one display light emitting unit 112 and one anti-peeping light emitting unit 114 are disposed in the same pixel area 130 , and the anti-peeping light emitting unit 114 emits light of a different color from that of the display light emitting unit 112 .

[0038] The present application adds an additional anti-peeping light-emitting unit 114 in the pixel area 130, that is, an additional anti-peeping sub-pixel 131 is added to the pixel area 130. The display sub-pixel 132 in the pixel area 130 is generally provided with sub-pixels of three different colors, such as red sub-pixels, green sub-pixels and blue sub-pixels, so as to realize the display of any color. Among them, the red sub-pixel is provided with a display light-emitting unit 112 that emits red light or a red filter that makes the area emit red light. When a red filter is provided, the display light-emitting unit 112 can also be a light-emitting unit that emits white light. Similarly, green light is emitted from the position where the green sub-pixel is located, and blue light is emitted from the position where the blue sub-pixel is located. The anti-peeping sub-pixel 131 can be an anti-peeping light-emitting unit 114 of a different color from the above-mentioned red sub-pixel, green sub-pixel and blue sub-pixel. For example, a white light-emitting unit can be used as an anti-peeping light-emitting unit 114. A shading portion 123 is generally provided above the anti-peeping light unit 114 to block the light emitted from the anti-peeping light unit 114 perpendicularly or nearly perpendicularly to the base substrate 121, to prevent this part of the light from affecting the display of the front viewing angle. Generally speaking, the anti-peeping angle can be adjusted by adjusting the area of ​​the anti-peeping light unit 114 covered by the shading portion 123. The larger the area of ​​the shading layer, the closer the corresponding anti-peeping angle is to the wide viewing angle; when the area of ​​the shading layer is smaller, the range of the anti-peeping angle is larger.

[0039] When only one anti-peeping light emitting unit 114 is provided in a pixel area, the anti-peeping light emitting unit 114 is connected to the first node N1 of any display driving circuit 111 in the display area. The advantage is that there is no need to set up a complex connection line, and any display light emitting unit 112 can be selected, and the anti-peeping light emitting unit 114 can be turned on according to the turning on of the display light emitting unit 112.

[0040] In this embodiment, the anti-peeping light-emitting unit 114 can be arranged in parallel with the display sub-pixels 132 in the pixel area 130, or can be arbitrarily arranged between the three display sub-pixels 132, so as to realize the anti-peeping function of the anti-peeping light-emitting unit 114 on the pixel area 130. Of course, when the red sub-pixels, green sub-pixels and blue sub-pixels of the pixel area 130 are arranged horizontally, the anti-peeping sub-pixels 131 can be arranged above or below the three display sub-pixels 132.

[0041] However, there is a problem that the anti-peeping light-emitting unit 114 cannot work when one display light-emitting unit 112 in the current pixel area 130 does not emit light, while the other two display light-emitting units 112 partially or completely emit light. To solve this problem, the number of anti-peeping light-emitting units 114 in the pixel area 130 can be increased, such as increasing it to the same number as the display sub-pixels 132. That is, in each pixel area 130, the first node N1 of the display driving circuit 111 of each display light-emitting unit 112 is connected to an anti-peeping light-emitting unit 114.

[0042] Of course, considering that in actual display, it is not necessary for all the anti-peeping light-emitting units 114 in each pixel area 130 to work to have an anti-peeping effect, and increasing the number of anti-peeping light-emitting units 114 in each pixel area 130 will result in a reduction in the area occupied by the display light-emitting unit 112. Therefore, in actual design, only one anti-peeping light-emitting unit 114 is provided in each pixel area 130.

[0043] Continue to see Figure 1 As shown, specifically, the display driving circuit 111 also includes a third active switch T3 and a first capacitor C1, the input end of the third active switch T3 is externally connected to the external compensation circuit, the output end of the third active switch T3 is connected to the first node N1, one end of the display light-emitting unit 112 is connected to the first node N1, and the output end of the first active switch T1 is connected to the first node N1; one end of the first capacitor C1 is connected to the first node N1, and the other end of the first capacitor C1 is connected to the second node N2; the external compensation circuit is used to detect the voltage of the second node N2 through the third active switch T3, and compensate for the input data signal Data of the first node N1; the anti-peeping light-emitting unit 114 works under the drive of the compensated data signal Data of the first node N1.

[0044] Among them, the third active switch T3 of the present application is connected to an external compensation circuit, which is not arranged on the substrate 121, and is generally connected to the pixel driving circuit 110 in an external manner. The main function of the external compensation circuit is to input a specific data signal Data through the data line when the display panel 100 is tested, and to generate a compensation table or compensation data by sensing the current or voltage difference caused by the line resistance or the threshold voltage of the first active switch T1 from the third active switch T3. When the display panel 100 is displayed normally in the subsequent display, the above compensation signal is directly superimposed on the data signal Data through the external compensation circuit, so that the signal transmitted to the first node N1 is the compensated data signal Data, and the data signal Data is the data signal Data after the line resistance and capacitance interference are removed. Under the control of the compensated data signal Data, the anti-peeping light-emitting units 114 at different positions can overcome the uneven brightness caused by the drift of the wiring line resistance and the threshold voltage of the first active switch T1 over time, so that the anti-peeping light-emitting units 114 at different positions have a brightness closer to the display light-emitting unit 112.

[0045] It should be noted that although the embodiment of the present application only detects the output end of the first active switch T1 (i.e., the second node N2), and does not detect the output of the second active switch T2, and does not compensate separately, it can still achieve a relatively accurate compensation effect. This is because the anti-peeping drive circuit 113 in the embodiment of the present application is very close to the display drive circuit 111 to which it is connected, so the second active switch T2 and the first active switch T1 are less affected by process unevenness, and the initial threshold voltages of the two are close. And because the two share a common data voltage, the drift trend of the threshold voltages of the two is also close after long-term use. Therefore, only detecting the second node N2 and performing compensation together can simplify the detection and compensation steps, shorten the detection and compensation time, and enable it to be used in high refresh mode.

[0046] It is worth mentioning that due to the increase in the number of data lines, control lines, etc. of the current display panel 100, the data signal Data and control signal are attenuated due to line resistance, resulting in uneven brightness of the anti-peeping light-emitting unit 114. In actual situations, although the uneven brightness of the anti-peeping light-emitting unit 114 has little effect on the overall anti-peeping effect, if the brightness difference of the anti-peeping light-emitting unit 114 in different areas is too large, due to the refraction, reflection, diffraction and other effects of light, the shading layer cannot completely block the outgoing light of the anti-peeping light-emitting unit 114 at the normal viewing angle, and part of the light of the anti-peeping light-emitting unit 114 will be added to the display at the normal viewing angle, affecting the display effect at the normal viewing angle. At this time, if the brightness of the anti-peeping light-emitting unit 114 is uneven, there will be a difference in brightness and darkness at different positions. When the superimposed display sub-pixel 132 is displayed in different grayscales, the display difference at the normal viewing angle will increase, resulting in a poor display effect. In order to avoid the above problems, the present application controls the anti-peeping light-emitting unit 114 through the compensated data signal Data, so that the compensated data signal Data avoids the voltage drop caused by the interference of the line resistance or capacitance, and avoids the problem of uneven brightness of the anti-peeping light-emitting unit caused by the threshold voltage of the driving thin film transistor drifting over time. On the other hand, since the brightness of the anti-peeping light-emitting unit 114 overcomes the differences caused by the above-mentioned line resistance and threshold voltage, the anti-peeping effect at a wide viewing angle is also better, so that the displayed content cannot be seen at all at a wide viewing angle.

[0047] In order to better control the anti-peeping light-emitting unit 114, in this embodiment, the anti-peeping driving circuit 113 also includes a fourth active switch T4, the input end of the fourth active switch T4 is connected to the first node N1, and the output end of the fourth active switch T4 is connected to the control end of the second active switch T2; the fourth active switch T4 is used to control the conduction or disconnection between the first node N1 and the control end of the second active switch T2. In this embodiment, by additionally adding a fourth active switch T4 between the first node N1 and the control end of the second active switch T2, the fourth active switch T4 mainly controls whether the control end of the second active switch T2 is connected to the voltage of the first node N1. When anti-peeping display is not required, the anti-peeping switch can also be realized by controlling the conduction and cutoff of the fourth active switch T4.

[0048] Specifically, the display driving circuit 111 further includes a fifth active switch T5 , the output end of the fifth active switch T5 is connected to the first node N1 , and the input end of the fifth active switch T5 is connected to the data signal Data.

[0049] In the pixel driving circuit 110 of the present application, the input end of the second active switch T2 is connected to the anti-peeping control signal, and the input end of the first active switch T1 is connected to the power supply voltage signal. The first active switch T1 and the second active switch T2 are both field effect transistors, and the current output by the field effect transistor can be controlled by controlling the voltage of the gate. The third active switch T3, the fourth active switch T4 and the fifth active switch T5 are switch tubes, which only have the function of switches. Of course, the second active switch T2 can also be selected as a switch tube. Under different timing control, the second active switch T2 can realize the switch control of the anti-peeping light-emitting unit 114, and the brightness of the anti-peeping light-emitting unit 114 can be changed by controlling the anti-peeping control signal. When the second active switch T2 is a field effect transistor, the second active switch T2 outputs different currents to the anti-peeping light-emitting unit 114 according to the different potentials of the first node N1, thereby realizing that the anti-peeping light-emitting unit 114 has different brightness.

[0050] In an embodiment of the present application, input terminals of a plurality of the second active switches T2 are respectively connected to the same anti-peeping control signal.

[0051] In this embodiment, by connecting the input ends of the second active switches T2 corresponding to the plurality of anti-peeping light-emitting units 114 to the same anti-peeping control signal control, the brightness of the anti-peeping light-emitting units 114 is made consistent and the wiring is simpler.

[0052] In a specific embodiment, the voltage of the anti-peeping control signal can be controlled according to the brightness (grayscale) of the current display panel 100. For example, the average grayscale of the current display panel 100 is calculated, and when the average grayscale is in different grayscale ranges, the anti-peeping control signal has different voltages. The specific relationship can be proportional or exponential. For example, in order to simplify the calculation, it can be calculated whether the grayscale of more than half of the sub-pixels of the current display panel 100 is greater than a certain set value. When it is greater than, it is determined to be a high grayscale display screen, and when it is less than, it is determined to be a low grayscale display screen. When the high grayscale display screen is displayed, the anti-peeping light-emitting unit 114 is controlled to emit a brighter anti-peeping light, and when the low grayscale display screen is displayed, the anti-peeping light-emitting unit 114 is controlled to emit a darker anti-peeping light.

[0053] Figure 4 is a timing diagram of the pixel driving circuit of the first embodiment of the present application, see Figure 4As shown, the pixel driving circuit 110 further includes a first control signal Scan1, a second control signal Scan2 and a third control signal Scan3, the first control signal Scan1 is connected to the control end of the fourth active switch T4, the second control signal Scan2 is connected to the control end of the fifth active switch T5, and the third control signal Scan3 is connected to the control end of the third active switch T3; the pixel driving circuit 110 includes a reset period, a write period and a display period, in the reset period, the third control signal Scan3 is at a conduction level, the third active switch T3 is turned on, and the second node N2 is reset; in the write period, the second control signal Scan2 and the first control signal Scan1 are respectively at a conduction level, the fifth active switch T5 and the fourth active switch T4 are turned on, the first node N1 inputs the compensated data signal Data, and the control end of the second active switch T2 is turned on after receiving the compensated data signal Data of the first node N1; in the display period, the first active switch T1 is turned on, and the display light-emitting unit 112 emits light; under the control of the anti-peeping control signal, the anti-peeping light-emitting unit 114 emits light.

[0054] In this embodiment, the compensation performed by the external compensation circuit for the data signal Data is generally performed before the factory to detect the display sub-pixel 132, and then the compensation data corresponding to each display sub-pixel 132 is calculated. When the display panel 100 is displaying, the third active switch T3 mainly resets the second node N2 so that the potential of the first node N1 is at a preset potential. When the second control signal Scan2 and the third control signal Scan3 are at the on level, the potential of the first node N1 is raised to the potential of the compensated data signal Data, and the first capacitor C1 is charged at the same time. During the display period, the display light-emitting unit 112 is controlled to emit light through the power supply voltage signal at the input end of the first capacitor C1 and the first active switch T1, and the anti-peeping control signal at the input end of the second active switch T2 controls the anti-peeping light-emitting unit 114 to emit light. Of course, the power supply voltage signal can also be connected to the input end of the second active switch T2, thereby saving the routing of the anti-peeping control signal, but there is a problem that the potential of the anti-peeping control signal cannot be adjusted.

[0055] It can be understood that the conduction level is a level that can make the active switch in a conduction state when applied to the control terminal of the active switch. For example, when the active switch is an N-type thin film transistor, the conduction level is a logic high level, and when the active switch is a P-type thin film transistor, the conduction level is a logic low level.

[0056] Figure 5 is a schematic diagram of a pixel driving circuit of a second embodiment of the present application, Figure 6is a timing diagram of the pixel driving circuit of the second embodiment of the present application, see Figures 5 and 6 As shown, the pixel driving circuit 110 includes a first control signal Scan1 and a second control signal Scan2, the first control signal Scan1 is connected to the control end of the fourth active switch T4 and the control end of the fifth active switch T5, respectively, and the second control signal Scan2 is connected to the control end of the third active switch T3; the pixel driving circuit 110 includes a reset period, a write period and a display period, in the reset period, the second control signal Scan2 is at a conduction level, the third active switch T3 is turned on, and the second node N2 is reset; in the write period, the first control signal Scan1 is at a conduction level, the fifth active switch T5 and the fourth active switch T4 are turned on, the first node N1 inputs the compensated data signal Data, and the control end of the second active switch T2 is turned on after receiving the compensated data signal Data of the first node N1; in the display period, the first active switch T1 is turned on, and the display light-emitting unit 112 emits light; under the control of the anti-peeping control signal, the anti-peeping light-emitting unit 114 emits light. Wherein, data is a data signal Data, and Vsen is a reset signal Vsen input by an external compensation circuit to control the second node N2 to be at a preset potential.

[0057] In this embodiment, by controlling the fourth active switch T4 and the fifth active switch T5 at the same time, when the data signal Data is input, the first capacitor C1 can be charged, and the fifth active switch T5 can be turned on, and the anti-peeping light-emitting unit 114 can be controlled by controlling the presence or absence of the anti-peeping control signal. Compared with the previous embodiment, the number of control signals can be reduced, thereby reducing the complexity of routing.

[0058] Figure 7 is a schematic diagram of a pixel driving circuit according to a third embodiment of the present application, Figure 8 is a timing diagram of a pixel driving circuit of the third embodiment of the present application, see Figures 7 and 8As shown, the pixel driving circuit 110 includes a first control signal Scan1, and the anti-peeping driving circuit 113 also includes a second capacitor C2, one end of the second capacitor C2 is connected to the control end of the second active switch T2, and the other end of the second capacitor C2 is connected to the output end of the second active switch T2; the first control signal Scan1 is respectively connected to the control end of the third active switch T3, the control end of the fourth active switch T4, and the control end of the fifth active switch T5; the pixel driving circuit 110 includes a reset writing period and a display period, in which the first control signal Scan1 is at a conduction level, the third active switch T3, the fourth active switch T4, and the fifth active switch T5 are turned on, and after a delay of a preset time, the compensated data signal Data is written from the first node N1; in the display period, the first active switch T1 and the second active switch T2 are respectively turned on, and the display light-emitting unit 112 and the anti-peeping light-emitting unit 114 emit light respectively.

[0059] In this embodiment, the control signal is further reduced to one control line, and the third active switch T3, the fourth active switch T4 and the fifth active switch T5 are controlled by the first control signal Scan1. Of course, in order to avoid the conflict between the reset of the first node N1 and the input of the data signal Data, the data signal Data can be input after a preset time delay, and the data signal Data is input after the second node N2 is reset. For the anti-peeping control signal, it is at a preset potential during the display period, and the anti-peeping light-emitting unit 114 is controlled to emit light. At this time, the first control signal Scan1, the reset signal Vsen and the data signal Data are all in a low level state. The first active switch T1 and the second active switch T2 are kept turned on by the first capacitor C1 and the second capacitor C2, so that the display light-emitting unit 112 and the anti-peeping light-emitting unit 114 can emit light together.

[0060] The function of the second capacitor C2 is consistent with that of the first capacitor C1. In the data signal Data writing period, the first capacitor C1 and the second capacitor C2 are charged by the data signal Data to maintain the on state of the first active switch T1 and the second active switch T2 in the display period.

[0061] Of course, in another embodiment, the fourth active switch T4 may be removed by directly passing the data signal Data to the second capacitor C2 or turning on the second active switch T2 during the writing period. In other words, by directly connecting the second active switch T2 of the anti-peeping driving circuit 113 to the first node N1, the fourth active switch T4 is not required.

[0062] Fig. 9is a schematic diagram of a pixel driving circuit according to a fourth embodiment of the present application, Fig.10 is a timing diagram of a pixel driving circuit of the fourth embodiment of the present application, see Figures 9 and 10 As shown, on the basis of the second embodiment, the fourth active switch T4 is saved. The pixel driving circuit 110 includes a reset period, a write period and a display period. The reset period is consistent with the above. During the write period, the data signal Data is input to the first node N1, which not only charges the first capacitor C1, but also charges the second capacitor C2, so that the anti-peeping light-emitting unit 114 can emit light during the display period.

[0063] Fig.11 is a schematic diagram of the display device of the present application, see Fig.11 As shown, the present application also discloses a display device, the display device 200 includes a driving circuit board 210 and a display panel 100 in any of the above embodiments, wherein the driving circuit board 210 is used to drive the display panel 100 to display. The driving circuit board 210 is different from the above pixel driving circuit 110 in that the driving circuit board is arranged outside the base substrate 121, needs to be connected by binding, and is generally used to provide voltage and control signals, etc. to the pixel driving circuit 110.

[0064] It should be noted that the inventive concept of the present application can form a large number of embodiments, but the length of the application document is limited and it is impossible to list them one by one. Therefore, under the premise of no conflict, the embodiments or technical features described above can be arbitrarily combined to form new embodiments. After the embodiments or technical features are combined, the original technical effects will be enhanced.

[0065] The above content is a further detailed description of the present application in combination with specific optional implementation methods, and it cannot be determined that the specific implementation of the present application is limited to these descriptions. For ordinary technicians in the technical field to which the present application belongs, several simple deductions or substitutions can be made without departing from the concept of the present application, which should be deemed to fall within the scope of protection of the present application.

Claims

1. A pixel driving circuit, characterized in that: Each pixel area includes a display driving circuit, a display light-emitting unit, an anti-peeping driving circuit and an anti-peeping light-emitting unit; The display driving circuit includes a first active switch and a first node, and the anti-peeping driving circuit includes a second active switch. The control ends of the first active switch and the second active switch are respectively connected to the first node. The first node is used to receive a data signal. The first node is used to control the first active switch to drive the display light-emitting unit to emit light, and control the second active switch to drive the anti-peeping light-emitting unit to emit light; the anti-peeping light-emitting unit and the display light-emitting unit are controlled to emit light under the same data signal.

2. The display panel according to claim 1, characterized in that: The display driving circuit further includes a third active switch and a first capacitor, wherein an input end of the third active switch is externally connected to an external compensation circuit, an output end of the third active switch is connected to a second node, one end of the display light emitting unit is connected to the second node, and an output end of the first active switch is connected to the second node; one end of the first capacitor is connected to the first node, and the other end of the first capacitor is connected to the second node; The external compensation circuit is used to detect the voltage of the second node through the third active switch and compensate the input data signal of the first node; The anti-peeping light-emitting unit operates under the drive of the compensated data signal of the first node.

3. The display panel according to claim 2, characterized in that: The anti-peeping driving circuit further includes a fourth active switch, wherein an input end of the fourth active switch is connected to the first node, and an output end of the fourth active switch is connected to a control end of the second active switch; The fourth active switch is used to control the conduction or disconnection between the first node and the control end of the second active switch; The display driving circuit further includes a fifth active switch, wherein an output end of the fifth active switch is connected to the first node, and an input end of the fifth active switch is connected to the data signal; The input end of the second active switch is connected to an anti-peeping control signal, and the input end of the first active switch is connected to a power supply voltage signal.

4. The display panel according to claim 3, characterized in that: Input ends of the plurality of second active switches are respectively connected to the same anti-peeping control signal.

5. The display panel according to claim 3, characterized in that: The pixel driving circuit further includes a first control signal, a second control signal and a third control signal. The first control signal is connected to the control end of the fourth active switch, the second control signal is connected to the control end of the fifth active switch, and the third control signal is connected to the control end of the third active switch; The pixel driving circuit includes a reset period, a writing period and a display period. During the reset period, the third control signal is at a conduction level, the third active switch is turned on, and the second node is reset; During the writing period, the second control signal and the first control signal are at the on level respectively, the fifth active switch and the fourth active switch are turned on, the first node inputs the compensated data signal, and the control end of the second active switch is turned on after receiving the compensated data signal of the first node; During the display period, the first active switch is turned on, and the display light-emitting unit emits light; Under the control of the anti-peeping control signal, the anti-peeping light-emitting unit emits light.

6. The display panel according to claim 3, characterized in that: The pixel driving circuit includes a first control signal and a second control signal, and the anti-peeping driving circuit also includes a second capacitor, one end of the second capacitor is connected to the control end of the second active switch, and the other end of the second capacitor is connected to the output end of the second active switch; The first control signal is connected to the control end of the fourth active switch and the control end of the fifth active switch respectively, and the second control signal is connected to the control end of the third active switch; The pixel driving circuit includes a reset period, a writing period and a display period. During the reset period, the second control signal is at a conduction level, the third active switch is turned on, and the second node is reset; During the writing period, the first control signal is at a conduction level, the fifth active switch and the fourth active switch are turned on, the first node inputs the compensated data signal, and the control end of the second active switch is turned on after receiving the compensated data signal of the first node; During the display period, the first active switch is turned on, and the display light-emitting unit emits light; Under the control of the anti-peeping control signal, the anti-peeping light-emitting unit emits light.

7. The display panel according to claim 3, characterized in that: The pixel driving circuit includes a first control signal, the anti-peeping driving circuit also includes a second capacitor, one end of the second capacitor is connected to the control end of the second active switch, and the other end of the second capacitor is connected to the output end of the second active switch; The first control signal is respectively connected to the control end of the third active switch, the control end of the fourth active switch and the control end of the fifth active switch; The pixel driving circuit includes a reset writing period and a display period. During the reset writing period, the first control signal is at an on level, the third active switch, the fourth active switch and the fifth active switch are turned on, and after a delay of a preset time, a compensated data signal is written from the first node; During the display period, the first active switch and the second active switch are respectively turned on, and the display light-emitting unit and the anti-peeping light-emitting unit are respectively illuminated.

8. A display panel, characterized in that: The display panel comprises a base substrate and a pixel driving circuit according to any one of claims 1 to 7, wherein the pixel driving circuit layer is arranged on the base substrate, and the display panel further comprises: a light-emitting unit layer, disposed on the pixel driving circuit layer, and comprising a plurality of display light-emitting units and a plurality of anti-peeping light-emitting units; and The light-shielding layer is arranged on the light-emitting unit layer and includes a plurality of light-shielding parts, and the light-shielding parts are arranged corresponding to the anti-peeping light-emitting units.

9. The display panel according to claim 8, characterized in that: At least one display light emitting unit and one anti-peeping light emitting unit are arranged in the same pixel area, and the anti-peeping light emitting unit and the display light emitting unit have different light emitting colors.

10. A display device, characterized in that: It comprises a driving circuit board and a display panel as claimed in any one of claims 8 to 9, wherein the driving circuit board is used to provide a data signal to the pixel driving circuit to drive the display panel to display.

Images