Light-emitting device

Abstract

According to the light-emitting device, each light sensing unit comprises a temperature compensation transistor and a light sensing transistor, a light shielding layer is arranged on the side, close to the light emitting side of the light-emitting unit, of the temperature compensation transistor, and the vertical projection of the light shielding layer on a film layer where the temperature compensation transistor is located covers the temperature compensation transistor; the output end of the temperature compensation transistor and the output end of the photosensitive transistor are connected with the first end and the second end of the signal processing unit respectively, the output end of the signal processing unit is connected with the control unit, and the signal processing unit is used for processing signals output by the temperature compensation transistor to obtain first signals. Processing the signal output by the photosensitive transistor to obtain a second signal; the control unit is used for determining the ambient brightness according to the first signal and the second signal of each photosensitive unit and adjusting the light emitting brightness of the light emitting unit according to the ambient brightness. The ambient brightness measurement precision of the light sensing unit can be improved, and the brightness adjustment precision of the light emitting device can be improved.

Description

Technical Field

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

[0002] Existing light-emitting devices usually have a photosensitive element on the light-emitting side to measure the ambient brightness through the photosensitive element, so as to adjust the light-emitting brightness of the light-emitting device in real time according to the ambient brightness, thereby reducing power consumption, protecting eyes, and extending the life of the device.

[0003] However, the existing photosensitive elements have low measurement accuracy, which affects the brightness adjustment accuracy of the light-emitting device. Summary of the invention

[0004] The present invention provides a light emitting device to improve the ambient brightness measurement accuracy of a photosensitive unit and to improve the light emitting brightness adjustment accuracy of the light emitting device.

[0005] According to one aspect of the present invention, there is provided a light emitting device, comprising:

[0006] A control unit, a signal processing unit, at least one light emitting unit and at least two light sensing units;

[0007] Each of the photosensitive units comprises a temperature compensation transistor and a photosensitive transistor, a light shielding layer is provided on a side of the temperature compensation transistor adjacent to the light emitting side of the light emitting unit, and a vertical projection of the light shielding layer on the film layer where the temperature compensation transistor is located covers the temperature compensation transistor;

[0008] The output end of the temperature compensation transistor is electrically connected to the first end of the signal processing unit, and the output end of the photosensitive transistor is electrically connected to the second end of the signal processing unit;

[0009] The output end of the signal processing unit is electrically connected to the control unit, and the signal processing unit is used to process the signal output by the temperature compensation transistor to obtain a first signal, process the signal output by the photosensitive transistor to obtain a second signal, and send the first signal and the second signal to the control unit;

[0010] The control unit is used to determine the ambient brightness according to the first signal and the second signal of each of the photosensitive units, and adjust the light emitting brightness of the light emitting unit according to the ambient brightness.

[0011] Optionally, the gate of the temperature compensation transistor and the gate of the photosensitive transistor are both electrically connected to the first output terminal of the control unit, the first electrode of the temperature compensation transistor and the first electrode of the photosensitive transistor are both electrically connected to the second output terminal of the control unit, the second electrode of the temperature compensation transistor and the second electrode of the photosensitive transistor are both electrically connected to the signal processing unit, and the signal processing unit is used to perform signal demodulation, amplification, voltage stabilization and analog-to-digital conversion processing on the signal output by the temperature compensation transistor to obtain the first signal, and perform signal demodulation, amplification, voltage stabilization and analog-to-digital conversion processing on the signal output by the photosensitive transistor to obtain the second signal; or,

[0012] The gate and the second electrode of each temperature compensating transistor are electrically connected to the signal processing unit, and the gate and the second electrode of each photosensitive transistor are electrically connected to the signal processing unit. The first electrode of the temperature compensating transistor and the first electrode of the photosensitive transistor are both electrically connected to the second output end of the control unit. The signal processing unit is used to demodulate, amplify and perform analog-to-digital conversion on the signal output by the temperature compensating transistor to obtain the first signal, and to demodulate, amplify and perform analog-to-digital conversion on the signal output by the photosensitive transistor to obtain the second signal.

[0013] Optionally, when the gate of the temperature compensation transistor and the gate of the photosensitive transistor are both electrically connected to the first output terminal of the control unit, and the first electrode of the temperature compensation transistor and the first electrode of the photosensitive transistor are both electrically connected to the second output terminal of the control unit:

[0014] The signal processing unit includes a plurality of first signal processing sub-units; the plurality of first signal processing sub-units correspond to the temperature compensation transistors and the photosensitive transistors one by one; the second electrode of each temperature compensation transistor is electrically connected to the input end of a first signal processing sub-unit, the second electrode of each photosensitive transistor is electrically connected to the input end of a first signal processing sub-unit, and the output end of each first signal processing sub-unit is electrically connected to the control unit;

[0015] Each of the first signal processing subunits includes a signal demodulation amplifier, a voltage follower and an analog-to-digital converter, wherein the input end of the signal demodulation amplifier is electrically connected to the temperature compensation transistor or the photosensitive transistor, the output end of the signal demodulation amplifier is electrically connected to the input end of the voltage follower, the output end of the voltage follower is electrically connected to the input end of the analog-to-digital converter, and the output end of the analog-to-digital converter is electrically connected to the control unit;

[0016] The signal demodulation amplifier is used to convert the current signal output by the temperature compensation transistor or the photosensitive transistor into an amplified voltage signal, and transmit the amplified voltage signal to the voltage follower.

[0017] Optionally, when the gate and the second electrode of each temperature compensation transistor are electrically connected to the signal processing unit, and the gate and the second electrode of each photosensitive transistor are electrically connected to the signal processing unit:

[0018] The signal processing unit includes a plurality of second signal processing sub-units; the plurality of second signal processing sub-units correspond one to one with the temperature compensation transistor and the photosensitive transistor;

[0019] The gate and the second electrode of each temperature compensation transistor are electrically connected to the input end of a second signal processing subunit, the gate and the second electrode of each photosensitive transistor are electrically connected to the input end of a second signal processing subunit, and the output end of each second signal processing subunit is electrically connected to the control unit;

[0020] The first electrodes of the temperature compensation transistor and the photosensitive transistor are both electrically connected to the second output terminal of the control unit;

[0021] Each of the second signal processing subunits includes a signal demodulation amplifier and an analog-to-digital converter; the input end of the signal demodulation amplifier is electrically connected to the temperature compensation transistor or the photosensitive transistor, the output end of the signal demodulation amplifier is electrically connected to the input end of the analog-to-digital converter, and the output end of the analog-to-digital converter is electrically connected to the control unit;

[0022] The signal demodulation amplifier is used to convert the current signal output by the temperature compensation transistor or the photosensitive transistor into an amplified voltage signal, and transmit the amplified voltage signal to the analog-to-digital converter.

[0023] Optionally, the temperature compensation transistor and the photosensitive transistor are arranged in the same layer, and use the same material and size.

[0024] Optionally, the control unit is used to determine the ambient brightness according to the difference between the second signal and the first signal of each photosensitive unit.

[0025] Optionally, the light emitting device further comprises:

[0026] A driving circuit layer, the driving circuit layer is arranged on the non-light emitting side of the light emitting unit;

[0027] The driving circuit layer includes transistors, and the temperature compensation transistor and the photosensitive transistor are arranged in the same layer as the transistors and are made of the same material.

[0028] Optionally, materials used for the temperature compensation transistor, the photosensitive transistor and the active layer of the transistor include amorphous silicon, low-temperature polysilicon or indium gallium zinc oxide.

[0029] Optionally, the photosensitive unit, the control unit and the signal processing unit are all disposed in a border area of ​​the light-emitting device, and the at least two photosensitive units are evenly arranged along the border area.

[0030] Optionally, the light-emitting unit is an OLED light-emitting unit, an LED light-emitting unit or a liquid crystal light-emitting unit.

[0031] In the embodiment of the present invention, each photosensitive unit includes a temperature compensation transistor and a photosensitive transistor. A light shielding layer is provided on one side of the temperature compensation transistor adjacent to the light output side of the light emitting unit, and the light shielding layer covers the temperature compensation transistor in the vertical projection of the film layer where the temperature compensation transistor is located; the signal processing unit is used to process the signal output by the temperature compensation transistor to obtain a first signal, and to process the signal output by the photosensitive transistor to obtain a second signal. The control unit is used to determine the ambient brightness according to the first signal and the second signal of each photosensitive unit, and adjust the luminous brightness of the light emitting unit according to the ambient brightness. By setting at least two photosensitive units, it is possible to avoid inaccurate ambient brightness measurement caused by some photosensitive units being blocked, thereby improving the measurement accuracy. In addition, by setting each photosensitive unit to include a temperature compensation transistor and a photosensitive transistor, and performing temperature compensation on the second signal of the photosensitive transistor according to the first signal of the temperature compensation transistor, the influence of temperature on the signal output by the photosensitive transistor is removed, thereby improving the detection accuracy of the ambient brightness and the adjustment accuracy of the luminous brightness of the light emitting unit.

[0032] It should be understood that the contents described in this section are not intended to identify the key or important features of the embodiments of the present invention, nor are they intended to limit the scope of the present invention. Other features of the present invention will become easily understood through the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0034] Figure 1 is a structural schematic diagram of a light emitting device provided by an embodiment of the present invention;

[0035] Figure 2 is a module schematic diagram of a light emitting device provided by an embodiment of the present invention;

[0036] Figure 3 is a module diagram of another light emitting device provided by an embodiment of the present invention;

[0037] Figure 4is a module diagram of another light emitting device provided by an embodiment of the present invention;

[0038] Figure 5 is a current curve diagram of the transistor provided by an embodiment of the present invention when Vgs=0;

[0039] Figure 6 is a current curve diagram of the transistor provided by an embodiment of the present invention when Vg<0;

[0040] Figure 7 It is a schematic diagram of a film layer of a temperature compensation transistor and a photosensitive transistor provided by an embodiment of the present invention;

[0041] Figure 8 yes Figure 1 A cross-sectional view of the light emitting device along the section line AA;

[0042] Fig. 9 is a schematic diagram of another light-emitting device provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0043] In order to enable those skilled in the art to better understand the scheme of the present invention, the technical scheme in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present invention.

[0044] It should be noted that the terms "first", "second", etc. in the specification and claims of the present invention and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the data used in this way can be interchanged where appropriate, so that the embodiments of the present invention described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions, for example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units that are clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0045] It is understandable that the application directions of the light-emitting device include but are not limited to display, lighting, phototherapy and other fields. When applied to the display field, the working power of the light-emitting device is large, and the temperature inside the screen body increases, causing the photosensitive element to work in a higher temperature environment, resulting in reduced detection accuracy of the ambient brightness. Similarly, when applied to the field of phototherapy, the light-emitting side of the light-emitting device is close to the human skin. The heat generated by the light-emitting device and the heat generated by the human body receiving phototherapy can both cause the temperature of the light-emitting device to increase, thereby affecting the photosensitivity of the photosensitive element. In addition, since the light wavelength, light energy density and irradiation time used for phototherapy of different human skin are different, the working temperature of the light-emitting device is different. It can be seen that the influence of temperature on photosensitivity in the field of phototherapy is a dynamic process. Therefore, how to filter out the influence of temperature in the process of detecting ambient light brightness when adjusting the brightness of the light-emitting device is an urgent problem to be solved.

[0046] An embodiment of the present invention provides a light emitting device, Figure 1 is a structural schematic diagram of a light emitting device provided by an embodiment of the present invention, Figure 2 is a schematic diagram of a module of a light emitting device provided by an embodiment of the present invention, with reference to Figure 1 and Figure 2 , the light emitting device comprises:

[0047] A control unit 10, a signal processing unit 20, at least one light emitting unit 30 and at least two light sensing units 40;

[0048] Each photosensitive unit 40 includes a temperature compensation transistor 41 and a photosensitive transistor 42. A light shielding layer 50 is disposed on one side of the temperature compensation transistor 41 adjacent to the light emitting side of the light emitting unit 30. The vertical projection of the light shielding layer 50 on the film layer where the temperature compensation transistor 41 is located covers the temperature compensation transistor 41.

[0049] The output end of the temperature compensation transistor 41 is electrically connected to the first end of the signal processing unit 20, and the output end of the light sensing transistor 42 is electrically connected to the second end of the signal processing unit 20;

[0050] The output end of the signal processing unit 20 is electrically connected to the control unit 10. The signal processing unit 20 is used to process the signal output by the temperature compensation transistor 41 to obtain a first signal, process the signal output by the photosensitive transistor 42 to obtain a second signal, and send the first signal and the second signal to the control unit 10;

[0051] The control unit 10 is used to determine the ambient brightness according to the first signal and the second signal of each photosensitive unit 40, and adjust the light emitting brightness of the light emitting unit 30 according to the ambient brightness.

[0052] Wherein, the light-emitting device may include a light-emitting area and a non-light-emitting area, the light-emitting area is used for emitting light, and the area where at least one light-emitting unit 30 is located is the light-emitting area. The non-light-emitting area includes a border area surrounding the light-emitting area. Optionally, the light-emitting unit is an OLED light-emitting unit, an LED light-emitting unit, or a liquid crystal light-emitting unit. The control unit 10 may be a driving chip or a driving circuit. When the light-emitting unit 30 is an OLED light-emitting unit or an LED light-emitting unit, the control unit 10 adjusts the light-emitting brightness of the light-emitting unit 30 according to the ambient brightness, which may be that the control unit 10 adjusts the size of the driving signal output to the light-emitting unit 30, thereby adjusting the light-emitting brightness of the light-emitting unit 30. When the light-emitting unit 30 is an LCD, the control unit 10 adjusts the light-emitting brightness of the light-emitting unit 30 according to the ambient brightness, which may be that the control unit 10 adjusts the size of the driving signal output to the light-emitting unit 30 or adjusts the brightness of the backlight unit, thereby adjusting the light-emitting brightness of the light-emitting unit 30.

[0053] The photosensitive transistor 42 and the temperature compensation transistor 41 are the same transistors. When the light intensity irradiated on the photosensitive transistor 42 changes, the output current changes. When the ambient temperature changes, the current signal output by the photosensitive transistor 42 also changes. The temperature compensation transistor 41 is shielded by the light shielding layer 50, and the ambient light cannot irradiate on it. When the ambient temperature changes, the current signal output by the temperature compensation transistor 41 changes. The signal processing unit 20 is used to perform current-to-voltage conversion, amplification, voltage following, and analog-to-digital conversion on the current signals output by the photosensitive transistor 42 and the temperature compensation transistor 41, and transmit the processed first signal and second signal to the control unit 10.

[0054] The control unit 10 performs temperature compensation on the second signal of the photosensitive transistor 42 according to the first signal of the temperature compensation transistor 41, removes the influence of temperature on the signal output by the photosensitive transistor 42, obtains accurate ambient brightness, and accurately adjusts the luminous brightness of the light-emitting unit 10 according to the ambient brightness.

[0055] In the embodiment of the present invention, each photosensitive unit 40 includes a temperature compensation transistor 41 and a photosensitive transistor 42. A light shielding layer 50 is provided on one side of the temperature compensation transistor 41 adjacent to the light output side of the light emitting unit 30. The light shielding layer 50 covers the temperature compensation transistor 50 in the vertical projection of the film layer where the temperature compensation transistor 41 is located; the signal processing unit 20 is used to process the signal output by the temperature compensation transistor 41 to obtain a first signal, and to process the signal output by the photosensitive transistor 42 to obtain a second signal. The control unit 10 is used to determine the ambient brightness according to the first signal and the second signal of each photosensitive unit 40, and adjust the luminous brightness of the light emitting unit 30 according to the ambient brightness. By setting at least two photosensitive units 40, it is possible to avoid inaccurate ambient brightness measurement caused by some photosensitive units 40 being blocked, thereby improving the measurement accuracy. In addition, by setting each photosensitive unit 40 to include a temperature compensation transistor 41 and a photosensitive transistor 42, and performing temperature compensation on the second signal of the photosensitive transistor 42 according to the first signal of the temperature compensation transistor 41, the influence of temperature on the signal output by the photosensitive transistor 42 is removed, the detection accuracy of the ambient brightness is improved, and the adjustment accuracy of the luminous brightness of the light emitting unit 10 is improved.

[0056] Based on the above embodiments, Figure 3 is a module diagram of another light emitting device provided by an embodiment of the present invention, referring to Figure 3 , this embodiment provides a connection method of the temperature compensation transistor 41, the photosensitive transistor 42, the signal processing unit 20 and the control unit 10:

[0057] The gate of the temperature compensation transistor 41 and the gate of the photosensitive transistor 42 are both electrically connected to the first output terminal of the control unit 10, the first electrode of the temperature compensation transistor 41 and the first electrode of the photosensitive transistor 42 are both electrically connected to the second output terminal of the control unit 10, the second electrode of the temperature compensation transistor 41 and the second electrode of the photosensitive transistor 42 are both electrically connected to the signal processing unit 20, and the signal processing unit 20 is used to demodulate, amplify, stabilize the voltage, and perform analog-to-digital conversion processing on the signal output by the temperature compensation transistor 41 to obtain a first signal, and to demodulate, amplify, stabilize the voltage, and perform analog-to-digital conversion processing on the signal output by the photosensitive transistor 42 to obtain a second signal.

[0058] Among them, the first pole of the temperature compensation transistor 41 and the photosensitive transistor 42 is a drain, and the second pole is a source, or the first pole is a source, and the second pole is a drain. The control unit 10 inputs the same signal to the gate of the temperature compensation transistor 41 and the photosensitive transistor 42, and inputs the same signal to the first pole of the temperature compensation transistor 41 and the photosensitive transistor 42. The control unit 10 is used to input a fixed voltage signal to the first pole of the temperature compensation transistor 41 and the photosensitive transistor 42, and exemplarily, a 10V voltage signal is input. When the temperature or ambient brightness changes, the current output by the second pole of the photosensitive transistor 42 changes. When the temperature changes, the current output by the second pole of the temperature compensation transistor 41 changes. Demodulation and amplification means that the signal processing unit 20 demodulates and amplifies the current output by the temperature compensation transistor 41 or the photosensitive unit 42, and demodulation can be to convert the current signal into a voltage signal. The voltage of the second electrode of the temperature compensation transistor 41 and the photosensitive transistor 42 will change with the change of the current output by the second electrode. The signal processing unit 20 stabilizes the voltage of the signal output by the photosensitive transistor 42 and the temperature compensation transistor 41, that is, stabilizes the voltage of the second electrode of the photosensitive transistor 42 and the temperature compensation transistor 41 to prevent the voltage of the second electrode from changing with the change of the current output by the second electrode. Analog-to-digital conversion converts analog signals into digital signals.

[0059] In the embodiment of the present invention, a signal processing unit 20 is provided to perform demodulation, amplification, voltage stabilization and analog-to-digital conversion processing on the signal output by the temperature compensation transistor 41, and to perform signal demodulation, amplification, voltage stabilization and analog-to-digital conversion processing on the signal output by the photosensitive transistor 42, so as to avoid the current change of the temperature compensation transistor 41 and the photosensitive transistor 42 affecting the voltage of the second electrode of the temperature compensation transistor 41 and the photosensitive transistor 42, so that the second signal and the first signal can accurately reflect the current change caused by the change of ambient brightness and ambient temperature, thereby making the ambient brightness determined according to the second signal and the first signal more accurate.

[0060] Optional, continue to refer to Figure 3 The signal processing unit includes a plurality of first signal processing subunits 21; the plurality of first signal processing subunits 21 correspond to the temperature compensation transistors 41 and the photosensitive transistors 42 one by one; the second electrode of each temperature compensation transistor 41 is electrically connected to the input end of a first signal processing subunit 21, the second electrode of each photosensitive transistor 42 is electrically connected to the input end of a first signal processing subunit 21, and the output end of each first signal processing subunit 21 is electrically connected to the control unit 10;

[0061] Each first signal processing subunit 21 includes a signal demodulation amplifier 211, a voltage follower 212 and an analog-to-digital converter 213. The input end of the signal demodulation amplifier 211 is electrically connected to the temperature compensation transistor 41 or the photosensitive transistor 42, the output end of the signal demodulation amplifier 211 is electrically connected to the input end of the voltage follower 212, the output end of the voltage follower 212 is electrically connected to the input end of the analog-to-digital converter 213, and the output end of the analog-to-digital converter 213 is electrically connected to the control unit 10.

[0062] The signal demodulation amplifier 211 is used to convert the current signal output by the temperature compensation transistor 41 or the photosensitive transistor 42 into an amplified voltage signal, and transmit the amplified voltage signal to the voltage follower 212 .

[0063] Specifically, the current signals output by the photosensitive transistor 42 and the temperature compensation transistor 41 are demodulated and amplified, and then input to the control unit 10 after voltage stabilization and digital-to-analog conversion. The control unit 10 performs a difference on the signal, filters out the interference of temperature on the photosensitive transistor 42, and realizes accurate and real-time sensing of ambient brightness by the photosensitive transistor 42. The voltage follower 212 is used to stabilize the voltage of the second pole of the temperature compensation transistor 41 and the photosensitive transistor 42, to prevent the voltage of the second pole of the temperature compensation transistor 41 from changing with the current of the temperature compensation transistor 41, and to prevent the voltage of the second pole of the photosensitive transistor 42 from changing with the current of the photosensitive transistor 42, so as to ensure that the control unit 10 can collect a stable light-sensing voltage.

[0064] The signal demodulation amplifier 21 may include a resistor, one end of which is electrically connected to the second electrode of the temperature compensation transistor 41 (or the photosensitive transistor 42) and the input end of the voltage follower 212, and the other end of the resistor is grounded. The size of the resistor can be adjusted according to the voltage required, and the specific size of the resistor is not specifically limited in this embodiment. The voltage follower 212 may include an operational amplifier, and the output end of the operational amplifier is connected to the inverting input end to form the voltage follower 212.

[0065] Optional, Figure 4 is a module diagram of another light emitting device provided by an embodiment of the present invention, referring to Figure 4 This embodiment provides another connection method of the temperature compensation transistor 41, the photosensitive transistor 42, the signal processing unit 20 and the control unit 10:

[0066] The gate and the second electrode of each temperature compensation transistor 41 are electrically connected to the signal processing unit 20, and the gate and the second electrode of each photosensitive transistor 42 are electrically connected to the signal processing unit 20. The first electrode of the temperature compensation transistor 41 and the first electrode of the photosensitive transistor 42 are both electrically connected to the second output end of the control unit 10. The signal processing unit 20 is used to demodulate, amplify and perform analog-to-digital conversion on the signal output by the temperature compensation transistor 41 to obtain a first signal, and to demodulate, amplify and perform analog-to-digital conversion on the signal output by the photosensitive transistor 42 to obtain a second signal.

[0067] Specifically, the control unit 10 is used to input a fixed voltage signal to the first electrode of the temperature compensation transistor 41 and the photosensitive transistor 42. For example, a 10V voltage signal is input. Figure 4 After the gate and the second electrode of the temperature compensation transistor 41 are electrically connected, the voltage difference Vgs1 between the gate and the second electrode is 0, and the voltage of the second electrode of the temperature compensation transistor 41 does not change with the current of the temperature compensation transistor 41. There is no need to set a voltage follower, which reduces the circuit cost.

[0068] After the gate and the second electrode of the photosensitive transistor 42 are electrically connected, the voltage difference Vgs2 between the gate and the second electrode is 0, and the voltage of the second electrode of the photosensitive transistor 42 does not change with the current of the photosensitive transistor 42. There is no need to set a voltage follower, which reduces the circuit cost.

[0069] Figure 5 is a current curve diagram of the transistor provided by an embodiment of the present invention when Vgs=0, Figure 6 is a current curve diagram of the transistor provided by the embodiment of the present invention when Vg<0. Figure 5 and Figure 6 , under 1940cd light intensity, the drain of the transistor is connected to a 10V voltage, when Vgs=0V, the current output by the transistor is 35nA, when Vgs<0V, the current output by the transistor is 350pA, and the current when Vgs=0V is about 100 times that when Vgs<0V. Therefore, this proposal makes the current output by the temperature compensation transistor and the photosensitive transistor larger by short-circuiting the gate and the second pole of the transistor (Vgs=0V), which can further improve the detection accuracy, and does not need to set a voltage follower, reducing the circuit cost. Figure 7 is a schematic diagram of a film layer of a temperature compensation transistor and a photosensitive transistor provided by an embodiment of the present invention, with reference to Figure 4 and Figure 7The gate 413 and the second electrode 412 of each temperature compensation transistor 41 are electrically connected to the signal processing unit 20, and the gate 423 and the second electrode 422 of each photosensitive transistor 42 are electrically connected to the signal processing unit 20. The first electrode 411 of the temperature compensation transistor 41 and the first electrode 421 of the photosensitive transistor 42 are both electrically connected to the second output terminal of the control unit 10. The first electrode 411 of the temperature compensation transistor 41 and the first electrode 421 of the photosensitive transistor 42 can be comb-shaped, and the second electrode 412 of the temperature compensation transistor 41 and the second electrode 422 of the photosensitive transistor 42 can also be comb-shaped. The comb-shaped electrode has a main body, and a plurality of sub-parts are connected to one side of the main body, and the plurality of sub-parts are arranged in sequence along the extension direction of the main body.

[0070] It should be noted that Figure 7 The active layers of the temperature compensation transistor 41 and the photosensitive transistor 42 are not shown in the figure, and are not a limitation to this embodiment.

[0071] Optional, continue to refer to Figure 4 The signal processing unit 20 includes a plurality of second signal processing sub-units 22; the plurality of second signal processing sub-units 22 correspond one to one with the temperature compensation transistors 41 and the photosensitive transistors 42; the gate and the second pole of each temperature compensation transistor 41 are electrically connected to the input end of a second signal processing sub-unit 22, the gate and the second pole of each photosensitive transistor 42 are electrically connected to the input end of a second signal processing sub-unit 22, and the output end of each second signal processing sub-unit 22 is electrically connected to the control unit 10; the first poles of the temperature compensation transistor 41 and the photosensitive transistor 42 are both electrically connected to the second output end of the control unit 10.

[0072] Each second signal processing subunit 22 includes a signal demodulation amplifier 211 and an analog-to-digital converter 213; the input end of the signal demodulation amplifier 211 is electrically connected to the temperature compensation transistor 41 or the photosensitive transistor 42, the output end of the signal demodulation amplifier 211 is electrically connected to the input end of the analog-to-digital converter 213, and the output end of the analog-to-digital converter 213 is electrically connected to the control unit 10;

[0073] The signal demodulation amplifier 211 is used to convert the current signal output by the temperature compensation transistor 41 or the photosensitive transistor 42 into an amplified voltage signal, and transmit the amplified voltage signal to the analog-to-digital converter 213. Specifically, the signal demodulation amplifier 211 may include a resistor, one end of which is electrically connected to the second electrode of the temperature compensation transistor 41 (or the photosensitive transistor 42) and the input end of the second signal processing subunit 22, and the other end of the resistor is grounded. The size of the resistor can be adjusted according to the voltage required, and the specific size of the resistor is not specifically limited in this embodiment.

[0074] Optional, Figure 8 yes Figure 1 The cross-sectional view of the light emitting device along the section line AA, refer to Figure 7 and Figure 8 The temperature compensation transistor 41 and the photosensitive transistor 42 are arranged in the same layer, and the materials and sizes used are the same.

[0075] That is, the gate 413 of the temperature compensation transistor 41 and the gate 423 of the photosensitive transistor 42 are arranged in the same layer, made of the same material and in the same size, the second electrode 412 (source) of the temperature compensation transistor 41 and the second electrode 412 (source) of the photosensitive transistor 42 are arranged in the same layer, made of the same material and in the same size, the first electrode 411 (drain) of the temperature compensation transistor 41 and the first electrode 421 (drain) of the photosensitive transistor 42 are arranged in the same layer, made of the same material and in the same size, and the active layer of the temperature compensation transistor 41 and the photosensitive transistor 42 are arranged in the same layer, made of the same material and in the same size, that is, the temperature compensation transistor 41 and the photosensitive transistor 42 are the same transistor. In this way, the temperature compensation transistor 41 and the photosensitive transistor 42 can be formed in the same process using the same process, thereby reducing the process steps and the process cost.

[0076] Optionally, the control unit is used to determine the ambient brightness according to the difference between the second signal and the first signal of each photosensitive unit.

[0077] Specifically, the photosensitive transistor 42 and the temperature compensation transistor 41 are the same transistors, and the temperature causes the same current change to the photosensitive transistor 42 and the temperature compensation transistor 41. The current output by the photosensitive transistor 42 is I light + I temperature, and the current output by the temperature compensation transistor 41 is I temperature. The second signal corresponds to I light + I temperature, the first signal corresponds to I temperature, and the difference between the second signal and the first signal corresponds to I light. By making a difference between the second signal and the first signal, the influence of temperature on the photocurrent can be filtered out, and a more accurate ambient brightness can be obtained.

[0078] Optionally, the light emitting device further comprises:

[0079] A driving circuit layer 60 , which is disposed on the non-light-emitting side of the light-emitting unit 30 ;

[0080] The driving circuit layer 60 includes a transistor 61 . The temperature compensation transistor 41 and the photosensitive transistor 42 are arranged in the same layer as the transistor 61 and are made of the same material.

[0081] That is, the gates of the temperature compensation transistor 41 and the photosensitive transistor 42 are arranged in the same layer as the gate of the transistor 61, and are made of the same material; the source of the temperature compensation transistor 41 and the photosensitive transistor 42 are arranged in the same layer as the source of the transistor 61, and are made of the same material; the drain of the temperature compensation transistor 41 and the photosensitive transistor 42 are arranged in the same layer as the drain of the transistor 61, and are made of the same material; the active layer of the temperature compensation transistor 41 and the photosensitive transistor 42 are arranged in the same layer as the active layer of the transistor 61, and are made of the same material. This arrangement enables the temperature compensation transistor 41 and the photosensitive transistor 42 to be prepared in the same process as the transistor 61, thereby reducing the process steps and the process cost.

[0082] Optionally, materials used for the temperature compensation transistor, the photosensitive transistor and the active layer of the transistor include amorphous silicon, low-temperature polysilicon or indium gallium zinc oxide.

[0083] Optional, Fig. 9 is a schematic diagram of another light emitting device provided by an embodiment of the present invention, referring to Fig. 9 The photosensitive unit 40 , the control unit 10 and the signal processing unit 20 are all disposed in the border area 100 of the light emitting device, and at least two photosensitive units 40 are evenly arranged along the border area 100 .

[0084] Specifically, the photosensitive unit 40, the control unit 10 and the signal processing unit 20 are all arranged in the border area 100 of the light-emitting device, so that the photosensitive unit 40, the control unit 10 and the signal processing unit 20 have a large setting space, and can avoid affecting the routing and light emission of the light-emitting unit 30. The two photosensitive units 40 are evenly arranged along the border area 100 so that the photosensitive units 40 can fully detect the ambient brightness at different positions of the light-emitting device, thereby more accurately determining the ambient brightness and more accurately adjusting the light-emitting brightness of the light-emitting unit 30.

[0085] In addition, the border area 100 may include a shift register circuit 70, which is used to transmit a scan signal or a light control signal to the light emitting unit 30. The photosensitive unit 40 may be arranged on a side of the shift register circuit 70 away from the light emitting unit 30, so as to avoid the photosensitive unit 40 affecting the wiring between the shift register circuit 70 and the light emitting unit 30.

[0086] It should be understood that the various forms of processes shown above can be used to reorder, add or delete steps. For example, the steps described in the present invention can be executed in parallel, sequentially or in different orders, as long as the desired results of the technical solution of the present invention can be achieved, and this document does not limit this.

[0087] The above specific implementations do not constitute a limitation on the protection scope of the present invention. It should be understood by those skilled in the art that various modifications, combinations, sub-combinations and substitutions can be made according to design requirements and other factors. Any modification, equivalent substitution and improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A light emitting device, characterized in that: include: A control unit, a signal processing unit, at least one light emitting unit and at least two light sensing units; Each of the photosensitive units comprises a temperature compensation transistor and a photosensitive transistor, a light shielding layer is provided on a side of the temperature compensation transistor adjacent to the light emitting side of the light emitting unit, and a vertical projection of the light shielding layer on the film layer where the temperature compensation transistor is located covers the temperature compensation transistor; The output end of the temperature compensation transistor is electrically connected to the first end of the signal processing unit, and the output end of the photosensitive transistor is electrically connected to the second end of the signal processing unit; The output end of the signal processing unit is electrically connected to the control unit, and the signal processing unit is used to process the signal output by the temperature compensation transistor to obtain a first signal, process the signal output by the photosensitive transistor to obtain a second signal, and send the first signal and the second signal to the control unit; The control unit is used to determine the ambient brightness according to the first signal and the second signal of each of the photosensitive units, and adjust the light emitting brightness of the light emitting unit according to the ambient brightness.

2. The light emitting device according to claim 1, characterized in that: The gate of the temperature compensation transistor and the gate of the photosensitive transistor are both electrically connected to the first output terminal of the control unit, the first electrode of the temperature compensation transistor and the first electrode of the photosensitive transistor are both electrically connected to the second output terminal of the control unit, the second electrode of the temperature compensation transistor and the second electrode of the photosensitive transistor are both electrically connected to the signal processing unit, and the signal processing unit is used to perform signal demodulation, amplification, voltage stabilization and analog-to-digital conversion processing on the signal output by the temperature compensation transistor to obtain the first signal, and perform signal demodulation, amplification, voltage stabilization and analog-to-digital conversion processing on the signal output by the photosensitive transistor to obtain the second signal; or, The gate and the second electrode of each temperature compensating transistor are electrically connected to the signal processing unit, and the gate and the second electrode of each photosensitive transistor are electrically connected to the signal processing unit. The first electrode of the temperature compensating transistor and the first electrode of the photosensitive transistor are both electrically connected to the second output end of the control unit. The signal processing unit is used to demodulate, amplify and perform analog-to-digital conversion on the signal output by the temperature compensating transistor to obtain the first signal, and to demodulate, amplify and perform analog-to-digital conversion on the signal output by the photosensitive transistor to obtain the second signal.

3. The light emitting device according to claim 2, characterized in that: When the gate of the temperature compensation transistor and the gate of the photosensitive transistor are both electrically connected to the first output terminal of the control unit, and the first electrode of the temperature compensation transistor and the first electrode of the photosensitive transistor are both electrically connected to the second output terminal of the control unit: The signal processing unit includes a plurality of first signal processing sub-units; the plurality of first signal processing sub-units correspond to the temperature compensation transistors and the photosensitive transistors one by one; the second electrode of each temperature compensation transistor is electrically connected to the input end of a first signal processing sub-unit, the second electrode of each photosensitive transistor is electrically connected to the input end of a first signal processing sub-unit, and the output end of each first signal processing sub-unit is electrically connected to the control unit; Each of the first signal processing subunits includes a signal demodulation amplifier, a voltage follower and an analog-to-digital converter, wherein the input end of the signal demodulation amplifier is electrically connected to the temperature compensation transistor or the photosensitive transistor, the output end of the signal demodulation amplifier is electrically connected to the input end of the voltage follower, the output end of the voltage follower is electrically connected to the input end of the analog-to-digital converter, and the output end of the analog-to-digital converter is electrically connected to the control unit; The signal demodulation amplifier is used to convert the current signal output by the temperature compensation transistor or the photosensitive transistor into an amplified voltage signal, and transmit the amplified voltage signal to the voltage follower.

4. The light emitting device according to claim 2, characterized in that: When the gate and the second electrode of each temperature compensation transistor are electrically connected to the signal processing unit, and the gate and the second electrode of each photosensitive transistor are electrically connected to the signal processing unit: The signal processing unit includes a plurality of second signal processing sub-units; the plurality of second signal processing sub-units correspond one to one with the temperature compensation transistor and the photosensitive transistor; The gate and the second electrode of each temperature compensation transistor are electrically connected to the input end of a second signal processing subunit, the gate and the second electrode of each photosensitive transistor are electrically connected to the input end of a second signal processing subunit, and the output end of each second signal processing subunit is electrically connected to the control unit; The first electrodes of the temperature compensation transistor and the photosensitive transistor are both electrically connected to the second output terminal of the control unit; Each of the second signal processing subunits includes a signal demodulation amplifier and an analog-to-digital converter; The input end of the signal demodulation amplifier is electrically connected to the temperature compensation transistor or the photosensitive transistor, the output end of the signal demodulation amplifier is electrically connected to the input end of the analog-to-digital converter, and the output end of the analog-to-digital converter is electrically connected to the control unit; The signal demodulation amplifier is used to convert the current signal output by the temperature compensation transistor or the photosensitive transistor into an amplified voltage signal, and transmit the amplified voltage signal to the analog-to-digital converter.

5. The light emitting device according to claim 1, characterized in that: The temperature compensation transistor and the photosensitive transistor are arranged in the same layer and are made of the same material and have the same size.

6. The light emitting device according to claim 5, characterized in that: The control unit is used to determine the ambient brightness according to the difference between the second signal and the first signal of each photosensitive unit.

7. The light emitting device according to claim 1, characterized in that: Also includes: A driving circuit layer, the driving circuit layer is arranged on the non-light emitting side of the light emitting unit; The driving circuit layer includes transistors, and the temperature compensation transistor and the photosensitive transistor are arranged in the same layer as the transistors and are made of the same material.

8. The light emitting device according to claim 7, characterized in that: The materials used for the temperature compensation transistor, the photosensitive transistor and the active layer of the transistor include amorphous silicon, low temperature polysilicon or indium gallium zinc oxide.

9. The light emitting device according to claim 1, characterized in that: The photosensitive unit, the control unit and the signal processing unit are all arranged in a border area of ​​the light emitting device, and the at least two photosensitive units are evenly arranged along the border area.

10. The light emitting device according to claim 1, characterized in that: The light emitting unit is an OLED light emitting unit, an LED light emitting unit or a liquid crystal light emitting unit.

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