CIRCUITRY, LOCAL DIMMING CONTROL METHOD AND DISPLAY APPARATUS
A circuitry for controlling a backlight module, the circuitry includes a local dimming control circuit and a backlight control circuit. The local dimming control circuit is configured to generate local dimming data based on image data and an arrangement of a plurality of light emitting units of the backlight module, in which the local dimming data includes a first local dimming data corresponding to a first light emitting unit of the plurality of light emitting units and a second local dimming data corresponding to a second light emitting unit of the plurality of light emitting units, and the number of bits of the first local dimming data is different from the number of bits of the second local dimming data. The backlight control circuit is configured to control the backlight module to irradiate backlight based on the local dimming data.
The invention relates to local dimming, and more particularly to a circuitry and a local dimming control method for a backlight module and a display apparatus with local dimming functionality.
Description of Related ArtA conventional liquid crystal display (LCD) device normally includes a backlight module for providing a backlight source in order to display images. Furthermore, a local dimming technology may be applied to the backlight module to increase the contrast of the LCD device, in which the backlight brightness of specific parts are determined according to the gray level distribution of an image to be displayed. In some examples, for displaying a high gray level portion of an image, the corresponding part of the backlight module will output light with relatively high brightness; for displaying a low gray level portion of an image, the corresponding part of the backlight module will output light with relatively low brightness. However, in order to deal with more and more specific parts of the backlight module and higher screen display frequency (e.g. 90/120/240 Hertz), how to save the amount of local dimming data for transmission is one of the important issues for the industries.
SUMMARYOne aspect of the invention directs to circuitry for controlling a backlight module, the circuitry includes a local dimming control circuit and a backlight control circuit. The local dimming control circuit configured to generate local dimming data based on image data and an arrangement of a plurality of light emitting units of the backlight module, wherein the local dimming data includes a first local dimming data corresponding to a first light emitting unit of the plurality of light emitting units and a second local dimming data corresponding to a second light emitting unit of the plurality of light emitting units, and wherein the number of bits of the first local dimming data is different from the number of bits of the second local dimming data. The backlight control circuit configured to control the backlight module to irradiate backlight based on the local dimming data.
In accordance with one or more embodiments of the invention, each of the first and second local dimming data includes an indication bit, and the indication bits of the first and second local dimming data are of opposite bit values.
In accordance with one or more embodiments of the invention, the first local dimming data has most significant bits and least significant bits, and the second local dimming data only has least significant bits.
In accordance with one or more embodiments of the invention, the local dimming control circuit is further configured to provide a first indication signal for indicating the backlight control circuit to combine the most significant bits of the first local dimming data and the least significant bits of the second local dimming data into a combined second local dimming for the second light emitting unit.
In accordance with one or more embodiments of the invention, the local dimming control circuit is further configured to provide a second indication signal for notifying the backlight control circuit of the number of least significant bits of each of the first and second local dimming data.
In accordance with one or more embodiments of the invention, the backlight control circuit comprises a memory that stores the most significant bits of the first local dimming data.
In accordance with one or more embodiments of the invention, the local dimming data further includes a third local dimming data corresponding to a third light emitting unit of the light emitting units, and the number of bits of the third local dimming data is the same as the number of bits of the second local dimming data and less than the number of bits of the first local dimming data.
In accordance with one or more embodiments of the invention, each of the first to third local dimming data includes an indication bit, the indication bits of the first and second local dimming data are of opposite bit values, and the indication bits of the second and third local dimming data are of the same bit value.
In accordance with one or more embodiments of the invention, the first local dimming data has most significant bits and least significant bits, and each of the second and third local dimming data only has least significant bits.
In accordance with one or more embodiments of the invention, the local dimming control circuit is further configured to transmit an initial code data to the backlight control circuit subsequent to the local dimming data for refreshing an original initial code stored in the backlight control circuit.
Another aspect of the invention is directed to a local dimming control method for a backlight module. The local dimming control method includes: generating local dimming data based on image data and an arrangement of a plurality of light emitting units of the backlight module; and transmitting the local dimming data to a backlight control circuit that controls the backlight module to irradiate backlight accordingly. The local dimming data including a first local dimming data corresponding to a first light emitting unit of the plurality of light emitting units and a second local dimming data corresponding to a second light emitting unit of the plurality of light emitting units. The number of bits of the first local dimming data is different from the number of bits of the second local dimming data.
A further aspect of the invention is directed to a display apparatus which includes a display panel, a backlight module, a local dimming control circuit and a backlight control circuit. The display panel is configured to display an image based on image data. The backlight module has light emitting units, and is configured to provide backlight for the display panel to display the image. The local dimming control circuit is configured to generate local dimming data based on the image data and an arrangement of the plurality of light emitting units. The backlight control circuit is configured to control the backlight module to irradiate the backlight based on the local dimming data. The local dimming data includes a first local dimming data corresponding to a first light emitting unit of the plurality of light emitting units and a second local dimming data corresponding to a second light emitting unit of the plurality of light emitting units, and the number of bits of the first local dimming data is different from the number of bits of the second local dimming data.
The foregoing aspects and many of the accompanying advantages of this invention will become more readily appreciated as the same becomes better understood by reference to the following detailed description, when taken in conjunction with the accompanying drawings.
The detailed explanation of the invention is described as following. The described preferred embodiments are presented for purposes of illustrations and description, and they are not intended to limit the scope of the invention.
Terms used herein are only used to describe the specific embodiments, which are not used to limit the claims appended herewith. Unless limited otherwise, the term “a,” “an,” “one” or “the” of the single form may also represent the plural form. Further, the spatially relative terms are intended to encompass different orientations of the device in use or operation in addition to the orientation depicted in the figures. The apparatus may be otherwise oriented (rotated 90 degrees or at other orientations) and the spatially relative descriptors used herein may likewise be interpreted accordingly.
In the following description and claims, the term “coupled” along with their derivatives, may be used. In particular embodiments, “coupled” may be used to indicate that two or more elements are in direct physical or electrical contact with each other, or may also mean that two or more elements may not be in direct contact with each other. “Coupled” may still be used to indicate that two or more elements cooperate or interact with each other.
The document may repeat reference numerals and/or letters in the various examples. This repetition is for the purpose of simplicity and clarity and does not in itself dictate a relationship between the various embodiments and/or configurations discussed.
The timing controller 140 is also configured to direct the backlight control circuit 150 to control the backlight module 160. The backlight control circuit 150 may be implemented as a microcontroller. The backlight module 160 is arranged in back of the LCD panel 110 for providing light source to the LCD panel 110. The backlight module 160 may be a direct type backlight module 160 in which light source is arranged at the back side thereof and no light guide plate is needed.
In some embodiments, the data driver 120, the scan driver 130 and the timing controller 140 are integrated into a single integrated chip. Furthermore, in certain embodiments, the chip integrating the functions of the data driver 120, the scan driver 130 and the timing controller 140 may also provide touch detection function for the LCD panel 110 with an in-cell touch sensor structure or a touch panel disposed over the LCD panel 110.
It is noted that the scanning pattern of the backlight module 160 is not limited to that shown in
In specific, the local dimming control circuit 142 firstly generates original local dimming data DIM(1)-DIM(N) with equal bit length. Each original local dimming data DIM(1)-DIM(N) includes most significant bits and least significant bits. That is, the original local dimming data DIM(1) includes most significant bits MSB_DATA(1) and least significant bits LSB_DATA(1), the original local dimming data DIM(2) includes most significant bits MSB_DATA(2) and least significant bits LSB_DATA(2), and the like. In some embodiments, for each original local dimming data DIM(1)-DIM(N), the number of each of most and least significant bits is 8. After the original local dimming data DIM(1)-DIM(N) are generated, the dimming control circuit 140 adds an indication bit CBit of “1” to the original local dimming data DIM(1) with the most significant bits MSB_DATA(1) and the least significant bits LSB_DATA(1) to form the local dimming data LD(1) for being transmitted to the backlight control circuit 150, and then compares the original local dimming data DIM(i−1) and DIM(i) for all i from 2 to N. If the most significant bits MSB_DATA(i−1) and MSB_DATA(i) of the original local dimming data DIM(i−1) and DIM(i) are identical, the most significant bits MSB_DATA(i) of the original local dimming data DIM(i) are removed, and an indication bit CBit of “0” is added to the least significant bits LSB_DATA(i) of the original local dimming data DIM(i) to form the local dimming data LD(i) for being transmitted to the backlight control circuit 150. Otherwise, if the most significant bits MSB_DATA(i−1) and MSB_DATA(i) of the original local dimming data DIM(i−1) and DIM(i) are not identical, an indication bit CBit of “1” is added to the original local dimming data DIM(i) with the most significant bits MSB_DATA(i) and the least significant bits LSB_DATA(i) to form the local dimming data LD(i) for being transmitted to the backlight control circuit 150.
For example, in a case where the most significant bits MSB_DATA(1) and MSB_DATA(2) of the original local dimming data DIM(1) and DIM(2) are identical, the local dimming control circuit 142 removes the most significant bits MSB_DATA(2) of the original local dimming data DIM(2), and an indication bit CBit of “0” is added to the least significant bits LSB_DATA(2) of the original local dimming data DIM(2) to form the local dimming data LD(2); in a case where the most significant bits MSB_DATA(3) and MSB_DATA(4) of the original local dimming data DIM(3) and DIM(4) are not identical, an indication bit CBit of “1” is added to the original local dimming data DIM(4) to form the local dimming data LD(4).
In particular, the first indication signal ID1 is used to indicate the backlight control circuit 150 of whether the bits of the currently received local dimming data are reduced from those of the original local dimming data corresponding to the same light emitting unit. For example, the first indication signal ID1 at high indicates that the bits of the currently received local dimming data are the same as those of the original local dimming data corresponding to the same light emitting unit, and when receiving such first indication signal ID1, the backlight control circuit stores the most significant bits of the currently received local dimming data; the first indication signal ID1 at low indicates that the bits of the currently received local dimming data are reduced from those of the original local dimming data corresponding to the same light emitting unit, i.e., the currently received local dimming data only have least significant bits, and when receiving such first indication signal ID1, the backlight control circuit combines the last stored most significant bits and the currently received local dimming data into a combined local dimming data for the same light emitting unit.
For example, in a case where the most significant bits MSB_DATA(1) and MSB_DATA(2) of the original local dimming data DIM(1) and DIM(2) are identical, as shown in
In particular, the second indication signal ID2 is used to indicate the backlight control circuit 150 of the number of bits of the least significant bits in each local dimming data. For example, the second indication signal ID2 at high indicates that the number of most significant bits of each local dimming data is 10 and the number of least significant bits of each local dimming data is 6, while the second indication signal ID2 at low indicates that the number of most significant bits and the number of least significant bits of each local dimming data are all 8. It is noted that the number of most significant bits and the number of least significant bits of each local dimming data herein are merely exemplarily examples and can be determined according to various design parameters and application requirements.
In the example shown in
It will be apparent to those skilled in the art that various modifications and variations can be made to the structure of the invention without departing from the scope or spirit of the invention. In view of the foregoing, it is intended that the invention cover modifications and variations of this invention provided they fall within the scope of the following claims.
Claims
1. A circuitry for controlling a backlight module, the circuitry comprising:
- a local dimming control circuit configured to generate local dimming data based on image data and an arrangement of a plurality of light emitting units of the backlight module, wherein the local dimming data includes a first local dimming data corresponding to a first light emitting unit of the plurality of light emitting units and a second local dimming data corresponding to a second light emitting unit of the plurality of light emitting units, and wherein the number of bits of the first local dimming data is different from the number of bits of the second local dimming data, the first local dimming data has most significant bits and least significant bits, and the second local dimming data only has least significant bits; and
- a backlight control circuit configured to control the backlight module to irradiate backlight based on the local dimming data,
- wherein the local dimming control circuit is further configured to provide an indication signal for indicating the backlight control circuit to combine the most significant bits of the first local dimming data and the least significant bits of the second local dimming data into a combined second local dimming data for the second light emitting unit.
2. The circuitry of claim 1, wherein each of the first and second local dimming data includes an indication bit, and wherein the indication bits of the first and second local dimming data are of opposite bit values.
3-5. (canceled)
6. The circuitry of claim 1, wherein the backlight control circuit comprises a memory that stores the most significant bits of the first local dimming data.
7. The circuitry of claim 1, wherein the local dimming data further includes a third local dimming data corresponding to a third light emitting unit of the plurality of light emitting units, and wherein the number of bits of the third local dimming data is the same as the number of bits of the second local dimming data and less than the number of bits of the first local dimming data.
8. The circuitry of claim 7, wherein each of the first to third local dimming data includes an indication bit;
- wherein the indication bits of the first and second local dimming data are of opposite bit values, and the indication bits of the second and third local dimming data are of the same bit value.
9. (canceled)
10. The circuitry of claim 1, wherein the local dimming control circuit is further configured to transmit an initial code data to the backlight control circuit subsequent to the local dimming data for refreshing an original initial code data stored in the backlight control circuit.
11-19. (canceled)
20. A display apparatus comprising:
- a display panel configured to display an image based on image data;
- a backlight module configured to provide backlight for the display panel to display the image, the backlight module having a plurality of light emitting units;
- a local dimming control circuit configured to generate local dimming data based on the image data and an arrangement of the plurality of light emitting units; and
- a backlight control circuit configured to control the backlight module to irradiate the backlight based on the local dimming data;
- wherein the local dimming data includes a first local dimming data corresponding to a first light emitting unit of the plurality of light emitting units and a second local dimming data corresponding to a second light emitting unit of the plurality of light emitting units, and wherein the number of bits of the first local dimming data is different from the number of bits of the second local dimming data, the first local dimming data has most significant bits and least significant bits, and the second local dimming data only has least significant bits,
- wherein the local dimming control circuit is further configured to provide an indication signal for indicating the backlight control circuit to combine the most significant bits of the first local dimming data and the least significant bits of the second local dimming data into a combined second local dimming data for the second light emitting unit.
21. A circuitry for controlling a backlight module, the circuitry comprising:
- a local dimming control circuit configured to generate local dimming data based on image data and an arrangement of a plurality of light emitting units of the backlight module, wherein the local dimming data includes a first local dimming data corresponding to a first light emitting unit of the plurality of light emitting units and a second local dimming data corresponding to a second light emitting unit of the plurality of light emitting units, and wherein the number of bits of the first local dimming data is different from the number of bits of the second local dimming data, the first local dimming data has most significant bits and least significant bits, and the second local dimming data only has least significant bits; and
- a backlight control circuit configured to control the backlight module to irradiate backlight based on the local dimming data,
- wherein the local dimming control circuit is further configured to provide an indication signal for notifying the backlight control circuit of a number of the least significant bits of each of the first and second local dimming data.
Type: Application
Filed: Jul 2, 2020
Publication Date: Jan 6, 2022
Inventors: Chih-Ying LIN (Tainan City), Chia-Wei TSAI (Tainan City)
Application Number: 16/919,117