Backlight adjustment circuit, display device and backlight adjustment method

Abstract

This application belongs to the field of display, and particularly relates to a backlight adjustment circuit, a display device, and a backlight adjustment method. The backlight adjustment circuit includes a first dimming module, a second dimming module, and a selection module. The first dimming module is configured to respond to the signal of the scan signal line, conduct the PWM signal line and the driver chip. The second dimming module is configured to respond to the signal of the scan signal line, conduct the DC signal line and the driver chip. Both the first dimming module and the second dimming module are connected to the scan signal line through the selection module. The selection module is configured to respond to the control signal dynamically output according to the image by the control signal line, and proportionally distribute the scan signal line signal to the first dimming module and the second dimming module. In this application, the dimming method of the backlight module can be flexibly switched among PWM dimming, DC dimming, and PWM+DC hybrid dimming according to the dynamic range of the displayed image, reducing or eliminating the flicker of the display screen.

Description

Technical Field

[0001] This application belongs to the field of displays, and particularly relates to a backlight adjustment circuit, a display device, and a backlight adjustment method. Background Art

[0002] Currently, more and more display products use Mini LEDs as backlights. Generally speaking, Mini LEDs are used as direct-lit backlights, and the distance between their lamp beads is very small. Through a large number of dense arrangements, local dimming in a smaller range can be achieved. The backlight board of Mini LEDs can accommodate more LEDs per unit area, thus greatly increasing the number of backlights. Compared with traditional backlight designs, it can have better brightness uniformity and higher color contrast within a smaller light mixing distance, enabling the ultra-thin design of terminal products and saving electrical energy.

[0003] Traditional Mini LED backlight control technologies generally use zoning for control. For example, in a one-to-one control method, that is, each control zone corresponds to a string of LEDs, etc. That is, each control lighting zone corresponds to a control channel of a constant current driving chip. Therefore, a design for regional brightness adjustment can be carried out, so that the LEDs can be turned off in individual areas to achieve complete black, which not only reduces power consumption, but also due to the increase in the number of LEDs per unit area, realizes ultra-high contrast and fine dynamic distribution, making the bright field brighter and the dark field darker, thus making the display effect more delicate.

[0004] For Mini LED backlights, the constant current control system of the backlight lamp strip or lamp board mainly transmits and controls data with the main board through digital signals, and uses traditional single low-frequency PWM (pulse width modulation) dimming to control the brightness of the backlight module. The PWM dimming frequency is 100Hz - 500Hz, which causes problems such as display screen flickering in electronic devices, extremely affecting the user's viewing experience. Summary of the Invention

[0005] The purpose of this application is to provide a backlight adjustment circuit, a display device, and a backlight adjustment method to reduce or eliminate display screen flickering and improve the display image quality.

[0006] To achieve the above purpose, this application provides a backlight adjustment circuit, including a first dimming module. The first dimming module is connected to a scan signal line, a PWM signal line, and a driving chip. The first dimming module is used to respond to the signal of the scan signal line, conduct the PWM signal line and the driving chip. The backlight adjustment circuit further includes:

[0007] A second dimming module, the second dimming module is connected to the scan signal line, the DC signal line and the driving chip, and the second dimming module is configured to respond to the signal of the scan signal line and conduct the DC signal line and the driving chip;

[0008] A selection module, connected to the control signal line, the scan signal line, the first dimming module and the second dimming module. Both the first dimming module and the second dimming module are connected to the scan signal line through the selection module. The selection module is configured to respond to the control signal dynamically output according to the image by the control signal line and proportionally distribute the scan signal line signal to the first dimming module and the second dimming module.

[0009] Optionally, the selection module includes a first transistor and a second transistor. Among the first transistor and the second transistor: one is a P-type transistor and the other is an N-type transistor. The control ends of the first transistor and the second transistor are connected to the control signal line. The first ends of the first transistor and the second transistor are connected to the scan signal line. The second end of the first transistor is connected to the first dimming module. The second end of the second transistor is connected to the second dimming module.

[0010] Optionally, the first transistor is an N-type transistor and the second transistor is a P-type transistor. When the voltage output by the control signal line is greater than or equal to a first voltage, the first transistor operates in the saturation region and the second transistor operates in the cut-off region. When the voltage output by the control signal line is less than or equal to a second voltage, the first transistor operates in the cut-off region and the second transistor operates in the saturation region. When the voltage output by the control signal line is greater than the second voltage and less than the first voltage, both the first transistor and the second transistor operate in the variable resistance region.

[0011] Optionally, the first dimming module includes a third transistor. The third transistor is connected to the second end of the first transistor. The first end of the third transistor is connected to the PWM signal line. The second end of the third transistor is connected to the driving chip.

[0012] Optionally, the second dimming module includes a fourth transistor. The fourth transistor is connected to the second end of the second transistor. The first end of the fourth transistor is connected to the DC signal line. The second end of the fourth transistor is connected to the driving chip.

[0013] The present application further provides a display device, including:

[0014] A backlight module, including a driving board, a lamp string, a driving chip, and the backlight adjustment circuit. The backlight adjustment circuit, the lamp string, and the driving chip are all disposed on the driving board. The backlight adjustment circuit, the driving chip, and the lamp string are connected in sequence. The lamp string includes a plurality of lamp beads connected in series.

[0015] Optionally, the driving board includes at least one main partition and at least one secondary partition disposed around all of the main partitions. Each main partition and each secondary partition include the driving chip and at least one of the lamp strings. At least the main partition further includes the backlight adjustment circuit.

[0016] Optionally, the display device further includes a main board, a control module, a display panel, and the backlight module. The control module is connected to the main board, the display panel, and the backlight module;

[0017] The main board is at least used for supplying energy to the control module and detecting data signals. The control module includes a control module, a logic module, and a power module. The control module is at least used for controlling the on / off of the lamp string. The logic module is at least used for controlling the backlight adjustment circuit according to the data signals detected by the main board. The power module is at least used for converting the input voltage of the main board to supply energy to the backlight module and the display panel.

[0018] The present application further provides a backlight adjustment method. The backlight control method is applied to the display device. The display device further includes a logic module. The backlight control method includes:

[0019] Detecting data signals and parsing the data signals into a display image. The display image is one of a relatively low dynamic range image, a medium dynamic range image, and a high dynamic range image. Judging the type of the display image according to the dynamic range of the display image;

[0020] When it is confirmed that the display image is a low dynamic range image, controlling the voltage output by the logic module to the control signal line to be greater than or equal to a first voltage, so that the first dimming module turns on the PWM signal line and the driving chip;

[0021] When it is confirmed that the display image is a medium dynamic range image, controlling the voltage output by the logic module to the control signal line to be greater than a second voltage and less than the first voltage, so that the first dimming module turns on the PWM signal line and the driving chip, and enabling the second dimming module to turn on the DC signal line and the driving chip;

[0022] When it is confirmed that the display image is a high dynamic range image, controlling the voltage output by the logic module to the control signal line to be less than or equal to the second voltage, so that the second dimming module turns on the DC signal line and the driving chip.

[0023] Optionally, when it is confirmed that the displayed image is a medium dynamic image, before controlling the logic module to output voltage to the control signal line, obtain the brightness of the displayed image, and adjust the voltage output by the logic module to the control signal line according to the brightness of the displayed image, so as to adjust the ratio of the signals output by the PWM signal line and the DC signal line to the driving chip.

[0024] The backlight adjustment circuit, display device, and backlight adjustment method disclosed in this application have the following beneficial effects:

[0025] In this application, the backlight adjustment circuit includes a first dimming module, a second dimming module, and a selection module. The first dimming module is used to respond to the signal of the scanning signal line and conduct the PWM signal line and the driving chip. The second dimming module is used to respond to the signal of the scanning signal line and conduct the DC signal line and the driving chip. The selection module is used to respond to the control signal dynamically output by the control signal line according to the image, and proportionally distribute the scanning signal line signal to the first dimming module and the second dimming module, so that the dimming method of the backlight module can be flexibly switched between PWM dimming, DC dimming, and PWM+DC hybrid dimming according to the dynamic range of the displayed image, thereby reducing or eliminating the flicker of the displayed picture and improving the display quality of the display panel.

[0026] Other features and advantages of this application will become apparent through the following detailed description, or will be partially learned through the practice of this application.

[0027] It should be understood that the above general description and the following detailed description are only exemplary and explanatory, and cannot limit this disclosure. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] The accompanying drawings herein are incorporated into the specification and constitute a part of this specification, showing embodiments consistent with this application, and are used together with the specification to explain the principles of this application. Obviously, the accompanying drawings in the following description are only some embodiments of this application. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0029] Figure 1 It is a schematic structural diagram of the backlight adjustment circuit in Embodiment 1 of this application.

[0030] Figure 2 It is a schematic diagram of the input and output signals of the backlight adjustment circuit in Embodiment 1 of this application.

[0031] Figure 3 It is a schematic structural diagram of the backlight module in Embodiment 1 of this application.

[0032] Figure 4It is a schematic structural diagram of the display device in the second embodiment of the present application.

[0033] Figure 5 It is a schematic structural diagram of the backlight module in the second embodiment of the present application.

[0034] Figure 6 It is a flowchart of the backlight adjustment method in the third embodiment of the present application.

[0035] Figure 7 It is a flowchart of the backlight adjustment method in the third embodiment of the present application.

[0036] Figure 8 It is a schematic diagram of the PWM dimming signal at different brightness levels.

[0037] Figure 9 It is a schematic diagram of the input and output signals of the backlight adjustment circuit at low brightness.

[0038] Figure 10 It is a schematic diagram of the input and output signals of the backlight adjustment circuit at medium brightness.

[0039] Figure 11 It is a schematic diagram of the input and output signals of the backlight adjustment circuit at high brightness.

[0040] Description of the reference numerals:

[0041] 100, backlight module; 110, first dimming module; 111, third transistor; 120, second dimming module; 121, fourth transistor; 130, selection module 130; 131, first transistor; 132, second transistor; 140, driving chip; 151, PWM signal line; 152, DC signal line; 153, scanning signal line; 154, control signal line; 155, output signal line; 160, lamp string; 170, driving board; 171, main partition; 172, sub - partition;

[0042] 200, control module; 210, control module; 220, logic module; 230, power module;

[0043] 300, main board; 400, display panel. Detailed implementation manners

[0044] Now, the exemplary embodiments will be described more fully with reference to the accompanying drawings. However, the exemplary embodiments can be implemented in various forms and should not be construed as limited to the examples set forth herein; rather, these embodiments are provided so that this application will be more complete and comprehensive, and will fully convey the concept of the exemplary embodiments to those skilled in the art.

[0045] In addition, the described features, structures, or characteristics may be combined in one or more embodiments in any suitable manner. In the following description, numerous specific details are provided to give a thorough understanding of the embodiments of the present application. However, those skilled in the art will realize that the technical solutions of the present application may be practiced without one or more of the specific details, or other methods, components, devices, steps, etc. may be adopted. In other cases, well-known methods, devices, implementations, or operations are not shown or described in detail to avoid obscuring aspects of the present application.

[0046] The present application will be further described in detail below in conjunction with the accompanying drawings and specific embodiments. It should be noted here that the technical features involved in the various embodiments of the present application described below can be combined with each other as long as they do not conflict with each other. The embodiments described below by referring to the accompanying drawings are exemplary and are intended to explain the present application and should not be construed as limiting the present application.

[0047] Embodiment 1

[0048] See Figure 1 As shown, in this embodiment, the backlight adjustment circuit includes a first dimming module 110, a second dimming module 120, and a selection module 130.

[0049] The first dimming module 110 is connected to the scan signal line 153, the PWM signal line 151, and the driver chip 140, and the first dimming module 110 and the driver chip 140 are connected through the output signal line 155. The scan signal line 153 outputs the scan signal Sn, and the first dimming module 110 is used to respond to the signal of the scan signal line 153 and conduct the PWM signal line 151 and the driver chip 140.

[0050] The second dimming module 120 is connected to the scan signal line 153, the DC signal line 152, and the driver chip 140, and the second dimming module 120 and the driver chip 140 are also connected through the output signal line 155. The second dimming module 120 is used to respond to the signal of the scan signal line 153 and conduct the DC signal line 152 and the driver chip 140.

[0051] The selection module 130 is connected to the control signal line 154, the scan signal line 153, the first dimming module 110, and the second dimming module 120. Both the first dimming module 110 and the second dimming module 120 are connected to the scan signal line 153 through the selection module 130. The selection module 130 is used to respond to the control signal dynamically output according to the image on the control signal line 154 and proportionally distribute the signal of the scan signal line 153 to the first dimming module 110 and the second dimming module 120.

[0052] See Figure 2As shown, the signal ratio of the scan signal line 153 is distributed to the first dimming module 110 and the second dimming module 120. That is to say, when all the signals of the scan signal line 153 are distributed to the first dimming module 110, the PWM signal line 151 and the output signal line 155 are turned on, and the output signal line 155 only outputs the PWM dimming signal to the driving chip 140; when all the signals of the scan signal line 153 are distributed to the second dimming module 120, the DC signal line 152 and the output signal line 155 are turned on, and the output signal line 155 only outputs the DC dimming signal to the driving chip 140; when the signals of the scan signal line 153 are partially distributed to the first dimming module 110 and partially distributed to the second dimming module 120, both the PWM signal line 151 and the DC signal line 152 are turned on with the output signal line 155, and the output signal line 155 outputs both the PWM dimming signal and the DC dimming signal to the driving chip 140 at the same time.

[0053] See Figure 3 As shown, the backlight module 100 includes a driving board 170, a lamp string 160 and a driving chip 140. The lamp string 160 and the driving chip 140 are both arranged on the driving board 170. Each driving chip 140 has a plurality of control channels, and each control channel is used to control the current magnitude of each lamp string 160. Each lamp string 160 is composed of a plurality of lamp beads connected in series, and the lamp beads may include LED lamps, Mini LED lamps and Micro LED lamps.

[0054] In this embodiment, the backlight adjustment circuit includes a first dimming module 110, a second dimming module 120 and a selection module 130. The first dimming module 110 is used to respond to the signal of the scan signal line 153 and turn on the PWM signal line 151 and the driving chip 140. The second dimming module 120 is used to respond to the signal of the scan signal line 153 and turn on the DC signal line 152 and the driving chip 140. The selection module 130 is used to respond to the control signal dynamically output according to the image on the control signal line 154, and proportionally distribute the signal of the scan signal line 153 to the first dimming module 110 and the second dimming module 120, so that the dimming mode of the backlight module 100 can be flexibly switched between PWM dimming, DC dimming and PWM+DC hybrid dimming according to the dynamic range of the displayed image, thereby reducing or eliminating the flicker of the displayed picture and improving the display quality of the display panel 400.

[0055] Exemplarily, see Figure 1As shown, the selection module 130 includes a first transistor 131 and a second transistor 132. Among the first transistor 131 and the second transistor 132, one is a P-type transistor and the other is an N-type transistor. The control terminals of the first transistor 131 and the second transistor 132 are connected to the control signal line 154. The first terminals of the first transistor 131 and the second transistor 132 are connected to the scan signal line 153. The second terminal of the first transistor 131 is connected to the first dimming module 110. The second terminal of the second transistor 132 is connected to the second dimming module 120.

[0056] When the transistor is turned on, it operates in the saturation region. When the transistor is turned off, it operates in the cut-off region. Among the first transistor 131 and the second transistor 132, one is a P-type transistor and the other is an N-type transistor. When the first transistor 131 is turned on, the second transistor 132 is turned off. When the first transistor 131 is turned off, the second transistor 132 is turned on.

[0057] The control terminal of the first transistor 131 is the gate, the first terminal of the first transistor 131 is the source, and the second terminal of the first transistor 131 is the drain. The control terminal of the second transistor 132 is the gate, the first terminal of the second transistor 132 is the source, and the second terminal of the second transistor 132 is the drain.

[0058] The selection module 130 includes a first transistor 131 and a second transistor 132. Among the first transistor 131 and the second transistor 132, one is a P-type transistor and the other is an N-type transistor. With such a design, when the first transistor 131 is turned on and the second transistor 132 is turned off, the output signal line 155 only outputs the PWM dimming signal to the driving chip 140. Or when the first transistor 131 is turned off and the second transistor 132 is turned on, the output signal line 155 only outputs the DC dimming signal to the driving chip 140.

[0059] See Figure 1 As shown, the first transistor 131 is an N-type transistor and the second transistor 132 is a P-type transistor. When the voltage output by the control signal line 154 is greater than or equal to the first voltage, the first transistor 131 operates in the saturation region and the second transistor 132 operates in the cut-off region. When the voltage output by the control signal line 154 is less than or equal to the second voltage, the first transistor 131 operates in the cut-off region and the second transistor 132 operates in the saturation region. When the voltage output by the control signal line 154 is greater than the second voltage and less than the first voltage, both the first transistor 131 and the second transistor 132 operate in the variable resistance region.

[0060] That is to say, when the output voltage of the control signal line 154 is greater than the second voltage and less than the first voltage, neither the first transistor 131 nor the second transistor 132 is fully turned on. The first dimming module 110 controls the magnitude of the PWM dimming voltage, and the second dimming module 120 controls the magnitude of the DC dimming voltage. The output signal line 155 outputs both the PWM dimming signal and the DC dimming signal to the driving chip 140 simultaneously.

[0061] When the output voltage of the control signal line 154 is greater than or equal to the first voltage, the output signal line 155 only outputs the PWM dimming signal to the driving chip 140. For low-dynamic-range images, using PWM dimming can reduce power consumption. When the output voltage of the control signal line 154 is less than or equal to the second voltage, the output signal line 155 only outputs the DC dimming signal to the driving chip 140. For high-dynamic-range images, using DC dimming can eliminate display flicker. When the output voltage of the control signal line 154 is greater than the second voltage and less than the first voltage, the output signal line 155 outputs both the PWM dimming signal and the DC dimming signal to the driving chip 140 simultaneously. For medium-dynamic-range images, it can reduce power consumption to a certain extent while reducing or eliminating display flicker.

[0062] See Figure 1 As shown, the first dimming module 110 includes a third transistor 111. The third transistor 111 is connected to the second end of the first transistor 131. The first end of the third transistor 111 is connected to the PWM signal line 151, and the second end of the third transistor 111 is connected to the driving chip 140. The control end of the third transistor 111 is the gate, the first end of the third transistor 111 is the source, and the second end of the third transistor 111 is the drain.

[0063] The first dimming module 110 includes a third transistor 111. When the output voltage of the control signal line 154 is greater than or equal to the first voltage, the third transistor 111 is fully turned on, and the output signal line 155 only outputs the PWM dimming signal to the driving chip 140. When the output voltage of the control signal line 154 is greater than the second voltage and less than the first voltage, the third transistor 111 is not fully turned on, that is, the third transistor 111 operates in the variable resistance region, and the third transistor 111 controls the magnitude of the PWM dimming signal voltage.

[0064] See Figure 1 As shown, the second dimming module 120 includes a fourth transistor 121. The fourth transistor 121 is connected to the second end of the second transistor 132. The first end of the fourth transistor 121 is connected to the DC signal line 152, and the second end of the fourth transistor 121 is connected to the driving chip 140. The control end of the fourth transistor 121 is the gate, the first end of the fourth transistor 121 is the source, and the second end of the fourth transistor 121 is the drain.

[0065] The second dimming module 120 includes a fourth transistor 121. When the output voltage of the control signal line 154 is less than or equal to the second voltage, the fourth transistor 121 is fully turned on, and the output signal line 155 only outputs a DC dimming signal to the driving chip 140. When the output voltage of the control signal line 154 is greater than the second voltage and less than the first voltage, the fourth transistor 121 is not fully turned on, that is, the fourth transistor 121 operates in the variable resistance region, and the fourth transistor 121 controls the magnitude of the DC dimming signal voltage.

[0066] Embodiment 2

[0067] Refer to Figures 3 to 5 As shown, the display device includes a backlight module 100 and a control module 200 connected to each other. The backlight module 100 includes a driving board 170, a lamp string 160, a driving chip 140, and a backlight adjustment circuit. The backlight adjustment circuit includes the backlight adjustment circuit disclosed in Embodiment 1. The backlight adjustment circuit, the lamp string 160, and the driving chip 140 are all disposed on the driving board 170. The backlight adjustment circuit, the driving chip 140, and the lamp string 160 are connected in sequence, and the lamp string 160 includes a plurality of lamp beads connected in series.

[0068] The control module 200 includes a logic module 220. The logic module 220 controls the control signals of the backlight adjustment circuit, including the PWM dimming signal of the PWM signal line 151, the DC dimming signal of the DC signal line 152, the scan signal Sn of the scan signal line 153, and the control signal LC of the control signal line 154.

[0069] It should be noted that the backlight adjustment circuit can be disposed on the driving board 170, but it is not limited thereto. The backlight adjustment circuit can also be disposed on the logic module 220, which can be determined according to the specific situation.

[0070] The display device includes a backlight module 100. In the backlight module 100, the backlight adjustment circuit, the driving chip 140, and the lamp string 160 are connected in sequence. The control signal line 154 outputs a control signal according to the image dynamically, and controls the backlight adjustment circuit to output a PWM dimming signal, a DC dimming signal, or a PWM+DC dimming signal to the driving chip 140 to drive the lamp string 160, so that the dimming method of the backlight module 100 can be flexibly switched among PWM dimming, DC dimming, and PWM+DC hybrid dimming according to the dynamic range of the display image, thereby reducing or eliminating the flicker of the display screen and improving the display image quality of the display panel 400.

[0071] Refer to Figures 3 to 5 As shown, the driving board 170 includes at least one main partition 171 and at least one sub-partition 172 disposed around all the main partitions 171. Each main partition 171 and each sub-partition 172 include a driving chip 140 and at least one lamp string 160. At least the main partition 171 further includes a backlight adjustment circuit.

[0072] For a display device, especially a large-size Mini LED backlight display device, its backlight module 100 can perform zoned dimming. For the secondary zone 172, but not limited to this, the secondary zone 172 can also use a backlight adjustment circuit for dimming, which can be determined according to the specific situation. For the primary zone 171, a backlight adjustment circuit can be used for dimming, that is, according to the dynamic range of the displayed image, it can flexibly switch among PWM dimming, DC dimming, and PWM+DC hybrid dimming.

[0073] The effective viewing area of a large-size display device is mainly concentrated in the middle area of the screen. That is, when the user is viewing, the attention of the user's eyes is mainly concentrated in the middle area of the screen. For the edge area of the screen, the user's eye attention is scattered. For the secondary zone 172, PWM dimming can be used to reduce power consumption. For the primary zone 171, a backlight adjustment circuit can be used for dimming, that is, according to the dynamic range of the displayed image, it can flexibly switch among PWM dimming, DC dimming, and PWM+DC hybrid dimming to reduce or eliminate the flicker of the displayed image and improve the display quality of the display device.

[0074] See Figures 3 to 5 As shown, the display device further includes a main board 300 and a display panel 400. The control module 200 is connected to the main board 300, the display panel 400, and the backlight module 100. The main board 300 is at least used to supply energy to the control module 200 and detect data signals. The control module 200 includes a control module 210, a logic module 220, and a power module 230. The control module 210 is at least used to control the on / off of the lamp string 160. The logic module 220 is at least used to control the backlight adjustment circuit according to the data signals detected by the main board 300. The power module 230 is at least used to convert the input voltage of the main board 300 to supply energy to the backlight module 100 and the display panel 400.

[0075] The main board 300 detects data signals and parses the data signals into a displayed image. The logic module 220 outputs signals to the control signal line 154 according to the dynamic range of the displayed image, and controls the dimming method of the primary zone 171 to flexibly switch among PWM dimming, DC dimming, and PWM+DC hybrid dimming, so as to reduce or eliminate the flicker of the displayed image, improve the display quality of the display device, and reduce energy consumption to a certain extent.

[0076] Embodiment III

[0077] In this embodiment, the backlight control method is applied to the display device in Embodiment II. See Figure 6 and Figure 7 As shown, the backlight control method includes:

[0078] S100: Detect data signals and parse the data signals into a displayed image. The displayed image is one of a relatively low-dynamic image, a medium-dynamic image, and a high-dynamic image, and determine the type of the displayed image according to the dynamic range of the displayed image.

[0079] S200: When it is confirmed that the displayed image is a low-dynamic-range image, the control logic module 220 outputs a voltage greater than or equal to the first voltage to the control signal line 154, causing the first dimming module 110 to turn on the PWM signal line 151 and the driving chip 140.

[0080] S300: When it is confirmed that the displayed image is a medium-dynamic-range image, the control logic module 220 outputs a voltage greater than the second voltage and less than the first voltage to the control signal line 154, causing the first dimming module 110 to turn on the PWM signal line 151 and the driving chip 140, and causing the second dimming module 120 to turn on the DC signal line 152 and the driving chip 140.

[0081] S400: When it is confirmed that the displayed image is a high-dynamic-range image, the control logic module 220 outputs a voltage less than or equal to the second voltage to the control signal line 154, causing the second dimming module 120 to turn on the DC signal line 152 and the driving chip 140.

[0082] The displayed image can be divided into a low-dynamic-range image, a medium-dynamic-range image, and a high-dynamic-range image according to the dynamic range. The main board 300 detects the data signal, parses the data signal into a displayed image, and determines the type of the displayed image according to the dynamic range of the displayed image. When it is confirmed that the displayed image is a low-dynamic-range image, PWM dimming is adopted. When it is confirmed that the displayed image is a medium-dynamic-range image, PWM+DC dimming is adopted. When it is confirmed that the displayed image is a high-dynamic-range image, DC dimming is adopted. The backlight module 100 may include a plurality of main partitions 171, and the dimming method of each main partition 171 may be different.

[0083] According to the dynamic range of the displayed image, flexible switching between PWM dimming, DC dimming, and PWM+DC hybrid dimming can reduce or eliminate the flicker of the displayed screen, improve the display image quality of the display device, and at the same time reduce the energy consumption to a certain extent.

[0084] See Figures 8 to 11 As shown, in step S300, when it is confirmed that the displayed image is a medium-dynamic-range image, before the control logic module 220 outputs a voltage to the control signal line 154, the brightness of the displayed image can be obtained, and the voltage output by the control logic module 220 to the control signal line 154 can be adjusted according to the brightness of the displayed image, so as to adjust the ratio of the signals output by the PWM signal line 151 and the DC signal line 152 to the driving chip 140.

[0085] That is to say, when the displayed image is a low-brightness image, by adjusting the voltage of the control signal line 154, the ratio of the signal of the PWM signal line 151 is increased. When the displayed image is a high-brightness image, by adjusting the voltage of the control signal line 154, the ratio of the signal of the DC signal line 152 is increased.

[0086] Before the control logic module 220 outputs voltage to the control signal line 154, the brightness of the display image can be obtained, the voltage of the control signal line 154 can be adjusted according to the brightness of the display image, and the ratio of the PWM signal line 151 signal and the DC signal line 152 signal output to the driving chip 140 can be adjusted, which can reduce or eliminate the flicker of the display screen and improve the display image quality of the display device while reducing the energy consumption to a certain extent.

[0087] The terms "first", "second", etc. are used for descriptive purposes only and cannot be construed as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, features defined with "first", "second", etc. may explicitly or implicitly include one or more of such features. In the description of this application, "a plurality" means two or more unless otherwise specifically defined.

[0088] In this application, unless otherwise clearly specified and limited, terms such as "assembly", "connection", etc. should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or integrated; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, and it can be the communication inside two components or the interaction relationship between two components. For those of ordinary skill in the art, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0089] In the description of this specification, the descriptions referring to terms such as "some embodiments", "exemplarily", etc. mean that the specific features, structures, materials or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of this application. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in a suitable manner in any one or more embodiments or examples. In addition, without contradiction, those skilled in the art can combine and combine the different embodiments or examples described in this specification and the features of different embodiments or examples.

[0090] Although the embodiments of this application have been shown and described above, it can be understood that the above embodiments are exemplary and should not be construed as limiting this application. Those of ordinary skill in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of this application. Therefore, any changes or modifications made in accordance with the claims and the description of this application shall fall within the scope covered by the patent of this application.

Claims

1. A backlight adjustment circuit, comprising a first dimming module, wherein the first dimming module is connected to a scan signal line, a PWM signal line and a driving chip, and the first dimming module is configured to respond to a signal on the scan signal line and conduct the PWM signal line and the driving chip. Characterized in that: The backlight adjustment circuit further includes: A second dimming module, the second dimming module is connected to the scan signal line, a DC signal line and the driving chip, and the second dimming module is configured to respond to a signal on the scan signal line and conduct the DC signal line and the driving chip; A selection module, connected to a control signal line, the scan signal line, the first dimming module and the second dimming module, both the first dimming module and the second dimming module are connected to the scan signal line through the selection module, and the selection module is configured to respond to a control signal dynamically output by the control signal line according to an image and proportionally distribute the scan signal line signal to the first dimming module and the second dimming module.

2. The backlight adjustment circuit according to claim 1, Characterized in that: The selection module includes a first transistor and a second transistor. Among the first transistor and the second transistor: one is a P-type transistor and the other is an N-type transistor. The control ends of the first transistor and the second transistor are connected to the control signal line, the first ends of the first transistor and the second transistor are connected to the scan signal line, the second end of the first transistor is connected to the first dimming module, and the second end of the second transistor is connected to the second dimming module.

3. The backlight adjustment circuit according to claim 2, Characterized in that: The first transistor is an N-type transistor and the second transistor is a P-type transistor. When the voltage output by the control signal line is greater than or equal to a first voltage, the first transistor operates in the saturation region and the second transistor operates in the cut-off region. When the voltage output by the control signal line is less than or equal to a second voltage, the first transistor operates in the cut-off region and the second transistor operates in the saturation region. When the voltage output by the control signal line is greater than the second voltage and less than the first voltage, both the first transistor and the second transistor operate in the variable resistance region.

4. The backlight adjustment circuit according to claim 2, Characterized in that: The first dimming module includes a third transistor, the third transistor is connected to the second end of the first transistor, the first end of the third transistor is connected to the PWM signal line, and the second end of the third transistor is connected to the driving chip.

5. The backlight adjustment circuit according to claim 2, Characterized in that: The second dimming module includes a fourth transistor, the fourth transistor is connected to the second end of the second transistor, the first end of the fourth transistor is connected to the DC signal line, and the second end of the fourth transistor is connected to the driving chip.

6. A display device, Characterized in that: Comprising: A backlight module, comprising a driving board, a lamp string, a driving chip, and a backlight adjustment circuit according to any one of claims 1 to 5. The backlight adjustment circuit, the lamp string, and the driving chip are all disposed on the driving board. The backlight adjustment circuit, the driving chip, and the lamp string are connected in sequence. The lamp string includes a plurality of lamp beads connected in series.

7. The display device according to claim 6, wherein, the driving board includes at least one main partition and at least one secondary partition disposed around all of the main partitions. Each main partition and each secondary partition include the driving chip and at least one of the lamp strings. At least the main partition further includes the backlight adjustment circuit.

8. The display device according to claim 6, wherein, the display device further includes a main board, a control module, a display panel, and the backlight module. The control module is connected to the main board, the display panel, and the backlight module; the main board is at least used for supplying energy to the control module and detecting data signals. The control module includes a control module, a logic module, and a power module. The control module is at least used for controlling the on / off of the lamp string. The logic module is at least used for controlling the backlight adjustment circuit according to the data signals detected by the main board. The power module is at least used for converting the input voltage of the main board to supply energy to the backlight module and the display panel.

9. A backlight adjustment method, wherein, the backlight control method is applied to the display device according to claim 6. The display device further includes a logic module. The backlight control method includes: detecting data signals and parsing the data signals into a display image, where the display image is one of a relatively low dynamic range image, a medium dynamic range image, and a high dynamic range image, and determining the type of the display image according to the dynamic range of the display image; when it is confirmed that the display image is a low dynamic range image, controlling the logic module to output a voltage greater than or equal to a first voltage to the control signal line, so that the first dimming module turns on the PWM signal line and the driving chip; when it is confirmed that the display image is a medium dynamic range image, controlling the logic module to output a voltage greater than a second voltage and less than the first voltage to the control signal line, so that the first dimming module turns on the PWM signal line and the driving chip, and so that the second dimming module turns on the DC signal line and the driving chip; when it is confirmed that the display image is a high dynamic range image, controlling the logic module to output a voltage less than or equal to the second voltage to the control signal line, so that the second dimming module turns on the DC signal line and the driving chip.

10. The backlight adjustment method according to claim 9, wherein, when it is confirmed that the display image is a medium dynamic range image, before controlling the logic module to output a voltage to the control signal line, obtaining the brightness of the display image, and adjusting the voltage output by the logic module to the control signal line according to the brightness of the display image, so as to adjust the ratio of the signals output by the PWM signal line and the DC signal line to the driving chip.

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