Display apparatus, backlight control circuit, and backlight control method

Abstract

A display apparatus (100), a backlight control circuit (120), and a backlight control method. The backlight control circuit (120) includes a power supply circuit (121), a local dimming circuit (122), a backlight driving circuit (123), and a power voltage adjustment circuit (124), wherein the power supply circuit (121) is used for outputting a power voltage (VLED) to a backlight module (LD), the backlight module (LD) has a plurality of dimming partitions (LDa), and each dimming partition (LDa) is provided with a plurality of light-emitting diodes; the local dimming circuit (122) is used for generating a local dimming signal (SLD) on the basis of image data and configurations of these dimming partitions (LDa); the backlight driving circuit (123) is used for generating, on the basis of the local dimming signal (SLD), a plurality of backlight driving signals (SBD) for these dimming partitions (LDa) of the backlight module (LD); and the power voltage adjustment circuit (124) is used for generating, on the basis of the local dimming signal (SLD) and characteristic data of each light-emitting diode in these dimming partitions (LDa), a first power voltage adjustment signal (V1) for the power supply circuit (121), so as to adjust the power voltage (VLED).

Description

Display device, backlight control circuit and backlight control method

[0001] This application claims priority to Chinese patent application number 202311427639.3, filed on October 31, 2023, entitled “Backlight control circuit, display device and backlight control method”, the entire contents of which are hereby incorporated by reference into this application. Technical Field

[0002] The present disclosure relates to a display device, a backlight control circuit, and a backlight control method, and more particularly to a display device, a backlight control circuit, and a backlight control method having a feedforward operating voltage regulation mechanism. Background Art

[0003] In conventional display devices, the backlight system is used to provide the backlight source required by the display panel, so that the display panel can display a frame image based on the backlight source. For a display device with a local dimming function, the backlight system includes a backlight module, a power supply circuit, a backlight driving circuit, and a local dimming circuit. When the display panel wants to display a frame image, the power supply circuit provides the operating voltage required by the backlight module, and adjusts the backlight driving signal of the backlight driving circuit by the local dimming signal of the local dimming circuit, so that the backlight driving circuit can change the current value flowing through the backlight module, thereby adjusting the brightness of the backlight module. Some backlight systems also include a feedback mechanism, which adjusts the operating voltage and driving current accordingly by monitoring the actual brightness of the backlight module to ensure that the brightness of the backlight module always matches the required value, providing a more stable display effect.

[0004] However, the adjustment of operating voltage and drive current depends on the response speed of the feedback circuit and the backlight driver circuit. If the backlight driver circuit's response speed is slow, the process of providing drive current to the backlight module will be slower, which in turn affects the feedback circuit's control timing, making it take longer for the drive current to stabilize, resulting in greater power loss. Alternatively, if the image changes rapidly, using the feedback mechanism to dynamically adjust the operating voltage may result in insufficient real-time tracking of the operating voltage.

[0005] Summary of the Invention

[0006] The present invention provides a backlight control circuit comprising a power supply circuit, a local dimming circuit, a backlight driver circuit, and a supply voltage adjustment circuit. The power supply circuit is configured to output a supply voltage to a backlight module having multiple dimming zones, each of which has multiple light-emitting diodes. The local dimming circuit is configured to generate local dimming signals based on image data and the configuration of the dimming zones. The backlight driver circuit is configured to generate multiple backlight driver signals to the dimming zones of the backlight module based on the local dimming signals. The supply voltage adjustment circuit is configured to generate a first supply voltage adjustment signal to the power supply circuit based on the local dimming signals and characteristic data of each light-emitting diode in the dimming zones to adjust the supply voltage.

[0007] According to an embodiment of the present disclosure, the local dimming signal includes a plurality of brightness values ​​corresponding to the dimming zones under the image data, and the brightness values ​​are provided to the backlight driving circuit to generate the corresponding backlight driving signals.

[0008] According to an embodiment of the present disclosure, each backlight driving signal is a current driving signal, and the characteristic data includes corresponding relationship data between the operating voltage and the operating current of each light-emitting diode in the dimming zones.

[0009] According to an embodiment of the present disclosure, the supply voltage adjustment circuit is further configured to generate a second supply voltage adjustment signal to the power supply circuit according to the detection signal of each LED in the dimming zones to adjust the supply voltage when the supply voltage exceeds a voltage range corresponding to the image data.

[0010] According to an embodiment of the present disclosure, the power supply circuit includes an analog regulation circuit for reducing the supply voltage when the second supply voltage adjustment signal increases, and increasing the supply voltage when the second supply voltage adjustment signal decreases.

[0011] According to an embodiment of the present disclosure, the detection signal is the cathode voltage of each light emitting diode.

[0012] According to an embodiment of the present disclosure, the detection signal is generated by the backlight driving circuit detecting the cathode voltage of each light emitting diode.

[0013] The present invention further provides a display device comprising a display panel, a backlight module, a power supply circuit, a regional dimming circuit, a backlight driving circuit, and a power supply voltage adjustment circuit. The display panel is used to display a frame image based on image data. The backlight module is used to provide a backlight source for the display panel, and the backlight module includes a plurality of dimming zones, and each dimming zone has a plurality of light-emitting diodes. The power supply circuit is used to output a supply voltage to the backlight module. The regional dimming circuit is used to generate a regional dimming signal based on the image data and the configuration of these dimming zones in the backlight module. The backlight driving circuit is used to generate these backlight driving signals based on the regional dimming signal. The power supply voltage adjustment circuit is used to generate a supply voltage adjustment signal to the power supply circuit based on the regional dimming signal and the characteristic data of each light-emitting diode in these dimming zones to adjust the supply voltage.

[0014] According to an embodiment of the present disclosure, the power supply circuit is configured to adjust the supply voltage according to the supply voltage adjustment signal before the display panel displays a frame image.

[0015] According to an embodiment of the present disclosure, each backlight driving signal is a current driving signal, and the characteristic data includes corresponding relationship data between the operating voltage and the operating current of each light-emitting diode in the dimming zones.

[0016] The present invention further provides a backlight control method, comprising: providing a power supply voltage to a backlight module; generating a local dimming signal based on image data and the configuration of multiple dimming zones in the backlight module, wherein each dimming zone has multiple light-emitting diodes; generating multiple backlight driving signals to these dimming zones of the backlight module based on the local dimming signal; generating a first power supply voltage adjustment signal based on the local dimming signal and characteristic data of each light-emitting diode in these dimming zones; and adjusting the power supply voltage based on the first power supply voltage adjustment signal.

[0017] According to an embodiment of the present disclosure, the supply voltage is adjusted according to the first supply voltage adjustment signal before the display panel provided with backlight by the backlight module displays a frame image based on image data.

[0018] According to an embodiment of the present disclosure, each backlight driving signal is a current driving signal, and the characteristic data includes corresponding relationship data between the operating voltage and the operating current of each light-emitting diode in the dimming zones.

[0019] According to an embodiment of the present disclosure, the backlight control method further includes: generating a second supply voltage adjustment signal according to the detection signal of each LED in the dimming zones when the supply voltage exceeds a voltage range corresponding to the image data; and adjusting the supply voltage according to the second supply voltage adjustment signal.

[0020] According to an embodiment of the present disclosure, adjusting the supply voltage according to the second supply voltage adjustment signal includes: reducing the supply voltage when the second supply voltage adjustment signal increases, and increasing the supply voltage when the second supply voltage adjustment signal decreases.

[0021] According to an embodiment of the present disclosure, the detection signal is the cathode voltage of each light emitting diode.

[0022] According to an embodiment of the present disclosure, the backlight control method further includes: detecting the cathode voltage of each light emitting diode to generate a detection signal. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] In order to make the above and other objects, features, advantages and embodiments of the present invention more easily understood, the accompanying drawings are now described as follows:

[0024] FIG1 is a schematic diagram of a display device according to an embodiment of the present invention;

[0025] 2 is a schematic diagram of a backlight control circuit and a backlight module of a display device according to an embodiment of the present invention;

[0026] FIG3 is a schematic diagram illustrating characteristic data according to an embodiment of the present invention;

[0027] 4 is a schematic diagram of a backlight control circuit and a backlight module of a display device according to an embodiment of the present invention;

[0028] FIG5 is a schematic diagram of a control timing according to an embodiment of the present invention; and

[0029] FIG. 6 is a flow chart of a backlight control method according to an embodiment of the present invention. DETAILED DESCRIPTION

[0030] Referring to Figure 1, the display device 100 includes a display panel 110 and a backlight control circuit 120. The display panel 110 can be, for example, a twisted nematic (TN) display panel, a vertical alignment (VA) display panel, an in-plane switching (IPS) display panel, or other suitable types of display panels. The backlight control circuit 120 is used to control the backlight module LD to provide the display panel 110 with the backlight required for image display, and the backlight module LD can be a direct-type backlight module, which is arranged on the back side of the display panel 110. The backlight control circuit 120 can implement local dimming of the backlight module LD according to the image data, so that different display areas on the display panel 110 can display different brightness according to the backlight provided by the backlight module LD.

[0031] 2 , the backlight module LD has a plurality of dimming zones LDa, and each dimming zone LDa may have a plurality of light-emitting diodes. The backlight control circuit 120 includes a power supply circuit 121, a local dimming circuit 122, a backlight driving circuit 123, and a supply voltage adjustment circuit 124. The power supply circuit 121 is electrically connected to the backlight module LD and is used to output a supply voltage V LED To the backlight module LD, to provide the total operating voltage V required by the light-emitting diodes in each dimming zone LDa X The local dimming circuit 122 is used to receive image data and generate a local dimming signal S according to the image data and the configuration of the dimming zones LDa. LD The backlight driving circuit 123 is electrically connected to the backlight module LD and the local dimming circuit 122 and is used to receive the local dimming signal S LD , and generates the corresponding backlight driving signal S BD The power supply voltage adjustment circuit 124 is electrically connected to the power supply circuit 121 and the local dimming circuit 122 and is used to adjust the power supply voltage according to the local dimming signal S LD The characteristic data of each light emitting diode in each dimming zone LDa is used to generate a first power supply voltage adjustment signal V1 to adjust the power supply voltage V required by the backlight module LD for the next frame image in advance. LED In this way, the backlight control circuit 120 can adjust the brightness of the backlight according to the regional dimming signal S LD And the characteristic data of each light emitting diode in these dimming partitions LDa, the supply voltage V LED Adjust to an appropriate value to generate the modulated supply voltage V LED , and then sent to the backlight module LD. This sends the first supply voltage adjustment signal V1 to the power supply circuit 121 so that the power supply circuit 121 pre-modulates the supply voltage V output to the backlight module LD according to the first supply voltage adjustment signal V1. LED The power supply voltage V LED Real-time regulation is performed to speed up the stabilization of the driving current required by each dimming zone LDa, thereby improving transient response and light board power consumption, and effectively reducing power loss.

[0032] In some embodiments, as shown in FIG2 , the LEDs in each dimming zone LDa are connected in series so that the current flowing through the LEDs is consistent and the brightness emitted is also approximately the same. If one dimming zone LDa has N LEDs connected in series, the operating voltage required for each LED is V F , represents the total operating voltage V required for the dimming partition LDa XAt least N×V F Therefore, the power supply circuit 121 supplies the power supply voltage V to the dimming subarea LDa. LED Need to be greater than the total operating voltage V X , to light up the dimming subarea LDa. On the contrary, if the power supply circuit 121 supplies the power supply voltage V LED Less than the total operating voltage V X , then the dimming zone LDa cannot be lit.

[0033] The power supply circuit 121 can be a linear power supply or a switching power supply, and the power supply circuit 121 outputs a power supply voltage V LED Feedback control may be implemented in an analog or digital manner, but the present invention is not limited thereto.

[0034] Local dimming signal S LD The dimming subarea LDa includes the corresponding brightness values ​​(dim level) under the image data, and these corresponding brightness values ​​can be used by the backlight driving circuit 123 to generate the corresponding backlight driving signal S BD . Backlight drive signal S BD It can be a current drive signal, which is used to control the current value flowing through these light-emitting diodes in each dimming zone LDa. Then, based on the information of the LED driver IC corresponding to each dimming zone LDa, the current required by the channel of the LED driver IC is obtained, and each dimming zone LDa produces corresponding luminous brightness.

[0035] The characteristic data includes the operating voltage V of each light-emitting diode in each dimming zone LDa F The characteristic data can be pre-built in the power supply voltage adjustment circuit 124 so as to receive the local dimming signal S LD When the power supply voltage adjustment circuit 124 can immediately calculate the basic power supply voltage V required to light up these dimming zones LDa, LED , and generates a first supply voltage adjustment signal V1 to the power supply circuit 121 to adjust the supply voltage V in advance. LED Adjust to an appropriate value. In other words, it is to control the output voltage of DC / DC (Power Supply), and finally make the voltage V LED Control within a reasonable range to achieve the advantage of faster real-time regulation.

[0036] The brightness value required by the dimming partition LDa and the operating current I Fis proportional to the working current I F The operating voltage is in the range of 1 mA to 100 mA. F With the working current I F Therefore, when the power supply voltage adjustment circuit 124 adjusts the power supply voltage according to the local dimming signal S LD After obtaining the required brightness value of each dimming zone LDa (which also represents the current value flowing through it), the operating current I of each light-emitting diode in the characteristic data can be calculated in advance. F Find the required operating voltage V for each LED F , and then predict in advance the basic power supply voltage V required for the dimming partition LDa LED In this way, the supply voltage V LED Adjust to an appropriate value to speed up the stabilization of the driving current required by each dimming zone LDa and effectively reduce power loss.

[0037] In this embodiment, the power supply circuit 121 further includes an analog regulation circuit. As shown in FIG4 , when the power supply voltage V adjusted by the first power supply voltage adjustment signal V1 is LED When the voltage range of the corresponding image data is exceeded, the supply voltage adjustment circuit 124 can adjust the voltage according to the detection signal V of each light emitting diode in the dimming zone LDa. D Generates a second supply voltage adjustment signal V2 to the analog regulation circuit of the power supply circuit 121 to fine-tune the supply voltage V LED Detection signal V D This can be the cathode voltage of each LED, or an adjustment signal generated by the backlight driver circuit 123 after detecting the cathode voltage of each LED. This allows for dynamic adjustment based on the actual voltage range, a form of post-modulation of the supply voltage to improve transient response, ensuring stable and safe operation of each dimming zone LDa of the backlight module LD, and enhancing the stability and reliability of the driver power supply.

[0038] Specifically, when the potential of the second supply voltage adjustment signal V2 rises, the power supply circuit 121 reduces the supply voltage V LED When the potential of the second supply voltage adjustment signal V2 drops, the power supply circuit 121 increases the supply voltage V LED Thus, the second supply voltage adjustment signal V2 is used as the adjustment voltage of the feedback mechanism to adjust the supply voltage V LED Fine-tune to the required value to ensure that the actual operating voltage of each dimming zone LDa of the backlight module LD meets the default voltage or falls within the voltage range of the corresponding image data.

[0039] In this embodiment, the backlight control circuit 120 further includes a timing controller for controlling the backlight module LD according to the timing instructions of the backlight control circuit 120. Referring to FIG. 5 , the timing controller generates a vertical synchronization signal V sync , so that the local dimming circuit 122 and the backlight driving circuit 123 complete the local dimming signal S within one frame period. LD The calculation (during the period from time point t0 to time point t1) and the backlight driving signal S BD transmission (during the period from time point t1 to time point t2), and in the vertical synchronization signal V sync The next pulse signal of the display frame image. At time point t1, the local dimming signal S LD The calculation is completed, indicating that the local dimming signal S LD and the characteristic data of each light emitting diode in each dimming zone LDa, the power supply voltage adjustment circuit 124 can generate a first power supply voltage adjustment signal V1 at time point t1 and adjust the power supply voltage V LED In addition, at time point t2, the power supply voltage adjustment circuit 124 can adjust the power supply voltage according to the detection signal V of each light emitting diode in the dimming partition LDa. D Generates a second supply voltage adjustment signal V2 to fine-tune the supply voltage V LED .

[0040] For example, the local dimming circuit 122 generates the corresponding backlight driving signals S according to the multiple brightness levels corresponding to the image data during the time from the completion of image reception to the start of image display. BD Therefore, the corresponding backlight driving signals S can be generated when the image changes rapidly. BD At a 60Hz frame rate, the time from image reception completion to image display start is approximately 16.6 milliseconds (ms). The backlight driving circuit 123 can then output these backlight driving signals S BD .

[0041] In some embodiments, the total operating voltage V required for each dimming zone LDa is X The configuration of the light emitting diodes may vary, so the power supply circuit 121 may also supply the same (eg, shared) or different supply voltages V as required. LED To each dimming zone LDa. For example, the power supply circuit 121 can provide more power supply paths to the backlight module LD, and these power supply paths can have different power supply voltages V LEDIn some embodiments, the LEDs in each dimming zone LDa are connected in series and parallel, so that the LEDs form multiple groups of LED light strings connected in parallel. The current flowing through each group of LED light strings can be the same or different, and the LED light strings emit corresponding brightness according to the current flowing through.

[0042] Referring to FIG. 6 , a backlight control method 200 according to an embodiment of the present invention includes steps 210 to 250. The backlight control method 200 can be implemented using the display device 100 and backlight control circuit 120 shown in FIG. 1 and FIG. 2 , or using an architecture with similar functionality. The following description combines the backlight control method 200 with the backlight control circuit 120 of FIG. The operating principles of some steps have already been described above and are therefore not further elaborated.

[0043] In step 210, the power supply circuit 121 continuously provides the supply voltage V during each frame. LED To the backlight module LD to light up each light-emitting diode in each dimming zone LDa.

[0044] In step 220, the local dimming circuit 122 receives the image data of the frame image to be displayed in the next frame, and calculates the local dimming signal S required for the configuration of the dimming zones LDa corresponding to the image data. LD .

[0045] In step 230 , the supply voltage adjustment circuit 124 receives the local dimming signal S LD , and according to the regional dimming signal S LD The first supply voltage adjustment signal V1 is generated based on the characteristic data of each light emitting diode in each dimming zone LDa.

[0046] In step 240, the power supply circuit 121 adjusts the supply voltage V in advance according to the first supply voltage adjustment signal V1. LED Adjust to an appropriate value. In this way, the speed at which the driving current required by each dimming zone LDa stabilizes can be accelerated, and power loss can be effectively reduced.

[0047] In step 250, the backlight driving circuit 123 generates a dimming signal S according to the local dimming signal S. LD Generates the corresponding backlight driving signal S BD To each dimming subarea LDa of the backlight module LD, so as to control the current value flowing through the light emitting diodes in each dimming subarea LDa and make them generate corresponding light emitting brightness.

[0048] In some embodiments, the backlight control method 200 further includes step 260, when the supply voltage V LEDWhen the voltage range of the corresponding image data is exceeded, the supply voltage adjustment circuit 124 adjusts the voltage according to the detection signal V of each LED in the dimming zone LDa. D Generate a second power supply voltage adjustment signal V2, and fine-tune the power supply voltage V according to the second power supply voltage adjustment signal V2. LED When the potential of the second power supply voltage adjustment signal V2 rises, the power supply circuit 121 reduces the power supply voltage V LED On the contrary, when the potential of the second supply voltage adjustment signal V2 decreases, the power supply circuit 121 increases the supply voltage V LED In this way, the supply voltage V LED Fine-tune to the desired value.

[0049] In some embodiments, the dimming zone LDa of the backlight module LD can be divided into multiple strip-shaped areas, and brightness modulation of each strip-shaped area can be achieved as needed. In some embodiments, the backlight module LD can be divided into an array of dimming zones with multiple rows and columns, and brightness modulation of each dimming zone in each row and column can be achieved as needed. It should be understood that any backlight module LD capable of multi-zone dimming is within the scope of the present invention.

[0050] The display device, backlight control circuit, and backlight control method of the present invention predict the backlight module's required supply voltage for the next frame image based on the local dimming signal and the characteristic data of each LED in each dimming zone. This advances the starting point for controlling the output voltage of the power supply circuit and adjusts the supply voltage to an appropriate value. This accelerates the stabilization of the drive current required by each dimming zone and effectively reduces power loss.

[0051] Although the present invention is disclosed above with various embodiments, they are not intended to limit the present invention. Anyone with ordinary knowledge in the technical field should be able to make some changes and modifications without departing from the spirit and scope of the present invention. Therefore, the scope of protection of the present invention should be based on the scope defined by the appended claims.

[0052] [List of Reference Numerals] 100: display device 110: display panel 120: backlight control circuit LD: backlight module LDa: dimming zone 121: power supply circuit 122: local dimming circuit 123: backlight driving circuit 124: power supply voltage adjustment circuit V LED : Supply voltage S BD : Backlight driving signal SLD : Local dimming signal V1: First power supply voltage adjustment signal V2: Second power supply voltage adjustment signal V D : Detection signal V sync : Vertical synchronization signal 200: Backlight control method 210,220,230,240,250,260: Steps.

Claims

1. A backlight control circuit, comprising: A power supply circuit, which is used to output a power supply voltage to a backlight module, wherein the backlight module has a plurality of dimming partitions, and each of the dimming partitions has a plurality of light-emitting diodes; A local dimming circuit, which is used to generate a local dimming signal according to the image data and the configuration of the plurality of dimming zones; A backlight driving circuit, used for generating a plurality of backlight driving signals to the plurality of dimming zones of the backlight module according to the regional dimming signal; as well as The supply voltage adjustment circuit is used to generate a first supply voltage adjustment signal to the power supply circuit according to the local dimming signal and the characteristic data of each light emitting diode in the plurality of dimming zones, so as to adjust the supply voltage.

2. The backlight control circuit according to claim 1, wherein the local dimming signal comprises a plurality of brightness values ​​respectively corresponding to the plurality of dimming partitions under the image data, and the plurality of brightness values ​​are provided to the backlight driving circuit to generate the corresponding plurality of backlight driving signals.

3. The backlight control circuit according to claim 1, wherein each of the backlight driving signals is a current driving signal, and the characteristic data comprises corresponding relationship data between an operating voltage and an operating current of each light emitting diode in the plurality of dimming partitions.

4. The backlight control circuit according to claim 1, wherein the power supply voltage adjustment circuit is further used to generate a second power supply voltage adjustment signal to the power supply circuit according to the detection signal of each light-emitting diode in the multiple dimming partitions to adjust the power supply voltage when the power supply voltage exceeds the voltage range corresponding to the image data.

5. The backlight control circuit according to claim 4, wherein the power supply circuit comprises: The analog regulating circuit is used for reducing the potential of the supply voltage when the potential of the second supply voltage regulating signal increases, and increasing the potential of the supply voltage when the potential of the second supply voltage regulating signal decreases. 6 . The backlight control circuit according to claim 4 , wherein the detection signal is a cathode voltage of each light emitting diode.

7. The backlight control circuit according to claim 4, wherein the detection signal is generated by the backlight driving circuit detecting a cathode voltage of each light emitting diode.

8. A display device, comprising: A display panel for displaying a frame image based on image data; A backlight module, which is used to provide a backlight source for the display panel, wherein the backlight module comprises a plurality of dimming partitions, and each of the dimming partitions has a plurality of light emitting diodes; A power supply circuit, used for outputting the power supply voltage to the backlight module; A local dimming circuit, which is used to generate a local dimming signal according to the image data and the configuration of the plurality of dimming partitions in the backlight module; A backlight driving circuit, used for generating a plurality of backlight driving signals according to the regional dimming signal; as well as The supply voltage adjustment circuit is used to generate a supply voltage adjustment signal to the power supply circuit according to the local dimming signal and the characteristic data of each light emitting diode in the plurality of dimming zones, so as to adjust the supply voltage. 9 . The display device according to claim 8 , wherein the power supply circuit is used for adjusting the supply voltage according to the supply voltage adjustment signal before the display panel displays the frame image. 10 . The display device according to claim 8 , wherein each of the backlight driving signals is a current driving signal, and the characteristic data comprises corresponding relationship data between an operating voltage and an operating current of each light emitting diode in the plurality of dimming subareas.

11. A backlight control method, comprising: Providing power supply voltage to the backlight module; Generate a local dimming signal according to the image data and the configuration of a plurality of dimming zones in the backlight module, wherein each of the dimming zones has a plurality of light emitting diodes; Generating a plurality of backlight driving signals to the plurality of dimming zones of the backlight module according to the regional dimming signal; generating a first supply voltage adjustment signal according to the local dimming signal and characteristic data of each light emitting diode in the plurality of dimming zones; as well as The supply voltage is adjusted according to the first supply voltage adjustment signal. 12 . The backlight control method according to claim 11 , wherein adjusting the supply voltage according to the first supply voltage adjustment signal is performed before a display panel provided with backlight source by the backlight module displays a frame image based on the image data. 13 . The backlight control method according to claim 11 , wherein each of the backlight driving signals is a current driving signal, and the characteristic data comprises corresponding relationship data between an operating voltage and an operating current of each light emitting diode in the plurality of dimming subareas.

14. The backlight control method according to claim 11, further comprising: When the supply voltage exceeds a voltage range corresponding to the image data, generating a second supply voltage adjustment signal according to a detection signal of each light emitting diode in the plurality of dimming subareas; and The supply voltage is adjusted according to the second supply voltage adjustment signal.

15. The backlight control method according to claim 14, wherein adjusting the supply voltage according to the second supply voltage adjustment signal comprises: The potential of the supply voltage is reduced when the potential of the second supply voltage adjustment signal increases, and the potential of the supply voltage is increased when the potential of the second supply voltage adjustment signal decreases. 16 . The backlight control method according to claim 14 , wherein the detection signal is a cathode voltage of each light emitting diode.

17. The backlight control method according to claim 14, further comprising: The cathode voltage of each light emitting diode is detected to generate the detection signal.

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