JP2805052B2 - How to display a color image on a liquid crystal display panel - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a method for displaying a color image on a liquid crystal display panel by a color video signal.

"Prior art" By a color video signal, a diagonal color filter is arranged for a portion that transmits red, green, and blue light with respect to a liquid crystal display element having a matrix matrix configuration. Conventionally, to display a color image on a liquid crystal display panel having a diagonal configuration for blue pixels, the red, green, and blue primary color video signals RV, GV obtained from an input color video signal as shown in FIG. , BV are sequentially shifted by a fixed time, sampled, A / D converted into digital data, and the obtained primary color video data RD,
GD and BD are alternately written to the two line memories for each line period of the input color video signal, and the input color video signals are respectively read from the two line memories in the next line period after the writing line period. In the case where display is performed alternately every one line period and display by interlacing (interlaced scanning) is performed, in an odd-numbered field of an input color video signal, as shown in FIG. First, the data RD1 drives the red pixel R at the intersection of the row L1 and the column K1, the data GD2 drives the green pixel G at the intersection of the row L1 and the column K2, and then the data BD3 drives the row L1 And drive the blue pixel B at the intersection of column K3 and then drive the red pixel R at the intersection of row L1 and column K4 with data RD4, and so on. In the next line period, the respective pixels in the row L3 are sequentially driven by the primary color video data read out during the next line period. , Etc. of the liquid crystal display panel 1 are sequentially driven, and in the even field of the input color video signal, in the first display line period, the data is read out in that line period. The respective pixels of the row L2 are sequentially driven by the primary color video data, and in the next line period, the respective pixels of the row L4 are sequentially driven by the primary color video data read in the line period,
Thus, the even rows L2, L4, L6 of the liquid crystal display panel 1
Are sequentially driven.

In the case of performing display by non-interlace (non-interlaced scanning), in the odd-numbered field and the even-numbered field of the input color video signal, in the line period to be displayed first, the readout is performed in that line period. Each pixel of the row L1 is sequentially driven by the primary color video data, and in the next line period, each pixel of the row L2 is sequentially driven by the primary color video data read in the line period, and so on. One row L1, L2,
L3 are sequentially driven.

Therefore, the number of rows N of the liquid crystal display panel 1 is equal to one of the input color video signals when displaying by interlacing.
The number of display lines in a frame (two fields) is made equal to the number of display lines in one field of an input color video signal when non-interlaced display is performed. The number of columns M of the liquid crystal display panel 1 is determined by the number of rows N and the aspect ratio of the display screen.

“Problem to be solved by the invention” However, in the above-described conventional display method,
The red, green, and blue color display dots R, G, and B of the liquid crystal display panel 1 are regarded as one color pixel, respectively, and the color display dots 1
The rows are driven by the primary color video data for one line period of the input color video signal, and the number of rows N of the liquid crystal display panel 1 is made equal to the number of display lines in one frame or one field of the input color video signal. As can be seen from the figure showing the case where the display screen is enlarged to twice the standard size in the vertical and horizontal directions, it is clear that the display screen can be enlarged by displaying the red, green and blue color display dots on the liquid crystal display panel. It is necessary to increase the size of R, G, B itself, therefore, when the display screen is enlarged, the resolution is deteriorated, and two or three adjacent color display dots R, G, B are driven, Even when mixed colors are to be displayed, there is a disadvantage that the color display capability and reproducibility are deteriorated such that the colors of the individual color display dots R, G, and B are conspicuous and the effect of the mixed colors is not sufficiently utilized.

Therefore, the present invention provides a method of displaying a color image on a liquid crystal display panel by using a color video signal, and standardizing the display screen without increasing the size of the red, green, and blue color display dots themselves of the liquid crystal display panel. The size of the display screen can be made larger than the size of the image to be displayed, and the display performance and reproducibility of colors can be improved even when the display screen is enlarged.

[Means for Solving the Problems] In the invention according to claim 1, a diagonal color filter is arranged for a portion transmitting red, green, and blue light with respect to a liquid crystal display element having a matrix matrix configuration. line,
This is a method of displaying an input color video signal in which one field has an N-line cycle on a liquid crystal display panel having a matrix of color display dots in mM columns (n and m are both positive integers of 2 or more). Red, green, and blue primary color video signals are obtained from an input color video signal, and the obtained primary color video signals are sampled at the same timing.
Perform M points per line, convert them to digital data, and convert these digital primary color video data to 2
To the line memories alternately for each line period of the input color video signal, and a total of nm colors extending over n adjacent rows in the row direction of the liquid crystal display panel and over m adjacent columns in the column direction. A color display dot group consisting of display dots is defined as one pixel, each row in the pixel matrix is sequentially associated with video data for each line cycle in each field of the input color video signal, and each column of the pixel matrix is The sample data of the above M points are sequentially associated,
The primary color video data at the same sampling point is read out from the unwritten line memory corresponding to each of the above colors, and one pixel corresponding to the sample point is read out of the red, green, and blue video data. The driving of the display dots of all the corresponding colors is performed for all the sample data in the line memory in which the writing is not performed during one line period.

[Operation] According to the display method of the first aspect of the present invention, the screen according to the value of n can be used without increasing the size of each of the red, green, and blue display dots of the liquid crystal display panel. The size can be increased.

And even if you increase the screen size like this, red,
The colors of the green and blue color display dots themselves are small, and a total of nm colors of each color display dot are arranged over n adjacent rows in the row direction of the liquid crystal display panel and over m adjacent columns in the column direction. The display dot group is one color pixel, and the color display dots of each color in the one color pixel are driven by the primary color video data of each color at the same sampling time, so two or three colors in one color pixel When the color display dots are driven, when the mixed colors are to be displayed, the color of each color pixel is inconspicuous, the color mixing effect is fully utilized, and a wide range of colors are faithfully displayed, and the color display ability And reproducibility is improved.

When n = m = 2 and the total number nm of the pixels of each color in one color pixel is not a multiple of 3, in one color pixel, a color display dot of one color has another color. Since one more or one less than the color display dot, one color pixel causes color imbalance and the color at the sample point is not displayed faithfully.
Among the three adjacent color pixels, one more or one less color display dot is different from each other, and the number of each color display dot becomes equal as a whole. Therefore, when looking at a set of three adjacent color pixels, Although there is some time lag, the color imbalance is compensated and the color at the sample point is displayed almost faithfully.

Embodiment As shown in FIG. 1, a liquid crystal display panel 10 used in the display method of the present invention is a liquid crystal display element having a matrix configuration.
11 is a matrix matrix configuration in which a diagonal color filter 12 is arranged for a portion transmitting red, green, and blue light, and a diagonal configuration is used for red, green, and blue color display dots R, G, and B. In the case of interlaced display, if the number of display lines in one frame (two fields) of the input color video signal CV is N on a standard size screen, the number of lines is n times as large as N in the present invention. nN. Here, n is a positive integer of 2 or more. The number of columns is determined by the number of rows and the aspect ratio of the display screen, and at the same time, is set to be m times the number of samples M in one line period of the input color video signal CV. Here, m is a positive integer equal to or less than n and greater than n / 2. That is, if the aspect ratio (horizontal / vertical) of the display screen is X / Y, To

The liquid crystal display panel 10 extends over n adjacent rows in the row direction, and extends over m adjacent columns in the column direction.
A color display dot group including a total of nm of blue color display dots R, G, and B is defined as one color pixel. Therefore, the liquid crystal display panel 10 used in the present invention is constituted by a total of nmNM color display dots of nN rows in the row direction and mM columns in the column direction, and as will be described later, Color pixels are red, green, blue color display dots R, G,
B, each having at least one color display dot
The number of R, G, and B are equal to each other, or the color display dot of one color is one more or one less than the color display dot of another color, and the color display dot of one color is another color Even if it is one more or one less than the color display dot of
Three adjacent color pixels differ from each other by one more or one less color display dot.

That is, when n = m = 2 as shown in FIG. 3, each of the color pixels C11, C12 and C13 extending over the rows L11 and L12 of the liquid crystal display panel 10 is representatively shown. Has two of one of the red, green, and blue color display dots R, G, and B, and has one each of the others, and, between three adjacent color pixels, one more pixel Are different from each other.

As shown in FIG. 1, the input color video signal CV obtained at the terminal 20 is a composite color video signal including a vertical synchronizing signal and a horizontal synchronizing signal, and the input color video signal CV is supplied to the video converter 30. The video converter 30 separates the red, green, and blue primary color video signals RV, GV, and BV from the vertical synchronization signal VS and the horizontal synchronization signal HS, and obtains the vertical synchronization signal VS and the horizontal synchronization signal HS. To obtain a timing control signal for controlling each unit from the timing control unit 40 as described later.

Primary color video signals RV, G of each color obtained from the video conversion unit 30
V and BV are supplied to the A / D converters 50R, 50G and 50B, respectively, so that the sampling points in one line period of the input color video signal CV are indicated by points T1, T2, T3... TM in FIG. A / D conversion to digital data by sampling at the same timing
Conversion, A / D conversion, and primary color video data RD, GD, BD of each color are obtained from the A / D converters 50R, 50G, 50B.

The primary color video data RD, GD, BD of each color obtained from the A / D converters 50R, 50G, 50B are respectively stored in two line memories 61R.
2, and 62R, 61G and 62G, 61B, and 62B are alternately written for each line period of the input color video signal CV, as shown in FIG.

Thus, the line memories 61R and 62R, 61G and 62G,
Primary color video data RD, G of each color written to 61B and 62B
As shown in FIG. 2, one line D of the input color video signal CV from the line memories 61R and 62R, 61G and 62G, 61B and 62B respectively in the next line period after the writing line period, as shown in FIG. The data is read alternately every period, and the read primary color video data of each color is supplied to a D / A conversion unit 80 through a multiplexer 70 to be D / A converted into a drive voltage AV, and the drive voltage AV is converted to a liquid crystal display panel 1.
In this case, the color display dots R, G, and B of each color in the one color pixel of the liquid crystal display panel 10 are driven by the primary color video data of each color at the same sampling time. And the primary colors of the respective colors from the line memories 61R and 62R, 61G and 62G, 61B and 62B so that n adjacent rows of the liquid crystal display panel 10 are driven by the primary color video data for one line period of the input color video signal CV. Reading of video data RD, GD, BD, switching of multiplexer 70, D / A conversion in D / A converter 80, and row driver 91 and column driver for liquid crystal display panel 10
The drive of the liquid crystal display panel 10 by 92 is controlled.

That is, in the case where n = m = 2 as shown in FIG. 3 and display by interlacing is performed, in the odd field of the input color video signal CV, the first half of the first displayed line period is displayed. In the period, LCD panel
According to the order of the arrangement of the respective pixels in the ten rows L11, as shown in the upper half of FIG. 4 as the first half period, the data RD1, at the sampling time T1 shown in FIG. GD1, data BD2, RD2 at sampling time T2, data GD3, B at sampling time T3
The primary color video data is read out in the order of D3..., First, the red color display dot R at the intersection of the row L11 and the column K11 of the color pixel C11 is driven by the data RD1, and then the row L11 of the color pixel C11 is driven by the data GD1. And the green color display dot G at the intersection of the column K12 and then the data BD2 drives the blue color display dot B at the intersection of the row L11 and the column K21 of the color pixel C12, and then the data RD2 C12
Of the color pixel C13 at the intersection of the row L11 and the column K31 of the color pixel C13, and then drive the data BD3 at the intersection of the row L11 and the column K22 of the color pixel C13. By driving the blue color element dots B at the intersection of the row L11 and the column K32 of the color pixel C13, and sequentially driving the respective color display dots of the row L11 of the liquid crystal display panel 10, the second half of the same line period In the period, according to the arrangement order of the respective color display dots in the row L12 of the liquid crystal display panel 10, as shown in the upper half of FIG. The primary color video data is read out in the order of the data GD1 and BD1 at the sampling time T1, the data RD2 and GD2 at the sampling time T2, and the data BD3 and RD3 at the sampling time T3. L1
Drive the green color display dot G at the intersection of 2 and column K11,
Next, the blue color display dot B at the intersection of the row L12 and the column K12 of the color pixel C11 is driven by the data BD1.
RD2 drives the red color display dot R at the intersection of the row L12 and column K21 of the color pixel C12, and the data GD2 drives the green color display dot G at the intersection of the row L12 and column K22 of the color pixel C12. Then, the data BD3 drives the blue color display dot B at the intersection of the row L12 and the column K31 of the color pixel C13, and the data RD3 then drives the red color display dot at the intersection of the row L12 and the column K32 of the color pixel C13. R, and so on, sequentially driving each color display dot of the row L12 of the liquid crystal display panel 10, and similarly in the first half of the next line period, each color display dot of the row L31 of the liquid crystal display panel 10 similarly. Are sequentially driven, and during the latter half of the same line period, the respective color display dots of the row L32 of the liquid crystal display panel 10 are similarly driven sequentially, and so on.
The ten rows L11, L12, L31, L32,... Are sequentially driven, and in the even field of the input color video signal CV, the liquid crystal display panel is similarly driven in the first half of the first displayed line period.
The respective color display dots of row L21 of 10 are sequentially driven, and the liquid crystal display panel 10 is similarly driven in the latter half of the same line period.
The respective color display dots of the row L22 are sequentially driven, and in the first half of the next line period, the respective color display dots of the row L41 of the liquid crystal display panel 10 are sequentially driven similarly, and the second half of the same line period In the same way, the row of LCD panel 10
The color display dots of L42 are sequentially driven, and the rows L21, L22, L41, L42,... Of the liquid crystal display panel 10 are sequentially driven.

In the case of performing non-interlaced display, the row L1 of the liquid crystal display panel 10 is also similarly used in the first half of the first displayed line period in both the odd field and the even field of the input color video signal CV.
1 are sequentially driven, and in the latter half of the same line period, the row L12 of the liquid crystal display panel 10 is similarly driven.
Are sequentially driven, and in the first half of the next line period, the respective color display dots are sequentially driven in the same manner in the row L21 of the liquid crystal display panel 10, and similarly in the second half of the same line period. The respective color display dots of the row L22 of the liquid crystal display panel 10 are sequentially driven, and so on, and the rows L11, L12, L21, L22, L31, L32, L41, L42 of the liquid crystal display panel 10, and so on.
Are sequentially driven.

When n = m = 2 in this way, as is apparent from FIG. 3, the red, green, and blue pixels R,
The size of G and B itself is the same as that of the liquid crystal display panel shown in the upper part of FIG. 13 in the conventional display method, that is, 1/4 of that of the liquid crystal display panel shown in the lower part of FIG. The conventional display method is four times as large as that of the standard size liquid crystal display panel shown in the upper part of FIG.
That is, the size can be increased as in the case of the liquid crystal display panel shown in the lower part of FIG.

And even if the display screen is enlarged like this, red, green,
The size of the blue color display dots R, G, and B themselves is small, and the color display dots extending over the adjacent two rows and two columns are treated as one color pixel as described above.
, The color display dots R, G, and B are inconspicuous when the color display dots of two or three colors in one color pixel are to be driven by driving the color display dots. The color display ability and reproducibility are improved, for example, a wide range of colors can be faithfully displayed by making full use of the effect.

However, in this case, as apparent from the color pixels C11, C12, and C13 shown in FIG. 3 or FIG. 4, each color pixel has one of the red, green, and blue color display dots R, G, and B. Since it has two ones and only one each of the others, when looking at one color pixel, color imbalance occurs and the color at the sample point is not displayed faithfully,
The three color pixels adjacent to each other have different color display dots by one, and the color display dots R, G,
Since the number of B becomes equal, as for the set of three adjacent color pixels, although there is a slight time lag, the color imbalance is compensated and the color at the sample point is displayed almost faithfully .

In this case, the number of samples M in one line period of the input color video signal CV is, as apparent from the equation (3), To

FIG. 5 shows a configuration example of color play when n = m = 3, and FIG. 6 shows a configuration example of color pixels when n = 3, m = 2.

When n = 3, the liquid crystal display panel 10
The display screen can be enlarged nine times without changing the size of the red, green, and blue color display dots R, G, and B themselves, and the color display capability is the same as when n = m = 2. And reproducibility is improved. However, in this case, as is clear from FIGS. 5 and 6, since the number of red, green, and blue color display dots R, G, and B is equal to each other, n = m = In the case of setting 2, the above-mentioned problem of color imbalance does not occur.

Note that, in this case, the number of samples M in one line period of the input color video signal CV is the number represented by the equation (4) when n = m = 3, as in the case where n = m = 2. When n = 3 and m = 2, the number is set to 1.5 times the number represented by the equation (4) as is apparent from the equation (3).

n may be 4 or more. FIG. 7 shows a case where n = m = 4, FIG. 8 shows a case where n = 4, m = 3, FIG. 9 shows a case where n = m = 5, and FIG. FIG. 11 shows an example of the configuration of a color pixel when n = 5 and m = 3 when 5, m = 4.

Since the number of samples M in one line period of the input color video signal CV is expressed by the equation (3), when n / m is made smaller than 1, the number of samples M is expressed by the equation (4). When the number of samples becomes much smaller than 1, the number of samples M becomes considerably larger than the number expressed by the equation (4), and the circuit load is reduced. However, in the present invention, as described above, by making m a positive integer less than or equal to n and greater than n / 2, n / m is a number greater than or equal to 1 and less than 2.
The horizontal resolution does not decrease, and the circuit load does not increase.

It goes without saying that the color image according to the present invention is not limited to an image in a narrow sense, but includes characters, figures, graphs, and the like.

[Effects of the Invention] As described above, according to the present invention, a color display dot group including a total of nm color display dots of each color, which spans the adjacent n rows and m columns of the liquid crystal display panel, is defined as one color pixel. The color display dots of each color in the one color pixel are driven by the primary color video data of each color at the same sampling time, and the adjacent n rows of the liquid crystal display panel are driven by the primary color video for one line period of the input color video signal. Since the display is driven by data, the display screen can be enlarged according to the value of n without increasing the size of the color display dots of each color of the liquid crystal display panel, and even when the display screen is enlarged, the color display is performed. The ability and reproducibility become good.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a display method according to the present invention;
FIG. 2 is a diagram showing a mode of writing primary color video data to a line memory and reading it from a line memory. FIG. 3 is a diagram showing a sampling mode of a primary color video signal and a liquid crystal display when n = m = 2. FIG. 4 is a diagram showing the configuration of a panel and color pixels, and FIG. 4 is a diagram showing a mode of reading primary color video data and driving a liquid crystal display panel when n = m = 2, FIG. FIGS. 7, 8, 9, 10, and 11 each show an example of the configuration of a color pixel when n ≧ 3, and FIG. 12 shows a primary color image in a conventional display method. FIG. 13 is a diagram showing a signal sampling mode and a configuration of a liquid crystal display panel. FIG. 13 is a diagram for explaining a case where a display screen is enlarged in a conventional display method.

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Claims (1)

(57) [Claims] 1. A matrix of color display dots of nN rows and mM columns is provided by arranging a color filter of a diagonal configuration for a portion that transmits red, green, and blue light with respect to a liquid crystal display element of a matrix matrix configuration. A method of displaying an input color video signal in which one field has an N-line cycle (n and m are both positive integers of 2 or more) on the liquid crystal display panel, wherein red, green, and blue are obtained from the input color video signal. These primary color video signals are sampled at the same timing, the sampling is performed at M points per line, and converted into digital data. Each of these digital primary color video data is In the line memory of the input color video signal alternately every one line period, and straddling the adjacent n rows in the row direction of the liquid crystal display panel, A color display dot group consisting of a total of nm color display dots spanning m columns adjacent to each other in one direction is defined as one pixel, and each row in the matrix of pixels is an image for each line cycle in each field of the input color video signal. The data is sequentially associated with each column of the pixel matrix, and the sample data at the M points are sequentially associated with each other. During the one-line period, the reading of the data and the driving of the display dots of all the corresponding colors in one pixel corresponding to the sample point with the red, green, and blue video data are performed during one line period. A method of displaying a color image on a liquid crystal display panel, wherein the method is performed for all sample data in a line memory that has not been performed.