Patent Application
20120032990
1. Field of the Invention
The present invention relates to a display device and more particularly to a display device, display controlling module which are capable of adjusting the brightness of a backlight module and the display data.
2. Description of Related Art
In recent years, since luminescence efficiency of light emitting diodes (LEDs) has been constantly upgraded, fluorescent lamps and incandescent bulbs are gradually replaced with the LEDs in some fields, such as a light source of a scanner which requires high reaction speed, a backlight source of a liquid crystal display (LCD), car dashboard illumination, traffic signs and general illumination devices. As for using the LEDs as the backlight source, the concept of the local dimming is added into the backlight source controlling process in order to decrease the power consumption of the backlight source and increase the dynamic contrast of the image.
Generally, the local dimming is applied onto the display panel which is divided into several display regions and the LEDs of the backlight module are divided into several light emitting groups for providing the necessary planar light sources respectively for the display regions. The brightness of the emitted light from each of the light emitting groups is adjusted according to the corresponding display regions. Hence, the brightness of the display regions is different from each other so that each of the display regions is interfered by the adjacent light emitting group, which leads to incorrect brightness of the displayed image.
In the current technology, only the display data corresponding to the edges of each of the display regions is adjusted according to the brightness of the light emitting groups adjacent to each of the edge pixels so as to decrease the interference of the adjacent light emitting groups. However, the display data mentioned above is adjusted only according to the brightness of the adjacent light emitting groups. Since the display panel is affected by each of the light emitting groups, the aforementioned adjustment of the display data is not thorough and the image is displayed with flaws.
The invention provides a display device, a display controlling module which are capable of obtaining the interferences respectively corresponding to the display data according to the brightness of each of the light emitting groups and adjusting the display data according to the interferences to eliminate the optical interference of the light emitting groups not corresponding to the display regions. Moreover, according to the grayscale distributions of the display regions, the brightness of the emitted light of the light emitting groups corresponding to the display regions are adjusted and the grayscales of the corresponding display data are adjusted.
The invention provides a display controlling module for a display device having a backlight module and a display panel, wherein the backlight module has a plurality of light emitting groups and the display panel has a plurality of display regions. The display controlling module comprises a data analyzing unit, an interference data storage unit and a data adjustment unit. The data analyzing unit receives a plurality of display data of a corresponding frame and analyzes the display data to obtain a plurality of grayscale distributions of the corresponding display regions. The data analyzing unit generates a backlight signal for adjusting a brightness of each of the light emitting groups according to the grayscale distributions. The interference data storage unit is coupled to the data analyzing unit and the interference data storage unit outputs a plurality of interferences of the corresponding display data according to the backlight controlling signal. The data adjustment unit is coupled to the data analyzing unit and the interference data storage unit so as to receive the display data and the interference. According to the interferences, the data adjustment unit adjusts grayscales of the display data.
According to one embodiment of the present invention, each of the interferences is a sum of radiation interceptions of a pixel irradiated by a portion of the light emitting groups which are not corresponding to the pixel to be written by the corresponding display data.
According to one embodiment of the present invention, the data analyzing unit further generates a plurality of data adjusting signals to the data adjustment unit according to the grayscale distributions and the data adjustment unit correspondingly adjusts the grayscales of the display data corresponding to the display regions according to the data adjusting signals.
According to one embodiment of the present invention, the data analyzing unit determines a maximum distributed grayscale of each of the grayscale distributions according to each of the grayscale distributions, determines an adjustment gain corresponding to each of the grayscale distributions according to the maximum distributed grayscale corresponding to each of the grayscale distributions and generates the data adjusting signals according to the adjustment gains of the grayscale distributions.
According to one embodiment of the present invention, the adjustment gain is a ratio of a maximum grayscale to the maximum distributed grayscale.
According to one embodiment of the present invention, a statistic of the maximum distributed grayscale is larger than a threshold.
According to one embodiment of the present invention, the data analyzing unit adjusts the brightness of each of the light emitting groups according to the adjustment gains of the grayscale distributions and accordingly generates the backlight controlling signal.
The present invention further provides a display device including a backlight module, a display panel, and a display controlling module as mentioned above. The backlight module has a plurality of light emitting groups. The display panel is divided into a plurality of display regions corresponding to the light emitting groups. A brightness of each of the light emitting groups is determined by the grayscale distribution of the corresponding display region.
According to one embodiment of the present invention, the backlight module is a side emitting type backlight module.
Accordingly, the invention provides a display device and a display controlling module which are capable of obtaining the interferences respectively corresponding to the display data according to the brightness of each of the light emitting groups and adjusting the display data according to the interferences to eliminate the optical interference of the light emitting groups not corresponding to the display regions.
In order to make the aforementioned and other features and advantages of the invention more comprehensible, embodiments accompanying figures are described in detail below.
The accompanying drawings are included to provide a further understanding of the invention, and are incorporated in and constitute a part of this specification. The drawings illustrate embodiments of the invention and, together with the description, serve to explain the principles of the invention.
The scaler 110 receives a plurality of original display data ODD of a frame and generates a plurality of scaled display data SDD of the frame according to the original display data ODD. The amount of the scaled display data SDD of the frame is corresponding to the amount of the pixels on the display panel 160. That is, each of the scaled display data SDD is corresponding to one pixel so that the scaled display data SDD is written into the corresponding pixel.
After the display controlling module 120 receives the scaled display data SDD of the frame, the grayscale distributions of the display regions 161, 163, 165 and 167 are analyzed according to the scaled display data. According to the grayscale distributions of the display regions 161, 163, 165 and 167, the display controlling module 120 correspondingly adjusts the brightness of each of the light emitting groups BG1, BG2, BG3 and BG4 and accordingly generates a backlight controlling signal BLC to the backlight controller 170, and, meanwhile, the grayscales of the scaled display data SDD corresponding to the display regions 161, 163, 165 and 167 are adjusted. Moreover, the display controlling module 120, according to the interference corresponding to each of the scaled display data SDD, is adjusted to generate a plurality of adjusted display data RDD.
The backlight controller 170 controls the brightness of each of the light emitting groups BG1, BG2, BG3 and BG4 according to the backlight controlling signal BLC. According to the adjusted display data RDD, the timing controller 130 controls the gate driver 150 outputting scanning signal SC to the display panel 160 so as to turn on each row of pixels of the display panel 160. Further, the timing controller 130 controls the source driver 140 outputting driving voltage VD corresponding to the adjusted display data RDD to the turn-on pixels of the display panel 160. When the pixels of the display panel 160 are all written with the driving voltage VD, the display panel 160 displays image with the light from the backlight modules 171 and 173.
It should be noticed that, in other embodiments, the display controlling module 120 can be integrated into the scaler 110 or the timing controller 130, which can be designed by the skilled artisan in the field, and the present invention is not limited by the descriptions made herein.
The interference data storage unit 220 is coupled to the data analyzing unit 210 and the interference data storage unit 220 outputs a plurality of interferences ICV of the corresponding scaled display data SDD according to the backlight controlling signal BLC. The data adjustment unit 230 is coupled to the data analyzing unit 210 and the interference data storage unit 220 so as to receive the scaled display data SDD, the data adjusting signals DRS and the interferences ICV. The data adjustment unit 230 correspondingly adjusts the grayscales of the scaled display data SDD corresponding to the display regions 161, 163, 165 and 167 according to the data adjusting signals DRS, and correspondingly adjusts the grayscales of the scaled display data SDD according to the interferences.
Then, the grayscales from 0 to 160 are expanded to be the grayscales from 0 to 255. That is, each of the grayscales from 0 to 160 is multiplied by a adjustment gain of 1.6 (which is about 255/160). In other words, the original grayscale of each of the scaled display data SDD is multiplied by the adjustment gain of 1.6 so that the range of the grayscale distribution is equal to the grayscales from 0 to 255 and the grayscale distribution is shown in
Since the original grayscales corresponding the statistics are in a range from 0 to 160, some of the grayscales do not correspond to statistics after the original grayscales are expanded. After the original grayscales are expanded, the brightness of each of the scaled display data SDD is increased. In order that the display panel 160 displays the brightness of the original scaled display data SDD, the brightness of the corresponding light emitting group (i.e. BG1) is adjusted. For instance, when the brightness of the light emitting group BG1 is predetermined to be 100%, the brightness of the light emitting group BG1 can be adjusted to be 62.5% (i.e. 100%/1.6). Thus, not only the brightness of the original frame can be maintained but also the brightness of the light emitting group BG1 can be reduced to decrease the power consumption of the light emitting groups.
In addition, it is not easy to perceive the brightness variation of the relatively brighter portion of the frame. That is, it is not easy to perceive the grayscale difference between portions with the high grayscales. Hence, as shown in
When the frame is displayed, the light emitting diodes L11˜L14 provide the required planar light source to the pixels A11˜Anm. However, the planar light source provided by the light emitting diodes L11˜L14 generates optical interferences to the pixels B11˜Bnm, C11˜Cnm and D11˜Dnm. Similarly, the light emitting diodes L21˜L24 provide the required planar light source to the pixels B11˜Bnm. However, the planar light source provided by the light emitting diodes L21˜L24 generates optical interferences to the pixels A11˜Anm, C11˜Cnm and D11˜Dnm. Accordingly, each of the light emitting groups provides the required planar light source to the corresponding display region but also generates optical interference to other display regions. Hence, the light emitting groups BG1, BG2, BG3 and BG 4 are turned on sequentially so that the radiation interceptions of each of the pixels (such as A11˜Anm, B11˜Bnm, C11˜Cnm and D11˜Dnm) irradiated by the light emitting groups which are not corresponding to the target pixel is measured.
During the measurement, the brightness of the light emitting groups BG1, BG2, BG3 and BG4 is classified into x levels and the grayscale of each of the pixels A11˜Anm, B11˜Bnm, C11˜Cnm and D11˜Dnm is set to be 255. That is, the pixels A11˜Anm, B11˜Bnm, C11˜Cnm and D11˜Dnm are completely transparent. When the brightness of the light emitting groups BG1 is at level of 1, the radiation interception of the pixel B11 is f(B11,BG1,1), the radiation interception of the pixel B12 is f(B12,BG1,1), and others follow the same rules. Moreover, the representations of the radiation interceptions of the pixels C11˜Cnm and D11˜Dnm are similar to the aforementioned description and are not detailed herein. When the brightness of the light emitting groups BG1 is at level of 2, the radiation interception of the pixel B11 is f(B11,BG1,2), the radiation interception of the pixel B12 is f(B12,BG1,2), and others follow the same rules. When the brightness of the light emitting groups BG1 is at level of x, the radiation interception of the pixel B11 is f(B11,BG1,x), the radiation interception of the pixel B12 is f(B12,BG1,x), and others follow the same rules. When the brightness of the light emitting group BG1 is at other level, the radiation interceptions of the pixels can be obtain by following the aforementioned rule and are not detailed herein.
Thereafter, when the light emitting group BG2 is at different brightness level, the radiation interceptions of the pixels A11˜Anm, C11˜Cnm and D11˜Dnm are measured. When the light emitting group BG3 is at different brightness level, the radiation interceptions of the pixels A11˜Anm, B11˜Bnm and D11˜Dnm are measured. When the light emitting group BG4 is at different brightness level, the radiation interceptions of the pixels A11˜Anm, B11˜Bnm and C11˜Cnm are measured. The radiation interceptions measured above can be stored in the interference data storage unit 220 shown in
As shown in
In addition, since the grayscale of the pixel is set to be 255 during the measurement and the grayscales of the pixels are different from each other according the scaled display data SDD during the frame is displayed, the adjusted grayscale can be further changed according to the displayed grayscale. When the grayscale of the scaled display data SDD is 150, the adjusted grayscale is: 2×150/255=1.17 (which is rounded up or down to one grayscale). That is, the scaled display data is further adjusted to be 149 so that the optical interference of the light emitting group which is not corresponding to the measured pixel can be decreased.
Accordingly, the above embodiment can be integrated as a display controlling method for the display controlling module 120.
Accordingly, the embodiment of the invention provides a display device and a display controlling module which are capable of obtaining the interferences respectively corresponding to the scaled display data according to the brightness of each of the light emitting groups and adjusting the scaled display data according to the interferences to eliminate the optical interference of the light emitting groups not corresponding to the display regions. Moreover, according to the grayscale distributions of the display regions, the brightness of the emitted light of the light emitting groups corresponding to the display regions are adjusted and the grayscales of the corresponding scaled display data are adjusted. Thus, when the maximum distributed grayscale is not equal to the maximum grayscale, the brightness of the light emitting group can be reduced to decrease the power consumption of the light emitting groups.
Although the invention has been described with reference to the above embodiments, it will be apparent to one of the ordinary skill in the art that modifications to the described embodiment may be made without departing from the spirit of the invention. Accordingly, the scope of the invention will be defined by the attached claims not by the above detailed descriptions.
| Number | Date | Country | Kind |
|---|---|---|---|
| 99126477 | Aug 2010 | TW | national |
This is a continuation application of and claims the priority benefit of patent application Ser. No. 12/940,055, filed on Nov. 5, 2010, now pending, which claims the priority benefit of Taiwan application serial no. 99126477, filed on Aug. 9, 2010. The entirety of each of the above-mentioned patent applications is hereby incorporated by reference herein and made a part of this specification.
| Number | Date | Country | |
|---|---|---|---|
| Parent | 12940055 | Nov 2010 | US |
| Child | 12947808 | US |
