Backlight driving method and liquid crystal display device

Abstract

The present application discloses a backlight driving method and a liquid crystal display device. The backlight driving method first determines the total luminous flux value of each display partition based on video data and a light intensity coefficient table, then determines the total luminous flux value of each backlight partition according to the total luminous flux value of each display partition, then calculates the light intensity of each lamp bead based on the total luminous flux value of the backlight partition, and then determines the driving parameters of each lamp bead according to the light intensity of each lamp bead, thereby meeting the luminous flux requirements of a moving object at different positions, reducing or avoiding the brightness difference between the moving object at different positions, and thereby improving or avoiding the flickering phenomenon of the moving object.

Description

Technical Field

[0001] The present application relates to the field of display technology, and in particular to a backlight driving method and a liquid crystal display device. Background Art

[0002] In display technology, as an object moves, it will show different brightness changes, i.e. flicker, such as Figure 1 As described above, the small balls will present corresponding different brightness in different areas or different positions in the same area, which makes the human eye perceive corresponding flickering phenomenon, affecting the display quality. Summary of the invention

[0003] The present application provides a backlight driving method and a liquid crystal display device to alleviate the technical problem of brightness changes occurring during the movement of an object.

[0004] In a first aspect, the present application provides a backlight driving method, which includes: determining the total luminous flux value of each display partition based on video data and a light intensity coefficient table; determining the total luminous flux value of each backlight partition according to the total luminous flux value of each display partition; calculating the light intensity of each lamp bead based on the total luminous flux value of the backlight partition; and determining the driving parameters of each lamp bead according to the light intensity of each lamp bead.

[0005] In some of the embodiments, the step of determining the total luminous flux of each display partition based on video data and a light intensity coefficient table includes: determining the light intensity coefficient corresponding to each pixel according to the proportion of the total luminous flux of each backlight partition at the corresponding pixel position; and combining the light intensity coefficients of each pixel into a light intensity coefficient table.

[0006] In some of the embodiments, the step of determining the total luminous flux of each display partition based on the video data and the light intensity coefficient table also includes: obtaining the brightness data of each pixel according to the video data; and determining the product of the brightness data of each pixel and the corresponding light intensity coefficient as the luminous flux of the image at the corresponding position.

[0007] In some implementations, the step of determining the total luminous flux value of each display partition based on the video data and the light intensity coefficient table further includes: determining the sum of the luminous fluxes of images at each position in the same display partition as the total luminous flux value of the display partition.

[0008] In some of the embodiments, the step of determining the total luminous flux value of each backlight partition based on the total luminous flux value of each display partition includes: configuring a display partition to correspond to a backlight partition in the light emitting direction; determining the total luminous flux value of a display partition to be the total luminous flux value of the corresponding backlight partition.

[0009] In some of the embodiments, the step of calculating the light intensity of each lamp bead based on the total luminous flux of the backlight partition includes: obtaining the luminous flux components that influence each other between adjacent backlight partitions; and determining the difference between the total luminous flux of a backlight partition and the luminous flux components of the adjacent backlight partitions as the luminous flux of the backlight partition.

[0010] In some of the embodiments, the step of calculating the light intensity of each lamp bead based on the total luminous flux of the backlight partition also includes: determining the solid angle of each lamp bead in the same backlight partition; determining the light intensity of each lamp bead in the backlight partition based on the luminous flux of the backlight partition and the solid angle of each lamp bead in the backlight partition, the light intensity of the lamp bead being the luminous flux emitted within a unit solid angle in a specified direction.

[0011] In some embodiments, the step of determining the driving parameters of each lamp bead according to the light intensity of each lamp bead includes: configuring the driving parameters to include the light-emitting time and the light-emitting current; determining the light-emitting time and / or the light-emitting current of each lamp bead according to the light intensity of each lamp bead.

[0012] In some of the embodiments, the backlight driving method further includes: constructing a same backlight partition to have one or more lamp beads; configuring each lamp bead in the same backlight partition to have the same driving parameters.

[0013] In a second aspect, the present application provides a liquid crystal display device, which executes the backlight driving method in at least one of the above-mentioned embodiments.

[0014] The backlight driving method and liquid crystal display device provided in the present application first determine the total luminous flux value of each display partition based on video data and a light intensity coefficient table, then determine the total luminous flux value of each backlight partition based on the total luminous flux value of each display partition, and then calculate the light intensity of each lamp bead based on the total luminous flux value of the backlight partition, and then determine the driving parameters of each lamp bead based on the light intensity of each lamp bead, thereby meeting the luminous flux requirements of a moving object at different positions, reducing or avoiding the brightness difference between moving objects at different positions, and thereby improving or avoiding the flickering phenomenon of a moving object. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] The technical solution and other beneficial effects of the present application will be made apparent by describing in detail the specific implementation methods of the present application in conjunction with the accompanying drawings.

[0016] Figure 1 A schematic diagram of the motion trajectory of an object in related display technology.

[0017] Figure 2 A schematic diagram of a flow chart of a backlight driving method provided in an embodiment of the present application.

[0018] Figure 3Another schematic flow chart of a backlight driving method provided in an embodiment of the present application.

[0019] Figure 4 A schematic diagram of the structure of the lamp beads in the backlight partition provided in the embodiment of the present application.

[0020] Figure 5 A schematic diagram of light distribution of a light source provided in an embodiment of the present application.

[0021] Figure 6 A schematic diagram of the light distribution of the lamp beads provided in an embodiment of the present application.

[0022] Figure 7 A schematic diagram of how the different numbers of lamp beads turned on affect the display partitions provided in the embodiment of the present application.

[0023] Figure 8 A schematic diagram of the luminous flux received by each pixel provided in an embodiment of the present application.

[0024] Fig. 9 A schematic diagram of the distribution of backlight subareas in the backlight area provided in an embodiment of the present application.

[0025] Fig.10 A schematic diagram of the correspondence between the backlight partitions and the display partitions provided in an embodiment of the present application. DETAILED DESCRIPTION

[0026] The technical solutions in the embodiments of the present application will be described clearly and completely below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the present application.

[0027] In addition, the terms "first" and "second" are used for descriptive purposes only and cannot be understood as indicating or suggesting relative importance or implicitly indicating the number of technical features indicated. Therefore, the features specified as "first" and "second" may explicitly or implicitly include one or more of the said features. In the description of the present invention, "multiple" means two or more, unless otherwise clearly and specifically defined.

[0028] In view of the technical problem of brightness change of the object during the movement mentioned above, this embodiment provides a backlight driving method, please refer to Figures 1 to 10 ,like Figure 2 As shown, the backlight driving method includes the following steps:

[0029] Step S10: Determine the total luminous flux value of each display partition based on the video data and the light intensity coefficient table.

[0030] Step S20: determining the total luminous flux value of each backlight subarea according to the total luminous flux value of each display subarea.

[0031] Step S30: Calculate the light intensity of each lamp bead based on the total value of the luminous flux of the backlight partition.

[0032] Step S40: Determine the driving parameters of each lamp bead according to the light intensity of each lamp bead.

[0033] It can be understood that the backlight driving method provided in the present embodiment first determines the total luminous flux value of each display partition based on the video data and the light intensity coefficient table, then determines the total luminous flux value of each backlight partition according to the total luminous flux value of each display partition, and then calculates the light intensity of each lamp bead based on the total luminous flux value of the backlight partition, and then determines the driving parameters of each lamp bead according to the light intensity of each lamp bead, thereby meeting the luminous flux requirements of the moving object at different positions, reducing or avoiding the brightness difference between the moving object at different positions, and thereby improving or avoiding the flickering phenomenon of the moving object.

[0034] It should be noted that one or more pixels are provided in each display partition, and the display partitions are combined to form an effective display area of ​​the liquid crystal display panel. One or more lamp beads are provided in each backlight partition, and the backlight partitions are combined to form the backlight area of ​​the backlight module. Among them, each lamp bead can be a mini light-emitting diode (Mini-LED) or a micro light-emitting diode (Micro-LED). The liquid crystal display panel and the backlight module can present the corresponding picture according to the video data accessed from the outside.

[0035] In one of the embodiments, the step of determining the total luminous flux of each display partition based on video data and a light intensity coefficient table includes: determining the light intensity coefficient corresponding to each pixel according to the proportion of the total luminous flux of each backlight partition at the corresponding pixel position; and combining the light intensity coefficients of each pixel into a light intensity coefficient table.

[0036] It should be noted that each light intensity coefficient can be obtained through optical measurement after the product is completed. The finished product can be, for example, a product after the combination of a liquid crystal display panel and a backlight module is finalized. In this case, the spacing, quantity and other configurations of each lamp bead have been finalized.

[0037] In one of the embodiments, the step of determining the total luminous flux of each display partition based on the video data and the light intensity coefficient table also includes: obtaining the brightness data of each pixel according to the video data; and determining the product of the brightness data of each pixel and the corresponding light intensity coefficient as the luminous flux of the image at the corresponding position.

[0038] It should be noted that the brightness data of each pixel can be extracted from the video data.

[0039] In one of the embodiments, the step of determining the total luminous flux value of each display partition based on the video data and the light intensity coefficient table further includes: determining the sum of the luminous fluxes of the images at each position in the same display partition as the total luminous flux value of the display partition.

[0040] It should be noted that this embodiment provides a specific method for calculating the total luminous flux value of each display partition, and the total luminous flux value of each display partition can be calculated in turn.

[0041] In one of the embodiments, the step of determining the total luminous flux value of each backlight partition according to the total luminous flux value of each display partition includes: configuring a display partition to correspond to a backlight partition in the light emitting direction; determining the total luminous flux value of a display partition to be the total luminous flux value of the corresponding backlight partition.

[0042] It should be noted that, in the light emitting direction, the backlight subarea at least partially overlaps with the display subarea corresponding to the backlight subarea.

[0043] In one of the embodiments, the step of calculating the light intensity of each lamp bead based on the total luminous flux of the backlight partition includes: obtaining the luminous flux components that affect each other between adjacent backlight partitions; determining the difference between the total luminous flux of a backlight partition and the luminous flux component of the adjacent backlight partition as the luminous flux of the backlight partition.

[0044] It should be noted that the total luminous flux value of each backlight partition is not only related to its own luminous flux, but also to the luminous flux component affected by the adjacent backlight partition.

[0045] In one of the embodiments, the step of calculating the light intensity of each lamp bead based on the total luminous flux of the backlight partition also includes: determining the solid angle of each lamp bead in the same backlight partition; determining the light intensity of each lamp bead in the backlight partition based on the luminous flux of the backlight partition and the solid angle of each lamp bead in the backlight partition, the light intensity of the lamp bead being the luminous flux emitted within a unit solid angle in a specified direction.

[0046] It should be noted that for any position on the plane where the pixel is located, the solid angle of the corresponding lamp bead can be obtained through optical measurement and can also be determined.

[0047] In one embodiment, the step of determining the driving parameters of each lamp bead according to the light intensity of each lamp bead includes: configuring the driving parameters to include the light-emitting time and the light-emitting current; determining the light-emitting time and / or the light-emitting current of each lamp bead according to the light intensity of each lamp bead.

[0048] It should be noted that the driving parameters are strongly correlated with the light intensity of the corresponding lamp beads, and the light intensity of each lamp bead can be adjusted by at least one of the light-emitting time and the light-emitting current.

[0049] In one of the embodiments, the backlight driving method further includes: constructing a same backlight partition with one or more lamp beads; configuring each lamp bead in the same backlight partition to have the same driving parameters.

[0050] It should be noted that the data of the lamp beads in each backlight partition can be the same or different, and there is no specific limitation. The driving parameters of the lamp beads in the same backlight partition can be the same, which can simplify the design of the driving circuit of each lamp bead compared to the different driving parameters of the lamp beads in the same backlight partition.

[0051] In summary, the working principle of the above backlight driving method is as follows: Figure 3 As shown:

[0052] After power-on, the system coefficient table, i.e., the light intensity coefficient table [λ(i, j)], is loaded, where λ(i, j) is the light intensity coefficient of the position with coordinates (i, j). Then, the brightness value of the image at any position in the display partition, i.e., the luminous flux Φ(i, j), is calculated based on the video data and the light intensity coefficient table:

[0053] Φ(i,j)=λ(i,j)*Pixel(i,j)

[0054] Among them, Pixel (i, j) is the brightness data of the corresponding pixel.

[0055] Then the image brightness Φ(m, n) of the display partition is analyzed and counted as follows:

[0056] Φ(m,n)=ΣΦ(i,j)

[0057] Then, the total image brightness value of the display partition, that is, the total luminous flux value Φ(total)=Φ(m,n) is determined.

[0058] Then determine the total value of the luminous flux of a backlight partition Φ(total)=Φ(N)+Φ'(N), where Φ(N) is the luminous flux of backlight partition N, and Φ'(N) is the luminous flux component of the backlight partition N affected by the adjacent backlight partition.

[0059] Then based on the luminous flux of backlight partition N, Φ(N)=I 1 *Ω 1 +I 2 *Ω 2 +I 3 *Ω 3 +I 4 *Ω 4 +...Calculate the light intensity of each lamp bead.

[0060] It should be noted that, taking a backlight partition with four lamp beads as an example, I1 -I 4 The light intensity of lamp beads 1 to 4, Ω 1 -Ω 4 These are the solid angles of the illuminated position of lamp beads 1 to 4, respectively. The same can be applied to the case where a backlight partition has other numbers of lamp beads.

[0061] Then, based on the known light intensity, the control parameters of the backlight adjustment are calculated, that is, the driving parameters of each lamp bead are determined.

[0062] The specific description of the above backlight driving method is as follows:

[0063] like Figure 4 As shown, each backlight partition may be composed of 4 lamp beads, 6 lamp beads, 9 lamp beads, or more lamp beads. The lamp beads in the same backlight partition may be distributed in an array.

[0064] like Figure 5 The light source shown is distributed in a ray gradient, such as Figure 6 The light from the lamp beads shown is also distributed in a ray gradient. Figure 5 , Figure 6 The light gradient distribution shown will have different brightness distribution for backlight partitions with different layouts.

[0065] Take the layout analysis of 4 lamp beads in a backlight partition as an example. Figure 7 As shown, from turning on 1 lamp bead (1LED) to turning on 4 lamp beads (4LED), since the light distribution is a ray-shaped gradient distribution, the brightness is related to the space, that is, the luminous flux φ=I*Ω, where I is the light intensity, that is, the luminous flux emitted by the light source within a unit solid angle in a specified direction; Ω is the solid angle.

[0066] Based on the above luminous flux calculation formula, we can get Figure 8 The luminous flux Φ(n) irradiated at any position n on the screen shown is the comprehensive superposition of all lamp beads in the backlight partition.

[0067] Φ(n)=I 1 *Ω 1 (n)+I 2 *Ω 2 (n)+I 3 *Ω 3 (n)+I 4 *Ω 4 (n)

[0068] Among them, taking a backlight partition with four lamp beads as an example, I 1 -I 4 The light intensity of lamp beads 1 to 4, Ω 1 -Ω4 These are the solid angles of lamp beads 1 to 4 to the illuminated position n. The same can be applied to the case where a backlight partition has other numbers of lamp beads.

[0069] The above is an independent analysis based on each backlight partition. The luminous flux of each pixel position in the display partition is determined by the light intensity distribution of each lamp bead in the corresponding backlight partition. At the same time, since each backlight partition is not independent of each other, the luminous flux of each pixel position should take into account the influence of the light intensity of the adjacent backlight partition.

[0070] That is to say, the luminous flux at each pixel position is mainly determined by the light intensity of each lamp bead in the corresponding backlight partition, and is related to the light intensity of each lamp bead in the adjacent backlight partition.

[0071] Φ(N)=I 1 *Ω 1 (N)+I 2 *Ω 2 (N)+I 3 *Ω 3 (N)+I 4 *Ω 4 (N)+φ'(N)

[0072] Among them, Φ(N) is as follows Fig. 9 Φ'(N) is the total luminous flux of backlight partition N. Φ'(N) is the luminous flux component of adjacent backlight partitions that affects backlight partition N. For example, a backlight partition has four lamp beads. 1 -I 4 They are the light intensity of lamp beads 1 to 4 in backlight partition N, Ω 1 (N)-Ω 4 (N) are respectively the solid angles of lamp beads 1 to 4 in backlight partition N to the illuminated position n.

[0073] The backlight partition N corresponds to Fig.10 The display partition shown is provided with n rows and m columns of pixels, and the brightness data of any pixel in the display partition is recorded as Pixel (i, j).

[0074] Then the brightness value of the image at any position in the display partition is the luminous flux Φ(i, j):

[0075] Φ(i,j)=λ(i,j)*Pixel(i,j)

[0076] Then the image brightness Φ(m, n) of the display partition is analyzed and counted as follows:

[0077] Φ(m,n)=ΣΦ(i,j)

[0078] Then, the total brightness value of the image in the displayed partition, that is, the total luminous flux value Φ(total)=Φ(m,n).

[0079] It is understandable that the total value of the luminous flux of each display partition can be obtained in this way. Based on this, the above backlight driving method can solve the uneven brightness, that is, the flickering phenomenon, which occurs during the movement of an object.

[0080] In one embodiment, the present embodiment provides a liquid crystal display device, which executes the backlight driving method in at least one of the above embodiments.

[0081] It can be understood that since the liquid crystal display device provided in this embodiment executes the backlight driving method in at least one of the above-mentioned embodiments, it can also determine the total luminous flux value of each display partition based on the video data and the light intensity coefficient table, and then determine the total luminous flux value of each backlight partition according to the total luminous flux value of each display partition, and then calculate the light intensity of each lamp bead based on the total luminous flux value of the backlight partition, and then determine the driving parameters of each lamp bead according to the light intensity of each lamp bead, thereby meeting the luminous flux requirements of the moving object at different positions, reducing or avoiding the brightness difference between the moving object at different positions, and thereby improving or avoiding the flickering phenomenon of the moving object.

[0082] In the above embodiments, the description of each embodiment has its own emphasis. For parts that are not described in detail in a certain embodiment, reference can be made to the relevant descriptions of other embodiments.

[0083] The backlight driving method and the liquid crystal display device provided in the embodiments of the present application are introduced in detail above. Specific examples are used in this article to illustrate the principles and implementation methods of the present application. The description of the above embodiments is only used to help understand the technical solutions and core ideas of the present application. Ordinary technicians in this field should understand that they can still modify the technical solutions recorded in the aforementioned embodiments, or replace some of the technical features therein with equivalents; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present application.

Claims

1. A backlight driving method, characterized in that: The backlight driving method comprises: Determine the total luminous flux value of each display partition based on the video data and the light intensity coefficient table; Determine the total luminous flux value of each backlight partition according to the total luminous flux value of each display partition; Calculate the light intensity of each lamp bead based on the total luminous flux of the backlight partition; Determine the driving parameters of each lamp bead according to the light intensity of each lamp bead; The step of determining the total value of the luminous flux of each display partition based on the video data and the light intensity coefficient table includes: Determine the light intensity coefficient corresponding to each pixel according to the effect ratio of the total luminous flux of each backlight partition on the corresponding pixel position; The light intensity coefficients of each pixel are collected to form the light intensity coefficient table.

2. The backlight driving method according to claim 1, characterized in that: The step of determining the total luminous flux value of each display partition based on the video data and the light intensity coefficient table further includes: Obtaining brightness data of each pixel according to the video data; The product of the brightness data of each pixel and the corresponding light intensity coefficient is determined as the luminous flux of the image at the corresponding position.

3. The backlight driving method according to claim 2, characterized in that: The step of determining the total luminous flux value of each display partition based on the video data and the light intensity coefficient table further includes: The sum of the luminous fluxes of the images at each position in the same display partition is determined as the total luminous flux value of the display partition.

4. The backlight driving method according to claim 1, characterized in that: The step of determining the total luminous flux value of each backlight partition according to the total luminous flux value of each display partition comprises: Arrange a display partition and a backlight partition to correspond to each other in the light emitting direction; The total luminous flux value of a display subarea is determined to be the total luminous flux value of the corresponding backlight subarea.

5. The backlight driving method according to claim 1, characterized in that: The step of calculating the light intensity of each lamp bead based on the total value of the luminous flux of the backlight partition includes: Obtaining the luminous flux components that affect each other between adjacent backlight partitions; The difference between the total value of the luminous flux of a backlight partition and the luminous flux component of an adjacent backlight partition is determined as the luminous flux of the backlight partition.

6. The backlight driving method according to claim 5, characterized in that: The step of calculating the light intensity of each lamp bead based on the total value of the luminous flux of the backlight partition also includes: Determine the solid angle of each lamp bead in the same backlight partition; Based on the luminous flux of the backlight partition and the solid angle of each lamp bead in the backlight partition, the light intensity of each lamp bead in the backlight partition is determined, and the light intensity of the lamp bead is the luminous flux emitted within a unit solid angle in a specified direction.

7. The backlight driving method according to claim 6, characterized in that: The step of determining the driving parameters of each lamp bead according to the light intensity of each lamp bead comprises: Configuring the driving parameters includes luminous time and luminous current; According to the light intensity of each lamp bead, the light emitting time and / or light emitting current of each lamp bead are determined.

8. The backlight driving method according to any one of claims 1 to 7, characterized in that: The backlight driving method further comprises: Constructing the same backlight partition to have one or more lamp beads; Each lamp in the same backlight partition is configured to have the same driving parameters.

9. A liquid crystal display device, characterized in that: The liquid crystal display device executes the backlight driving method according to any one of claims 1 to 8.

Images