CN112259052B - Brightness adjusting method, brightness adjusting device and display device - Google Patents
Brightness adjusting method, brightness adjusting device and display device Download PDFInfo
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Abstract
The invention provides a brightness adjusting method, a brightness adjusting device and a display device, and relates to the technical field of display. The method comprises the steps of obtaining the minimum display brightness value of a display panel in one frame time and the display brightness value of a target moment in one frame time; determining a duty ratio coefficient corresponding to the target moment according to the minimum display brightness value and the display brightness value of the target moment; determining a target duty ratio of the pulse width modulation signal at a target moment according to the duty ratio coefficient and the original duty ratio of the pulse width modulation signal; and sending the target duty ratio to the backlight module so that the backlight module adjusts the pulse width modulation signal corresponding to the target moment according to the target duty ratio. By determining the target duty ratio of the target time and adjusting the pulse width modulation signal of the target time according to the target duty ratio, the display brightness values penetrating through the display panel within one frame time can be kept consistent, the flicker phenomenon is eliminated, and the process of improving the flicker of the display panel is simple.
Description
Technical Field
The present invention relates to the field of display technologies, and in particular, to a brightness adjustment method, a brightness adjustment device, and a display device.
Background
With the development of display technology, how to reduce the power consumption of a display device is a concern, and in order to reduce the power consumption, the reduction of the refresh frequency of a display panel can be realized, but after the refresh frequency is reduced, flickers (flickers) are easily caused to the display panel.
At present, in order to improve flickers of a display panel at a low refresh frequency, improvement and optimization are generally made from the aspects of materials and processes for manufacturing the display panel.
However, improving flicker of the display panel at a low refresh rate by improving the materials and processes of the display panel usually requires a long test time, and the improvement process is complicated, and when the refresh rate is further reduced, for example, the refresh rate is reduced to 20Hz, the display panel still has a significant flicker phenomenon even if adjusted in terms of materials and processes.
Disclosure of Invention
The invention provides a brightness adjusting method, a brightness adjusting device and a display device, which are used for solving the problems that the existing display panel flicker is improved in the aspects of materials and processes under the low refreshing frequency, the process is complex, and the display panel still flickers when the refreshing frequency is further reduced.
In order to solve the above problems, the present invention discloses a brightness adjusting method, which is applied to a backlight module, and the method comprises:
acquiring a minimum display brightness value of a display panel in a frame time and a display brightness value of a target moment in the frame time; the target time is any time in the frame time;
determining a duty ratio coefficient corresponding to the target moment according to the minimum display brightness value and the display brightness value of the target moment;
determining a target duty ratio of the pulse width modulation signal at the target moment according to the duty ratio coefficient and an original duty ratio of the pulse width modulation signal;
and sending the target duty ratio to the backlight module so that the backlight module adjusts the pulse width modulation signal corresponding to the target moment according to the target duty ratio.
Optionally, the step of determining the duty ratio coefficient corresponding to the target time according to the minimum display brightness value and the display brightness value at the target time includes:
and determining the ratio of the minimum display brightness value to the display brightness value at the target moment as a duty ratio coefficient corresponding to the target moment.
Optionally, the step of determining the target duty cycle of the pwm signal at the target time according to the duty cycle coefficient and the original duty cycle of the pwm signal includes:
and determining the product of the duty ratio coefficient and the original duty ratio of the pulse width modulation signal as the target duty ratio of the pulse width modulation signal at the target moment.
Optionally, after the step of obtaining the minimum display brightness value of the display panel in one frame time and the display brightness value of the display panel at the target time in the one frame time, the method further includes:
determining a target display brightness value which needs to be reached by the display panel at each moment in the frame time;
determining a target maximum backlight brightness value of the backlight module according to the target display brightness value, the original maximum backlight brightness value of the backlight module and the minimum display brightness value;
and sending the target maximum backlight brightness value to the backlight module so that the backlight module emits light according to the target maximum backlight brightness value.
Optionally, the step of determining the target maximum backlight brightness value of the backlight module according to the target display brightness value, the original maximum backlight brightness value of the backlight module and the minimum display brightness value includes:
calculating the product of the target display brightness value and the original maximum backlight brightness value of the backlight module;
and determining the ratio of the product to the minimum display brightness value as a target maximum backlight brightness value of the backlight module.
In order to solve the above problem, the present invention also discloses a brightness adjusting device, which is applied to a backlight module, the device comprising:
the display brightness value acquisition module is configured to acquire a minimum display brightness value of a display panel in one frame time and a display brightness value of a target moment in the one frame time; the target time is any time in the frame time;
a duty ratio coefficient determining module configured to determine a duty ratio coefficient corresponding to the target time according to the minimum display brightness value and the display brightness value of the target time;
a target duty cycle determination module configured to determine a target duty cycle of the pulse width modulation signal at the target time according to the duty cycle coefficient and an original duty cycle of the pulse width modulation signal;
and the target duty ratio sending module is configured to send the target duty ratio to the backlight module so that the backlight module adjusts the pulse width modulation signal corresponding to the target moment according to the target duty ratio.
Optionally, the duty ratio coefficient determining module includes:
a duty ratio determining submodule configured to determine a ratio of the minimum display brightness value to the display brightness value at the target time as a duty ratio corresponding to the target time.
Optionally, the target duty cycle determining module includes:
a target duty cycle determination submodule configured to determine a product of the duty cycle coefficient and an original duty cycle of a pulse width modulation signal as a target duty cycle of the pulse width modulation signal at the target time.
Optionally, the brightness adjusting device further includes:
a target display brightness value determining module configured to determine a target display brightness value that the display panel needs to reach at each moment within the one frame time;
a target maximum backlight brightness value determining module configured to determine a target maximum backlight brightness value of the backlight module according to the target display brightness value, an original maximum backlight brightness value of the backlight module, and the minimum display brightness value;
and the target maximum backlight brightness value sending module is configured to send the target maximum backlight brightness value to the backlight module so that the backlight module emits light according to the target maximum backlight brightness value.
Optionally, the target maximum backlight brightness value determining module includes:
a product calculation sub-module configured to calculate a product of the target display brightness value and an original maximum backlight brightness value of the backlight module;
and the target maximum backlight brightness value determining submodule is configured to determine the ratio of the product to the minimum display brightness value as the target maximum backlight brightness value of the backlight module.
In order to solve the above problem, the present invention further discloses a display device, including the above brightness adjusting device.
Optionally, the display device further includes a backlight module and a display panel, and the display panel is disposed on a light-emitting side of the backlight module;
the backlight module comprises a backlight driving chip and a backlight substrate, wherein the backlight driving chip is configured to adjust the pulse width modulation signal corresponding to the target time according to the target duty ratio and control the backlight brightness value of light rays actually emitted by the backlight substrate according to the adjusted pulse width modulation signal.
Compared with the prior art, the invention has the following advantages:
in the embodiment of the invention, the minimum display brightness value of the display panel in one frame time and the display brightness value of the target moment in one frame time are obtained; the target time is any time within one frame time; determining a duty ratio coefficient corresponding to the target moment according to the minimum display brightness value and the display brightness value of the target moment; determining a target duty ratio of the pulse width modulation signal at a target moment according to the duty ratio coefficient and the original duty ratio of the pulse width modulation signal; and sending the target duty ratio to the backlight module so that the backlight module adjusts the pulse width modulation signal corresponding to the target moment according to the target duty ratio. The target duty ratio of the pulse width modulation signal at the target time is determined according to the minimum display brightness value and the display brightness value of the display panel at the target time in one frame time and the original duty ratio of the pulse width modulation signal, the pulse width modulation signal at the target time is adjusted according to the target duty ratio, the adjusted pulse width modulation signal can change the backlight brightness value of light which is actually irradiated on the display panel by the backlight module, the display brightness corresponding to each time of the display panel in one frame time can be kept consistent, the flicker phenomenon of the display panel is eliminated, in addition, the backlight brightness value of the light emitted by the backlight module is adjusted through the duty ratio, the flicker of the display panel is improved, the improvement process is simple, and long test time is not needed.
Drawings
Fig. 1 shows a flow chart of a brightness adjustment method according to an embodiment of the invention;
FIG. 2 is a diagram illustrating the collection of luminance variation curves of a display panel according to an embodiment of the present invention;
FIG. 3 is a graph showing a luminance profile over a frame time;
FIG. 4 is a diagram showing a luminance change curve in one frame time after being converted into a digital signal;
FIG. 5 is a flow chart of another brightness adjustment method according to an embodiment of the present invention;
FIG. 6 is a waveform diagram illustrating the duty cycle of a PWM signal corresponding to the original duty cycle;
FIG. 7 is a waveform diagram illustrating a duty cycle of a PWM signal at a target duty cycle;
FIG. 8 is a schematic diagram showing a luminance variation curve of an unmodulated PWM signal in a continuous multi-frame time after the PWM signal is applied to a backlight module;
FIG. 9 is a schematic diagram showing a luminance variation curve of the display panel in a continuous multi-frame time after the adjusted PWM signal is applied to the backlight module;
fig. 10 is a block diagram showing a structure of a luminance adjusting apparatus according to an embodiment of the present invention.
Detailed Description
In order to make the aforementioned objects, features and advantages of the present invention comprehensible, embodiments accompanied with figures are described in further detail below.
Example one
Referring to fig. 1, a flowchart of a brightness adjustment method according to an embodiment of the present invention is shown, and is applied to a backlight module, and specifically includes the following steps:
In the embodiment of the present invention, in order to avoid the phenomenon that the liquid crystal is always kept in a deflection state, so that the display image has an afterimage, the deflection state of the liquid crystal needs to be changed, when the deflection state of the liquid crystal is changed, voltages with different positive and negative polarities need to be applied between adjacent frames, and in the process of switching the voltages of the adjacent frames, the liquid crystal is inverted, so that the display brightness value of the display panel in the process is reduced.
In order to adjust the display brightness values of the display panel within a frame time to be consistent, it is necessary to first obtain the brightness change curve of the display panel with the flicker phenomenon, as shown in fig. 2, first adjust the display panel to a specific display picture, such as a gray-scale picture, then align the camera 21 with the display panel 22, and collect the brightness change curve of the display panel 22 within a frame time under the specific gray-scale picture. As shown in fig. 3, which is a luminance variation curve of the display panel at different time points within one frame time, it can be seen from fig. 3 that, within one frame time, there is a difference in luminance at different time points in the luminance variation curve, and there are a lowest display luminance value 31 and a highest display luminance value 32 in fig. 3.
After the brightness change curve is obtained, the brightness change curve is converted into a digital signal, and the process can be completed by deriving the brightness change curve from an oscilloscope. Fig. 4 is a display luminance value after the luminance change curve is converted into a digital signal, a minimum display luminance value 41 and a maximum display luminance value 42 exist in fig. 4, the minimum display luminance value 41 in the display luminance value in fig. 4 corresponds to the lowest display luminance value 31 in the luminance change curve in fig. 3, the maximum display luminance value 42 corresponds to the highest display luminance value 32 in the luminance change curve in fig. 3, the minimum display luminance value is a display luminance value of the lowest point in the luminance change curve obtained when the flicker phenomenon occurs in the display panel, and the maximum display luminance value is a display luminance value of the highest point in the luminance change curve obtained when the flicker phenomenon occurs in the display panel. In fig. 3 and 4, the abscissa is time in ms, the ordinate is luminance in nit, the digital signal includes display luminance values of the display panel at different times in a frame time, and after the digital signal is acquired, the minimum display luminance value in a frame time and the display luminance value at a target time in a frame time are acquired from the digital signal, where the target time is any time in a frame time. The minimum display brightness value and the display brightness value at the target moment are obtained, so that the duty ratio coefficient corresponding to the subsequent target moment can be conveniently determined.
And step 102, determining a duty ratio coefficient corresponding to the target time according to the minimum display brightness value and the display brightness value of the target time.
In the embodiment of the present invention, after the minimum display luminance value and the display luminance value at the target time are obtained, the duty ratio coefficient corresponding to the target time is determined by using the minimum display luminance value and the display luminance value at the target time.
Since the target time is any time within one frame time, a duty ratio coefficient corresponding to any time within one frame time can be determined by the minimum display brightness value and the display brightness value of the target time, and the determination of the duty ratio coefficient corresponding to the target time can be used for subsequently determining a target duty ratio of a Pulse Width Modulation (PWM) signal of the target time.
In the embodiment of the present invention, the duty ratio at the time corresponding to the minimum display luminance value is set to 1, and the duty ratios at the other times are determined.
And 103, determining the target duty ratio of the pulse width modulation signal at the target moment according to the duty ratio coefficient and the original duty ratio of the pulse width modulation signal.
In the embodiment of the invention, after the duty ratio coefficient corresponding to the target time is determined according to the minimum display brightness value and the display brightness value of the target time, the original duty ratio of the pulse width modulation signal is obtained, and then the target duty ratio of the pulse width modulation signal at the target time is determined according to the duty ratio coefficient corresponding to the target time and the original duty ratio of the pulse width modulation signal. Since the target time is any time within one frame time, the target duty cycle of the pulse width modulation signal at any time within one frame time can be determined by the method, and the acquisition of the target duty cycle can be used for adjusting the pulse width modulation signal.
It should be noted that, in a frame time, the original duty ratios of the pwm signals at any two time instants are the same, but in the embodiment of the present invention, the target duty ratios of the pwm signals at different time instants are different in a frame time.
And 104, sending the target duty ratio to the backlight module so that the backlight module adjusts the pulse width modulation signal corresponding to the target moment according to the target duty ratio.
In the embodiment of the present invention, after the target duty ratio of the pulse width modulation signal at the target time is obtained, a Tcon (Timer Control Register, central Control board) sends the target duty ratio to the backlight module, the backlight module adjusts the pulse width modulation signal at the target time according to the received target duty ratio, and the adjusted pulse width modulation signal can be used to adjust the backlight brightness value of the light actually emitted by the backlight module at the target time.
Correspondingly, the backlight module can adjust the pulse width modulation signal according to the target duty ratio at different moments, and further adjust the backlight brightness value of light rays actually emitted by the backlight module at different moments. Because the target duty ratios of the pwm signals at different times are different within a frame time, the backlight brightness values of the light actually emitted by the backlight module at different times are different.
The display brightness value of the display panel at any moment in a frame time is related to the backlight brightness value of the light actually emitted by the backlight module at the moment. Therefore, the display brightness value of each moment in a frame time can be consistent by adjusting the backlight brightness value of the light rays actually emitted by the backlight module at different time intervals, so that the flicker phenomenon of the display panel is improved.
In the embodiment of the invention, the target duty ratio of the pulse width modulation signal at the target time is determined according to the minimum display brightness value and the display brightness value at the target time of the display panel in one frame time and the original duty ratio of the pulse width modulation signal, and then the pulse width modulation signal at the target time is adjusted according to the target duty ratio, so that the adjusted pulse width modulation signal can change the backlight brightness value of the light which is actually irradiated on the display panel by the backlight module, further the display brightness corresponding to each time of the display panel in one frame time can be kept consistent, the flicker phenomenon of the display panel is eliminated, in addition, the backlight brightness value of the light emitted by the backlight module is adjusted through the duty ratio, the flicker of the display panel is improved, the improvement process is simple, and long test time is not needed.
Example two
Referring to fig. 5, a flowchart of another brightness adjustment method according to an embodiment of the present invention is shown, which may specifically include the following steps:
This step is similar to the principle of step 101 in the first embodiment, and is not described herein again.
In the embodiment of the present invention, the display brightness values of the display panels at any time within one frame time are required to be adjusted to be consistent, that is, the display brightness values of the display panels within one frame time after adjustment are all equal, and when the minimum display brightness value within one frame time is reachedWhen the display brightness value is adjusted, the minimum display brightness value is adjusted to the target display brightness value and is only realized by adjusting the original maximum backlight brightness value of the backlight module, so that the duty ratio of the pulse width modulation signal at this time is still the original duty ratio, that is, the duty ratio coefficient k is 1, and the adjusted display brightness value a of the display panel at this time can be known1Comprises the following steps:
A1＝D0*Lmax*trmin (1)
wherein D is0Is the original duty cycle, tr, of the pulse width modulated signalminThe transmittance of the display panel at the moment corresponding to the minimum display brightness value in a frame time, i.e. the minimum display brightness value l of the display panel in a frame timeminThe ratio of the actual original backlight brightness value of the backlight module to the actual original backlight brightness value D of the backlight module0*L0When the display panel has a flicker picture, the original maximum backlight brightness value L of the corresponding backlight module0Passing through the original duty cycle D0And adjusting the actual backlight brightness value of the backlight module. L ismaxThe target maximum backlight brightness value of the backlight module is the display brightness value at the moment corresponding to the minimum display brightness value in a frame time is adjusted to the target display brightness value ltAnd when the backlight module is in the normal state, the required maximum backlight brightness value of the backlight module is obtained.
When the display brightness of the target time within one frame time is adjusted, the display brightness value A of the display panel of the target time is obtainednComprises the following steps:
An＝D0*k*Lmax*trn (3)
wherein,D0k is the target duty ratio of the PWM signal corresponding to the target time, trnTransmittance of the display panel at the target time within one frame time, i.e. display brightness value l of the display panel at the target time within one frame timenThe ratio of the actual original backlight brightness value of the backlight module is equal to the display brightness value of the display panel at any moment in the next frame time after adjustment, namely A1＝AnThus, it can be known that:
D0*Lmax*trmin＝D0*k*Lmax*trn (5)
from equations (2), (4) and (5), the duty factor k can be derived.
As can be seen from the above formula (6), after the minimum display brightness value and the display brightness value at the target time are determined, the ratio between the minimum display brightness value and the display brightness value at the target time is obtained, that is, the duty ratio coefficient corresponding to the target time can be obtained, and the determination of the target duty ratio coefficient can be used to subsequently adjust the original duty ratio of the pulse width modulation signal.
In the embodiment of the invention, the duty ratio coefficient k and the original duty ratio D of the pulse width modulation signal are obtained0Then, calculating the duty ratio coefficient k and the original duty ratio D0The product is the target duty ratio D of the PWM signal at the target time, D ═ D0*k。
As shown in fig. 6, which is a waveform diagram corresponding to the duty ratio of the pwm signal being the original duty ratio, it can be seen from fig. 6 that the original duty ratios of the pwm signal corresponding to different times within a frame time are all the same; fig. 7 is a waveform schematic diagram corresponding to the case where the duty ratio of the pwm signal is the target duty ratio, where the abscissa in fig. 6 is time, the ordinate is the pwm signal corresponding to the original duty ratio, and the abscissa in fig. 7 is time and the ordinate is the pwm signal corresponding to the target duty ratio.
In conjunction with fig. 4, it can be seen from fig. 7 that the target duty ratio at the time corresponding to the minimum display luminance value within one frame time is unchanged from the original duty ratio in fig. 6, for example, the duty ratio at the time of the pulse width modulation signal T1 in fig. 7 is equal to the duty ratio at the time of the pulse width modulation signal T1 in fig. 6; the target duty ratios on both sides of the time corresponding to the minimum display luminance value are gradually decreased, that is, the target duty ratios corresponding to the times other than the time corresponding to the minimum display luminance value within one frame time are smaller than the target duty ratio of the time corresponding to the minimum display luminance value, for example, the duty ratio of the time T2 of fig. 7 is smaller than the duty ratio of the time T2 of fig. 6, that is, the duty ratio of the time T1 of fig. 7, and the corresponding target duty ratios are also equal when the display luminance values are equal.
The widths 61 and 71 in fig. 6 and 7 represent the magnitude of the duty cycle by which
The display brightness value l at the target time can also be obtainednEqual to the minimum display brightness value lminWhen D is equal to D0When the original duty ratio is equal to the target duty ratio, the display brightness value l at the target momentnGreater than a minimum display brightness value lminWhen D is less than D0The target duty cycle D may be used to adjust the pwm signal at a subsequent target time.
In the embodiment of the present invention, after the target duty ratio is obtained, the target duty ratio is sent to the backlight module, the backlight module may adjust the pulse width modulation signal corresponding to the target time according to the target duty ratio, since the target time is any time within one frame time, the pulse width modulation signal at any time within one frame time may be adjusted, after the adjusted pulse signal acts on the backlight module, the backlight brightness value of the light actually irradiated to the display panel by the backlight module at any time within one frame time may be adjusted, so that after the adjusted brightness value passes through the display panel, the display brightness of the display panel at any time within one frame time may reach the target display brightness, and further, the display brightness of the display panel may be improved.
When a plurality of frames of display images exist, the method can be adopted for adjusting each frame of display image so as to eliminate the flicker phenomenon of each frame of display image. As shown in fig. 8, fig. 9 is a luminance change curve obtained by adjusting the multi-frame display screen in fig. 8, and it can be seen from fig. 9 that the luminances at different times in each frame of the adjusted display screen are substantially the same, so that the flicker phenomenon of the display screen is improved, and the graphs of the voltage versus time in fig. 8 and 9 are synchronization signals obtained when the luminance change curve of the display panel is acquired, and the time to be adjusted can be determined according to the synchronization signals when the pulse width modulation signal is adjusted by duty ratio.
In the embodiment of the present invention, in order to improve the flicker phenomenon of the display panel, the display brightness values of the display panel within one frame time need to be adjusted to be consistent, at this time, the target display brightness value that the display panel needs to reach at each time within one frame time can be determined, when the minimum display brightness value within one frame time is adjusted to be the target display brightness value, the display brightness value at the time other than the time corresponding to the minimum display brightness value within one frame time is adjusted to be the target display brightness value by changing the original duty ratio of the pulse width modulation signal at the corresponding time of the minimum display brightness value and only changing the original maximum backlight brightness value of the backlight module while keeping the original duty ratio of the pulse width modulation signal at the corresponding time of the minimum display brightness value unchanged. The target display brightness value is a reference value for adjusting the display brightness value of the display panel at any moment in the current frame time.
In the embodiment of the invention, the original maximum backlight brightness value of the backlight module is obtained, and then the target maximum backlight brightness value of the backlight module is determined according to the determined target display brightness value, the original maximum backlight brightness value and the minimum display brightness value of the backlight module.
Specifically, step 506 includes sub-steps 5061 and 5062:
substep 5061, calculating the product of the target display brightness value and the original maximum backlight brightness value of the backlight module;
sub-step 5062, determining the ratio of the product to the minimum display brightness value as the target maximum backlight brightness value of the backlight module.
In the embodiment of the invention, the target brightness display value l of the display panel is obtainedtThat is, the display brightness value that the display panel needs to reach at any moment in a frame time is displayed according to the target display brightness value ltTransmittance tr of the display panel at a time corresponding to the minimum display luminance value of the display panel within one frame timeminThe ratio of (a) to (b) can determine the time corresponding to the minimum display brightness value, and the display brightness value is adjusted to the target display brightness value ltActual target backlight brightness value D required by time-required backlight module0*LmaxI.e. by
The actual target backlight brightness value D of the backlight module0*LmaxFor improving the target maximum backlight brightness value L of the corresponding backlight module when the display panel has a flicker picturemaxThe actual backlight brightness value of the backlight module after the target duty ratio adjustment is D because the duty ratio k at this time is 1, and the actual target backlight brightness value of the backlight module at this time is D0*LmaxDue to D0Is known so that a target maximum backlight brightness value L of the backlight module can be determinedmax，LmaxThe specific calculation formula of (2) is as follows:
therefore, the target maximum backlight brightness value L of the backlight module is determinedmaxIn the first step, the target display brightness value l is determinedtAnd the original maximum backlight brightness value L of the backlight module0The product of (a).
In the embodiment of the invention, the target maximum backlight brightness value L of the backlight module is calculatedmaxThen, according to the above formula (9), the target display brightness value l is obtainedtAnd the original maximum backlight brightness value L of the backlight module0And after the product is obtained, calculating the ratio of the product to the minimum display brightness value, and finally determining the ratio as the target maximum backlight brightness value of the backlight module, wherein the determination of the target maximum backlight brightness value can be used for adjusting the original maximum backlight brightness value of the backlight module, so that the display brightness value of the display panel is adjusted.
In the embodiment of the invention, when the determined target display brightness value of the display panel is ltThen, for the time corresponding to the minimum display brightness value in one frame time of the acquired display panel with the flicker phenomenon, the display brightness value A of the display panel at the adjusted time is1Comprises the following steps:
A1＝D0*Lmax*trmin＝lt (10)
when the determined target display brightness value of the display panel is ltThen, for the time of the maximum display brightness value in one frame time of the display panel with the flicker phenomenon, the adjusted display brightness value A of the display panel2Comprises the following steps:
A2＝D*Lmax*trmax＝lt (11)
therefore, the display brightness value at any time in one frame time after being adjusted by the method is equal and can reach the target display brightness value, so that the flicker phenomenon of the display panel can be improved.
It should be noted that when the target display luminance value lt＝lminThen, the display brightness values of the display panel at different moments in a frame time are all adjusted to the minimum display brightness value lminThen, according to the formula (9), Lmax＝L0That is, the original maximum backlight brightness value of the backlight module does not need to be adjusted.
When l ist＝lmaxThen, the display brightness values of the display panel at different moments in a frame time are all adjusted to the maximum display brightness value lmaxThen, according to the formula (9),
wherein the maximum display brightness value lmaxThe maximum display brightness value of the display panel with flicker phenomenon in one frame time can be known from formula (12), at this time, LmaxIs not equal to L0Therefore, the original maximum luminance backlight value of the backlight module needs to be adjusted.
In the embodiment of the invention, after the target maximum backlight brightness value of the backlight module is determined, the target maximum backlight brightness value is sent to the backlight module, and the target maximum backlight brightness value of the backlight module is determined when the display brightness value at the moment corresponding to the minimum display brightness value is adjusted to the target display brightness value, so that when the backlight module adopts the target maximum backlight brightness value, the minimum display brightness value of the display panel in one frame time can be adjusted to the target display brightness value, and the adjustment of the minimum display brightness value is achieved.
After the original maximum backlight brightness value of the backlight module is adjusted to the target maximum backlight brightness value, the duty ratios of the display panel at any time in a frame time are all the target display brightness value by adjusting the duty ratios of the display panel at other times except the time corresponding to the minimum display brightness value.
In the embodiment of the invention, firstly, the target duty ratio of the pulse width modulation signal at the target time is determined according to the minimum display brightness value of the display panel in one frame time, the display brightness value at the target time and the original duty ratio of the pulse width modulation signal, then the pulse width modulation signal at the target time is adjusted according to the target duty ratio, and the adjusted pulse width modulation signal can change the backlight brightness value of light actually irradiated on the display panel, so that the display brightness of the display panel corresponding to each time in one frame time is kept consistent, and the flicker phenomenon of the display panel is eliminated; secondly, the backlight brightness value of the light emitted by the backlight module is adjusted through the duty ratio so as to improve the flicker of the display panel, the improvement process is simple, and long test time is not needed; and determining a target display brightness value which needs to be reached by the display panel within a frame time, determining a target maximum backlight brightness value of the backlight module according to the target display brightness value, an original maximum backlight brightness value of the backlight module and a minimum display brightness value of the display panel, and further enabling the backlight module to emit light according to the target maximum backlight brightness value, so that the original maximum backlight brightness value of the backlight module can be adjusted to improve the display brightness of the display panel.
EXAMPLE III
Fig. 10 is a block diagram illustrating a structure of a luminance adjusting apparatus according to an embodiment of the present invention.
The brightness adjusting device 1000 is applied to a backlight module, and includes:
a display luminance value obtaining module 1001 configured to obtain a minimum display luminance value of a display panel within one frame time and a display luminance value of a target time within the one frame time; the target time is any time in the frame time;
a duty ratio determining module 1002, configured to determine a duty ratio corresponding to the target time according to the minimum display brightness value and the display brightness value at the target time;
a target duty cycle determination module 1003 configured to determine a target duty cycle of the pwm signal at the target time according to the duty cycle coefficient and an original duty cycle of the pwm signal;
a target duty ratio sending module 1004 configured to send the target duty ratio to the backlight module, so that the backlight module adjusts the pulse width modulation signal corresponding to the target time according to the target duty ratio.
Optionally, the duty ratio coefficient determining module 1002 includes:
a duty ratio determining submodule configured to determine a ratio of the minimum display brightness value to the display brightness value at the target time as a duty ratio corresponding to the target time.
Optionally, the target duty ratio determining module 1003 includes:
a target duty cycle determination submodule configured to determine a product of the duty cycle coefficient and an original duty cycle of a pulse width modulation signal as a target duty cycle of the pulse width modulation signal at the target time.
Optionally, the brightness adjusting apparatus 1000 further includes:
a target display brightness value determining module configured to determine a target display brightness value that the display panel needs to reach at each moment within the one frame time;
a target maximum backlight brightness value determining module configured to determine a target maximum backlight brightness value of the backlight module according to the target display brightness value, an original maximum backlight brightness value of the backlight module, and the minimum display brightness value;
and the target maximum backlight brightness value sending module is configured to send the target maximum backlight brightness value to the backlight module so that the backlight module emits light according to the target maximum backlight brightness value.
Optionally, the target maximum backlight brightness value determining module includes:
a product calculation sub-module configured to calculate a product of the target display brightness value and an original maximum backlight brightness value of the backlight module;
and the target maximum backlight brightness value determining submodule is configured to determine the ratio of the product to the minimum display brightness value as the target maximum backlight brightness value of the backlight module.
In the embodiment of the invention, the target duty ratio of the pulse width modulation signal at the target time is determined according to the minimum display brightness value and the display brightness value at the target time of the display panel in one frame time and the original duty ratio of the pulse width modulation signal, and then the pulse width modulation signal at the target time is adjusted according to the target duty ratio, so that the adjusted pulse width modulation signal can change the backlight brightness value of the light which is actually irradiated on the display panel by the backlight module, further the display brightness corresponding to each time of the display panel in one frame time can be kept consistent, the flicker phenomenon of the display panel is eliminated, in addition, the backlight brightness value of the light emitted by the backlight module is adjusted through the duty ratio, the flicker of the display panel is improved, the improvement process is simple, and long test time is not needed.
Example four
The embodiment of the invention also provides a display device which comprises the brightness adjusting device.
The display device also comprises a backlight module and a display panel, wherein the display panel is arranged on the light emergent side of the backlight module; the backlight module comprises a backlight driving chip and a backlight substrate, wherein the backlight driving chip is configured to adjust the pulse width modulation signal corresponding to the target time according to the target duty ratio and control the backlight brightness value of light rays actually emitted by the backlight substrate according to the adjusted pulse width modulation signal.
In the embodiment of the invention, the brightness adjusting device is Tcon, the Tcon sends the target duty ratio to a backlight driving chip in the backlight module, the backlight driving chip adjusts the pulse width modulation signal according to the received target duty ratio, the backlight driving chip sends the adjusted pulse width modulation signal to the backlight substrate, the backlight substrate emits light according to the adjusted pulse width modulation signal, and then the backlight brightness value of the light which is actually irradiated on the display panel by the backlight module and is required by the target time is obtained, and the backlight brightness value can enable the display brightness value at any time within one frame time to be consistent, so that the flicker phenomenon of the display panel is improved.
Further, when the target maximum backlight brightness value of the backlight module is not equal to the original maximum backlight brightness value of the backlight module, the target maximum backlight brightness value of the backlight module needs to be sent to a backlight driving chip in the backlight module, and the backlight driving chip increases a driving voltage for driving the backlight substrate, so that the driving current of the backlight substrate is increased, the original maximum backlight brightness value of the backlight module is changed, and the display brightness of the display panel is adjusted.
And the backlight module can be a direct type backlight module or a side type backlight module, preferably the direct type backlight module is adopted, and the refreshing mode of the display panel is refreshing line by line, and the position of the refreshing line of the direct type backlight module is basically consistent with the position of the refreshing line of the display panel, so that the optimal improvement effect on the display brightness of the display panel can be achieved.
In the embodiment of the present invention, the display device may be: the mobile phone, the tablet personal computer, the television, the notebook computer, the vehicle-mounted display product and other products or components with flickering pictures.
In the embodiment of the invention, the target duty ratio of the pulse width modulation signal at the target time is determined according to the minimum display brightness value and the display brightness value at the target time of the display panel in one frame time and the original duty ratio of the pulse width modulation signal, and then the pulse width modulation signal at the target time is adjusted according to the target duty ratio, so that the adjusted pulse width modulation signal can change the backlight brightness value of the light which is actually irradiated on the display panel by the backlight module, further the display brightness corresponding to each time of the display panel in one frame time can be kept consistent, the flicker phenomenon of the display panel is eliminated, in addition, the backlight brightness value of the light emitted by the backlight module is adjusted through the duty ratio, the flicker of the display panel is improved, the improvement process is simple, and long test time is not needed.
While, for purposes of simplicity of explanation, the foregoing method embodiments have been described as a series of acts or combination of acts, it will be appreciated by those skilled in the art that the present invention is not limited by the illustrated ordering of acts, as some steps may occur in other orders or concurrently with other steps in accordance with the invention. Further, those skilled in the art should also appreciate that the embodiments described in the specification are preferred embodiments and that the acts and modules referred to are not necessarily required by the invention.
The embodiments in the present specification are described in a progressive manner, each embodiment focuses on differences from other embodiments, and the same and similar parts among the embodiments are referred to each other.
Finally, it should also be noted that, herein, relational terms such as first and second, and the like may be used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Also, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. The use of the phrase "including a" does not exclude the presence of other, identical elements in the process, method, article, or apparatus that comprises the same element, whether or not the same element is present in all of the same element.
The brightness adjusting method, the brightness adjusting device and the display device provided by the present invention are described in detail above, and the principle and the implementation of the present invention are explained in this document by applying specific examples, and the description of the above examples is only used to help understanding the method and the core idea of the present invention; meanwhile, for a person skilled in the art, according to the idea of the present invention, there may be variations in the specific embodiments and the application scope, and in summary, the content of the present specification should not be construed as a limitation to the present invention.
Claims (8)
1. A brightness adjusting method is applied to a backlight module, and the method comprises the following steps:
acquiring a minimum display brightness value of a display panel in a frame time and a display brightness value of a target moment in the frame time; the target time is any time in the frame time;
determining a duty ratio coefficient corresponding to the target moment according to the minimum display brightness value and the display brightness value of the target moment;
determining a target duty ratio of the pulse width modulation signal at the target moment according to the duty ratio coefficient and an original duty ratio of the pulse width modulation signal;
sending the target duty ratio to the backlight module so that the backlight module adjusts the pulse width modulation signal corresponding to the target moment according to the target duty ratio;
the step of determining the duty ratio coefficient corresponding to the target time according to the minimum display brightness value and the display brightness value at the target time includes:
and determining the ratio of the minimum display brightness value to the display brightness value at the target moment as a duty ratio coefficient corresponding to the target moment.
2. The method of claim 1, wherein the step of determining the target duty cycle of the pwm signal at the target time based on the duty cycle factor and an original duty cycle of the pwm signal comprises:
and determining the product of the duty ratio coefficient and the original duty ratio of the pulse width modulation signal as the target duty ratio of the pulse width modulation signal at the target moment.
3. The method according to claim 1, further comprising, after the step of obtaining a minimum display brightness value of the display panel in one frame time and a display brightness value of the display panel at a target time in the one frame time:
determining a target display brightness value which needs to be reached by the display panel at each moment in the frame time;
determining a target maximum backlight brightness value of the backlight module according to the target display brightness value, the original maximum backlight brightness value of the backlight module and the minimum display brightness value;
and sending the target maximum backlight brightness value to the backlight module so that the backlight module emits light according to the target maximum backlight brightness value.
4. The method of claim 3, wherein the step of determining the target maximum backlight brightness value of the backlight module according to the target display brightness value, the original maximum backlight brightness value of the backlight module and the minimum display brightness value comprises:
calculating the product of the target display brightness value and the original maximum backlight brightness value of the backlight module;
and determining the ratio of the product to the minimum display brightness value as a target maximum backlight brightness value of the backlight module.
5. A brightness adjusting device is applied to a backlight module, and the device comprises:
the display brightness value acquisition module is configured to acquire a minimum display brightness value of a display panel in one frame time and a display brightness value of a target moment in the one frame time; the target time is any time in the frame time;
a duty ratio coefficient determining module configured to determine a duty ratio coefficient corresponding to the target time according to the minimum display brightness value and the display brightness value of the target time;
a target duty cycle determination module configured to determine a target duty cycle of the pulse width modulation signal at the target time according to the duty cycle coefficient and an original duty cycle of the pulse width modulation signal;
a target duty ratio sending module configured to send the target duty ratio to the backlight module, so that the backlight module adjusts the pulse width modulation signal corresponding to the target time according to the target duty ratio; the duty cycle coefficient determining module comprises:
a duty ratio determining submodule configured to determine a ratio of the minimum display brightness value to the display brightness value at the target time as a duty ratio corresponding to the target time.
6. The apparatus of claim 5, wherein the target duty cycle determination module comprises:
a target duty cycle determination submodule configured to determine a product of the duty cycle coefficient and an original duty cycle of a pulse width modulation signal as a target duty cycle of the pulse width modulation signal at the target time.
7. A display device comprising the luminance adjusting device according to any one of claims 5 to 6.
8. The display device according to claim 7, further comprising a backlight module and a display panel, wherein the display panel is disposed on a light emitting side of the backlight module;
the backlight module comprises a backlight driving chip and a backlight substrate, wherein the backlight driving chip is configured to adjust the pulse width modulation signal corresponding to the target time according to the target duty ratio and control the backlight brightness value of light rays actually emitted by the backlight substrate according to the adjusted pulse width modulation signal.
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Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102177540A (en) * | 2008-10-10 | 2011-09-07 | 夏普株式会社 | Image display device |
| CN103018934A (en) * | 2012-12-07 | 2013-04-03 | 京东方科技集团股份有限公司 | Liquid crystal module testing device |
| CN104299602A (en) * | 2014-08-28 | 2015-01-21 | 京东方科技集团股份有限公司 | Backlight compensation method, backlight source and display device |
| KR20160084035A (en) * | 2015-01-05 | 2016-07-13 | 엘지디스플레이 주식회사 | Liquid Crystal Display and Driving Method of the Same |
| JP2017203973A (en) * | 2016-05-09 | 2017-11-16 | 中華映管股▲ふん▼有限公司 | Liquid crystal display device and driving method of the same |
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Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102177540A (en) * | 2008-10-10 | 2011-09-07 | 夏普株式会社 | Image display device |
| CN103018934A (en) * | 2012-12-07 | 2013-04-03 | 京东方科技集团股份有限公司 | Liquid crystal module testing device |
| CN104299602A (en) * | 2014-08-28 | 2015-01-21 | 京东方科技集团股份有限公司 | Backlight compensation method, backlight source and display device |
| KR20160084035A (en) * | 2015-01-05 | 2016-07-13 | 엘지디스플레이 주식회사 | Liquid Crystal Display and Driving Method of the Same |
| JP2017203973A (en) * | 2016-05-09 | 2017-11-16 | 中華映管股▲ふん▼有限公司 | Liquid crystal display device and driving method of the same |
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