CN101231810A - Frequency adjusting circuit, method and display device comprising frequency adjusting circuit - Google Patents

Abstract

A frequency adjusting circuit, a method and a display device comprising the frequency adjusting circuit are provided. The display device is used for displaying a picture and comprises a frequency adjusting circuit, a source electrode driving circuit and a display panel. The frequency adjusting circuit stores the picture by a plurality of display blocks, respectively calculates the gray scale average value of each display block, and outputs a plurality of control signals according to the comparison result of the gray scale average values and at least one threshold value. The source driving circuit adjusts the frequency of the common electrode signal of the display block according to the control signal. Finally, the display panel displays the plurality of display blocks according to the adjusted frequency of the common electrode signal. The invention has the advantages of low power consumption and excellent image display quality.

Description

Frequency adjustment circuit, method and display device including the frequency adjustment circuit

technical field

The present invention relates to a frequency adjustment circuit, a method, and a display device including the frequency adjustment circuit; more specifically, it relates to a frequency adjustment circuit, a method, and a frequency adjustment circuit that can dynamically adjust the frequency of a common electrode signal of a source drive circuit, and includes the frequency adjustment circuit. Display device for frequency adjustment circuit.

Background technique

In recent years, flat panel displays have developed more and more rapidly, and have gradually replaced traditional cathode ray tube displays. Today's flat panel displays mainly include the following types: Organic Light-Emitting Diodes Display (OLED), Plasma Display Panel (PDP), Liquid Crystal Display (LCD), and Field Emission Display ( Field Emission Display; FED), etc. Among them, liquid crystal displays have become the mainstream of today's consumer displays, especially due to their low power consumption, thinness, and high resolution.

Not only that, but also due to the rapid progress of manufacturing technology of liquid crystal displays, liquid crystal displays have many advantages, such as lightness, thinness, power saving and low radiation. Due to the above characteristics, liquid crystal displays have been widely used in various electronic products, such as personal digital assistants (Personal Digital Assistant; PDA), notebook computers, digital cameras, digital video cameras, mobile phones, computer screens and LCD TVs. wait.

In order to further meet the needs of various different aspects, such as better display quality or lower power consumption, etc. Many types of driving methods, such as line inversion (Line Inversion) driving method or field inversion (frame inversion) driving method, etc. have been developed and applied by LCD manufacturers. However, the above methods still have their own disadvantages.

For example, although the power consumption of the liquid crystal display using the field inversion driving method for image display is low enough to meet the display requirements of mobile devices, it results in poor image display quality. Although the liquid crystal display using the line inversion driving method for image display has better image display quality, its relatively large power consumption has become a major disadvantage, which in turn causes problems such as power consumption that are difficult to overcome.

To sum up, it is an urgent goal for the industry to produce a display device with low power consumption and good image display quality.

Contents of the invention

Based on the aforementioned problems faced by the prior art, an object of the present invention is to provide a display device for displaying pictures. The display device is used for displaying images and includes a frequency adjustment circuit, a source driving circuit and a display panel. The frequency adjustment circuit stores the picture in a plurality of display blocks, calculates the gray scale average value of each display block respectively, and outputs multiple control signals according to the comparison result between the multiple gray scale average values and at least one threshold value. The source driving circuit adjusts the frequency of the common electrode signal of the display block according to the control signal. Finally, the display panel displays the plurality of display blocks according to the frequency of the adjusted common electrode signal.

In more detail, the above-mentioned frequency adjustment circuit further includes a storage unit and a core processing unit. The storage unit is used for receiving the picture and storing the picture in a plurality of display blocks. The core processing unit respectively calculates the gray scale average value of each of the display blocks, and compares the gray scale average values of the plurality of display blocks with thresholds to generate a plurality of comparison results.

The aforementioned core processing unit may display multiple control signals according to the multiple comparison results.

Another object of the present invention is to provide a frequency adjustment method for adjusting the frequency of the common electrode signal. The method includes the following steps: receiving a picture, the picture includes a plurality of display blocks, each of which includes a plurality of pixel data; storing the plurality of pixel data in the plurality of display blocks; according to the plurality of display blocks, Calculate the gray scale average value of each display block from pixel data respectively; and compare the gray scale average value of the plurality of display blocks with the first threshold value respectively. The frequency of the common electrode signal corresponding to each of the display blocks is adjusted according to the aforementioned multiple comparison results, and each display block is further displayed according to the frequency of the adjusted common electrode signal.

In the above-mentioned frequency adjustment method, when the grayscale average value of the plurality of display blocks in the plurality of comparison results is greater than the first threshold, the following steps may also be included: outputting a first control signal; and

According to the first control signal, the frequency of the common electrode signal corresponding to the display block is adjusted to a first frequency; wherein, the display block is displayed according to the first frequency.

In the above-mentioned frequency adjustment method, when the gray scale average value of the plurality of display blocks in the plurality of comparison results is not greater than the first threshold, the following steps may also be included: outputting a second control signal; and according to the The second control signal adjusts the frequency of the common electrode signal corresponding to the display block to a second frequency; wherein, the display block is displayed according to the second frequency.

The above-mentioned frequency adjustment method may further include the following step: comparing the average gray levels of the plurality of display blocks with a second threshold.

The above-mentioned frequency adjustment method may further include the following steps: when the gray scale average value of the plurality of display blocks is not greater than the first threshold and greater than the second threshold, outputting a second control signal; and according to the second control signal, adjusting the frequency of the common electrode signal corresponding to the display block to a second frequency; wherein, the display block is displayed according to the second frequency.

The above-mentioned frequency adjustment method may further include the following steps: when the gray scale average value of the plurality of display blocks is not greater than the second threshold, outputting a third control signal; and according to the third control signal, corresponding to the The frequency of the common electrode signal of the display block is adjusted to a third frequency; wherein, the display block is displayed according to the third frequency.

In the above frequency adjustment method, the second frequency may be a preset frequency of the common electrode signal.

Another object of the present invention is to provide a frequency adjustment circuit for adjusting the frequency of the common electrode signal. The frequency adjustment circuit includes: a storage unit, used to receive a picture with a plurality of pixel data, and store the plurality of pixel data in a plurality of display blocks; and a core processing unit, used to calculate the plurality of displaying the gray scale average value of the block, and comparing the gray scale average value with the first threshold value to generate a plurality of comparison results; wherein, the core processing unit adjusts the gray scale value corresponding to each display block according to the multiple comparison results The frequency of the common electrode signal, and each of the display blocks is displayed according to the frequency of the adjusted common electrode signal.

In the above frequency adjustment circuit, the core processing unit can also compare the average value of the gray scale with the second threshold.

The present invention analyzes the average gray levels of different display blocks in the picture, and compares the average gray levels of these display blocks with various thresholds. Accordingly, the frequency of the common electrode signal of different display blocks in the screen is adjusted, and the goal of a display device with low power consumption and good image display quality is achieved by dynamically adjusting the frequency of the common electrode signal.

After referring to the accompanying drawings and the implementations described later, those skilled in the art can understand other objectives of the present invention, as well as the technical means and implementations of the present invention.

Description of drawings

Fig. 1 is the schematic diagram of the first embodiment of the present invention;

2 is a schematic diagram of the frequency of the picture 21 and the common electrode signal displayed by the display panel of the first embodiment; and

Fig. 3 is a flowchart of the second embodiment of the present invention.

Wherein, the reference signs are explained as follows:

1: Liquid crystal display device 10: Screen data

11: Gate controller 12: Gate drive signal

13: Gate drive circuit 14: First control signal

15: Frequency adjustment circuit 16: Second control signal

17: Source drive circuit 18: The third control signal

19: Display panel 151: Storage unit

153: Core processing unit 20, 22, 24: Frequency waveform of common electrode signal

21: Screen 211: The first block

213: The second block 215: The third block

Detailed ways

As shown in FIG. 1 , the first embodiment of the present invention is a liquid crystal display device 1 , which includes a gate controller 11 , a gate drive circuit 13 , a frequency adjustment circuit 15 , a source drive circuit 17 and a display panel 19 . The display panel 19 includes a plurality of pixels (not shown). The gate controller 11 is used for receiving frame data 10 , and the frame data 10 includes a plurality of pixel data, which are respectively input to pixels of the display panel 19 , so that the display panel 19 displays a frame. After the gate controller 11 processes the frame data 10 , it will generate a gate driving signal 12 . The gate driving circuit 13 receives the gate driving signal 12 to control the on and off of the pixels of the display panel 19 . Those of ordinary skill in the technical field of the present invention should be able to understand the operations and functions of the gate controller 11 and the gate driving circuit 13 , so details will not be repeated here.

The frequency adjustment circuit 15 further includes a storage unit 151 and a core processing unit 153 . After the frequency adjustment circuit 15 receives the frame data 10 , the storage unit 151 stores the pixel data in the frame data 10 in a plurality of display blocks. Subsequently, the storage unit 151 transmits the pixel data of these display blocks to the core processing unit 153 respectively. The core processing unit 153 calculates the gray scale averages of different display blocks according to the pixel data of these display blocks. And output different control signals 14 , 16 , 18 to the source driving circuit 17 according to the gray scale average value of these display blocks. The source driving circuit 17 changes the frequency of the common electrode signal of different display blocks according to these control signals 14 , 16 , 18 to achieve the purpose of dynamically adjusting the frequency of the common electrode signal.

The following will describe in detail how the core processing unit 153 outputs the control signal according to the gray scale average value of different display blocks. The core processing unit 153 compares the average gray levels of these different display blocks with a threshold. For example, for 6-bit data (0-63), the 56th grayscale can be regarded as the first threshold (not shown in the figure); and the 8th grayscale can be regarded as the second threshold (not shown in the figure).

As shown in FIG. 2 , it is a schematic diagram of the frequency of the picture 21 displayed on the display panel and the common electrode signal. In this embodiment, the screen 21 is divided into three display blocks 211 , 213 , 215 , and the storage unit 151 stores pixel data of these display blocks 211 , 213 , 215 respectively. It should be noted that the present invention does not limit the number of display blocks in the screen 21 , those skilled in the art can increase the number of display blocks in the screen 21 according to requirements, so details are not repeated here. Subsequently, the core processing unit 153 calculates the gray scale average value of these display blocks 211, 213, 215 respectively, and compares the gray scale average value of the display block 211 with the first threshold and the second threshold; the display block 213 The average grayscale of the display block 215 is compared with the first threshold and the second threshold; and then the average grayscale of the display block 215 is compared with the first threshold and the second threshold.

If the grayscale averages of the display blocks 211, 213, and 215 are all within the first threshold (the 56th grayscale) and the second threshold (the 8th grayscale), the core processing unit 153 outputs the second control signal 16 to Source drive circuit 17. The source driving circuit 17 outputs the second control signal 16 to the source driving circuit 17 to control the frequency of the common electrode signal of all the display blocks 211 , 213 , 215 of the frame 21 to be the second frequency. Accordingly, the frequency of the common electrode signal of the frame 21 will be output like the waveform 20 .

If the average gray scale of the display block 211 is greater than the first threshold (the 56th gray scale); the average gray scale of the display block 213 is less than the second threshold (the eighth gray scale); and the average gray scale of the display block 215 The value still falls between the first threshold and the second threshold. The core processing unit 153 will output the first control signal 14 to the source driver circuit 17 to control the frequency of the common electrode signal of the display block 211 of the screen 21 as the first frequency; output the third control signal 18 to the source driver circuit 17 to The frequency of the common electrode signal controlling the display block 213 of the frame 21 is the third frequency; and the frequency of outputting the second control signal 16 to the source driving circuit 17 to control the display block 215 of the frame 21 is the second frequency. Accordingly, the frequency of the common electrode signal of the frame 21 will be output as a waveform 22 . And the first frequency of the common electrode signal of display block 211 is less than the second frequency of the common electrode signal of display block 215; And the second frequency of the common electrode signal of display block 215 is less than that of the common electrode signal of display block 213 third frequency.

Another example is that the gray scale average value of the display block 211 falls between the first threshold value (the 56th gray scale) and the second threshold value (the 8th gray scale value), while the gray scale average values of the display blocks 213 and 215 are both smaller than the first threshold value (the 56th gray scale value). Two thresholds. The core processing unit 153 will output the second control signal 16 to the source drive circuit 17 to control the frequency of the common electrode signal of the display block 211 of the screen 21 to be the second frequency, and output the third control signal 18 to the source drive circuit 17 The third frequency is the frequency of the common electrode signal of the display blocks 213 and 215 of the control screen 21 . Accordingly, the frequency of the common electrode signal of the frame 21 will be output as a waveform 24 .

It should be noted here that there may be a certain relationship between the first frequency, the second frequency and the third frequency, for example, the value of the second frequency may be N times the value of the first frequency, or the second The value of the frequency may be N times the value of the first frequency 2, wherein N is a positive integer. The second frequency is a preset frequency of the common electrode signal. Moreover, although in the first embodiment, the core processing unit 153 compares the average value of the gray levels of the display blocks 211, 213, and 215 with the first threshold and the second threshold, the frequency of the common electrode signal is dynamically adjusted in three intervals. Adjustment. But the present invention does not limit the number of thresholds in the core processing unit 153 . In other words, the core processing unit of the present invention can compare the grayscale average value of the display block only with the first threshold, or only with the second threshold, and dynamically adjust the frequency of the common electrode signal in two intervals, Those skilled in the art can directly understand how the liquid crystal display device 1 of the present invention performs such operations and functions according to the description in the preceding paragraph, so details are not repeated here.

The second embodiment of the present invention, as shown in FIG. 3 , is a frequency adjustment method for adjusting the frequency of a common electrode signal in a display device. The display device may be the liquid crystal display device 1 described in the first embodiment. The method is described below.

When step 301 is executed, a frame is received, such as the frame 21 described in the first embodiment, the frame includes a plurality of display blocks, and each display block includes a plurality of pixel data. Next, step 303 is executed to store the plurality of pixel data. Step 305 is then executed to calculate the average gray scale of each display block according to the plurality of pixel data. Step 307 is executed to compare the gray scale average value of the display block with the first threshold. Step 309 is then executed to determine whether the gray scale average value of the display block is greater than the first threshold. When the grayscale average value of the display block is greater than the first threshold, step 311 is executed to output a first control signal. Step 313 is then executed to adjust the frequency of the common electrode signal of the display block to the first frequency according to the first control signal.

In step 309, when the gray scale average value of the display block is not greater than the first threshold, step 315 is executed to compare the gray scale average value of the display block with a second threshold value. Step 317 is then executed to determine whether the grayscale average value of the display block is greater than the second threshold. When the grayscale average value of the display block is greater than the second threshold, step 319 is executed to output a second control signal. Step 321 is then executed to adjust the frequency of the common electrode signal of the display block to a second frequency according to the second control signal.

In step 317, when the grayscale average value of the display block is not greater than the second threshold, step 323 is executed to output a third control signal. Step 325 is then executed to adjust the frequency of the common electrode signal of the display block to a third frequency according to the third control signal.

In addition to the above steps, the second embodiment can also perform the operations and functions described in the first embodiment, and those of ordinary skill in the art can directly understand how the second embodiment performs these operations and functions based on the above-mentioned first embodiment, so I won't repeat them here.

With the help of the description in the preceding paragraph, the frequency of the common electrode signal in the present invention can be varied arbitrarily, depending on the content of the image data actually to be displayed. Since the human eye is more sensitive to images with lower brightness, it is less sensitive to images with higher brightness. Therefore, when displaying an image with higher brightness (that is, a higher average gray scale), the common electrode signal with a lower frequency is used; and when displaying an image with lower brightness (that is, a lower average gray scale), Use a higher frequency common electrode signal. In this way, when displaying low-brightness image data, a high-frequency common electrode signal can be used to obtain better image quality; when high-brightness image data is displayed, a lower-frequency common electrode signal can be used. The effect of saving power consumption can be achieved.

The above examples are only used to illustrate the implementation of the present invention and explain the technical features of the present invention, and are not intended to limit the scope of the present invention. Any changes or equivalent arrangements that can be easily accomplished by those skilled in the art to which the present invention belongs belong to the scope of the present invention, and the scope of rights of the present invention should be determined by the claims.

Claims (11)

1. A frequency adjustment method for adjusting the frequency of a common electrode signal, comprising the following steps: receiving a picture, the picture includes a plurality of display blocks, and each display block includes a plurality of pixel data; storing the plurality of pixel data, wherein the plurality of pixel data is stored in the plurality of display blocks; According to the plurality of pixel data, respectively calculate the gray scale average value of each display block; and Comparing the average gray levels of the plurality of display blocks with a first threshold to generate a plurality of comparison results; Wherein, the frequency of the common electrode signal corresponding to each of the display blocks is adjusted according to the plurality of comparison results, and each of the display blocks is displayed according to the frequency of the adjusted common electrode signal. 2. The frequency adjustment method as claimed in claim 1, wherein when the gray scale average value of the plurality of display blocks in the plurality of comparison results is greater than the first threshold, further comprising the following steps: outputting a first control signal; and adjusting the frequency of the common electrode signal corresponding to the display block to a first frequency according to the first control signal; Wherein, the display block is displayed according to the first frequency. 3. The frequency adjustment method as claimed in claim 1, wherein when the gray scale average value of the plurality of display blocks in the plurality of comparison results is not greater than the first threshold, further comprising the following steps: outputting a second control signal; and adjusting the frequency of the common electrode signal corresponding to the display block to a second frequency according to the second control signal; Wherein, the display block is displayed according to the second frequency. 4. The frequency adjustment method as claimed in claim 1, further comprising the following steps: and comparing the average gray levels of the plurality of display blocks with a second threshold. 5. The frequency adjustment method as claimed in claim 4, further comprising the following steps: outputting a second control signal when the grayscale average value of the plurality of display blocks is not greater than the first threshold and greater than the second threshold; and adjusting the frequency of the common electrode signal corresponding to the display block to a second frequency according to the second control signal; Wherein, the display block is displayed according to the second frequency. 6. The frequency adjustment method as claimed in claim 4, further comprising the steps of: outputting a third control signal when the grayscale average value of the plurality of display blocks is not greater than the second threshold; and adjusting the frequency of the common electrode signal corresponding to the display block to a third frequency according to the third control signal; Wherein, the display block is displayed according to the third frequency. 7. The frequency adjustment method as claimed in claim 6, wherein the second frequency is a preset frequency of the common electrode signal. 8. A frequency adjustment circuit, used to adjust the frequency of the common electrode signal, comprising: a storage unit, configured to receive a picture with a plurality of pixel data, and store the plurality of pixel data in a plurality of display blocks; and a core processing unit, configured to calculate the average gray scale of the plurality of display blocks, and compare the average gray scale with a first threshold to generate a plurality of comparison results; Wherein, the core processing unit adjusts the frequency of the common electrode signal corresponding to each of the display blocks according to the plurality of comparison results, and each of the display blocks is displayed according to the adjusted frequency of the common electrode signal. 9. The frequency adjustment circuit as claimed in claim 8, wherein the core processing unit further compares the average value of the gray scale with a second threshold. 10. A display device for displaying a picture comprising a plurality of pixel data, comprising: The frequency adjustment circuit stores the picture in a plurality of display blocks and calculates the gray scale average value of each display block respectively, and outputs a plurality of control signals according to the multiple gray scale average values; a source drive circuit, adjusting the frequency of the common electrode signals of the plurality of display blocks according to the plurality of control signals; and The display panel displays the plurality of display blocks according to the frequency of the adjusted common electrode signal. 11. The display device as claimed in claim 10, wherein the frequency adjustment circuit further comprises: a storage unit, configured to receive the plurality of pixel data, and store the plurality of pixel data in the plurality of display blocks; and The core processing unit calculates the average gray scale of each display block according to the multiple pixel data, and compares the average gray scale of the multiple display blocks with a first threshold to generate multiple comparison results ; Wherein, the core processing unit outputs multiple control signals according to the multiple comparison results.

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