Light detection structure, display panel and display device

Abstract

The invention relates to a light detection structure, a display panel and a display device. The light detection structure comprises a test circuit, a reference circuit and a signal processing module. The test circuit comprises a photosensitive transistor unit and an auxiliary transistor unit which are connected in series; the reference circuit comprises a reference transistor unit; the equivalent resistance values of the photosensitive transistor unit, the auxiliary transistor unit and the reference transistor unit are the same; the control end of the test circuit is connected with the control end of the reference circuit, and the signal input end of the test circuit is connected with the signal input end of the reference circuit; the signal processing module comprises a first input end and a second input end, and the first input end is electrically connected to the signal output end of the photosensitive transistor unit; the second input end is electrically connected to the signal output end of the reference transistor unit. According to the arrangement, the auxiliary transistor unit and the reference transistor unit which have the same equivalent resistance as the photosensitive transistor unit are arranged, so that the signal obtained by the signal processing module is not influenced by the process, and the stability is improved.

Description

Light detection structure, display panel and display device

[0001] The present invention relates to, but is not limited to, the field of display technology, and in particular to a light detection structure, a display panel and a display device.

[0002] With the widespread application of LCD (Liquid Crystal Display) display panels, more and more electronic devices using LCD display panels are equipped with light sensors (also called light sensors) to adjust the brightness of the LCD display panel according to the light brightness of the environment in which the electronic device is located, thereby saving power consumption and providing users with a better visual experience.

[0003] However, due to the problem of photoelectric curve characteristic drift of the light sensor, there is a large error in the detection accuracy.

[0004]

[0005] The purpose of the present application is to provide a light detection structure, a display panel and a display device, which can improve detection accuracy.

[0006] According to a first aspect of an embodiment of the present application, a light detection structure is provided, the light detection structure comprising:

[0007] A test circuit, comprising a photosensitive transistor unit and an auxiliary transistor unit connected in series, wherein the photosensitive transistor unit is used to receive an ambient light signal, and the auxiliary transistor unit is light-proof; when the light conditions of the photosensitive transistor unit and the auxiliary transistor unit are the same, the equivalent resistance values ​​of the two are the same; the control end of the photosensitive transistor unit is connected to the control end of the auxiliary transistor unit; a reference circuit, wherein the signal input end of the reference circuit is connected to the signal input end of the test circuit;

[0008] The signal processing module comprises a first input terminal and a second input terminal, and the signal processing module is used to compare the signals of the first input terminal and the second input terminal; the first input terminal is electrically connected to the signal output terminal of the photosensitive transistor unit; and the second input terminal is electrically connected to the reference circuit.

[0009] Furthermore, the test circuit and the reference circuit are commonly connected to a data terminal, and the electrical signal obtained by the second input terminal of the signal processing module is the electrical signal output by the data terminal.

[0010] The reference circuit includes a reference transistor unit, and the reference transistor unit is protected from light;

[0011] When the light conditions of the photosensitive transistor unit, the auxiliary transistor unit and the reference transistor unit are the same, the equivalent resistance values ​​of the three are the same; and the control end of the test circuit is connected to the control end of the reference circuit.

[0012] Furthermore, the number of the reference transistor units is multiple, and the multiple reference transistor units are connected in series; and the number of the reference transistors is the same as the sum of the number of the photosensitive transistor units and the auxiliary transistor units in the test transistor;

[0013] The number of transistor units between the first input terminal and the control terminal of the test circuit is the same as the number of transistor units between the second input terminal and the control terminal of the reference circuit.

[0014] Further, the number of the reference transistors is different from the sum of the number of the photosensitive transistor units and the auxiliary transistor units in the test transistor;

[0015] The number of transistor units between the first input terminal and the control terminal of the test circuit is the same as or different from the number of transistor units between the second input terminal and the control terminal of the reference circuit.

[0016] Furthermore, there are multiple auxiliary transistor units, and a photosensitive transistor unit and an auxiliary transistor unit are provided between the first input end and the control end of the test circuit, or only a photosensitive transistor unit is provided between the first input end and the control end of the test circuit.

[0017] Furthermore, the signal processing module includes an operational amplifier.

[0018] Furthermore, the minimum distance between the photosensitive transistor unit and an adjacent auxiliary transistor unit is less than or equal to 10 mm; and / or the minimum distance between the test circuit and the reference circuit is less than or equal to 10 mm.

[0019] According to a second aspect of an embodiment of the present application, a display panel is provided, comprising a light detection structure.

[0020] Further, the display panel includes a display area and a non-display area, the display panel also includes a drive control layer, the light detection structure is arranged on the drive control layer and is located in the non-display area; and / or,

[0021] The display panel includes an outer light-shielding layer, which is arranged above the light detection structure. In addition, a through light-transmitting hole is opened on the outer light-shielding layer, and the orthographic projection of the photosensitive transistor unit on the outer light-shielding layer falls into the light-transmitting hole.

[0022] Furthermore, the display panel also includes a backlight source assembly and a color filter, and the color filter is arranged on a side of the photosensitive transistor unit away from the backlight source assembly.

[0023] Furthermore, there are multiple light detection structures, and the color filter is disposed on the photosensitive transistor unit in each light detection structure;

[0024] The colors of the color filters on at least two of the light detection structures are different.

[0025] According to a third aspect of an embodiment of the present application, a display device is provided, comprising a display panel.

[0026] The beneficial technical effects brought about by the technical solution provided by the embodiment of the present application are:

[0027] In the present application, an auxiliary transistor unit and a reference transistor unit having the same equivalent resistance as the photosensitive transistor unit are provided so that the signal obtained by the signal processing module is not affected by the process, thereby increasing the stability of the signal.

[0028] In order to more clearly illustrate the technical solutions in the embodiments of the present disclosure, the drawings required for use in the description of the embodiments will be briefly received below. Obviously, the drawings described below are only some embodiments of the present disclosure. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0029] FIG. 1 is a circuit diagram of a light detection structure.

[0030] FIG. 2 is a photoelectric curve diagram of a display panel.

[0031] FIG. 3 is a photoelectric curve diagram of multiple display panels.

[0032] FIG. 4 is a circuit diagram of a light detection structure according to an embodiment of the present invention.

[0033] FIG. 5 is a circuit diagram of a light detection structure according to another embodiment of the present invention.

[0034] FIG. 6 is a circuit diagram of a light detection structure according to yet another embodiment of the present invention.

[0035] FIG. 7 is a circuit diagram of a light detection structure according to yet another embodiment of the present invention.

[0036] FIG. 8 is a circuit diagram of a light detection structure according to yet another embodiment of the present invention.

[0037] FIG. 9 is a schematic structural diagram of a display panel according to an embodiment of the present invention.

[0038] FIG. 10 is a circuit diagram of a light detection structure according to yet another embodiment of the present invention.

[0039] Description of Reference Numerals Display panel 10 Display area 11 Non-display area 12 Light detection structure 20 Test circuit 100 Photosensitive transistor unit 110 Auxiliary transistor unit 120 Reference circuit 200 Reference transistor unit 210 Signal processing module 400 Operational amplifier 410 First input terminal 411 Second input terminal 412 Signal output terminal 413 Digital-to-analog converter 420 Data terminal 500 Drive control terminal 600 First signal line 710 Second signal line 720

[0040] Exemplary embodiments will be described in detail herein, examples of which are shown in the accompanying drawings. When the following description refers to the drawings, the same numbers in different drawings represent the same or similar elements unless otherwise indicated. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with the present invention. Instead, they are merely examples of devices and methods consistent with some aspects of the present invention as detailed in the appended claims.

[0041] The terms used in this application are only for the purpose of describing specific embodiments and are not intended to limit this application. Unless otherwise defined, the technical terms or scientific terms used in this application should be understood by people with ordinary skills in the field to which the present invention belongs. The words "one" or "one" and the like used in this application specification and claims do not indicate a quantitative limitation, but indicate the existence of at least one. "Multiple" means two or more. "Including" or "including" and the like mean that the elements or objects appearing in front of "including" or "including" include the elements or objects listed after "including" or "including" and their equivalents, and do not exclude other elements or objects. "Connected" or "connected" and the like are not limited to physical or mechanical connections, and can include electrical connections, whether direct or indirect. "On" and / or "below" and the like are only for the convenience of explanation, and are not limited to a position or a spatial orientation. The singular forms of "one", "said" and "the" used in this application specification and the attached claims are also intended to include plural forms, unless the context clearly indicates other meanings. It should also be understood that the term "and / or" used herein refers to and encompasses any and all possible combinations of one or more of the associated listed items.

[0042] The present application discloses a display device, which includes a display panel. The display panel includes a backlight assembly, a drive control layer, a first electrode layer, a liquid crystal deflection module, a second electrode layer and a filter from bottom to top. The backlight assembly emits light in the direction pointing to the filter. The drive control layer is electrically connected to the first electrode layer to control the potential difference between the first electrode layer and the second electrode layer, that is, to control the potential difference applied to the liquid crystal deflection module, thereby controlling the deflection direction of the liquid crystal in the liquid crystal deflection module, and then whether the light emitted by the backlight assembly can pass through the liquid crystal deflection module to reach the filter and be emitted outward to be captured by the user.

[0043] The display panel can be applied to display devices such as mobile phones, computers, tablets, and smart watches.

[0044] In order to reduce power consumption, increase standby time and protect eyes, existing display devices are equipped with a light detection structure for detecting ambient light. The brightness or color temperature of the ambient light source is detected through the light detection structure, and the detected brightness or color temperature is transmitted to the processor. After the processor determines the brightness and color temperature of the ambient light, the brightness and color temperature of the display device are readjusted and output, that is, the potential difference on both sides of the liquid crystal deflection module is readjusted. For example, when the brightness of the ambient light is brighter, the user's pupil is less open, and less light enters the human eye. At this time, the brightness of the display panel needs to be increased so that the user can see the content displayed on the display panel clearly. When the brightness of the ambient light is darker, the user's pupil is more open, and more light enters the human eye. At this time, the brightness of the display panel needs to be lowered to avoid damage to the eyes due to excessive light entering the human eye.

[0045] As shown in FIG. 1 , in one design, the light detection structure includes a photosensitive transistor unit 1 , a reference transistor unit 2 , and a signal processing module 3 .

[0046] The control terminals of the photosensitive transistor unit 1 and the reference transistor unit 2 are connected to receive the same driving signal VGS. The signal input terminals of the photosensitive transistor unit 1 and the reference circuit 2 are connected to receive the same data signal VDD. The signal processing module 3 includes a first input terminal and a second input terminal, which are respectively connected to the signal output terminals of the photosensitive transistor unit 1 and the reference circuit 2. The voltage of the first input terminal is taken as V1, and the voltage of the second input terminal is taken as V2. Among them, the photosensitive transistor unit 1 is used to receive the ambient light signal, and the reference transistor unit 2 is light-proof.

[0047] When the photosensitive transistor unit 1 and the reference transistor unit 2 are given a driving signal VG and a data signal VD at the same time, the current (IDS) of the photosensitive transistor unit 1 and the reference transistor unit 2 is calculated as follows:

[0048] Among them, μFE represents the carrier mobility determined by the electric field effect, and its value is affected by temperature and light conditions. Cox represents the capacitance per unit area of ​​the gate oxide film, and its value is relatively fixed for the same transistor. W / L represents the channel width / channel length, and its value is relatively fixed for the same transistor.

[0049] Since the equivalent resistance R of the photosensitive transistor unit 1 and the reference transistor unit 2 is the same, it means that the Cox and W / L of the two are the same. And the two are close to each other, and the temperature of the environment in which they are located can be considered to be the same. At this time, the difference in IDS between the two is affected by the lighting conditions. Correspondingly, V1 = IDS1×R, V1 = IDS2×R.

[0050] When the photosensitive transistor unit 1 is not illuminated, the IDS corresponding to the photosensitive transistor unit 1 and the reference transistor unit 2 are the same, that is, IDS1=IDS2, and V1=V2.

[0051] When the photosensitive transistor unit 2 is illuminated, IDS1 on the photosensitive transistor unit 1 is greater than IDS2 on the reference transistor unit 2, that is, IDS1 is greater than IDS2, then V1 = IDS1×R>V2 = IDS2×R.

[0052] When the signal processing module 3 includes an operational amplifier and a digital-to-analog converter, the signal output terminal of the operational amplifier is electrically connected to the signal input terminal of the analog-to-digital converter (ADC). The electrical signal output by the operational amplifier is A×(V1-V2)=A×R(ISD1-ISD2). Where A is the gain of the operational amplifier 410.

[0053] The curve of the ambient illumination and the ADC acquisition value obtained by the above method is shown in Figure 2. The controller is electrically connected to the signal processing module to receive the sampling value sent by the digital-to-analog converter, and controls the driving control layer to apply different voltages to the liquid crystal deflection layer according to the sampling value to adjust the display panel to display different brightness.

[0054] However, the inventors have found through experiments that the three factors of μFE, Cox and W / L are affected by process drift, resulting in large differences in the IDS values ​​of the same transistors in different display panels 10. The inventors tested three different display panels 10, and the collected curves of ambient illumination and ADC collection values ​​are shown in Figure 3. Therefore, this will result in the need to adjust the photoelectric curve of each display panel 10 before shipment, and after shipment, it is impossible to guarantee the drift of the photoelectric curve caused by changes in ambient temperature.

[0055] In order to solve the above problems, the inventors have made some improvements:

[0056] Specifically, as shown in FIG. 4 and FIG. 5 , the light detection structure 20 includes a test circuit 100 , a reference circuit 200 and a signal processing module 400 .

[0057] Among them, the test circuit 100 includes a photosensitive transistor unit 110 and an auxiliary transistor unit 120 connected in series. The photosensitive transistor unit 110 is used to receive ambient light signals, and the auxiliary transistor unit 120 is protected from light. When the lighting conditions of the photosensitive transistor unit 110 and the auxiliary transistor unit 120 are the same, the equivalent resistance values ​​of the two are the same. The control end of the photosensitive transistor unit 110 and the control end of the auxiliary transistor unit 120 are connected, that is, the control ends (gates) of the photosensitive transistor unit 110 and the auxiliary transistor unit 120 are commonly connected to the same driving control end 600 to synchronously obtain the driving signal VGS and realize synchronous opening or closing. The photosensitive transistor unit 110 and the auxiliary transistor unit 120 are connected in series and connected to the data end 500 to obtain the data signal VDD.

[0058] The signal processing module 400 includes a first input terminal 411 and a second input terminal 412, and is used to compare signals of the first input terminal 411 and the second input terminal 412. The first input terminal 411 is electrically connected to the signal output terminal 413 of the photosensitive transistor unit 110. The second input terminal 412 is electrically connected to the reference circuit 200.

[0059] Taking the embodiment shown in FIG. 4 as an example, the light sensing transistor unit 110 includes a light sensing transistor unit 110 (hereinafter referred to as M1 ) and an auxiliary transistor unit 120 (hereinafter referred to as M2 ) connected in series.

[0060] Assume that the equivalent resistance of M1 is Roff1, the equivalent resistance of M2 is Roff2, and the equivalent resistance of M3 is Roff3. The voltage at the end where the first signal line 710 contacts the test circuit 100 (i.e., the position between M1 and M2) is taken as V1, that is, the voltage received by the first input terminal 411 of the signal processing module 400 is V1.

[0061] When M1 is not illuminated, the IDS of M1 and M2 are the same. (Roff is the equivalent resistance of the transistor unit), then Roff1 = Roff2. In other words, when the data terminal 500 outputs the voltage VDD, the relationship between V1 and V2 is as follows:

[0062] V2=mVDD (the data of m depends on the specific structure of the reference circuit 200, which will be explained in detail below).

[0063] When M1 is illuminated, the ISD1 leakage current corresponding to M1 will increase, and the mobility of μFE carriers will increase. When the data terminal 500 outputs the voltage VDD, due to the IDS and (Roff is the equivalent resistance of the transistor unit). At this time, the relationship between the equivalent resistance Roff1 of M1 and the equivalent resistance Roff2 of M2 is as follows: V1=VDD×Roff2 / (Roff1+Roff2)=VDD×μFE1 / (μFE1+μFE2);

[0064] According to the above derived formula, by adding an auxiliary transistor unit 120 with the same equivalent resistance as the photosensitive transistor unit 110 under the same lighting conditions to the light detection structure 20, the parameters affecting the value of V1 will be simplified so that it is only affected by the μFE carrier mobility, and the process factors on the same display panel 10 will be eliminated, so that the input voltage signal and the output voltage signal obtained by the signal processing module 400 are only related to the μFE carrier mobility after illumination and the controllable VDD, thereby avoiding unexpected drift of the photoelectric curves of different display panels 10 and avoiding the problem of unexpected drift of the photoelectric curve caused by changes in ambient temperature when the display panel 10 is in use at one end.

[0065] Specifically, as shown in FIG5 , the reference circuit 200 may not include any components. In this case, the test circuit 100 and the reference circuit 200 are connected to the data terminal 500. The electrical signal obtained by the second input terminal 412 of the signal processing module 400 is the electrical signal output by the data terminal 500. In other words, the voltage of V2 is always VDD. When M1 is not illuminated:

[0066] V2 = VDD (at this time, the m mentioned above is 1);

[0067] When M1 shines light;

[0068] V1=VDD×Roff2 / (Roff1+Roff2)=VDD×μFE1 / (μFE1+μFE2), V2=VDD;

[0069] As shown in combination with FIG. 4 and FIG. 6 , the reference circuit 200 includes a reference transistor unit 210. The equivalent resistance of the photosensitive transistor unit 110, the auxiliary transistor unit 120 and the reference transistor unit 210 is the same. It should be noted that the same resistance referred to here means that when the light conditions of the photosensitive transistor unit 110, the auxiliary transistor unit 120 and the reference transistor unit 210 are consistent, the equivalent resistance of the three is the same. In other words, when the light conditions of the three are consistent, the corresponding values ​​of the three factors μFE, Cox and W / L are the same. At the same time, the control end of the test circuit 100 is connected to the control end of the reference circuit 200, that is, the control ends of the photosensitive transistor unit 110, the auxiliary transistor unit 120 in the test circuit 100, and the reference transistor unit 210 in the reference circuit 200 are connected to the same data end 500 to synchronously obtain the drive signal VGS. The signal input terminal of the test circuit 100 is connected to the signal input terminal of the reference circuit 200 and is also connected to the driving control terminal 600 to synchronously obtain the same data signal VDD and realize synchronous opening and closing.

[0070] The first input terminal 411 of the signal processing module 400 is electrically connected to the signal output terminal 413 of the photosensitive transistor unit 110 through the first signal line 710, that is, directly (refer to FIG. 4) or indirectly (refer to FIG. 6) connected between the photosensitive transistor unit 110 and the auxiliary transistor unit 120. In other words, one end of the first signal line 710 is directly or indirectly electrically connected between the signal output terminal 413 of the photosensitive transistor unit 110 and the auxiliary transistor unit 120, and the other end is connected to the first input terminal 411 of the signal processing module 400. The second input terminal 412 of the signal processing module 400 is electrically connected to the signal output terminal 413 of the reference transistor unit 210 through the second signal line 720. In other words, one end of the second signal line 720 is electrically connected to the signal output terminal 413 of the reference transistor unit 210, and the other end is connected to the second input terminal 412 of the signal processing module 400.

[0071] By providing the auxiliary transistor unit 120 and the reference transistor unit 210 with the same equivalent resistance as the photosensitive transistor unit 110, the signal obtained by the signal processing module 400 can also be free from the influence of the manufacturing process, thereby increasing the stability of the signal.

[0072] 4, the photosensitive transistor unit 110 includes a photosensitive transistor unit 110 (hereinafter referred to as M1) and an auxiliary transistor unit 120 (hereinafter referred to as M2) connected in series. The auxiliary transistor unit 120 includes two reference transistor units 210 (hereinafter referred to as M3 and M4, respectively) connected in series.

[0073] Assume that the equivalent resistance of M1 is Roff1, the equivalent resistance of M2 is Roff2, and the equivalent resistance of M3 is Roff3. The voltage at the end of the first signal line 710 that contacts the test circuit 100 (i.e., the position between M1 and M2) is taken as V1, that is, the voltage received by the first input terminal 411 of the signal processing module 400 is V1. The voltage at the end of the second signal line 720 that contacts the reference circuit 200 (and the position between M3 and M4) is taken as V2, that is, the voltage received by the second input terminal 412 of the signal processing module 400 is V2.

[0074] As mentioned above, when M1 is not illuminated, the relationship between V1 and V2 is as follows:

[0075] (At this time, the m mentioned above is ).

[0076] In this embodiment, the signal processing module 400 includes an operational amplifier 410 , and the operational amplifier 410 further includes a signal output terminal 413 . At this time, the voltage U0 outputted by the signal output terminal 413 is 0.

[0077] As mentioned above, when M1 is illuminated, V1 = VDD × Roff2 / (Roff1 + Roff2) = VDD × μFE1 / (μFE1 + μFE2);

[0078] After being processed by the operational amplifier 410, the voltage outputted by the signal output terminal 413 is:

[0079] According to the above derived formula, by adding an auxiliary transistor unit 120 with the same equivalent resistance as the photosensitive transistor unit 110 under the same lighting conditions to the light detection structure 20, the process factor on the same display panel 10 can be eliminated, so that the input voltage signal and the output voltage signal obtained by the signal processing module 400 are only related to the μFE carrier mobility after illumination and the controllable VDD, thereby avoiding unexpected drift of the photoelectric curves of different display panels 10 and avoiding unexpected drift of the photoelectric curve caused by changes in ambient temperature when the display panel 10 is in use.

[0080] It should be noted that the “when M1 is not illuminated” mentioned above should be understood as “when the light signal received by the photosensitive transistor unit 110 is less than or equal to the threshold value”, and the voltage signal on the first input terminal 411 is equal to the voltage signal on the second input terminal 412. “When M1 is illuminated” should be understood as “when the light signal received by the photosensitive transistor unit 110 is greater than the threshold value”, and the voltage signal on the first input terminal 411 is greater than the voltage signal on the second input terminal 412. The threshold value can be determined according to the actual situation, and the corresponding transistor unit can be selected or debugged according to the determined value.

[0081] In the above configuration, the number of reference transistor units 210 is multiple, and multiple reference transistor units 210 are connected in series. In addition, the number of reference transistors is the same as the sum of the number of photosensitive transistor units 110 and auxiliary transistor units 120 in the test transistor. The number of transistor units between the first input terminal 411 and the control terminal of the test circuit 100 is the same as the number of transistor units between the second input terminal 412 and the control terminal of the reference circuit 200. In this embodiment, by limiting the number of transistor units and limiting the connection positions of the first signal line 710 and the second signal line 720, when M1 is not illuminated, V1=V2, and the voltage U0 output by the operational amplifier 410=0. This facilitates the drawing and comparison of photoelectric curves.

[0082] In the embodiment corresponding to FIG. 4 , the number of transistor units between the first input terminal 411 and the control terminal of the test circuit 100 is the same as the number of transistor units between the second input terminal 412 and the control terminal of the reference circuit 200 .

[0083] Of course, in other embodiments, the number of transistor units between the first input terminal 411 and the control terminal of the test circuit 100 and the number of transistor units between the second input terminal 412 and the control terminal of the reference circuit 200 may be different.

[0084] As shown in Fig. 7 and Fig. 8, the number of transistor units in the test circuit 100 is 2, namely, one photosensitive transistor unit 110 and one auxiliary transistor unit 120. The number of reference transistor units 210 in the reference circuit 200 is 3.

[0085] At this time, if the connection relationship between the first signal line 710 and the second signal line 720 is as shown in FIG7. When M1 is not illuminated,

[0086] (At this time, the m mentioned above is ),

[0087] When M1 is illuminated,

[0088] V1=VDD×μFE1 / (μFE1+μFE2),

[0089] At this time, if the connection relationship between the first signal line 710 and the second signal line 720 is as shown in FIG8. When M1 is not illuminated,

[0090] (At this time, the m mentioned above is ),

[0091] When M1 is illuminated,

[0092] V1=VDD×μFE1 / (μFE1+μFE2),

[0093] By analogy, the number of reference transistor units 210 in the reference circuit 200 is 4, 5 or more than 6.

[0094] Similarly, in the embodiment corresponding to FIG. 4 , only the auxiliary transistor unit 120 is disposed between the first input terminal 411 and the control terminal of the test circuit 100 .

[0095] Of course, in other embodiments, the number of auxiliary transistor units 120 may be multiple, and not only the photosensitive transistor unit 110 but also the auxiliary transistor unit 120 are provided between the first input terminal 411 and the control terminal of the test circuit 100. As shown in FIG6 , when M1 is not illuminated, When M1 is illuminated, V1 = VDD×μFE1 / (μFE1+μFE2+μFE3).

[0096] The inventors have found through a large number of experiments that μFE is not only affected by the lighting conditions, but also by the temperature. In order to reduce the impact of temperature on the μFE of different transistor units and improve the accuracy of detecting lighting conditions. The inventors have also conducted the following research. The inventors found that when the minimum distance between the photosensitive transistor unit 110 and the adjacent auxiliary transistor unit 120 is less than or equal to 10 mm, the temperature of the environment in which the photosensitive transistor unit 110 and the adjacent auxiliary transistor unit 120 are located can be guaranteed to a large extent. Even if the temperature affects μFE, the ratio of V1 will not be greatly affected, thereby ensuring the accuracy of the detection. If a reference transistor unit 210 is provided in the reference circuit 200, it is necessary to ensure that the minimum distance between the test circuit 100 and the reference circuit 200 is less than or equal to 10 mm. That is, the minimum distance between the reference transistor unit 210 and the adjacent photosensitive transistor unit 110 or the auxiliary transistor unit 120 is less than or equal to 10 mm.

[0097] Furthermore, the inventors have found that conventional display devices use a discrete ambient light sensor solution, which integrates components such as a light detection structure and a camera module, and digs holes in the display area of ​​the display panel, and sets the integrated components in the holes in the display area of ​​the display panel. This structure has poor aesthetics.

[0098] To address this problem, the inventors have made the following improvements:

[0099] As shown in FIG9 , the display panel 10 includes a display area 11 and a non-display area 12. The light detection structure 20 is arranged in the driving control layer and is located in the non-display area 12. Through the above arrangement, the light detection structure 20 is integrated into the non-display area 12 to avoid excessive exposure of the light detection structure, so as to enhance the overall aesthetics.

[0100] In addition, the display panel 10 includes an inner light shielding layer and an outer light shielding layer. The inner light shielding layer is arranged on the side of the test circuit 100 and the reference circuit 200 close to the backlight source assembly to prevent the light emitted by the backlight source assembly from affecting the transistor unit. The outer light shielding layer is arranged above the light detection structure 20, that is, arranged on the side of the test circuit 100 and the reference circuit 200 away from the backlight source assembly. At the same time, a through light-transmitting hole is opened on the outer light shielding layer, and the positive projection of the photosensitive transistor unit 110 on the outer light shielding layer falls into the light-transmitting hole, thereby preventing the external ambient light from irradiating the auxiliary transistor unit 120 and the reference transistor unit 210, that is, the light-shielding treatment referred to above. At the same time, it is ensured that the photosensitive crystal can receive the external ambient light signal through the light-transmitting hole.

[0101] Furthermore, the light detection structure 20 can not only detect the brightness of the external light, but also adjust the brightness of the display panel 10 according to the detection result. At the same time, the color temperature can also be detected. Specifically, a color filter can be added to the side of the photosensitive transistor unit 110 away from the backlight assembly, and the color filter is located in the light-transmitting hole, or the positive projection of the light-transmitting hole along the thickness direction is located in the color filter, so that the external ambient light is first filtered by the color filter and then enters the photosensitive transistor unit 110 to realize the detection of color temperature.

[0102] At the same time, there are multiple light detection structures 20, and a color filter is provided on the photosensitive transistor unit 110 in each light detection structure 20. The colors of the color filters on at least two light detection structures 20 are different. For example, the number of light detection structures 20 can be 4, one of which is not provided with a color filter, and the other three light detection structures 20 are respectively provided with a red filter, a blue filter and a green filter, and multiple photosensitive transistor units 110 are used to perform color temperature detection and brightness detection of different colors, thereby realizing color temperature compensation, thereby improving the display effect.

[0103] It should be noted that the transistor units mentioned above are not composed of a single transistor TFT, but are formed by multiple TFTs connected in parallel (refer to FIG. 10 , which only provides a simple schematic diagram of the TFT in the photosensitive transistor). In this way, the area of ​​the transistor unit is increased, and its sensitivity to receiving light signals is increased.

[0104] In the present application, the structural embodiments and method embodiments may complement each other if they do not conflict.

[0105] In the present invention, the terms "first" and "second" are used for descriptive purposes only and cannot be understood as indicating or implying relative importance. The terms "plurality" and "several" refer to two or more than two, unless otherwise clearly defined.

[0106] Those skilled in the art will readily appreciate other embodiments of the present invention after considering the specification and practicing the disclosure disclosed herein. The present invention is intended to cover any variations, uses or adaptations of the present invention that follow the generality of the present invention and include common knowledge or customary techniques in the art that are not disclosed by the present invention. The description and examples are to be considered exemplary only, and the true scope and spirit of the present invention is indicated by the following claims.

[0107] It should be understood that the present invention is not limited to the exact construction that has been described above and shown in the drawings and that various modifications and changes may be made without departing from the scope thereof. The scope of the present invention is limited only by the appended claims.

Claims

A light detection structure, characterized in that: The light detection structure includes: a test circuit, including a photosensitive transistor unit and an auxiliary transistor unit connected in series, the photosensitive transistor unit is used to receive ambient light signals, and the auxiliary transistor unit is light-proof; when the light conditions of the photosensitive transistor unit and the auxiliary transistor unit are the same, the equivalent resistance values ​​of the two are the same; the control end of the photosensitive transistor unit is connected to the control end of the auxiliary transistor unit; a reference circuit, the signal input end of the reference circuit is connected to the signal input end of the test circuit; a signal processing module, including a first input end and a second input end, the signal processing module is used to compare the signals of the first input end and the second input end; the first input end is electrically connected to the signal output end of the photosensitive transistor unit; the second input end is electrically connected to the reference circuit. The light detection structure according to claim 1, characterized in that The test circuit and the reference circuit are commonly connected to a data terminal, and the electrical signal obtained by the second input terminal of the signal processing module is the electrical signal output by the data terminal. The light detection structure according to claim 1, characterized in that The reference circuit includes a reference transistor unit, which is light-proof; when the light conditions of the photosensitive transistor unit, the auxiliary transistor unit and the reference transistor unit are the same, the equivalent resistance values ​​of the three are the same; and the control end of the test circuit is connected to the control end of the reference circuit. The light detection structure according to claim 3, characterized in that The number of the reference transistor units is multiple, and the multiple reference transistor units are connected in series; and the number of the reference transistors is the same as the sum of the number of the photosensitive transistor units and the auxiliary transistor units in the test transistor; the number of the transistor units between the first input terminal and the control terminal of the test circuit is the same as the number of the transistor units between the second input terminal and the control terminal of the reference circuit. The light detection structure according to claim 4, characterized in that When the light signal received by the photosensitive transistor unit is less than or equal to a threshold value, the voltage signal on the first input terminal is equal to the voltage signal on the second input terminal; when the light signal received by the photosensitive transistor unit is greater than the threshold value, the voltage signal on the first input terminal is greater than the voltage signal on the second input terminal. The light detection structure according to claim 3, characterized in that The number of the reference transistors is different from the sum of the number of the photosensitive transistor units and the auxiliary transistor units in the test transistor; the number of the transistor units between the first input terminal and the control terminal of the test circuit is the same as or different from the number of the transistor units between the second input terminal and the control terminal of the reference circuit. The light detection structure according to claim 1, characterized in that There are multiple auxiliary transistor units, and a photosensitive transistor unit and an auxiliary transistor unit are provided between the first input end and the control end of the test circuit, or only a photosensitive transistor unit is provided between the first input end and the control end of the test circuit. The light detection structure according to claim 1, characterized in that The signal processing module includes an operational amplifier. The light detection structure according to claim 1, characterized in that The minimum distance between the photosensitive transistor unit and the adjacent auxiliary transistor unit is less than or equal to 10 mm; and / or the minimum distance between the test circuit and the reference circuit is less than or equal to 10 mm. A display panel, characterized in that: The display panel comprises the light detection structure as claimed in any one of claims 1 to 9. The display panel according to claim 10, characterized in that The display panel includes a display area and a non-display area, and the display panel also includes a drive control layer, the light detection structure is arranged in the drive control layer and is located in the non-display area; and / or the display panel includes an outer light shading layer, the outer light shading layer is arranged above the light detection structure, and a through light-transmitting hole is opened on the outer light shading layer, and the orthographic projection of the photosensitive transistor unit on the outer light shading layer falls into the light-transmitting hole. The display panel according to claim 10, characterized in that The display panel further comprises a backlight source assembly and a color filter, wherein the color filter is arranged on a side of the photosensitive transistor unit away from the backlight source assembly. The display panel according to claim 12, characterized in that There are multiple light detection structures, and the color filter is arranged on the photosensitive transistor unit in each of the light detection structures; and the colors of the color filters on at least two of the light detection structures are different. A display device, characterized in that The display device comprises the display panel as claimed in any one of claims 10 to 13.

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