Display device

Abstract

The embodiment of the invention discloses a display device. The display device comprises a display panel and a main controller, the display panel comprises a display area and a non-display area connected with the display area, and further comprises a plurality of temperature sensing devices. The temperature sensing device comprises a PN junction; the plurality of temperature sensing devices are located at different positions of the non-display area; the main controller is connected with the plurality of temperature sensing devices; the main controller is configured to sequentially obtain forward voltage drops of the two ends of the PN junctions in the temperature sensing devices under preset conduction current, and determine the temperatures of different positions where the temperature sensing devices are located in the non-display area according to the forward voltage drops. According to the embodiment of the invention, the problem of low temperature detection accuracy caused by the fact that the temperature sensing devices are arranged far away from a heat source in the existing temperature sensing technology is solved, the plurality of temperature sensing devices are directly integrated in the display panel, the temperature conditions of different positions of the display panel can be effectively and accurately detected, overheating protection can be conveniently carried out, and the user experience is improved. Heat damage of the panel is prevented, and the reliability and the service life of the display panel are guaranteed.

Description

Technical Field

[0001] This invention relates to the field of panel display technology, and more particularly to a display device. Background Technology

[0002] With the development of display technology, the application scenarios that require display are becoming more and more extensive. The actual operating environment of the display screen varies greatly in temperature. In order to avoid damage to the display screen due to extreme temperatures, temperature monitoring and overheat protection of the display screen have become important issues in the display field.

[0003] Existing temperature monitoring solutions for displays typically involve mounting temperature sensing elements (such as temperature-sensing ICs and thermistors) on a printed circuit board. The printed circuit board and other structures separate the temperature sensing elements from the display, which reduces the accuracy of the temperature detection of the panel surface. Consequently, the real-time power reduction and overheat protection based on this data are not ideal, affecting the reliability and lifespan of the display. Summary of the Invention

[0004] The present invention provides a display device that can accurately detect the temperature of various parts of the display panel by directly integrating a temperature sensing device on the display panel, thereby achieving accurate and effective temperature detection and helping to improve the reliability and service life of the display panel.

[0005] This invention provides a display device, including a display panel and a main controller; the display panel includes a display area and a non-display area connected to the display area, and also includes a plurality of temperature sensing devices; each temperature sensing device includes a PN junction; the plurality of temperature sensing devices are located at different positions in the non-display area;

[0006] The main controller is connected to the plurality of temperature sensing devices; the main controller is configured to sequentially acquire the forward voltage drop across the PN junction of each of the temperature sensing devices under a preset on-current, and determine the temperature of each of the temperature sensing devices at different locations in the non-display area based on the forward voltage drop.

[0007] The technical solution of this invention involves setting multiple temperature sensors in different positions within the non-display area of ​​the display panel. These temperature sensors are connected to a main controller, which sequentially acquires the forward voltage drop across the PN junction of each temperature sensor under a preset on-state current. Based on this forward voltage drop, the temperature at each location of the temperature sensor in the non-display area is determined. This enables temperature monitoring of various locations within the non-display area of ​​the display panel, avoiding the problem of low temperature detection accuracy caused by temperature sensors being located far from heat sources. Furthermore, by directly integrating multiple temperature sensors into the display panel, the temperature at different locations on the display panel can be effectively and accurately detected, allowing for monitoring of the temperature distribution across the entire front of the display panel. This improves the accuracy of temperature detection, facilitates power reduction when the temperature is too high, achieves overheat protection, prevents thermal damage to the panel, and ensures the reliability and lifespan of the display panel. Attached Figure Description

[0008] Figure 1 This is a schematic diagram of the rear structure of an automotive OLED display module in related technologies;

[0009] Figure 2 This is a schematic diagram of the structure of a display panel in a display device provided in an embodiment of the present invention;

[0010] Figure 3 This is a schematic diagram of the structure of a display panel in another display device provided in an embodiment of the present invention;

[0011] Figure 4 yes Figure 3 The diagram shows an equivalent circuit diagram of a temperature sensing system in a display device.

[0012] Figure 5 yes Figure 3 The diagram shows an equivalent circuit diagram of another temperature sensing system in the display device.

[0013] Figure 6 This is a schematic diagram of the structure of a display panel in another display device provided in an embodiment of the present invention;

[0014] Figure 7 yes Figure 6 The diagram shows an equivalent circuit diagram of a temperature sensing system in a display device.

[0015] Figure 8 yes Figure 2 The diagram shows a cross-sectional view of the display device along AA'.

[0016] Figure 9 yes Figure 2 A top view of the structure at point B (dashed box) in the display device shown;

[0017] Figure 10 yes Figure 2 A schematic diagram of part of the circuit structure of the display device shown.

[0018] Figure 11 This is a driving timing diagram of a display device provided in an embodiment of the present invention;

[0019] Figure 12 This is another driving timing diagram of the display device provided in the embodiment of the present invention. Detailed Implementation

[0020] The present invention will now be described in further detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and not intended to limit it. Furthermore, it should be noted that, for ease of description, the accompanying drawings show only the parts relevant to the present invention, and not all of the structures.

[0021] The terminology used in the embodiments of this invention is for the purpose of describing specific embodiments only and is not intended to limit the invention. It should be noted that directional terms such as "upper," "lower," "left," and "right" described in the embodiments of this invention are used to describe the angles shown in the accompanying drawings and should not be construed as limiting the embodiments of this invention. Furthermore, in the context, it should be understood that when referring to an element being formed "on" or "below" another element, it can be formed not only directly on or below the other element, but also indirectly on or below it through intermediate elements. The terms "first," "second," etc., are used for descriptive purposes only and do not indicate any order, quantity, or importance, but are merely used to distinguish different components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0022] The term "comprising" and its variations as used in this invention are open-ended, meaning "including but not limited to". The term "based on" means "at least partially based on". The term "one embodiment" means "at least one embodiment".

[0023] It should be noted that the concepts of "first" and "second" mentioned in this invention are only used to distinguish the corresponding contents and are not used to limit the order or interdependence.

[0024] It should be noted that the terms "a" and "a plurality of" used in this invention are illustrative rather than restrictive. Those skilled in the art should understand that, unless otherwise expressly indicated in the context, they should be understood as "one or more".

[0025] The following section uses an automotive display panel as an example to introduce existing temperature monitoring solutions for display panels. First, automotive display modules typically operate within a temperature range of -40 to 85°C. Under high-temperature conditions, to prevent the display module from overheating and causing panel failure, the module needs a power reduction design. This means that the display power of the panel needs to be appropriately reduced at higher temperatures to minimize heat generation. For LCD display modules, heat generation is usually concentrated on the backlight strips and the driver chip (Integrated Circuit, IC). Therefore, thermistors are generally placed near the backlight strips and driver IC to accurately monitor the temperature.

[0026] However, for automotive organic light-emitting diode (OLED) display modules, the heat sources are mainly OLED devices, printed circuit boards (PCBs), and chip on film (COF). After they are superimposed, the high-temperature position on the front of the display module is not fixed due to the influence of the position design of the driver IC. Figure 1 This is a schematic diagram of the rear structure of an automotive OLED display module in related technologies, for reference. Figure 1 In automotive OLED display modules, temperature sensing devices 10, such as temperature sensors or thermistors, are typically mounted on a PCB 80 and folded back onto the back of the display panel for temperature monitoring. Because the temperature sensing device 10 is separated from the display panel by multiple layers of film, including the PCB 80, adhesive tape, and aluminum plates, it can only monitor the temperature of a localized area on the back side. It is difficult to monitor the temperature distribution across the entire front of the display panel, reducing the accuracy of surface temperature detection, affecting overheat protection, and potentially causing thermal damage to the display panel.

[0027] To address the aforementioned technical problems, embodiments of the present invention provide a display device. Figure 2 This is a schematic diagram of the structure of a display panel in a display device provided in an embodiment of the present invention, with reference to... Figure 2 The display device includes a display panel and a main controller. Figure 2 (Not shown in the image). The display panel includes a display area AA and a non-display area NA connected to the display area AA, and also includes multiple temperature sensors 10; each temperature sensor 10 includes a PN junction; the multiple temperature sensors 10 are located at different positions in the non-display area NA. The main controller is connected to the multiple temperature sensors 10; the main controller is configured to sequentially acquire the forward voltage drop across the PN junction of each temperature sensor 10 under a preset on-state current, and determine the temperature at different positions of each temperature sensor 10 in the non-display area NA based on the forward voltage drop.

[0028] The display panel is divided into a display area AA and a non-display area NA. As those skilled in the art will understand, the display area AA is equipped with light-emitting devices 70. By illuminating each light-emitting device 70 with a specific color, they can be matched to each other to achieve the display function. The non-display area NA typically contains a driving circuit to drive the light-emitting devices 70 to illuminate. In this embodiment of the invention, temperature sensors 10 are also installed at different locations in the non-display area NA. These sensors can not only detect the temperature distribution of the display panel from different locations in the non-display area NA, accurately monitor the heat dissipation during the operation of the display panel, and thus precisely adjust for overheating, but also avoid occupying space in the display area and affecting the resolution of the display area.

[0029] In this embodiment of the invention, a PN junction is provided in the temperature sensing device 10. Essentially, temperature detection is achieved by utilizing the electrical characteristics of the PN junction. Specifically, under constant current bias, the forward voltage drop of the PN junction decreases approximately linearly with increasing temperature. Its electrical characteristic formula can be linearly approximated as: VBE(T) = VBE(T0) + k × (T - T0), where VBE(T) is the forward voltage drop of the PN junction at temperature T, VBE(T0) is the initial forward voltage drop of the PN junction at initial temperature T0, and k ≈ -2mV / °C. The physical reason for this electrical characteristic is that the intrinsic carrier concentration ni of the semiconductor material increases exponentially with temperature, leading to a decrease in the junction voltage VBE required to maintain the current at the same current. Therefore, given the initial temperature T0 and the initial forward voltage drop VBE(T0) at initial temperature T0, the temperature T of the current location of the PN junction can be calculated by detecting the actual forward voltage drop VBE(T) of the PN junction, thus achieving temperature detection. The initial temperature T0 and the initial forward voltage drop VBE(T0) need to be calibrated in advance. The initial temperature T0 can be understood as a pre-set temperature value. Under this pre-set temperature value, the voltage difference across the PN junction can be calibrated to obtain a definite forward voltage drop, which is the initial forward voltage drop. Based on these two calibration parameters, the difference T-T0 between the current PN junction temperature T and the initial temperature T0 can be calculated according to the actual detected voltage difference across the PN junction, i.e., the actual forward voltage drop VBE(T). Thus, the current PN junction temperature T can be obtained.

[0030] Furthermore, it should be emphasized that in this embodiment of the invention, multiple temperature sensors 10 are provided at different locations in the non-display area NA to detect the temperature at different locations on the display panel. This facilitates precise adjustment and control of temperature anomalies, such as overheating, at different locations on the display panel. Figure 2As illustrated, the temperature sensing devices 10 can be evenly distributed in the non-display area NA. Based on the arrangement of multiple temperature sensing devices 10, the present invention sequentially provides a preset conduction current to the PN junctions via a main controller and sequentially detects the forward voltage drop across each junction. This allows for the calculation of the temperature at each PN junction location, thus enabling temperature monitoring at different locations within the non-display area NA where each temperature sensing device 10 is located. Furthermore, the main controller can be understood as an external control unit of the display panel, which connects to the display panel via wiring, thereby connecting to the various temperature sensing devices 10 on it to achieve the temperature detection function.

[0031] The above technical solution, by setting multiple temperature sensors in different positions within the non-display area of ​​the display panel and connecting them to the main controller, allows the main controller to sequentially acquire the forward voltage drop across the PN junction of each temperature sensor under a preset on-state current. Based on this forward voltage drop, the temperature at different locations within the non-display area of ​​each temperature sensor can be determined. This enables temperature monitoring of various locations within the non-display area of ​​the display panel, avoiding the problem of low temperature detection accuracy caused by temperature sensors being located far from heat sources. Furthermore, because multiple temperature sensors are directly integrated into the display panel, the temperature at different locations on the display panel can be effectively and accurately detected, allowing for monitoring of the temperature distribution across the entire front of the display panel. This improves the accuracy of temperature detection, facilitates power reduction when the temperature is too high, achieves overheat protection, prevents thermal damage to the panel, and ensures the reliability and lifespan of the display panel.

[0032] In one specific embodiment, the temperature sensing device 10 optionally includes a diode and a bipolar transistor.

[0033] For a diode, which contains a PN junction, the voltage difference between the positive and negative terminals can be detected by the main controller. For a bipolar junction transistor (BJT), which is essentially composed of two back-to-back PN junctions, including an emitter, base, and collector, the voltage difference between the base and emitter can be detected by the main controller.

[0034] In one specific embodiment, optionally, the ion doping concentration C of the P-type doped region 4011 and the N-type doped region 4012 in the PN junction satisfies: C ≥ 1 × 10⁻⁶ 18 cm -3 .

[0035] In this embodiment, the ion concentration in the doped region of the PN junction is limited to improve its temperature detection sensitivity. Specifically, a highly doped PN junction exhibits a more significant voltage difference change under the same temperature variation, meaning it is more sensitive and can more accurately detect the temperature at its location. Taking a bipolar transistor as an example, the voltage difference between its base and emitter, VBE, is calculated as VBE = (kT / q) × ln(I_F / Is); where T is the temperature, k / q is a constant (approximately 86 μV / K), I_F is the preset on-state current, and Is is the reverse saturation current. A higher ion concentration in the doped region of the PN junction indicates a larger Is. Under the same preset on-state current I_F, according to the above formula, the ln(I_F / Is) term decreases, thus reducing the value of VBE. Based on the temperature coefficient formula... Where VG0 is the bandgap voltage of silicon, approximately 1.17V, and γ is a constant related to the temperature coefficient of mobility, typically 3-4. When the initial VBE decreases, VG0 = 1.17V remains unchanged. Substituting this into the temperature coefficient formula, we can see that the term [VBE(T) - VG0] becomes a larger negative number. Therefore, the negative value of the term [VBE(T) - VG0] / T also becomes larger, ultimately affecting the overall temperature coefficient. It will shift towards a more negative direction, and its absolute value |∂VBE / ∂T| will increase, thereby achieving higher temperature sensitivity. In this embodiment of the invention, the ion doping concentration C is limited to not less than 1×10⁻⁶. 18 cm -3 It can achieve a temperature conversion coefficient of -2mV / ℃ or even higher, realizing high-precision temperature detection of ±0.3℃, which helps to improve the signal-to-noise ratio and accuracy of subsequent detection circuits. Compared with traditional thermistors, the temperature detection accuracy can be improved by more than 50%.

[0036] Figure 3 This is a schematic diagram of the structure of a display panel in another display device provided in an embodiment of the present invention. Figure 4 yes Figure 3 The diagram shown is an equivalent circuit diagram of a temperature sensing system in a display device. (Refer to...) Figure 3 and Figure 4 Optionally, the multiple temperature sensing devices 10 include multiple groups of temperature sensing devices 100, and the number of temperature sensing devices 10 in each group of temperature sensing devices 100 is the same.

[0037] The display panel also includes multiple gate lines 21 and multiple read lines 22. The number of gate lines 21 is the same as the number of temperature sensing device groups 100, and the number of read lines 22 is the same as the number of temperature sensing devices 10 in a group of temperature sensing device groups 100. Each gate line 21 connects to each temperature sensing device 10 in a group of temperature sensing device groups 100 and is connected to the first pole of each temperature sensing device 10. Different gate lines 21 connect to different groups of temperature sensing device groups 100. Each read line 22 connects to one temperature sensing device 10 in a group of temperature sensing device groups 100 and is connected to the second pole of each temperature sensing device 10. Different read lines 22 connect to different temperature sensing devices 10 in different groups of temperature sensing device groups 100.

[0038] The main controller 30 is connected to the gating line 21 and the reading line 22 respectively. The main controller 30 is configured to provide a preset conduction current to the gating line 21 and determine the forward voltage drop based on the voltage difference between the gating line 21 and the reading line 22.

[0039] Those skilled in the art will understand that, due to the limited space of the display panel, the area of ​​the non-display area NA determines the size of the bezel of the display device. When the non-display area NA is equipped with corresponding signal traces for each temperature sensing device 10 connected to the main controller 30, an excessive number of signal traces will greatly increase the area of ​​the non-display area NA. To address this problem, this embodiment essentially divides the temperature sensing devices 10 in the non-display area NA into multiple groups of temperature sensing devices 100 according to their location. The scheme involves sequentially addressing and scanning the temperature sensing devices 10 in each group of temperature sensing devices 100 using the selection line 21 and the read line 22 to obtain the detection voltage of each temperature sensing device 10. Specifically, refer to... Figure 3Optionally, multiple temperature sensing devices 10 located near each other in the non-display area NA can be divided into a temperature sensing device group 100. The first pole of each of the multiple temperature sensing devices 10 located near each other is connected to a gate line 21, and the second pole is connected to different reading lines 22. A fixed current, i.e. a preset conduction current, is provided to each temperature sensing device 10 in the temperature sensing device group 100 by the gate line 21. The voltage on each reading line 22 is read in sequence, and the difference between the voltage on the gate line 21 and the voltage on the gate line 21 is used to obtain the voltage difference between the two poles of each temperature sensing device 10 in the temperature sensing device group 100, i.e., VBE(T). Then, the actual temperature T at the current location can be calculated by using the conversion formula VBE(T)=VBE(T0)+k×(T-T0) and the pre-calibrated parameters VBE(T0) and T0. Therefore, it can be understood that the number of temperature sensing device groups 100 divided by the temperature sensing device 10 in the non-display area NA is the number of gate lines 21 that need to be set, and the number of temperature sensing devices 10 in the temperature sensing device group 100 is the number of reading lines 22 that need to be set. This can greatly reduce the signal routing between the temperature sensing device 10 and the main controller 30. Based on effectively reading the actual temperature of each temperature sensing device 10, the area of ​​the non-display area of ​​the display panel is saved, and the burden of the panel integrated temperature sensing system on the layout of the non-display area is reduced to a certain extent.

[0040] It should be noted that when the temperature sensing device is a diode, the first terminal of the temperature sensing device connected to the pass line 21 can be the positive terminal, and the second terminal of the temperature sensing device connected to the read line 22 can be the negative terminal. When the temperature sensing device is a bipolar transistor, the first terminal of the temperature sensing device connected to the pass line 21 can be its base, and the second terminal of the temperature sensing device connected to the pass line 21 can be its emitter. Of course, those skilled in the art can also choose to use the opposite connection method as described in the above examples according to actual needs, and there is no limitation here.

[0041] Figure 5 yes Figure 3 The diagram shown is an equivalent circuit diagram of another temperature sensing system in the display device. (Refer to...) Figure 3 and Figure 5 Optionally, the display panel also includes at least one multiplexer 23, which includes multiple input terminals and one output terminal. Each input terminal of the at least one multiplexer 23 is connected to a corresponding read line 22, and the output terminal of the at least one multiplexer 23 is connected to the main controller 30.

[0042] The main controller 30 is configured to acquire the voltage difference between the target selection line 21 and the target reading line 22 when each input terminal of the multiplexer 23 is sequentially selected with the output terminal, and determine the forward voltage drop across the PN junction in the target temperature sensing device 10 under a preset conduction current; wherein, the target selection line 21 is the selection line 21 that receives the preset conduction current provided by the main controller 30, the target reading line 22 is the reading line 22 connected to the input terminal selected with the output terminal, and the target temperature sensing device 10 is the temperature sensing device 10 connected to the target selection line 21 and the target reading line 22 respectively.

[0043] In this embodiment, by setting a multiplexer 23, any one of the paths of the multiplexer 23 can be controlled by a gating control signal. For example, when controlling the first path of the multiplexer 23 to be turned on, realizing the connection between the first read line 22 and the main controller 30, the main controller 30 can synchronously and sequentially obtain the voltage on the first read line by providing a preset conduction current to each gating line 21 in sequence, that is, sequentially obtain the voltage of the temperature sensing device 10 in each temperature sensing device group 100 connected to the first read line, thereby realizing the addressing scan of the temperature sensing device 10 in each temperature sensing device group 100 connected to the first read line. Similarly, when each path of the control multiplexer 23 is turned on, and each reading line is connected to the main controller 30, the voltage of the temperature sensing device 10 in each temperature sensing device group 100 on the multiple currently turned-on reading lines can be synchronously and sequentially provided with a preset on current to each selection line 21. In this way, the addressing and scanning of all temperature sensing devices 10 can be realized, and the temperature data of the location of each temperature sensing device 10 can be obtained.

[0044] It should be added that, such as Figure 5 The example only shows one multiplexer 23. Those skilled in the art can configure multiple multiplexers to achieve addressing and scanning of each temperature sensor according to actual needs, such as when there are many temperature sensor groups or many temperature sensors. Figure 5 In the example, a temperature sensing device group 100 is respectively arranged in the four areas above, below, left, and right of the non-display area NA. Those skilled in the art may also choose to arrange multiple temperature sensing device groups in these four areas, and use a multiplexer for scanning and addressing the temperature sensing device groups in the same area; no restrictions are imposed here. Furthermore, as... Figure 4 and Figure 5 The equivalent circuit diagram shown only illustrates the connection relationship and is used to explain the addressing and scanning scheme of each temperature sensor in each temperature sensor group by the main controller. The components, wiring, size, position relationship, and arrangement of the main controller are not for reference.

[0045] Figure 6 This is a schematic diagram of the structure of a display panel in another display device provided in an embodiment of the present invention. Figure 7 yes Figure 6The equivalent circuit diagram of the temperature sensing system in the display device shown is for reference. Figure 3 , Figure 6 and Figure 7 Optionally, the non-display area NA includes a first sub-area NA1, a second sub-area NA2, a third sub-area NA3, and a fourth sub-area NA4; the first sub-area NA1 and the second sub-area NA2 are located on opposite sides of the display area AA in the first direction X, and the third sub-area NA3 and the fourth sub-area NA4 are located on opposite sides of the display area AA in the second direction Y; wherein the first direction X and the second direction Y intersect.

[0046] The multiple temperature sensing devices 10 include a first temperature sensing device array 101, a second temperature sensing device array 102, a third temperature sensing device array 103, and a fourth temperature sensing device array 104. The first temperature sensing device array 101 is located in a first sub-region NA1, the second temperature sensing device array 102 is located in a second sub-region NA2, the third temperature sensing device array 103 is located in a third sub-region NA3, and the fourth temperature sensing device array 104 is located in a fourth sub-region NA4. The temperature sensing devices 10 in the first temperature sensing device array 101 and the second temperature sensing device array 102 are arranged in an M×N array along the first direction X and the second direction Y. The temperature sensing devices 10 in the third temperature sensing device array 103 and the fourth temperature sensing device array 104 are arranged in an N×M array along the first direction X and the second direction Y. Wherein, M and N are positive integers.

[0047] In this context, the first sub-region NA1 and the second sub-region NA2 can be understood as the left and right non-display areas, respectively, and the third sub-region NA3 and the fourth sub-region NA4 can be understood as the upper and lower non-display areas, respectively. The temperature sensing devices 10 located in the first and second sub-regions NA1 and NA2, and the temperature sensing devices 10 located in the third and fourth sub-regions NA3 and NA4, can all be arranged in an array configuration, forming a first temperature sensing device array 101, a second temperature sensing device array 102, a third temperature sensing device array 103, and a fourth temperature sensing device array 104, respectively. Furthermore, considering that the upper and lower non-display areas extend in the left-right direction, and the left and right non-display areas extend in the up-down direction, they can be arranged in the same array configuration with a 90-degree relative rotation, ensuring that the four sub-regions of the non-display area have the same number of temperature sensing devices 10 and a similar temperature sensing layout. For example... Figure 3 For example, the first temperature sensing device array 101 and the second temperature sensing device array 102 can be configured as an array of 1 row and 8 columns, with each row representing a group of temperature sensing devices 100; the third temperature sensing device array 103 and the fourth temperature sensing device array 104 can be configured as an array of 1 column and 8 rows, with each column representing a group of temperature sensing devices 100. Figure 6 and Figure 7For example, the first temperature sensing device array 101 and the second temperature sensing device array 102 can be set as an array of 4 rows and 8 columns. Similarly, each row can be understood as a group of temperature sensing devices 100. The third temperature sensing device array 103 and the fourth temperature sensing device array 104 can be set as an array of 4 columns and 8 rows. Similarly, each column can be understood as a group of temperature sensing devices 100.

[0048] It should be noted that the arrangement of the four temperature-sensing device arrays described above is merely an example; the specific number of rows and columns within each sub-region is not limited in this embodiment. In one specific embodiment, optionally, the number of temperature-sensing devices does not exceed 128. For example... Figure 6 and Figure 7 For example, setting 32 temperature sensors in each of the four sub-areas can actually form a 16×8 two-dimensional array of 128 sensors. Since 128 temperature detection points mean a sufficiently dense temperature detection network can be formed on the display panel, the density is already sufficient to accurately capture local hot spots and overall temperature gradient changes. Increasing the number of temperature detection points further would have very limited improvement on the overall detection accuracy of the temperature sensing system. Furthermore, since each temperature sensor needs to be connected to the reading circuit via a signal line, 128 temperature detection points already require fairly complex internal wiring. When the number of temperature detection points increases, for example to 256, the wiring density will increase dramatically, occupying even more valuable panel space.

[0049] Figure 8 yes Figure 2 The diagram shown is a cross-sectional view of the display device along AA'. (Refer to...) Figure 2 and Figure 8 Optionally, the display panel further includes a substrate 1, a driving circuit layer 2, an insulating layer 3, and a temperature sensing device layer 4; the driving circuit layer 2, the insulating layer 3, and the temperature sensing device layer 4 are stacked sequentially in a direction perpendicular to the substrate 1 and away from the substrate 1; the temperature sensing device 10 is formed in the temperature sensing device layer 4.

[0050] The driving circuit layer 2 can be understood as a circuit structure layer in the display panel used to drive the light-emitting device 70 to light up. As those skilled in the art know, on the substrate 1 of the display panel, the display area AA needs to be provided with pixel circuits, and the non-display area NA needs to be provided with gate scanning circuits. The gate scanning circuit is connected to the pixel circuits and can provide scanning signals to the pixel circuits to control the pixel circuits to drive the corresponding connected light-emitting device 70 to light up. Therefore, the driving circuit layer 2 here can include a circuit structure layer composed of pixel circuits and gate scanning circuits. Based on this, in this embodiment of the invention, a temperature sensing device layer 4 is provided on the driving circuit layer 2 in the non-display area NA to fabricate and form multiple temperature sensing devices 10. It can be understood that, to avoid mutual interference between the circuit structures of the temperature sensing devices 10 and the driving light-emitting device 70, an insulating layer 3 can be provided between the temperature sensing device layer 4 and the driving circuit layer 2 for insulation.

[0051] Figure 9 yes Figure 2 The diagram shows a top view of the structure at point B within the dashed box of the display device. (Refer to...) Figure 2 , Figure 8 and Figure 9 Furthermore, the temperature sensing device layer 4 may include a semiconductor layer 401 and an electrode layer 402; the semiconductor layer 401 includes a plurality of device regions 4010, and the device regions 4010 include an intrinsic isolation region 4013, a P-type doped region 4011 and an N-type doped region 4012; the P-type doped region 4011 and the N-type doped region 4012 are respectively located on opposite sides of the intrinsic isolation region 4013 in the direction parallel to the substrate 1; the semiconductor layer 401 of the P-type doped region 4011 is doped with an acceptor element, and the semiconductor layer 401 of the N-type doped region 4012 is doped with a donor element; the semiconductor layers 401 of the intrinsic isolation region 4013, the P-type doped region 4011 and the N-type doped region 4012 constitute a temperature sensing device 10. The electrode layer 402 includes an anode 4021 and a cathode 4022. The anode 4021 covers the side surface of the semiconductor layer 401 of the P-type doped region 4011 that is away from the driving circuit layer 2, and the cathode 4022 covers the side surface of the semiconductor layer 401 of the N-type doped region 4012 that is away from the driving circuit layer 2.

[0052] The aforementioned temperature sensing device 10 is essentially a typical PIN junction. This structure allows the temperature sensing device 10 to possess advantages such as efficient carrier injection, fast switching response, and high breakdown voltage. Specifically, in this PIN junction, the P-type doped region 4011 injects holes into the intrinsic region under forward bias, while the N-type doped region 4012 injects electrons. The intrinsic region, as a key area for carrier transport and recombination, accommodates and promotes carrier recombination under forward bias, and is completely depleted under reverse bias to withstand high voltage and reduce junction capacitance. The anode 4021 and cathode 4022 are used to achieve electrical connection with external circuits.

[0053] It should be added that, optionally, the PIN junction can be annealed after the above-mentioned PIN junction fabrication is completed. Those skilled in the art will know that after the PIN junction is fabricated, for example, when forming the P-type doped region 4011 and the N-type doped region 4012 through ion implantation, the crystal structure is damaged, and the implanted impurity atoms are located in non-electrolyzable interstitial positions. This embodiment, by adding an annealing step, can, on the one hand, activate the impurities, providing high energy in a very short time, causing the impurity atoms to move to lattice positions and become electrically active atoms capable of providing charge carriers, thereby forming good PN junction characteristics; on the other hand, it can repair the damage to the silicon lattice caused during ion implantation, reducing defects and leakage current; furthermore, it can ensure good ohmic contact with the subsequent metallization of the PN junction electrode, reducing contact resistance. By using rapid annealing, for example, at 450°C for 30 seconds, the thermal compatibility problem between organic materials and semiconductor devices can be solved, achieving a balance between the PN junction activation quality and the protection of the OLED organic layer.

[0054] Continue to refer to Figure 3 , Figure 8 and Figure 9 In an optional embodiment, the semiconductor layer 401 of the temperature sensing device layer 4 may further include a shallow trench isolation region 4014, which is located between adjacent device regions 4010 in the direction parallel to the substrate 1.

[0055] The shallow trench isolation region 4014 is essentially a trench filled with an insulating medium such as silicon dioxide. The core function of setting the shallow trench isolation region 4014 between adjacent PIN junctions, i.e., between the temperature sensing devices 10, is to achieve electrical isolation. Specifically, the shallow trench isolation region 4014 can physically block parasitic conductive paths that may form between adjacent devices, effectively suppressing leakage current generated by surface states, thereby preventing leakage current and signal crosstalk between devices. Setting the shallow trench isolation region 4014 for multiple independently operating temperature sensing PIN junctions is crucial for ensuring the independent operating characteristics of each device, improving breakdown voltage, and reducing the overall circuit's static power consumption.

[0056] Continue to refer to Figure 3 , Figure 8 and Figure 9 Optionally, the thickness D1 of the driving circuit layer 2 ranges from 0.2 to 0.5 μm, and / or the thickness D2 of the insulating layer 3 ranges from 0.3 to 1.5 μm, and / or the thickness D3 of the semiconductor layer 401 ranges from 0.1 to 0.5 μm.

[0057] The thickness of the insulating layer 3 is set between 0.3 and 1.5 μm, ensuring sufficient thickness to effectively isolate the temperature sensing device 10 from the driving circuit of the display panel itself. The thickness of the semiconductor layer 401 is set between 0.1 and 0.5 μm, allowing the PIN junction to have sufficient thickness for P-type and N-type ion doping. Furthermore, these ranges also limit the excessive thickness of the insulating layer 3 and the semiconductor layer 401, preventing an increase in the overall thickness of the display panel.

[0058] Continue to refer to Figure 3 , Figure 8 and Figure 9 Optionally, the size range of device region 4010 is greater than or equal to 20μm×20μm, and the spacing L1 between adjacent device regions 4010 is not less than 1mm.

[0059] By adopting a miniaturized design of 20×20μm² or larger, the PIN junction can be rapidly cooled to ambient temperature between two measurements to reduce self-heating and avoid affecting the temperature measurement accuracy of the temperature sensing device 10. This forms a fully functional PN junction that can carry the small bias current (such as tens of microamps) required for measurement and generate a measurable voltage signal with a sufficient signal-to-noise ratio.

[0060] Figure 10 yes Figure 2 The schematic diagram of a portion of the circuit structure of the display device shown is for reference. Figure 2 and Figure 10 Specifically, the display panel also includes a front-end circuit 40, which includes a differential amplifier circuit 41 and an analog-to-digital converter circuit 42. The front-end circuit 40 is connected between the temperature sensing device 10 and the main controller 30. The differential amplifier circuit 41 is connected to the two ends of the PN junction in the temperature sensing device 10 and is used to amplify and output the positive voltage across the PN junction. The analog-to-digital converter circuit 42 is connected to the differential amplifier circuit 41 and is used to convert the amplified positive voltage from an analog signal to a digital signal and provide it to the main controller 30.

[0061] The front-end circuit 40 can be understood as a front-end data processing circuit before the main controller 30 performs calculations. It is used to process the voltage signal fed back by the temperature sensing device 10 so that the main controller 30 can read and calculate it into temperature data. As mentioned above, the temperature sensing devices 10 in the display panel can form a temperature sensing device array, which is addressed and scanned through the gate line 21 and the read line 22. Based on this, the gate line 21 and the read line 22 can be connected to the front-end circuit 40. Through the differential amplifier circuit 41 in the front-end circuit 40, the weak differential signal on the gate line 21 and the read line 22, that is, the positive voltage across the PN junction, can be amplified, and then converted into a digital voltage signal through analog-to-digital conversion and provided to the main controller 30.

[0062] Alternatively, the front-end circuit 40 may further include an electrostatic discharge protection circuit 43 and a low-pass filter circuit 44; the electrostatic discharge protection circuit 43 and the low-pass filter circuit 44 are connected in sequence between the temperature sensing device 10 and the differential amplifier circuit 41.

[0063] In addition, to avoid interference from external static electricity, electromagnetic fields, etc., in this embodiment of the invention, an electrostatic protection circuit 43 and a low-pass filter circuit 44 can be provided in the front-end circuit 40. The electrostatic protection circuit 43 can release the static electricity generated on the display panel, and the low-pass filter circuit 44 can shield the interference of external electromagnetic signals, thereby avoiding damage to the main controller 30 caused by static electricity and avoiding interference from electromagnetic signals with the temperature detection accuracy of the main controller 30.

[0064] Further optionally, the display panel also includes a driver chip 50; the front-end circuitry 40 is integrated into the driver chip 50; the display device also includes I... 2 The temperature sensor 10 is connected to the driver chip 50 via the C-bus, and the driver chip 50 communicates with the driver chip 50 through I-bus. 2 The C bus is connected to the main controller 30.

[0065] Alternatively, the display panel may further include a plurality of light-emitting devices 70 located in the display area AA; the driving chip 50 may also integrate a gate driving circuit 51 and a source driving circuit 52, and the light-emitting devices 70 are connected to the gate driving circuit 51 and the source driving circuit 52 respectively.

[0066] The front-end circuit 40, as a dedicated "analog front-end" module, is integrated into the driver chip 50 along with the gate drive, source drive, and timing control circuits required for the display panel. This significantly shortens the transmission distance of the voltage analog signal of the temperature sensing device 10 on the panel, minimizing the possibility of interference and ensuring the quality of the detection signal from the temperature sensing device 10, thus improving the accuracy of temperature detection. Furthermore, since the front-end circuit 40, gate drive circuit 51, and source drive circuit 52 are all integrated into the driver chip 50, high integration can be achieved, eliminating the need for additional external chips, saving space and cost. Additionally, the temperature sensing system and display function can share a power management unit, optimizing power consumption control. In other words, by integrating the front-end circuit 40 into the driver chip 50, deep integration of temperature sensing and display at the physical and protocol layers can be achieved, forming a truly intelligent display system, rather than a simple stacking. Optionally, the driver chip 50 can be located in the non-display area NA of the display panel, or it can be placed on a flexible circuit board using COF technology; neither is limited here.

[0067] Furthermore, the I²C bus is a multi-master, half-duplex serial bus that supports multiple devices. It includes clock and data lines and has a robust protocol, making it ideal for transmitting low-speed, small-batch control and sensing data such as temperature. In this embodiment, the driver chip 50 and the main controller 30 transmit data via the I²C bus. This utilizes the existing display control I²C bus to transmit temperature data, avoiding the need for separate signal lines for temperature sensors, reducing the number of pins and wiring in the main controller 30, and lowering cost, complexity, and failure rate.

[0068] Figure 11 This is a driving timing diagram of a display device provided in an embodiment of the present invention, for reference. Figure 2 and Figure 11 First, in this embodiment of the invention, the display panel further includes multiple light-emitting devices 70, which are located in the display area AA; the light-emitting devices 70 are connected to the main controller. The driving process of the display device includes multiple display frames T, each display frame T including a display stage t1 and a temperature sensing stage t2, with the temperature sensing stage t2 located after the display stage t1.

[0069] The main controller is also configured to: in the display phase t1, drive the light-emitting device 70 to display according to the preset driving voltage corresponding to the current display frame T; in the temperature sensing phase t2, provide a preset conduction current to the temperature sensing device 10, obtain the forward voltage drop across the PN junction in the temperature sensing device 10 under the preset conduction current, and determine the temperature at the location of the temperature sensing device 10 based on the forward voltage drop.

[0070] First, the temperature sensing stage t2 can be understood as temperature sensing occurring during the vertical blanking period between two adjacent display stages t1. When the light-emitting device 70 is driven to display, it generates heat, allowing real-time monitoring of various positions on the display panel during the temperature sensing stage t2. The display panel driving process provided in this embodiment is essentially a time-division multiplexing process of the main controller, requiring precise timing coordination with the driver chip 50 and the temperature sensing device 10. The time-division multiplexing process of the main controller is described below:

[0071] During the display phase t1, the main controller is responsible for driving the light-emitting device 70 of the display area AA to light up. It can first provide display instructions and parameters to the driver chip 50, such as brightness data and gamma correction values. The driver chip 50 generates pixel-level waveforms according to the instructions and parameters and provides them to the light-emitting device 70 to realize the display.

[0072] During the temperature sensing stage t2, the main controller sends a temperature sampling command to the temperature sensing device in the non-display area NA via the I²C bus, which means providing a preset conduction current to the temperature sensing device. Then, the 128 temperature sensing devices 10 transmit a data packet of 128 nodes × 2 bytes via the I²C bus, which can sequentially realize addressing scanning, differential amplification, analog-to-digital conversion, temperature calculation, etc., to obtain the current temperature data of each temperature sensing device 10.

[0073] Figure 12 This is another driving timing diagram of the display device provided in the embodiment of the present invention, for reference. Figure 2 and Figure 12 In another embodiment of the present invention, a compensation calculation stage t3 may be set in the display frame T, which is located after the temperature sensing stage t2. The main controller is also configured to: in the compensation calculation stage t3, correct the preset driving voltage corresponding to the light-emitting device 70 adjacent to the temperature sensing device 10 in the next display frame T according to the temperature at the location of the temperature sensing device 10.

[0074] The compensation calculation stage t3 is also set within the vertical blanking period between two adjacent display stages t1, or it can be understood as before the next display stage t1. The compensation calculation stage t3 mainly uses the temperature data of various parts of the display panel collected in the temperature sensing stage t2 to adjust the display of the light-emitting device 70 at the corresponding position. Specifically, those skilled in the art will understand that in the display stage t1, since different display frames T will have corresponding display images, it is necessary to provide a specific preset driving voltage to the light-emitting device 70 so that it emits light according to the preset brightness to form the set display image. In this embodiment, the temperature data of various parts of the display panel detected in the temperature sensing stage t2 can be used to correct the preset driving voltage of the next display stage t1, so as to adjust the heat generation of the light-emitting device 70 in the corresponding area and keep the temperature of the corresponding area of ​​the control panel within the standard temperature range. Specifically, based on the temperature at the location of the temperature sensing device 10, a pulse width modulation (PWM) compensation algorithm can be run to change the duty cycle of the effective pulse of the driving voltage and control the flicker frequency of the light-emitting device 70. In this way, when the display panel is locally overheated, the flicker frequency of the light-emitting device 70 can be reduced by decreasing the pulse width of the driving voltage, thus preventing the light-emitting device 70 from continuously lighting up and generating heat, thereby stabilizing the local temperature, achieving thermal protection of the display panel, and improving the service life of the display panel.

[0075] Note that the above description is merely a preferred embodiment of the present invention and the technical principles employed. Those skilled in the art will understand that the present invention is not limited to the specific embodiments described herein, and various obvious changes, readjustments, combinations, and substitutions can be made without departing from the scope of protection of the present invention. Therefore, although the present invention has been described in detail through the above embodiments, the present invention is not limited to the above embodiments, and may include many other equivalent embodiments without departing from the concept of the present invention, the scope of which is determined by the scope of the appended claims.

Claims

1. A display device, characterized by comprising: The display panel comprises a display area and a non-display area connected with the display area, and further comprises a plurality of temperature sensing devices; the temperature sensing device comprises a PN junction; the plurality of temperature sensing devices are located at different positions of the non-display area; The main controller is connected with the plurality of temperature sensing devices; the main controller is configured to sequentially acquire a forward voltage drop of the PN junction under a preset conduction current, and determine a temperature of a different position of each temperature sensing device in the non-display area according to the forward voltage drop.

2. The display device according to claim 1, wherein The plurality of temperature sensing devices comprise a plurality of temperature sensing device groups, and the number of temperature sensing devices in each temperature sensing device group is the same; The display panel further comprises a plurality of gate lines and a plurality of read lines; the number of gate lines is the same as the number of temperature sensing device groups, and the number of read lines is the same as the number of temperature sensing devices in a temperature sensing device group; The gate line is connected with each temperature sensing device in a temperature sensing device group and connected with a first electrode of the temperature sensing device, and different gate lines are connected with different temperature sensing device groups; The read line is connected with a temperature sensing device in each temperature sensing device group and connected with a second electrode of the temperature sensing device, and different read lines are connected with different temperature sensing devices in different temperature sensing device groups; The main controller is connected with the gate line and the read line respectively, and the main controller is configured to sequentially provide the preset conduction current to the gate line and determine the forward voltage drop according to a voltage difference between the gate line and the read line.

3. The display device according to claim 2, wherein The display panel further comprises at least one multiplexer, and the multiplexer comprises a plurality of input ends and an output end; Each input end of the at least one multiplexer is connected with the read line one by one, and the output end of the at least one multiplexer is connected with the main controller; The main controller is configured to acquire a voltage difference between a target gate line and a target read line when each input end of the multiplexer is sequentially selected by the output end, and determine a forward voltage drop of a target temperature sensing device under a preset conduction current; wherein the target gate line is the gate line receiving the preset conduction current provided by the main controller, the target read line is the read line connected with the input end selected by the output end, and the target temperature sensing device is the temperature sensing device connected with the target gate line and the target read line respectively.

4. The display device according to claim 1, wherein The non-display area comprises a first sub-area, a second sub-area, a third sub-area and a fourth sub-area; The first sub-area and the second sub-area are respectively located on two sides of the display area away from each other in a first direction, and the third sub-area and the fourth sub-area are respectively located on two sides of the display area away from each other in a second direction; wherein the first direction and the second direction intersect. The plurality of temperature sensing devices comprises a first temperature sensing device array, a second temperature sensing device array, a third temperature sensing device array and a fourth temperature sensing device array, the first temperature sensing device array is located in the first sub-region, the second temperature sensing device array is located in the second sub-region, the third temperature sensing device array is located in the third sub-region, and the fourth temperature sensing device array is located in the fourth sub-region. The temperature sensing devices in the first temperature sensing device array and the second temperature sensing device array are arranged in an M×N array along the first direction and the second direction. The temperature sensing devices in the third temperature sensing device array and the fourth temperature sensing device array are arranged in an N×M array along the first direction and the second direction. Wherein, M and N are positive integers.

5. The display device according to claim 4, wherein The number of temperature sensing devices is not more than 128.

6. The display device according to claim 1, wherein The temperature sensing device comprises a diode and a bipolar transistor.

7. The display device according to claim 1, wherein The ion doping concentration C of the P-type doped region and the N-type doped region in the PN junction satisfies: C≥1×10 18 cm -3 .

8. The display device according to claim 1, wherein The display panel further comprises a substrate, a driving circuit layer, an insulating layer and a temperature sensing device layer; The driving circuit layer, the insulating layer and the temperature sensing device layer are sequentially stacked in a direction perpendicular to and away from the substrate; 9. The display device according to claim 8, wherein The temperature sensing device layer comprises a semiconductor layer and an electrode layer; The semiconductor layer comprises a plurality of device regions, the device regions comprising intrinsic isolation regions, P-type doped regions and N-type doped regions; the P-type doped regions and the N-type doped regions are respectively located on two sides of the intrinsic isolation regions away from each other in a direction parallel to the substrate; the semiconductor layer of the P-type doped region is doped with an acceptor element, and the semiconductor layer of the N-type doped region is doped with a donor element; the semiconductor layer of the intrinsic isolation region, the P-type doped region and the N-type doped region constitutes a temperature sensing device; The electrode layer comprises an anode and a cathode, the anode covers a side surface of the semiconductor layer of the P-type doped region away from the driving circuit layer, and the cathode covers a side surface of the semiconductor layer of the N-type doped region away from the driving circuit layer.

10. The display device according to claim 9, wherein The semiconductor layer further comprises a shallow trench isolation region, the shallow trench isolation region is located between adjacent device regions in a direction parallel to the substrate.

11. The display device according to claim 9, wherein The thickness of the driving circuit layer ranges from 0.2 to 0.5 μm, and / or the thickness of the insulating layer ranges from 0.3 to 1.5 μm, and / or the thickness of the semiconductor layer ranges from 0.1 to 0.5 μm.

12. The display device of claim 9, wherein, The size of the device region ranges from or equal to 20 μm×20 μm, and the distance between adjacent device regions is not less than 1 mm.

13. The display device of claim 1, wherein The display panel further comprises a front-end circuit, the front-end circuit comprising a differential amplification circuit and an analog-to-digital conversion circuit; the front-end circuit is connected between the temperature sensing device and the main controller; The differential amplification circuit is connected across the PN junction in the temperature sensing device, for amplifying the forward voltage across the PN junction and outputting; The analog-to-digital conversion circuit is connected with the differential amplification circuit, for converting the amplified forward voltage from an analog signal to a digital signal and providing to the main controller.

14. The display device of claim 13, wherein, The front-end circuit further comprises an electrostatic protection circuit and a low-pass filter circuit; The electrostatic protection circuit and the low-pass filter circuit are connected in sequence between the temperature sensing device and the differential amplification circuit.

15. The display device of claim 13, wherein, The display panel further comprises a driving chip, and the front-end circuit is integrated in the driving chip. The display device further comprises I 2 C bus, the temperature sensing device is connected with the driving chip, the driving chip is connected with the main controller through the I 2 C bus.

16. The display device of claim 15, wherein, The display panel further comprises a plurality of light emitting devices, and the light emitting devices are located in the display area. The driving chip further integrates a gate driving circuit and a source driving circuit, and the light emitting devices are connected with the gate driving circuit and the source driving circuit respectively.

17. The display device of claim 1, wherein The display panel further comprises a plurality of light emitting devices, and the light emitting devices are located in the display area; the light emitting devices are connected with the main controller. The driving process of the display device comprises a plurality of display frames, and each display frame comprises a display stage and a temperature sensing stage, and the temperature sensing stage is located after the display stage. The main controller is further configured to: In the display stage, the light emitting devices are driven to display according to a preset driving voltage corresponding to a current display frame. In the temperature sensing stage, a preset conduction current is provided to the temperature sensing device to obtain a forward voltage drop of the PN junction under the preset conduction current, and a temperature of a position where the temperature sensing device is located is determined according to the forward voltage drop.

18. The display device of claim 17, wherein, The display frame further comprises a compensation calculation stage, and the compensation calculation stage is located after the temperature sensing stage. The main controller is further configured to: In the compensation calculation stage, a preset driving voltage corresponding to the light emitting devices adjacent to the temperature sensing device in a next display frame is corrected according to the temperature of the position where the temperature sensing device is located.

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