CN117275419A - Driving method of display device and display device - Google Patents
Driving method of display device and display device Download PDFInfo
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- CN117275419A CN117275419A CN202210669073.4A CN202210669073A CN117275419A CN 117275419 A CN117275419 A CN 117275419A CN 202210669073 A CN202210669073 A CN 202210669073A CN 117275419 A CN117275419 A CN 117275419A
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- G—PHYSICS
- G09—EDUCATION; CRYPTOGRAPHY; DISPLAY; ADVERTISING; SEALS
- G09G—ARRANGEMENTS OR CIRCUITS FOR CONTROL OF INDICATING DEVICES USING STATIC MEANS TO PRESENT VARIABLE INFORMATION
- G09G3/00—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes
- G09G3/20—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters
- G09G3/34—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters by control of light from an independent source
- G09G3/3406—Control of illumination source
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- G—PHYSICS
- G09—EDUCATION; CRYPTOGRAPHY; DISPLAY; ADVERTISING; SEALS
- G09G—ARRANGEMENTS OR CIRCUITS FOR CONTROL OF INDICATING DEVICES USING STATIC MEANS TO PRESENT VARIABLE INFORMATION
- G09G3/00—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes
- G09G3/20—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters
- G09G3/34—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters by control of light from an independent source
- G09G3/3406—Control of illumination source
- G09G3/3413—Details of control of colour illumination sources
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- G—PHYSICS
- G09—EDUCATION; CRYPTOGRAPHY; DISPLAY; ADVERTISING; SEALS
- G09G—ARRANGEMENTS OR CIRCUITS FOR CONTROL OF INDICATING DEVICES USING STATIC MEANS TO PRESENT VARIABLE INFORMATION
- G09G2320/00—Control of display operating conditions
- G09G2320/02—Improving the quality of display appearance
- G09G2320/0233—Improving the luminance or brightness uniformity across the screen
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Abstract
The invention discloses a driving method of a display device and the display device, wherein in the image display process, when brightness change is generated in a local area of a display image, the first brightness of the current display image is determined; determining a first driving current corresponding to the first brightness according to the first brightness and a relation between the predetermined brightness and the driving current; the duty ratio of the first driving current of each partition in the backlight module corresponding to other areas except the local area of the display image is adjusted; and driving the light sources of each partition to emit light by adopting the adjusted first driving current and the duty ratio so as to keep the brightness of the display image in other areas unchanged. When brightness change is generated in a local area of a display image by adopting an analog and digital mixed dimming technology, the duty ratio of driving current of corresponding subareas of other areas except the local area is compensated, so that the brightness of the other areas is kept unchanged, the contrast ratio of the display image is improved, and the image display effect is optimized.
Description
Technical Field
The present invention relates to the field of display technologies, and in particular, to a driving method of a display device and a display device.
Background
As a mainstream display screen at present, the liquid crystal display screen has the advantages of low power consumption, small volume, low radiation and the like. The liquid crystal display panel is a non-self-luminous panel and needs to be matched with a backlight module for use.
The current direct type backlight module generally adopts a light emitting diode (Light Emitting Diode, abbreviated as an LED) as a backlight source, and has the advantages of high backlight brightness, no reduction in brightness after long-time use, and the like. The light source in the backlight module is divided into a plurality of subareas, and the higher contrast ratio and lower dark field brightness can be achieved by matching with the regional dimming technology.
At present, when dimming the backlight, the driving current of the whole backlight needs to be changed, so that when the brightness of a local area in a picture changes, the brightness of the whole picture also changes due to the change of the driving current of the whole backlight, and the display effect is affected.
Disclosure of Invention
In some embodiments of the present invention, a driving method of a display device includes: determining a first brightness of a currently displayed image when the displayed image generates brightness variation in a local area in the image display process; determining a first driving current corresponding to the first brightness according to the first brightness and a relation between the predetermined brightness and the driving current; the duty ratio of the first driving current of each partition in the backlight module corresponding to other areas except the local area of the display image is adjusted; and driving the light sources of each partition to emit light by adopting the adjusted first driving current and the duty ratio so as to keep the brightness of the display image in other areas unchanged. The first brightness is the average brightness of the display image after brightness change is generated in the local area.
When brightness change is generated in a local area of a display image by adopting an analog and digital mixed dimming technology, the duty ratio of driving current of corresponding subareas of other areas except the local area is compensated, so that the brightness of the other areas is kept unchanged, the contrast ratio of the display image is improved, and the image display effect is optimized.
In some embodiments of the present invention, when the driving method of the display device is applied to a scene where the driving current is reduced from large to small, the effects of improving the light emitting efficiency and reducing the power consumption can be achieved.
In some embodiments of the present invention, after obtaining the average brightness of the display image, the driving current of the backlight module is determined according to the relationship curve between the driving current and the relative brightness.
In some embodiments of the present invention, the duty cycle of the first drive current is determined based on the second luminance, the duty cycle of the second drive current, and the first luminance. The second brightness is the average brightness before the brightness change of the display image in the local area, and the second driving current is the driving current corresponding to the second brightness.
The light emission luminance is directly related to the current value of the driving current, and also to the duty ratio of the driving current. When the brightness of the display image changes, the driving current value is determined according to the corresponding relation between the brightness and the driving current, so that the brightness is adjusted by the duty ratio of the driving current in other areas.
In some embodiments of the present invention, the duty cycle of the first drive current is determined using the following formula:
D 1 ＝D 2 (L 2 /L 1 )；
wherein D is 1 Represents the duty cycle of the first driving current, D 2 Representing the duty cycle of the second drive current, L 1 Represents a first brightness, L 2 Representing a second brightness.
The current display image is an image of the previous frame display image after the luminance change is locally generated, and then the average luminance (L 2 ) And a drive current duty ratio (D 2 ) As a known parameter, the average luminance (L 1 ) In the case of determining the driving current, the correspondence between the driving current and the relative brightness can be obtained, and thus, in L1, L 2 And D 2 In the known case, the duty ratio (D 1 )。
In some embodiments of the present invention, for a local area where brightness changes occur, a ratio of brightness of a portion of an image corresponding to a certain partition in a display image to maximum brightness may be used as a duty ratio of a first driving current of the partition.
In some embodiments of the present invention, the brightness of each partition in the backlight module is determined according to the brightness distribution of the display image, so that when the display image is divided according to the partition corresponding to the backlight module, the average value of the brightness of the display image in each partition is the average brightness of the display image.
In some embodiments of the present invention, a display device includes: a display panel and a backlight module; the backlight module comprises a plurality of light sources and a driving chip. The plurality of light sources are divided into a plurality of partitions, each partition comprises at least one light source, and the light sources in the same partition are connected in series; the driving chip is electrically connected with each partition and is used for providing driving signals for each partition; the driving chip is used for determining the first brightness of the current display image when the display image generates brightness change in the local area in the image display process; the first brightness is the average brightness of the display image after brightness change is generated in the local area; determining a first driving current corresponding to the first brightness according to the first brightness and a relation between the predetermined brightness and the driving current; the duty ratio of the first driving current of each partition in the backlight module corresponding to the other areas except the local area of the displayed image is adjusted; and driving the light sources of each partition to emit light by adopting the adjusted first driving current and the duty ratio so as to keep the brightness of the display image in other areas unchanged.
In some embodiments of the present invention, the driving chip is specifically configured to determine a second brightness of the display image and a duty ratio of the second driving current; determining the duty ratio of the first driving current according to the second brightness, the duty ratio of the second driving current and the first brightness;
The second brightness is the average brightness before the brightness change of the display image in the local area, and the second driving current is the driving current corresponding to the second brightness;
the driving chip determines the duty cycle of the first driving current using the following formula:
D 1 ＝D 2 (L 2 /L 1 )；
wherein D is 1 Represents the duty cycle of the first driving current, D 2 Representing the duty cycle of the second drive current, L 1 Represents a first brightness, L 2 Representing a second brightness.
In some embodiments of the present invention, the driver chip is a Micro LED driver chip.
Drawings
In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings that are needed in the embodiments of the present invention will be briefly described below, and it is obvious that the drawings described below are only some embodiments of the present invention, and other drawings may be obtained according to these drawings without inventive effort for a person skilled in the art.
Fig. 1 is a schematic cross-sectional structure of a display device according to an embodiment of the present invention;
FIG. 2 is a flowchart of a driving method of a display device according to an embodiment of the present invention;
FIG. 3 is a graph showing the relationship between the driving current and the relative brightness according to the embodiment of the present invention;
FIG. 4 is a graph showing the relationship between the driving current and the driving voltage according to the embodiment of the present invention;
FIG. 5 is a second flowchart of a driving method of a display device according to an embodiment of the invention;
FIG. 6 is a schematic diagram of a display image according to an embodiment of the present invention;
FIG. 7 is a second schematic diagram of a display image according to an embodiment of the present invention;
FIG. 8 is a third schematic diagram of a display image according to an embodiment of the present invention;
FIG. 9 is a diagram of a display image according to an embodiment of the present invention;
fig. 10 is a schematic perspective view of a display device according to an embodiment of the present invention;
fig. 11 is a schematic top view of a lamp panel according to an embodiment of the present invention;
fig. 12 is a schematic cross-sectional structure of a lamp panel according to an embodiment of the present invention.
Detailed Description
In order that the above objects, features and advantages of the invention will be readily understood, a further description of the invention will be rendered by reference to specific embodiments thereof which are illustrated in the appended drawings. However, the exemplary embodiments can be embodied in many forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the concept of the example embodiments to those skilled in the art. The same reference numerals in the drawings denote the same or similar structures, and thus a repetitive description thereof will be omitted. The words expressing the positions and directions described in the present invention are described by taking the drawings as an example, but can be changed according to the needs, and all the changes are included in the protection scope of the present invention. The drawings of the present invention are merely schematic representations of relative positional relationships and are not intended to represent true proportions.
Fig. 1 is a schematic cross-sectional structure of a display device according to an embodiment of the present invention.
As shown in fig. 1, the display device includes: a backlight module 100 and a display panel 200.
The display panel 200 is located at the light emitting side of the backlight module 100 for displaying images. The shape and size of the display panel 200 and the shape and size of the display device are adapted. When applied to the fields of televisions, mobile terminals, etc., the display panel 200 may be configured as a rectangle including a top side, a bottom side, a left side and a right side, wherein the top side is opposite to the bottom side, the left side is opposite to the right side, the top side is connected to one end of the left side and one side of the right side, and the bottom side is connected to the other end of the left side and the other end of the right side, respectively. When applied to the special-shaped display device, the display panel 200 may also take a circular shape or the like, which is not limited herein.
The display panel 200 is a transmissive display panel, and is capable of modulating the transmittance of light, but does not emit light itself. The display panel 200 has a plurality of pixel units arranged in an array, and each pixel unit can independently control the transmittance and color of the light incident on the pixel unit by the backlight module 100, so that the light transmitted by all the pixel units forms a displayed image. In a specific implementation, the display panel 200 may be a liquid crystal display panel, in which liquid crystal is disposed between two pieces of conductive glass, and the liquid crystal is driven by an electric field between two electrodes to cause an electric field effect of twisting liquid crystal molecules, so as to realize a function of controlling transmission or shielding of light emitted from a backlight source, thereby displaying an image. If a color filter is added, a color image can be displayed.
The backlight module 100 may be a direct type backlight module or a side-in type backlight module, and the direct type backlight module may have a larger number of light sources than the side-in type backlight module, so as to improve backlight brightness. In the direct type backlight module, a lamp panel or a lamp bar is generally used as a backlight source. The lamp panel is provided with a plurality of light sources in an array, the lamp bars are in a strip shape, and the light sources are arranged in a row. The light source can be a light emitting diode (Light Emitting Diode, short for LED), a Mini LED (Mini Light Emitting Diode, short for Mini LED) or even a Micro LED (Micro Light Emitting Diode, short for Micro LED). The LED has the advantages of high luminous brightness, low energy consumption, environmental protection and the like, the Mini LED and the Micro LED are specifically LED chips, the sizes of the Micro LED and the Micro LED are far smaller than those of the LED, the sizes of the Micro LED are smaller than those of the Mini LED, the sizes of the Mini LED are smaller than 500 mu m, generally smaller than 200 mu m, and the sizes of the Micro LED are smaller than 100 mu m. And when the light sources adopt Mini LEDs and Micro LEDs, more light sources can be arranged on the lamp panel with the same area.
In order to improve the contrast of the display image, obtain lower dark field brightness, realize high dynamic range image display, and carry out Local Dimming (LD) on the backlight module according to the display image, the technology is generated. Each light source on the backlight module is divided into a plurality of subareas, and when the image is displayed, the brightness of each subarea of the backlight module is correspondingly adjusted in cooperation with the brightness distribution of the display image, so that higher image contrast can be obtained, and the display effect is optimized. The finer the area dimming, and the finer the display image.
The dimming technology is mainly divided into analog dimming and digital dimming, wherein the analog dimming is to adjust the brightness of a light source by changing the current value of the light source; digital dimming is to adjust the brightness of a light source by changing the on/off time of the current of the light source, i.e. pulse width modulation (Pulse Width Modulation, PWM for short). The current display device generally adopts analog dimming, and when the brightness of a light source is adjusted, the current of the whole backlight module can only be changed, so that the brightness of a display image is changed as a whole. The current driving chip has the defect of insufficient current adjustment precision, the minimum adjustment range is about 0.5 mA-1 mA, and the variation range of the light source is 10 nit-30 nit. When the brightness of a local area in the picture changes, the brightness of the whole picture also changes due to the change of the driving current of the whole backlight, and the display effect is affected.
In view of the above, the embodiments of the present invention provide a driving method of a display device, which uses an analog-digital hybrid dimming technology, so that when brightness changes in a local area of a display image, brightness of other areas except the local area remains unchanged, thereby achieving a better image display effect.
Fig. 2 is a flowchart of a driving method of a display device according to an embodiment of the invention.
As shown in fig. 2, a driving method of a display device according to an embodiment of the present invention includes:
s10, in the image display process, when the brightness change of the display image is generated in a local area, determining the first brightness of the current display image;
s20, determining a first driving current corresponding to the first brightness according to the first brightness and a relation between the predetermined brightness and the driving current;
s30, adjusting the duty ratio of the first driving current of each partition in the backlight module corresponding to other areas except the local area of the display image;
and S40, driving the light sources of each partition to emit light by adopting the adjusted first driving current and the duty ratio so as to keep the brightness of the display image in other areas unchanged.
The first brightness is the average brightness of the display image after brightness change is generated in the local area. It should be noted that, in the embodiment of the present invention, the average brightness of the display image may refer to the average brightness level APL of the display image. For example, the luminance gradation of the display image may be 0 to 255, and the APL may be 0 to 255 accordingly.
The generation of a brightness change in the local area of the display image may be such that the image content changes during the display of the image, so that the currently displayed image frame generates a brightness change in the local area relative to the previous frame image. In the related art, if the brightness of the display image changes in a local area, the driving current of the backlight module is generally changed correspondingly by adopting analog dimming, so that the brightness of the whole backlight module is changed accordingly, and the brightness of the whole display image is also changed accordingly.
When the brightness change occurs in the local area of the display image by adopting the analog and digital mixed dimming technology, the embodiment of the invention compensates the duty ratio of the driving current of the corresponding subareas of other areas except the local area, so that the brightness of the other areas is kept unchanged.
Specifically, when the brightness change of the display image occurs in the local area, the average brightness (i.e., the first brightness) of the display image after the brightness change can be determined, and then the driving current corresponding to the current first brightness is determined according to the known correspondence between the brightness and the driving current. After the driving current is determined, the duty ratio of the driving current of each partition of the backlight module corresponding to the other areas except the local area with the brightness change is correspondingly compensated, so that when the driving current with the adjusted duty ratio is adopted to drive the light source to emit light in the other areas except the local area, the brightness of the display image in the other areas except the local area can not be changed, and better display effect can be achieved.
In the display device provided by the embodiment of the invention, the light-emitting diode device is used as a backlight source, and the emergent rays of the backlight module provide backlight for the display panel. The average brightness of the display image refers to the average brightness of the display screen after the backlight is modulated by the display panel, so that the average brightness of the display image is not equal to the average brightness of the backlight module, but a positive correlation relationship exists, that is, when the brightness of the display image is large, the brightness of the backlight module is relatively large, and when the brightness of the display image is small, the brightness of the backlight module is relatively small.
The light emitting diode is a current type driving device, when brightness change occurs in a local area of a display image, in order to achieve a better display effect, the backlight module usually also performs corresponding brightness adjustment to match with brightness change of the display image, and at this time, the driving current of the light emitting diode needs to be adjusted. In the embodiment of the invention, when the brightness of the display image is changed, the driving current value of the backlight module needs to be changed, so that the brightness change trend of the backlight module is consistent with the brightness change trend of the display image, and the process is the analog dimming. Meanwhile, the duty ratio of the driving current of the backlight module corresponding to the positions of the other areas except the local area is also required to be compensated, and the process is the digital dimming, so that the backlight brightness of the other areas is not changed along with the change of the backlight brightness of the local area.
FIG. 3 is a graph showing the relationship between the driving current and the relative brightness according to the embodiment of the present invention.
As shown in fig. 3, the display device determines a relationship between the driving current and the relative brightness at the time of shipment, and the correspondence is cured in a program of the display device, and the driving current can be automatically determined according to the brightness to drive the backlight module when displaying an image. In the embodiment of the invention, when the average brightness of the display image is known, the driving current of the backlight module can be determined according to the relation curve between the driving current and the relative brightness shown in fig. 3. In practical applications, the known relationship between the driving current and the relative brightness of the display device may be different from that shown in fig. 3, and the embodiment of the present invention is only illustrated by the relationship shown in fig. 3, and the relationship between the driving current and the relative brightness is not limited.
As can be seen from fig. 3, the driving current of the backlight module and the relative brightness of the display image are positively correlated, the relative brightness has a certain corresponding relationship with the average brightness of the display image, and when the display images are at different average brightness, the driving current of the backlight module can be determined according to the curves of the driving current and the relative brightness.
For example, the relative brightness achieved when driving the backlight module with a driving current of 5mA is 100%; the relative brightness achieved when the backlight module was driven with a driving current of 20mA was 350%.
Fig. 4 is a graph showing a relationship between a driving current and a driving voltage according to an embodiment of the present invention.
As can be seen from fig. 4, the driving current and the driving voltage of the backlight module are positively correlated. For example, when the driving current is 5mA, the driving voltage is 5.55V; when the driving current was 20mA, the driving voltage was 6.15V. The power of the backlight module is also in positive correlation with the driving current.
If a scene of displaying an all-white field picture is taken as an example, when the backlight module is driven to emit light by using a driving current of 5mA, a duty ratio of 100% and a driving current of 20mA and a duty ratio of 25% respectively, the effect achieved theoretically is consistent because the effective current values of the driving current and the duty ratio are both 5 mA.
As can be seen from the relationship between the driving current and the relative brightness shown in fig. 3, the driving current corresponds to 100% relative brightness when the driving current is 5mA, and the driving current corresponds to 350% relative brightness when the driving current is 20 mA. The driving current of the backlight module is increased from 5mA to 20mA, and the relative brightness is increased from 100% to 350%; i.e. the drive current increases by a factor of 4 and the relative brightness increases by a factor of only 3.5. That is, the luminous efficiency is improved by (4-3.5)/4=12.5% with a driving current of 5mA compared with a driving current of 20 mA.
As can be seen from the relationship between the driving current and the driving voltage shown in fig. 4, the driving voltage is 5.55V when the driving current is 5mA, and the power is 5ma×5.55v=27.75 mW; the corresponding driving voltage was 6.15V at a driving current of 20mA, and the power was 20ma×6.15v=123 mW. The driving current of the backlight module is increased from 5mA to 20mA, and the power is increased from 27.75mW to 123mW; i.e. the drive current increases by a factor of 4 and the power increases by a factor of 4.43. That is to say a power reduction of (4.43-4)/4.43=9.7% with a drive current of 5mA compared to a drive current of 20 mA.
On the premise of consistent light-emitting effect, the driving current with the current value of 5mA and the duty ratio of 100% is adopted to drive the backlight module by the driving current with the current value of 20mA and the duty ratio of 25%, so that the light-emitting efficiency is improved by 14%, and the power is reduced by 9.7%. Therefore, when the embodiment of the invention is applied to a scene that the driving current is reduced from large, the effects of improving the luminous efficiency and reducing the power consumption can be achieved.
If the driving current of the backlight module before the brightness of the local area of the display image is referred to as the second driving current and the driving current of the backlight module after the brightness of the local area of the display image is referred to as the first driving current, the driving method provided by the embodiment of the invention is especially suitable for an application scene that the first driving current is smaller than the second driving current.
In practical application, in order to ensure that the backlight module does not exceed the maximum power, when the APL of the display image is large, the backlight module is driven by adopting smaller driving current; when the APL of the display image is smaller, the backlight module is driven by adopting larger driving current.
The method of compensating the duty ratio of the driving current so that the brightness of the display image remains unchanged except for the brightness of the partial region will be described below.
Fig. 5 is a second flowchart of a driving method of a display device according to an embodiment of the invention.
As shown in fig. 5, in the step S30, the adjustment of the duty ratio of the first driving current of each partition in the backlight module corresponding to the other area except the partial area of the display image specifically includes:
s301, determining a second brightness of the display image and a duty ratio of a second driving current;
S302, determining the duty ratio of the first driving current according to the second brightness, the duty ratio of the second driving current and the first brightness.
The second brightness is the average brightness before the brightness change of the display image in the local area, and the second driving current is the driving current corresponding to the second brightness.
The embodiment of the invention aims to keep the backlight brightness of other areas except for the local area generating brightness variation unchanged, and the luminous brightness is directly related to the current value of the driving current and also related to the duty ratio of the driving current. When the brightness of the display image changes, the driving current value is determined according to the corresponding relation between the brightness and the driving current, so that the embodiment of the invention adjusts the brightness by the duty ratio of the driving current in other areas.
Specifically, the embodiment of the invention determines the duty ratio of the driving current corresponding to the other areas except the local area after the local area of the display image is changed according to the average brightness of the backlight module before and after the local area of the display image is changed and the duty ratio of the driving current of the backlight module before the local area of the display image is changed.
In order to facilitate distinguishing between the driving current before and after the brightness change and the brightness corresponding to the driving current, the embodiment of the invention refers to the average brightness after the brightness change of the local area of the display image as first brightness, and refers to the driving current corresponding to the first brightness as first driving current; the average luminance before the luminance change occurs in the partial region of the display image is referred to as a second luminance, and the driving current corresponding to the second luminance is referred to as a second driving current.
In an embodiment of the present invention, the duty cycle of the first driving current may be determined using the following formula:
D 1 ＝D 2 (L 2 /L 1 )；
wherein D is 1 Represents the duty cycle of the first driving current, D 2 Representing the duty cycle of the second drive current, L 1 Represents a first brightness, L 2 Representing a second brightness.
In particular, the current display image is an image of the previous frame display image after the local brightness change, and the average brightness (L 2 ) And a drive current duty ratio (D 2 ) As a known parameter, the average luminance (L 1 ) In the case of the drive current determination, the correspondence between the drive current and the relative brightness according to FIG. 3 can be obtained, thus in L1, L 2 And D 2 In the known case, the duty ratio (D 1 )。
For example, assuming that the driving current of the backlight module before the brightness change of the local area is generated is 20mA (i.e., the second driving current is 20 mA), the duty ratio is 25% (i.e., d2=25%), and the relative brightness of the corresponding display image is 350%; the driving current of the backlight module after the brightness change of the local area of the display image is 5mA (namely, the first driving current is 5 mA), and the relative brightness of the corresponding display image is 100%. From the above formula, it can be calculated that the duty ratio d1=350% ×25%/100% =87 5% of the driving current is in the other region than the partial region where the luminance is changed.
Because the driving current of the backlight module is not in linear relation with the luminous brightness, the luminous efficiency is higher when the driving current is smaller, and therefore, the luminous efficiency can be improved and the power consumption can be reduced when the driving current of the backlight module is changed from large to small.
In the above step S301, when determining the average luminance of the display image, the average value of the luminance of each partition in the display image may be taken as the average luminance of the display image.
In a specific implementation, the brightness of each partition in the backlight module is determined according to the brightness distribution of the display image, so that when the display image is divided according to the partition corresponding to the backlight module, the average value of the brightness of the display image in each partition is the average brightness.
For example, the light source in the backlight module is divided into z 1 、z 2 、z 3 、z 4 Four partitions, the display image corresponding to the first partition z 1 The brightness of the area is l 1 The display image corresponds to the second zone z 2 The brightness of the area is l 2 The display image corresponds to zone z 3 The brightness of the area is l 3 The display image corresponds to zone z 4 The brightness of the area is l 4 Then the average brightness of the displayed image at this time is l= (L) 1 +l 2 +l 3 +l 4 )/4。
In practical applications, before the brightness of the local area of the display image changes, the average brightness of the display image and the duty ratio of the driving current are both known, so that the current driving current and the duty ratio of the driving current can be determined according to the brightness of the image to be displayed after the brightness of the display image changes in the local area.
In the partial region where the luminance change occurs, the ratio of the luminance of the partial image corresponding to a certain partition in the display image to the maximum luminance may be set as the duty ratio of the first driving current of the partition.
For example, the light source in the backlight module is divided into z 1 ～z 4 Four partitions, if partition z 1 When the brightness of the display image in the region becomes 100 gray scale and the maximum gray scale is 255, then in the driving region z 1 The duty cycle of the drive current of (100/255) ×100+.39.2%. The duty cycle of the driving current for the other partitions generating the brightness variation may be determined according to the above-described method.
Since the light source of the backlight module is divided into a plurality of partitions, the partitions of the backlight module corresponding to the local area where the brightness of the display image changes may not be one, and similarly, other areas except for the local area may also correspond to the plurality of partitions of the backlight module, so that the driving current and the duty ratio of each partition in the backlight module may be determined sequentially according to the above method, and after the driving currents and the duty ratios of all the partitions are determined, the light source in each partition is driven to emit light by adopting the same driving current and the duty ratio corresponding to each partition.
The method of digital-analog hybrid dimming of the present invention will be specifically described in two examples.
FIG. 6 is a schematic diagram of a display image according to an embodiment of the present invention; fig. 7 is a second schematic diagram of a display image according to an embodiment of the invention. Fig. 6 shows a display image before the brightness change is not generated, and fig. 7 shows a display image after the brightness change is generated in the B region.
When the display image is changed from fig. 6 to fig. 7, the luminance change occurs only in the B region, and in the display images shown in fig. 6 and fig. 7, the B region indicates a partial region where the luminance change occurs, and the a region indicates other regions than the partial region.
The light source in the backlight module is divided into z 1 ～z 9 Nine partitions, correspondingly, the display image can also be regarded as being divided to correspond to z 1 ～z 9 Nine parts, wherein the B area corresponds to zone z 5 Region A corresponds to z 1 ～z 4 Z 6 ～z 9 。
When the display image is changed from fig. 6 to fig. 7, since only the B region has a brightness change, it is necessary to determine the average brightness L of the display image shown in fig. 7 in order to maintain the brightness of the display image in the a region unchanged and to improve the contrast of the screen 1 Average brightness L of the display image shown in FIG. 6 2 The display image shown in FIG. 6 is shown in each zone z 1 ～z 9 And its duty cycle and D 21 ～D 29 Thereby determining each partition z when the display image becomes fig. 7 1 ～z 9 Is set to a duty cycle D 11 ～D 19 。
Wherein, before the brightness change occurs in the B region of the display image (as shown in FIG. 6), the average brightness L of the display image 2 For each zone z 1 ～z 9 Average value of brightness of corresponding partial display image, the average brightness L 2 And each partition z 1 ～z 9 Drive current value I of (2) 2 Each partition z 1 ～z 9 Duty ratio D of the driving current of (2) 21 ～D 29 Are known parameters. After the change in the B region of the display image (as shown in FIG. 7), the display image is divided into regions z 1 ～z 9 Luminance input of the corresponding partial display image, average luminance L of the display image 1 For each zone z 1 ～z 9 The average value of the brightness of the corresponding partial display image; the driving current I of the backlight module at this time can be determined according to the corresponding relationship between the driving current and the brightness shown in FIG. 3 1 For each partition z, the backlight module 1 ～z 9 The driving currents of (a) are all I 1 However, the duty ratio of the driving current for each partition needs to be adjusted so that the area a maintains the original brightness after the brightness change of the display image in the area B.
For partition z 1 ～z 4 And z 6 ～z 9 The duty ratio of the driving current of any one partition is determined in the same way as that of the partition, so as to partition z 1 An example is described. The average brightness of the display image when the image shown in fig. 6 is displayed is L 2 The driving current of each partition is I 2 Partition z 1 The duty ratio of the driving current of (2) is D 21 The method comprises the steps of carrying out a first treatment on the surface of the Since the image shown in FIG. 6 is an image that has been displayed before changing to the image of FIG. 7, L 2 、I 2 、D 21 Are known parameters. When the display image shown in fig. 6 is changed to the display image shown in fig. 7, the luminance of the partial display image corresponding to each partition is inputted, and thus the average luminance L of the display image shown in fig. 7 can be obtained 1 According to L 1 The relation curve shown in FIG. 3 determines that the driving current of the backlight module is I 1 . From this, the partition z can be calculated according to the above 1 Duty ratio D of the driving current of (2) 11 ＝D 21 (L 2 /L 1 ). The partition z can be calculated by the same method 2 ～z 4 Z 6 ～z 9 Duty ratio D of the driving current of (2) 12 ～D 14 D (D) 16 ～D 19 。
And for partition z 5 For determining the duty ratio D of the driving current of the partition 15 Can be based on partition z 5 The ratio of the brightness of the corresponding partial display image to the maximum brightness is determined.
Thus, the driving current I of the backlight module can be obtained when the image shown in FIG. 7 is displayed 1 And each partition z 1 ～z 9 Duty ratio D of the driving current of (2) 11 ～D 19 Then, when the image shown in FIG. 7 is displayed, the backlight module adopts the driving current I 1 And the duty ratio of the driving current of each partition is D 11 ～D 19 Driving is performed so that the display image of the B region reaches the corresponding brightness, while the display brightness of the a region remains unchanged.
FIG. 8 is a third schematic diagram of a display image according to an embodiment of the present invention; fig. 9 is a schematic diagram of a display image according to an embodiment of the present invention. Fig. 8 shows a display image before the brightness change is not generated, and fig. 9 shows a display image after the brightness change is generated in the B region.
When the display image is changed from fig. 8 to fig. 9, the luminance change occurs only in the B region, and in the display images shown in fig. 8 and 9, the B region indicates a partial region where the luminance change occurs, and the a region indicates other regions than the partial region.
The light source in the backlight module is divided into z 1 ～z 4 Four partitions, correspondingly, the display image can also be regarded as being divided to correspond to z 1 ～z 4 Four parts, wherein the B region corresponds to zone z 2 And z 4 Region A corresponds to z 1 And z 3 。
Before the display image is changed from fig. 8 to fig. 9, the display image shown in fig. 8 is an already displayed image, and thus the average luminance L of the display image 2 Drive current I of backlight module 2 Each partition z 1 ～z 4 Duty ratio D of the driving current of (2) 21 ～D 24 Is a known parameter.
When the display image is changed from fig. 8 to fig. 9, the display image corresponds to the partition z 2 And z 4 Partially produces brightness variation and corresponds to zone z 2 And z 4 The degree of brightness change of (c) is also different. When the display image is changed from fig. 8 to fig. 9, the display image corresponds to the zone z 1 ～z 4 The brightness of the display image is l respectively 11 、l 12 、l 13 、l 14 Then the average luminance l1= (L) of the display image after the luminance change is generated 11 +l 12 +l 13 +l 14 ) According to the relation shown in FIG. 3, the driving current of the backlight module can be determined as I 1 。
Partition z 2 Duty ratio D of the driving current of (2) 12 Can be based on partition z 2 Calculating the proportion of the brightness of the light source to the maximum brightness; partition z 4 Duty ratio D of the driving current of (2) 14 Can be based on partition z 4 Is bright of (2)The ratio of the degree to the maximum brightness is calculated. Partition z 1 The duty cycle of the drive current of (2) can be obtained according to the above formula 11 ＝D 21 (L 2 /L 1 ) The method comprises the steps of carrying out a first treatment on the surface of the Partition z 3 The duty cycle of the drive current of (2) can be obtained according to the above formula 13 ＝D 23 (L 2 /L 1 )。
Therefore, the duty ratio of the driving current of the backlight module and the driving current of each partition when the display image is changed from fig. 8 to fig. 9 can be determined, and the light sources of each partition are driven according to the determined driving current and the determined duty ratio, so that the brightness of the area A is kept unchanged when the brightness of the area B is changed.
The embodiment of the invention only uses nine or four partitions of the backlight module for illustration, but does not limit the number of partitions contained in the backlight module, and in practical application, the driving current and the duty ratio of the backlight module can be adjusted according to the principle so as to optimize the image display effect.
In another aspect of the embodiments of the present invention, a display device is provided, and fig. 1 is a schematic cross-sectional structure of the display device provided in the embodiment of the present invention.
As shown in fig. 1, the display device includes: a backlight module 100 and a display panel 200. The display panel 200 is located at the light emitting side of the backlight module 100. The backlight module 100 is used for providing backlight, and the display panel 200 is used for displaying images.
Fig. 10 is a schematic perspective view of a display device according to an embodiment of the invention.
As shown in fig. 10, the backlight module includes: a back plate 1, a backlight 2, a diffusion plate 3 and an optical film 4.
The backboard 1 is positioned at the bottom of the backlight module and has the functions of supporting and bearing. The back plate 1 is typically a square structure, the shape of which is adapted to the shape of the display device when applied to a shaped display device. The back plate 1 includes a top side, a bottom side, a left side, and a right side. Wherein the sky side is relative with the earth side, and left side is relative with the right side, and the sky side links to each other with one end of left side and one side of right side respectively, and the earth side links to each other with the other end of left side and the other end of right side respectively.
The backboard 1 is made of aluminum, iron, aluminum alloy or iron alloy and the like. The back plate 1 is used for supporting the backlight source 2, and supporting and fixing the edge positions of the diffusion plate 3, the optical membrane 4 and other components, and the back plate 1 also plays a role in heat dissipation of the backlight source 2.
In the embodiment of the invention, the backlight module is preferably a direct type backlight module, so that more light sources can be arranged, and the backlight brightness is improved.
In some embodiments, the backlight 2 may be a light bar or a light board. In the embodiment of the invention, the backlight source 2 adopts a lamp panel as an example to specifically describe the structure of the backlight source.
The lamp panel is positioned on the backboard 1. Generally, the lamp panel may have a square or rectangular shape as a whole. A plurality of lamp panels can be arranged according to the size of the display device, and backlight is provided between the lamp panels in a splicing mode.
The diffusion plate 3 is located on the light emitting side of the backlight 2 and is spaced apart from the backlight 2 by a certain distance. The distance is set so that light can be sufficiently mixed between the light sources. The diffusion plate 3 is used for scattering incident light, so that the light passing through the diffusion plate 3 is more uniform.
The diffusion plate 3 is provided with scattering particle materials, and light rays are incident on the scattering particle materials and are continuously refracted and reflected, so that the effect of scattering the light rays is achieved, and the effect of homogenizing the light is achieved. The thickness of the diffusion plate is usually set to 0.5mm-3mm, and the larger the thickness of the diffusion plate is, the larger the haze is, and the better the uniformity effect is.
The diffusion plate 3 may be generally manufactured by an extrusion process, and the diffusion plate 3 is made of at least one material selected from polymethyl methacrylate PMMA, polycarbonate PC, polystyrene PS, and polypropylene PP.
In an embodiment of the invention, the backlight 2 may be used to emit blue light. At this time, the diffusion plate 3 may be a quantum dot diffusion plate for realizing color conversion and diffusion functions.
The optical film 4 is located on the side of the diffusion plate 3 facing away from the backlight 2. The optical film 4 is sized to fit the display device and is slightly smaller than the display device, and is typically rectangular or square.
In specific implementation, the optical film 4 includes one or a combination of several of a fluorescent film, a quantum film, a prism sheet, a brightness enhancement film, and the like, and is not limited herein.
Fig. 11 is a schematic top view of a lamp panel according to an embodiment of the present invention, and fig. 12 is a schematic cross-sectional view of a lamp panel according to an embodiment of the present invention.
As shown in fig. 11 and 12, in the embodiment of the present invention, when the backlight 2 employs a lamp panel, the backlight includes a circuit board 21, a light source 22, and a driving chip 23.
The circuit board 21 is located above the back plate 1, and the shape of the circuit board 21 is the same as the overall shape of the lamp panel. In general, the circuit board 21 has a plate shape, and is rectangular or square in its entirety.
The circuit board 21 may be a printed circuit board (Printed Circuit Board, abbreviated as PCB). The circuit board 21 may be a single-layer board, a double-layer board, or a multi-layer board according to actual needs, and is not limited herein.
As shown in fig. 12, the circuit board 21 specifically includes: a substrate 211, a wiring layer 212 and a solder resist layer 213.
The substrate 211 has a load-bearing function, is the same shape and size as a circuit board, and may be generally rectangular or square. The substrate 211 may be BT, FR4, aluminum, glass, or a flexible material, and is not limited herein, and is selected according to the application scenario.
The circuit layer 212 is disposed on the substrate and is used for transmitting driving signals. The circuit layer 212 may be formed by patterning after copper is coated on the substrate 211.
The solder mask 213 is located on a side of the circuit layer 212 away from the substrate 211, and is used for insulating and protecting the circuit layer 212. The solder mask 213 is typically coated with an insulating material on the surface of the circuit layer 212, and the solder mask 213 includes a plurality of windows where pads are exposed for soldering the light source 22 and other components.
The light source 22 is located on the circuit board 21, specifically on a side of the solder mask 213 facing away from the circuit layer 212, and the light source 22 is electrically connected to the circuit layer 212 through the window of the solder mask 213.
In the embodiment of the present invention, the light source 22 may be an LED, a Mini LED or a Micro LED, which is not limited herein.
The driving chip 23 may be bound to a side of the circuit board 21 facing away from the light source 22, or may be bound to a side of the circuit board 21 near the light source 22, which is not limited herein.
The driving chip 23 is used for providing driving signals for the backlight module, so as to drive the light source on the backlight module to emit light.
As shown in fig. 11, the plurality of light sources 22 are divided into a plurality of partitions z, each partition z including at least one light source 22, and the light sources 22 in the same partition z are connected in series with each other. The driving chip 23 is electrically connected to each of the partitions z, respectively, for supplying driving signals to each of the partitions z.
In the embodiment of the invention, the driving chip can adopt a Micro LED driving chip. When the Micro LED driving chip provides driving signals for the backlight module, the driving current values of all the partitions are consistent, but the duty ratios of the driving currents of all the partitions are different, so that the brightness of all the partitions is different.
The driving chip 23 is used for determining the first brightness of the current display image when the display image generates brightness change in the local area in the image display process; determining a first driving current corresponding to the first brightness according to the first brightness and a relation between the predetermined brightness and the driving current; the duty ratio of the first driving current of each partition in the backlight module corresponding to other areas except the local area of the display image is adjusted; and driving the light sources of each partition to emit light by adopting the adjusted first driving current and the duty ratio so as to keep the brightness of the display image in other areas unchanged. The first brightness is the average brightness of the display image after brightness change is generated in the local area.
When the brightness change occurs in the local area of the display image by adopting the analog and digital mixed dimming technology, the embodiment of the invention compensates the duty ratio of the driving current of the corresponding subareas of other areas except the local area, thereby keeping the brightness of the other areas unchanged, improving the contrast of the display image and optimizing the display effect of the image.
The driving chip 23 is specifically configured to determine a second brightness of the display image and a duty ratio of a second driving current; determining the duty ratio of the first driving current according to the second brightness, the duty ratio of the second driving current and the first brightness; the second brightness is the average brightness before the brightness change of the display image in the local area, and the second driving current is the driving current corresponding to the second brightness.
Specifically, the driving chip 23 determines the duty ratio of the first driving current using the following formula:
D 1 ＝D 2 (L 2 /L 1 )；
wherein D is 1 Represents the duty cycle of the first driving current, D 2 Representing the duty cycle of the second drive current, L 1 Represents a first brightness, L 2 Representing a second brightness.
The duty ratio of the driving current of each partition corresponding to the local area where the luminance change occurs can be determined based on the ratio of the luminance of the partition to the maximum luminance. Therefore, when the determined driving current and the duty ratio of the driving current of each partition are adopted to drive the light source of each partition to emit light, the brightness of other areas of the display image except for the local area with the brightness changed can be kept unchanged.
According to a first inventive concept, a driving method of a display device includes: determining a first brightness of a currently displayed image when the displayed image generates brightness variation in a local area in the image display process; determining a first driving current corresponding to the first brightness according to the first brightness and a relation between the predetermined brightness and the driving current; the duty ratio of the first driving current of each partition in the backlight module corresponding to other areas except the local area of the display image is adjusted; and driving the light sources of each partition to emit light by adopting the adjusted first driving current and the duty ratio so as to keep the brightness of the display image in other areas unchanged. The first brightness is the average brightness of the display image after brightness change is generated in the local area.
When brightness change is generated in a local area of a display image by adopting an analog and digital mixed dimming technology, the duty ratio of driving current of corresponding subareas of other areas except the local area is compensated, so that the brightness of the other areas is kept unchanged, the contrast ratio of the display image is improved, and the image display effect is optimized.
According to the second inventive concept, when the driving method of the display device is applied to a scene where the driving current is reduced from large, the effects of improving the light emitting efficiency and reducing the power consumption can be achieved.
According to the third inventive concept, after obtaining the average brightness of the display image, the driving current of the backlight module is determined according to the relation curve of the driving current and the relative brightness.
According to a fourth inventive concept, the duty cycle of the first driving current is determined according to the second luminance, the duty cycle of the second driving current, and the first luminance. The second brightness is the average brightness before the brightness change of the display image in the local area, and the second driving current is the driving current corresponding to the second brightness.
The light emission luminance is directly related to the current value of the driving current, and also to the duty ratio of the driving current. When the brightness of the display image changes, the driving current value is determined according to the corresponding relation between the brightness and the driving current, so that the brightness is adjusted by the duty ratio of the driving current in other areas.
According to a fifth inventive concept, the duty cycle of the first drive current is determined using the following formula:
D 1 ＝D 2 (L 2 /L 1 )；
wherein D is 1 Represents the duty cycle of the first driving current, D 2 Representing the duty cycle of the second drive current, L 1 Represents a first brightness, L 2 Representing a second brightness.
The current display image is an image of the previous frame display image after the luminance change is locally generated, and then the average luminance (L 2 ) And a drive current duty ratio (D 2 ) As a known parameter, the average luminance (L 1 ) In the case of the determination of the driving current, it is possible to obtain from the correspondence of the driving current and the relative brightness,thus at L1, L 2 And D 2 In the known case, the duty ratio (D 1 )。
According to the sixth inventive concept, for a partial region where a luminance variation occurs, a ratio of luminance of a partial image corresponding to a certain partition in a display image to the maximum luminance may be taken as a duty ratio of a first driving current of the partition.
According to the seventh inventive concept, the brightness of each partition in the backlight module is determined according to the brightness distribution of the display image, so that when the display image is divided according to the partition corresponding to the backlight module, the average value of the brightness of the display image in each partition is the average brightness of the display image.
According to an eighth inventive concept, a display device includes: a display panel and a backlight module; the backlight module comprises a plurality of light sources and a driving chip. The plurality of light sources are divided into a plurality of partitions, each partition comprises at least one light source, and the light sources in the same partition are connected in series; the driving chip is electrically connected with each partition and is used for providing driving signals for each partition; the driving chip is used for determining the first brightness of the current display image when the display image generates brightness change in the local area in the image display process; the first brightness is the average brightness of the display image after brightness change is generated in the local area; determining a first driving current corresponding to the first brightness according to the first brightness and a relation between the predetermined brightness and the driving current; the duty ratio of the first driving current of each partition in the backlight module corresponding to the other areas except the local area of the displayed image is adjusted; and driving the light sources of each partition to emit light by adopting the adjusted first driving current and the duty ratio so as to keep the brightness of the display image in other areas unchanged.
According to a ninth inventive concept, the driving chip is specifically configured to determine a second brightness of the display image and a duty ratio of a second driving current; determining the duty ratio of the first driving current according to the second brightness, the duty ratio of the second driving current and the first brightness;
the second brightness is the average brightness before the brightness change of the display image in the local area, and the second driving current is the driving current corresponding to the second brightness;
the driving chip determines the duty cycle of the first driving current using the following formula:
D 1 ＝D 2 (L 2 /L 1 )；
wherein D is 1 Represents the duty cycle of the first driving current, D 2 Representing the duty cycle of the second drive current, L 1 Represents a first brightness, L 2 Representing a second brightness.
According to a tenth inventive concept, the driving chip is a Micro LED driving chip.
While preferred embodiments of the present invention have been described, additional variations and modifications in those embodiments may occur to those skilled in the art once they learn of the basic inventive concepts. It is therefore intended that the following claims be interpreted as including the preferred embodiments and all such alterations and modifications as fall within the scope of the invention.
It will be apparent to those skilled in the art that various modifications and variations can be made to the present invention without departing from the spirit or scope of the invention. Thus, it is intended that the present invention also include such modifications and alterations insofar as they come within the scope of the appended claims or the equivalents thereof.
Claims (10)
1. A driving method of a display device, characterized in that the display device comprises: the backlight module comprises a plurality of light sources and a display panel; the plurality of light sources are divided into a plurality of partitions;
the driving method includes:
determining a first brightness of a currently displayed image when the displayed image generates brightness variation in a local area in the image display process; the first brightness is the average brightness of the display image after brightness change is generated in the local area;
determining a first driving current corresponding to the first brightness according to the first brightness and a relation between the predetermined brightness and the driving current;
the duty ratio of the first driving current of each partition in the backlight module corresponding to the other areas except the local area of the display image is adjusted;
and driving the light sources of each partition to emit light by adopting the adjusted first driving current and the duty ratio so as to keep the brightness of the display image in the other areas unchanged.
2. The driving method according to claim 1, wherein adjusting the duty ratio of the first driving current for each partition in the backlight module corresponding to the other area than the partial area of the display image comprises:
Determining a second brightness of the display image and a duty ratio of a second driving current; the second brightness is the average brightness of the display image before brightness change is generated in the local area, and the second driving current is the driving current corresponding to the second brightness;
and determining the duty ratio of the first driving current according to the second brightness, the duty ratio of the second driving current and the first brightness.
3. The driving method according to claim 2, wherein the first driving current is smaller than the second driving current.
4. The driving method according to claim 1 or 2, wherein the determining the average luminance of the display image includes:
the average value of the brightness of each partition in the display image is taken as the average brightness of the display image.
5. The driving method of claim 4, wherein the duty cycle of the first driving current is determined using the following formula:
D 1 ＝D 2 (L 2 /L 1 )；
wherein D is 1 Represents the duty cycle of the first driving current, D 2 Representing the second driving powerDuty cycle of flow, L 1 Representing the first brightness, L 2 Representing the second brightness.
6. The driving method according to claim 1, wherein determining the duty ratio of the first driving current for each partition in the backlight module corresponding to the partial area includes:
And taking the proportion of the brightness of the partial image corresponding to the subarea in the display image to the maximum brightness as the duty ratio of the first driving current of the subarea.
7. The driving method according to claim 1, wherein the predetermined relationship of luminance and driving current satisfies a known driving current-luminance relationship of the display device.
8. A display device, comprising:
a display panel for displaying an image;
the backlight module is positioned on the light incident side of the display panel and is used for providing backlight;
wherein, backlight unit includes:
the light source is divided into a plurality of subareas, each subarea comprises at least one light source, and the light sources in the same subarea are connected in series;
the driving chip is electrically connected with each partition and is used for providing driving signals for each partition;
the driving chip is used for determining the first brightness of the current display image when the display image generates brightness change in the local area in the image display process; the first brightness is the average brightness of the display image after brightness change is generated in the local area; determining a first driving current corresponding to the first brightness according to the first brightness and a relation between the predetermined brightness and the driving current; the duty ratio of the first driving current of each partition in the backlight module corresponding to the areas except the local area of the displayed image is adjusted; and driving the light sources of each partition to emit light by adopting the adjusted first driving current and the duty ratio so as to keep the brightness of the display image in the other areas unchanged.
9. The display device of claim 8, wherein the driving chip is specifically configured to determine a second brightness of the display image and a duty cycle of the second driving current; determining the duty ratio of the first driving current according to the second brightness, the duty ratio of the second driving current and the first brightness;
the second brightness is the average brightness of the display image before brightness change occurs in the local area, and the second driving current is the driving current corresponding to the second brightness;
the driving chip determines the duty ratio of the first driving current by adopting the following formula:
D 1 ＝D 2 (L 2 /L 1 )；
wherein D is 1 Represents the duty cycle of the first driving current, D 2 Representing the duty cycle of the second driving current, L 1 Representing the first brightness, L 2 Representing the second brightness.
10. The display device of claim 9, wherein the driver chip is a Micro LED driver chip.
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| CN202210669073.4A CN117275419A (en) | 2022-06-14 | 2022-06-14 | Driving method of display device and display device |
| PCT/CN2023/084608 WO2023236632A1 (en) | 2022-06-08 | 2023-03-29 | Driving method for display device and display device |
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| CN202210669073.4A CN117275419A (en) | 2022-06-14 | 2022-06-14 | Driving method of display device and display device |
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| Country | Link |
|---|---|
| CN (1) | CN117275419A (en) |
-
2022
- 2022-06-14 CN CN202210669073.4A patent/CN117275419A/en active Pending
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