TWI694434B - Adjustment method of display apparatus with dual cells - Google Patents

Abstract

An adjustment method of a display apparatus with dual cells is provided. The display apparatus includes a first cell and a second cell, the first cell is set to a first resolution, and the second cell is set to a second resolution. When the display apparatus receives an original signal, the first cell is set with the original signal and an input signal of the second cell is determined by looking up a table, wherein the input signal includes grayscale values of a plurality of original pixels at the first resolution. When the second resolution is less than the first resolution, a corresponding relationship between the original pixels included in the second resolution and adjusted pixels included in the second cell at the second resolution is calculated to obtain each adjusted pixel including n original pixels. The grayscale value of each adjusted pixel is adjusted between a maximum value and an average value obtained based on the n original pixels corresponding to the respective adjusted pixels.

Description

Method for adjusting display device with double panel

The invention relates to an adjustment method of a display device, and in particular to an adjustment method of a display device with a double panel.

Conventional single liquid crystal panel displays will cause contrast reduction due to light leakage. Therefore, dual liquid crystal panel displays have been proposed to solve the light leakage problem, thereby improving contrast. In general, the combination of the front and rear panels is prone to the problem of misalignment of the front and rear panels. In the case of inaccurate alignment, the text will be blurred. Even if the alignment is accurate, the display of the dual LCD panel will easily see the error information caused by the backplane when looking sideways.

The invention provides an adjustment method of a display device with double panels, which can effectively solve the blurring of text caused by the misalignment of the double panels.

An adjustment method of a display device with a dual panel according to the present invention, wherein the display device includes a first panel and a second panel, the first panel is set to a first resolution, and the second panel is set to a second resolution, the adjustment method includes: When the display device receives the original signal, the first signal is used to set the first panel, and the input signal of the second panel is determined through a look-up table, where the input signal includes grayscale values of a plurality of original pixels at the first resolution; When the second resolution is less than the first resolution, calculate the correspondence between the original pixels included in the second panel at the first resolution and the adjusted pixels included in the second panel at the second resolution , And obtaining each adjusted pixel includes n original pixels, where n is an integer greater than or equal to 2; and between the maximum value and the average value obtained from the n original pixels corresponding to each adjusted pixel, adjust The grayscale value of each adjusted pixel.

In an embodiment of the present invention, between the maximum value and the average value obtained from the n original pixels corresponding to each adjusted pixel, the step of adjusting the grayscale value of each adjusted pixel includes: based on each adjusted N original pixels corresponding to the pixels, calculate the light and dark drop values; compare the light and dark drop values with the first threshold and the second threshold, respectively, where the second threshold is greater than the first threshold; when the light and dark drops When it is greater than the second threshold, the maximum value of the n original pixels is used as the grayscale value of the adjusted pixel; when the light and dark drop value is less than the first threshold, the average value of the n original pixels is used as the adjusted pixel The corresponding grayscale value; and when the difference between the light and dark values is greater than or equal to the first threshold value and less than or equal to the second threshold value, the interpolated value is used as the grayscale value corresponding to the adjusted pixel.

In an embodiment of the present invention, based on the n original pixels corresponding to each adjusted pixel, the step of calculating the bright and dark drop value includes: calculating the bright and dark drop value based on the maximum value and the minimum value of the n original pixels .

In an embodiment of the present invention, after the step of adjusting the grayscale value of each adjusted pixel, the method further includes: performing blurring adjustment on the grayscale value of each adjusted pixel of the second panel by using a filter. The blurring adjustment includes: setting the filter, wherein the filter includes M×N block pixels, the size of each block pixel corresponds to the size of each of the adjusted pixels, and M×N areas The blocks have corresponding coefficients, and the M×N coefficients add up to 1; the center block of the block pixels of the filter is aligned with the adjusted pixels one by one; the adjusted pixels covered by the block pixels After the grayscale values of are added, the grayscale values of the adjusted pixels are blurred based on the coefficients corresponding to the M×N blocks of the filter.

In an embodiment of the invention, the adjustment method of the display device further includes: when the second resolution is equal to the first resolution, using a filter to blur each original pixel in the input signal of the second panel化adjust. The blurring adjustment includes: setting a filter, wherein the filter includes M×N block pixels, the size of each block pixel corresponds to the size of each pixel, and the M×N blocks have corresponding coefficients, And the M×N coefficients add up to 1; use the center block of the block pixels of the filter to align each original pixel one by one; and add the grayscale values of the original pixels covered by the block pixels To blur the grayscale value of each original pixel.

Based on the above, the image quality degradation of the text lines caused by inaccurate alignment or too large gap between the two panels can be effectively improved by reducing the resolution of the second panel.

In order to make the above-mentioned features and advantages of the present invention more obvious and understandable, the embodiments are specifically described below in conjunction with the accompanying drawings for detailed description as follows.

Generally speaking, in a dual liquid crystal panel display device, the combination of the two front and rear panels will cause the problem of pixel alignment deviation between the front and rear, resulting in a situation where the text is blurred. Therefore, the present invention provides an adjustment method for a display device having a dual panel, which can effectively improve the display misalignment problem by adjusting the signal of the second panel. In order to make the content of the present invention clearer, the following specific embodiments are taken as examples on which the present invention can indeed be implemented.

In the following embodiment, the display device has a first panel and a second panel. The first panel is, for example, a front cell, and the second panel is, for example, a back cell. Moreover, the display device has a controller, and the output of the first panel and the second panel is determined by the controller.

FIG. 1 is a flowchart of an adjustment method of a display device with a dual panel according to an embodiment of the invention. Referring to FIG. 1, in step S105, when the display device receives the original signal, the first panel is set with the original signal, and the input signal of the second panel is determined through a look-up table. Here, the first panel is set to the first resolution, and the second panel is set to the second resolution. The input signal of the second panel includes the grayscale values of the original pixels at the first resolution.

The corresponding information between the first panel and the second panel is stored in the display device. After determining the input signal (R, G, B) of the first panel, the input signal of the second panel corresponding to the input signal of the first panel is obtained by looking up the table.

In this embodiment, it is assumed that the second resolution is smaller than the first resolution. Since the resolution of the input signal of the second panel obtained through the table lookup is the first resolution, when the second resolution of the second panel is less than the first resolution, the input signal of the second panel is required Perform the action of lowering the resolution. That is, after determining the input signal of the second panel, in step S110, the original pixels included in the second panel at the first resolution and the adjusted pixels included in the second panel at the second resolution are calculated The corresponding relationship between the obtained pixels includes n original pixels. Here, n is an integer greater than or equal to 2.

Assuming that the first resolution is 1920×1080, the input signal of the second panel includes grayscale values corresponding to 1920×1080 original pixels. And, assuming that the second resolution is 960×540, in step S110, it is calculated that one adjusted pixel corresponds to 4 (2×2) original pixels. As shown in FIG. 3, FIG. 3 is a schematic diagram of the correspondence between the adjusted pixels and the original pixels according to an embodiment of the present invention. In FIG. 3, one adjusted pixel P corresponds to four original pixels P1 to P4. However, this is only an example and not limited to this. In other embodiments, one adjustment pixel P may also correspond to 2, 3, 5 or more original pixels.

Returning to FIG. 1, in step S115, the grayscale value of each adjusted pixel is adjusted between the maximum value and the average value obtained from the n original pixels corresponding to each adjusted pixel. Here is another example to explain in detail how to adjust the grayscale value of each adjusted pixel.

FIG. 2 is a flowchart of a method for adjusting the grayscale value of each adjusted pixel according to an embodiment of the invention. In step S205, the light-dark drop value ΔGray is calculated. That is, the brightness difference ΔGray is calculated based on the n original pixels corresponding to the adjusted pixels. The light-dark fall value ΔGray is calculated based on the maximum and minimum values of n original pixels. In terms of Figure 3, ΔGray = Max(P1, P2, P3, P4) − Min(P1, P2, P3, P4). Among them, Max(P1, P2, P3, P4) represents the maximum value among the grayscale values corresponding to the original pixels P1～P4, and Min(P1, P2, P3, P4) represents among the grayscale values corresponding to the original pixels P1～P4 The minimum value. By subtracting the maximum value from the minimum value, the light-dark difference ΔGray of this adjusted pixel can be obtained.

Next, in step S210, the light-dark difference ΔGray is compared with the first threshold value T1 and the second threshold value T2, respectively. Here, the second threshold value T2 is greater than the first threshold value T1. The setting range of the first threshold T1 is, for example, 10-20, the setting range of the second threshold T2 is, for example, 30-40, and the preferred first threshold T1 is, for example, 15, and the preferred second threshold T2 is, for example 35. However, this is only an example and not limited to this.

When the light-dark fall value ΔGray is smaller than the first threshold value T1, in step S215, the average value of the n original pixels is used as the grayscale value corresponding to the adjusted pixel. When the light-dark difference ΔGray is greater than or equal to the first threshold T1 and less than or equal to the second threshold T2, the interpolated value is used as the grayscale value corresponding to the adjusted pixel. When the light-dark difference ΔGray is greater than the second threshold T2, in step S225, the maximum value of the n original pixels is used as the grayscale value corresponding to the adjusted pixel.

For example, FIG. 4 is a diagram for setting the grayscale value of the adjusted pixel with a value between the maximum value and the average value obtained in n original pixels according to an embodiment of the present invention. Please refer to FIG. 4, the horizontal axis shows the light and dark drop value ΔGray, and the vertical axis shows the gray scale value. Here, the average value Gavg obtained in the n original pixels is set as the minimum value, and the maximum value Gmax obtained in the n original pixels is set as the maximum value.

As shown in Figure 4, when ΔGray>T2, the maximum value Gmax is used as the grayscale value of the adjusted pixel; when ΔGray<T1, the average value Gavg is used as the grayscale value of the adjusted pixel; at T1 When ≤ΔGray≤T2, the interpolation value obtained by interpolating based on the average value Gavg and the maximum value Gmax is used as the grayscale value corresponding to the adjusted pixel.

After adjusting the grayscale values of the adjusted pixels, a filter may be further used to adjust the blurring of the grayscale values of each adjusted pixel of the second panel. Here, the filter is set. This filter includes M×N block pixels, the size of each block pixel corresponds to the size of each adjusted pixel, and the M×N blocks have corresponding coefficients, and the M×N coefficients are added together Equal to 1. The size of the filter can be adjusted according to the actual hardware conditions.

5 is a schematic diagram of a filter according to an embodiment of the invention. As shown in FIG. 5, the filter includes 3×3 block pixels, and the coefficient corresponding to each block pixel is equal to 1 after being summed. In this embodiment, the coefficients corresponding to the pixels of each block are the same. However, in other embodiments, the coefficients corresponding to the pixels of each block may also be different. For example, different block pixels may be given different weights. As shown in FIG. 7, FIG. 7 is a schematic diagram of a filter according to another embodiment of the present invention. In FIG. 7, the filter includes 5×5 block pixels.

After deciding the filter, use the center blocks of these block pixels of the filter to align each adjusted pixel one by one, and blur the gray of each adjusted pixel based on the coefficients corresponding to the M×N blocks of the filter Order value. Below is an example to illustrate how to use the filter to adjust the blur.

6A-6D are schematic diagrams of blurring adjustment using a filter according to an embodiment of the invention. Here, the pixels in a frame can be divided into two parts, one of them is the pixel that is not at the edge of the frame, and the filter F can completely cover multiple pixels corresponding to its size; the other is at the edge of the frame Of pixels, the filter F cannot completely cover multiple pixels corresponding to its size.

The pixel not located at the edge of the frame is illustrated below with FIG. 6C, that is, the filter F can completely cover multiple pixels corresponding to its size. Taking pixel P ₁₂ as an example, the filter F can completely cover 3×3 pixels (P ₀₁ , P ₀₂ , P ₀₃ , P ₁₁ , P ₁₂ , P ₁₃ , P ₂₁ , P ₂₂ corresponding to its 3×3 size , P ₂₃ ). When after the pixel P ₁₂ fuzzification adjustment, _{P 01, P 02, P 03} , P 11, P 12, P 13, P 21, P 22, P 23 of nine pixels of the original gray scale value is added The total number of is multiplied by the coefficients corresponding to the pixels of each block of the filter F to obtain the value of the pixel P ₁₂ after blurring adjustment. Taking FIG. 5 as an example, the value obtained by multiplying the sum of the grayscale values of the above nine pixels by 1/9 (that is, the average value) is used as the value after the pixel P ₁₂ is adjusted for blurring. After that, when the filter F is moved to the right by one pixel to adjust the blurring of the pixel P ₁₃ , P ₀₂ , P ₀₃ , P ₀₄ , P ₁₂ , P ₁₃ , P ₁₄ , P ₂₂ , P ₂₃ , P ₂₄ the total number of the nine pixels of the original gray scale value is added is multiplied by a coefficient for each block of pixels corresponding to the filter F, thereby to obtain the value of pixel P ₁₃ after fuzzification adjusted. By analogy, blur the pixels that are not at the edge of the frame.

In addition, the pixels located at the edge of the frame are illustrated with FIGS. 6A, 6B, and 6D, that is, the filter F cannot completely cover multiple pixels corresponding to its size. In FIG. 6A, when targeting pixel P ₀₀ , the center block of filter F is aligned with pixel P ₀₀ . When blurring adjustment is performed on the pixel P ₀₀ , the average value of the gray-scale values of the four pixels P ₀₀ , P ₀₁ , P ₁₀ , and P ₁₁ is used as the value of the pixel P ₀₀ after the blur adjustment.

In FIG. 6B, when targeting the pixel P ₀₁ , the center block of the filter F is aligned with the pixel P ₀₁ . When blurring adjustment is performed on the pixel P ₀₁ , the average value of the grayscale values of the six pixels P ₀₀ , P ₀₁ , P ₀₂ , P ₁₀ , P ₁₁ and P ₁₂ is used as the blur adjustment of the pixel P ₀₁ value.

In FIG 6D, the pixel for a ₂₇ by P, and the central block is aligned pixel filter F P _27. When blurring of the pixel P is adjusted _27, the average value _{P 16, P 17, P 26} , P 27, P 36, P ₃₇ six gray value pixel P ₂₇ as fuzzy Adjustment value. By analogy, blur the pixels at the edge of the frame.

In addition, in other embodiments, the filter shown in FIG. 7 may be used to perform blur adjustment. For example, when adjusting the blurring for pixels that are not at the edge of the frame, the total number of the original gray levels of the 25 pixels covered by the filter are added, and multiplied by the coefficients corresponding to the pixels of each block of the filter In order to obtain the value after the blur adjustment of the pixel corresponding to the center block of the filter. In the case of blur adjustment for pixels located at the edge of the frame, the average value of the original gray levels of the pixels covered by the filter is calculated as the value after blur adjustment.

The above-mentioned embodiment is directed to the case where the second resolution is less than the first resolution. In addition, when the second resolution is equal to the first resolution, there is no need to reduce the resolution of the input signal of the second panel, but only need to further use a filter to adjust each pixel of the second panel The gray scale value is adjusted for blurring.

In summary, the present invention can effectively reduce the image quality degradation of text lines caused by inaccurate alignment or too large gap between the two panels by reducing the resolution of the second panel.

Although the present invention has been disclosed as above with examples, it is not intended to limit the present invention. Any person with ordinary knowledge in the technical field can make some changes and modifications without departing from the spirit and scope of the present invention. The scope of protection of the present invention shall be subject to the scope defined in the appended patent application.

F: Filter P: Adjusted pixels P1 to P4: Original pixels P ₀₀ to P ₄₇ : Pixels S105 to S115: Steps of the adjustment method of the display device with a double panel S205 to S225: Adjust the gray scale of each adjusted pixel Value method steps

FIG. 1 is a flowchart of an adjustment method of a display device with a dual panel according to an embodiment of the invention. FIG. 2 is a flowchart of a method for adjusting the grayscale value of each adjusted pixel according to an embodiment of the invention. FIG. 3 is a schematic diagram of the correspondence between the adjusted pixels and the original pixels according to an embodiment of the invention. FIG. 4 is a diagram for setting the grayscale value of the adjusted pixel with a value between the maximum value and the average value obtained in n original pixels according to an embodiment of the present invention. 5 is a schematic diagram of a filter according to an embodiment of the invention. 6A-6D are schematic diagrams of blurring adjustment using a filter according to an embodiment of the invention. 7 is a schematic diagram of a filter according to another embodiment of the invention.

S105~S115: Each step of the adjustment method of the display device with a double panel

Claims (4)

An adjustment method of a display device having a dual panel, wherein the display device includes a first panel and a second panel, the first panel is set to a first resolution, and the second panel is set to a second resolution, The adjustment method includes: when the display device receives an original signal, set the first panel with the original signal, and determine the input signal of the second panel through a lookup table, wherein the input signal is included in the first signal The grayscale value of the plurality of original pixels at the resolution; in the case where the second resolution is less than the first resolution, calculating the original pixels included in the second panel at the first resolution and the The correspondence between the adjusted pixels included in the second panel at the second resolution, and obtaining each of the adjusted pixels includes n original pixels, where n is an integer greater than or equal to 2; and Adjusting the grayscale value of each of the adjusted pixels between a maximum value and an average value obtained from the n original pixels corresponding to each of the adjusted pixels, including: based on each of the adjustments The n original pixels corresponding to the rear pixel calculate a bright-dark drop value; compare the bright-dark drop value with a first threshold value and a second threshold value, respectively, wherein the second threshold value is greater than the first threshold value Value; when the light-dark drop value is greater than the second threshold, the maximum value of the n original pixels is used as the grayscale value corresponding to the adjusted pixel; When the light-dark fall value is less than the first threshold, the average value of the n original pixels is used as the grayscale value corresponding to the adjusted pixel; and when the light-dark fall value is greater than or equal to the first threshold and When it is less than or equal to the second threshold, an interpolated value is used as the grayscale value corresponding to the adjusted pixel. The adjustment method for a display device with a dual panel as described in item 1 of the patent application scope, wherein the step of calculating the light and dark drop values based on n original pixels corresponding to each of the adjusted pixels includes: based on n The maximum value and a minimum value in the original pixels are used to calculate the difference between light and dark. The method for adjusting a display device having a dual panel as described in item 1 of the patent application scope, wherein after the step of adjusting the grayscale value of each of the adjusted pixels, the method further includes: using a filter to control the second panel The grayscale value of each of the adjusted pixels is adjusted for blurring, including: setting the filter, wherein the filter includes M×N block pixels, and the size of each block pixel corresponds to each of the block pixels The adjusted pixel size, and the M×N blocks have corresponding coefficients, and the M×N coefficients add up to 1; the center blocks of the pixels of the blocks of the filter are aligned one by one. The adjusted pixels; and after adding the gray-scale values of the adjusted pixels covered by the pixels of the blocks, based on the coefficients corresponding to the M×N blocks of the filter, blurring each of the adjusted pixels Pixel Grayscale value of. The method for adjusting a display device with a dual panel as described in item 1 of the scope of the patent application further includes: when the second resolution is equal to the first resolution, using a filter to input the second panel Each of the original pixels in the signal undergoes blurring adjustment, including: setting the filter, wherein the filter includes M×N block pixels, and the size of each block pixel corresponds to the size of each pixel , And the M×N blocks have corresponding coefficients, and the M×N coefficients add up to 1; the center block of the block pixels of the filter is aligned with each of the original pixels one by one And after adding the grayscale values of the original pixels covered by the pixels of the blocks, the grayscale values of each of the original pixels are blurred.

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