JP2002169515A - Color image display - Google Patents

Abstract

(57) [Summary] [PROBLEMS] A color image display device of a frame sequential method,
Suppresses color breakup, blurred image outlines, judder interference, etc.
Provided is a color image display device having improved moving image display performance. SOLUTION: A mixed color component is displayed without being temporally separated,
In a black-and-white image, color breakage is completely prevented, and in a color image, high-luminance color breakage that occurs in a color image close to a mixture of two of the three primary colors or a white image is reduced. . Further, in the hold-type display method, at least one non-display field is provided between frames to approximate an impulse-type display method having a relatively long non-display period in a frame, thereby improving moving image display performance. .

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a color image display apparatus of a frame sequential type for sequentially displaying different colors for each field within one frame to perform color display.

[0002]

2. Description of the Related Art In color image display, a method of expressing a large number of colors by mixing primary colors of light is used. Among the widely used color mixing methods, there are simultaneous additive color mixing and successive additive color mixing.

[0003] Simultaneous additive color mixture is a method of expressing color mixture by superimposing a plurality of primary color lights at the same time.
2. Description of the Related Art A method of lighting a plurality of primary color lights in a small area (usually one pixel) having a spatial resolution equal to or smaller than the eye is often used in televisions and the like.

[0004] Successive additive color mixing is a method that uses afterimages of the retina to express color mixing by illuminating a plurality of primary color lights in a short period of time less than the temporal resolution of the eyes.

[0005] Successive additive color mixing has the advantage that it is easy to obtain high resolution because it is not necessary to provide a plurality of different primary color light lighting areas in one pixel as is often used in simultaneous additive color mixing. .

[0006] A display method utilizing successive additive color mixing includes a screen sequential method or an image sequential method (Field Sequentialia).
l) There is a display method called a method, which is mainly a monochrome C
RT (cathode ray tube) and liquid crystal shutter optical system (USP47
58818 or US Pat. No. 4,611,889) and a color light source system combining a monochrome LCD (liquid crystal display) and three primary color light sources.

With reference to FIG. 7, the operation of a conventional example of a plane-sequential type liquid crystal color image display device using a color light source system combining this monochrome LCD and three primary color light sources will be described.

A color image signal is supplied from an input terminal 11 to R
A (red) image signal, a G (green) image signal from the input terminal 12, and a B (blue) image signal from the input terminal 13 are input as analog signals, respectively, and an A / D converter (analog / digital converter) At 51, 52, and 53, digital conversion processing is performed.

The RGB image signals digitally output from the A / D converters 51, 52 and 53 and the Sync (synchronous signal) input from the input terminal 14 are converted into P / S converters (parallel / serial converters). 54. The P / S converter 54 saves each of the RGB image signals in the memory 55 once, subjects the RGB image signals to triple speed processing, and outputs them as serial signals. The triple speed serial RGB image signal is supplied to the liquid crystal panel 58.

The RGB image signals supplied to the liquid crystal panel 58 are converted into analog signals by a drive IC (integrated circuit) (not shown) and used for display. Also, the sync branched from the P / S converter 54 is supplied to the liquid crystal panel 58 and the backlight light source 59.

The liquid crystal panel 58 displays a monochrome image based on the supplied RGB image signals. Further, the backlight light source 59 turns on each of the RGB light sources based on the supplied Sync timing as shown in FIG. That is, the R light source is turned on when the R image is displayed on the liquid crystal panel 58, and the G light source is displayed when the G image is displayed.
The light source is turned on, and the B light source is turned on when the B image is displayed.

In this manner, by sequentially displaying the RGB images by the above processing, a full-color image can be displayed by successive additive color mixing.

[0013]

In the above-described color image display of the frame sequential method, no problem occurs when a still image is displayed and the line of sight of the observer does not move. When displaying a moving image in which the represented image moves on the screen, or when the observer's line of sight moves on the screen on which such an image is projected, the time difference between the display of each of the RGB fields. R included in the color mixture
A color breakup phenomenon occurs in which GB elements are separated and displayed on the edge of the image.

The mechanism of color breakup when a white image, which can be obtained by combining RGB when the background color is black, moves from left to right on the screen will be described with reference to FIG.

As shown in FIG. 9 (a), assuming that the observer moves the line of sight to the center position of the G field display following the white image as the position of the white image moves, Line s indicating the trajectory of the line of sight
Is different from the G field display in the R field display and the B field display. As a result, the positions of the afterimages on the retina in the RGB field displays are shifted, and as shown in FIG. Occurs.

For the same reason, a similar phenomenon occurs when the line of sight is suddenly moved from outside the screen to inside the screen.

[0017] These phenomena are called color breakup,
The color breaks that occur in achromatic images are more noticeable.

As means for preventing such color breakage,
A method of extracting a W (white) component to make one frame by RGBW, a method of changing the field order of each color of RGB, and the like are disclosed.

However, even if the method of extracting the W component and forming one frame with four fields of RGBW is used, for example, as shown in FIG. 10A, when the yellow image moves from left to right, Also, as shown in FIG. 10B, green coloring occurs on the left side of the yellow image.
Red coloring may occur on the right side.
In this case, the W field and the B field are not lit.

Further, even if the field order of each color of RGB is changed, coloring occurs in the same manner, and none of these prevention means has been able to completely suppress color breakup.

Further, in a liquid crystal color image display device and the like which have been widely used in recent years, there is still a problem in display quality of moving images.

In a liquid crystal color image display device, when a certain pixel emits light (becomes in an open state), as shown in FIG. 11A, the display maintains a substantially constant brightness until the next field is written. . Such a display method is called a hold type. On the other hand, in a CRT display or the like, a temporal change in light emission becomes instantaneously high luminance.
That is, as shown in FIG. 11B, the light emission state of a certain pixel emits light for one moment in one field (the light emission time depends on the characteristics and resolution of the CRT). Such a display method is called an impulse type.

In the above impulse type, when changing from an image of a certain n (n is an integer) frame to an (n + 1) th frame,
There is a sufficient non-display period before and after the light emission of each frame, and an afterimage of light emission of the immediately preceding frame does not remain on the retina, so that a smooth moving image display can be obtained.

However, in a display method such as a hold type having a relatively long light emission time, an image of a certain n frame is displayed just before changing to an (n + 1) th frame.
This causes blurring of the image outline and judder disturbance (a phenomenon in which the movement of the image is jerky and looks unnatural).

SUMMARY OF THE INVENTION The present invention has been made in view of the above-described problems, and in a color image display apparatus of a frame sequential method, color breakage, blurring of image outlines, judder disturbance, and the like are suppressed, and moving image display performance is improved. It is an object of the present invention to provide a color image display device.

[0026]

According to a first aspect of the present invention, there is provided an image processing apparatus comprising: a first primary color; a second primary color;
An input color image signal input as a monochromatic image signal of three primary colors consisting of a third primary color is obtained by combining the three primary colors, a first mixed color that is a mixed color of the first primary color and the second primary color, and a second color image signal.
A second mixed color that is a mixed color of a primary color and the third primary color, a third mixed color that is a mixed color of the third primary color and the first primary color, and white; Image signal separating means for separating into separated image signals that are at least five single-color image signals including white, and a single-color image of a color represented by each of the signals included in the separated image signal can be displayed by simultaneous additive color mixing And a driving means for driving the monochromatic image display means based on the separated image signal.

According to such a configuration, in the color image, the three primary color components and the three primary color mixed components are all separated and displayed at one time, so that the mixed color components are not separated temporally. Can be displayed. For this reason, color breakup is completely prevented in black-and-white images, and high brightness is also achieved in color images.
It is possible to reduce visible color breaks that occur in an image of a color close to a mixture of two of the three primary colors or a white image.

According to a second aspect of the present invention, in the electrophoretic display device according to the first aspect, the image signal separating means subtracts a white component from the input color image signal to generate a first subtraction result signal. By generating, the input color image signal is separated into a white image signal and a first subtraction result signal, and from the first subtraction result signal, the first color mixture,
The first subtraction result signal is subjected to a second subtraction by generating a second subtraction result signal by subtracting a component of a second subtraction color that is one of the second color mixture and the third color mixture. A color image signal and a second subtraction result signal, and from the second subtraction result signal, the second subtraction of any one of the first mixed color, the second mixed color, and the third mixed color The second subtraction result signal is separated into a third subtraction color image signal and a third subtraction result signal by generating a third subtraction result signal by subtracting a third subtraction color component other than the color. Then, the first color mixture, the second color mixture, the third color mixture,
A fourth subtraction result signal is generated by subtracting a component of a fourth subtraction color that is any one of the mixed colors and is a remaining color other than the second subtraction color and the third subtraction color, The third subtraction result signal is separated into a fourth subtraction color image signal and a fourth subtraction result signal, and the input color image signal is divided into a white image signal, a second subtraction color image signal, and a third subtraction color image. In a preferred embodiment, the image signal is separated into seven single-color image signals including a signal, a fourth subtraction color image signal, and a fourth subtraction result signal that is the three primary color image signals.

The invention described in claim 3 is the invention according to claim 1 or 2
In the electrophoretic display device according to the above, the single-color image display means, transmission-type monochrome image display means, and each of the signals included in the separated image signal in synchronization with the display of the monochrome image display means represents A backlight light source capable of lighting colors by simultaneous additive color mixing,
Is included as a preferred embodiment.

According to a fourth aspect of the present invention, in the electrophoretic display device according to the third aspect, the monochrome image display means is preferably a liquid crystal panel.

[0031] The invention according to claim 5 is the invention according to claims 1 to 4.
5. The electrophoretic display device according to claim 1, wherein the driving unit outputs the single-color image signal included in the separated image signal to the single-color image display unit as a serial signal in an arbitrary order. Is included as a preferred embodiment.

According to a sixth aspect of the present invention, in the electrophoretic display device according to the fifth aspect, the driving unit transmits the single-color image signal included in the separated image signal to the single-color image display unit using a serial signal. The output order of the serial signals is to compare the luminance information of each input color image signal, and to output the signal with higher luminance positioned at the temporal center in one frame.
Is included as a preferred embodiment.

According to such a configuration, even in a color image display device using a hold-type display method such as a liquid crystal color image display device, at least one non-display field always enters between frames. ,
This is similar to an impulse-type display method having a relatively long non-display period in a frame, and the moving image display performance can be improved.

[0034] The invention according to claim 7 is the invention according to claims 1 to 6.
5. The electrophoretic display device according to claim 1, wherein the three primary colors include red, green, and blue as a preferred embodiment.

[0035]

FIG. 1 is a block diagram showing an embodiment of a color image display device according to the present invention. 1
Is an image signal separating means, 2 is a monochrome image display means, 3 is a driving means, 4 is an input color image signal, 5 is a separated image signal, 6
Represents a serial signal. Sync represents a synchronization signal.

The image signal separating means 1, which is one of the features of the present invention, converts an input color image signal 4 inputted as a three primary color single color image signal into a mixture of three primary colors, and a first primary color and a second primary color. , A second mixed color that is a mixed color of the second primary color and the third primary color, a third mixed color that is a mixed color of the third primary color and the first primary color, and white. , A separation image signal which is a single-color image signal of at least five colors including the three primary colors and white.

The three primary colors are generally RGB (red,
Green and blue) are widely used, but the present invention is not limited thereto. All colors used for color display are expressed by a combination of three colors, RGB
Is only one of them. In the present invention, the three colors of the combination required for color display
Primary colors. For example, the first primary color is red, the second primary color is
When the primary color is green and the third primary color is blue, the first color mixture is yellow, the second color mixture is cyan, and the third color mixture is blue.

An example of a method for separating a color image signal according to the present invention will be described with reference to FIG. When a certain RGB signal is input, the original signal is subtracted from the original signal by subtracting a white component signal included in the signal as shown in FIG. And a white component signal. This signal is
As a mixed color component other than white, a yellow component as shown in FIG. 2B is included. Therefore, by subtracting the yellow component, the color image signal can be finally separated into a white component signal, a yellow component signal, and a remaining green component signal.

The single-color image display means 2 is an image display means capable of displaying a single-color image of a color represented by each of the signals included in the separated image signal by simultaneous additive color mixing.

As described above, by separating the signals of the mixed color components and displaying each of the signals included in the separated image signal by using the image display means capable of displaying the single color image by simultaneous additive color mixing, Can be displayed without being temporally separated. For this reason, color breakup is completely prevented in a black-and-white image, and also in a color image, a high-luminance image is generated in an image of a color that is close to a mixture of two colors of white and three primary colors.
Color breaks that are easily visible can be reduced.

The driving means 3 is means for driving the monochromatic image display means 2 based on the separated image signal 5. In the driving means 3, the monochrome image signal included in the separated image signal 5 is
It is preferable to use a widely used method of outputting a serial signal to the monochrome image display means 2.

In the present invention, it is preferable that the separated image signal 5 and the serial signal 6 include all the color information of the seven colors, but include at least three primary colors and white.
All that is required is the color information of the color.

When the signals 5 and 6 include only a single color image signal of five or six colors, the color of the fifth or sixth color is obtained by subtracting the white component from the original color image signal into the first signal. When a mixed color component other than white, such as a mixed color, a second mixed color, or a third mixed color, is included, the color must be included. Therefore, it is preferable that the signals 5 and 6 include all the signals of the seven colors so that it is not necessary to discriminate the signals one by one.

Further, the output order in which the separated image signal 5 is output as a serial signal is such that the luminance information of each input color image signal is compared, and the higher luminance signal is temporally positioned in one frame within one frame. It is preferable to output.

If the signals 5 and 6 include at least five single-color image signals, as will be described later in detail, signals other than the three signals of the mixed color components such as white and yellow and any one of RGB are used. At least two signals may be a signal of luminance 0.

Therefore, by changing the output order to the above-mentioned predetermined order, at least one non-display field is always inserted between frames, so that a hold type display such as a liquid crystal color image display device is used. Also in a color image display device using the method, it is close to an impulse type display method having a relatively long non-display period in a frame, and the moving image display performance can be improved.

Hereinafter, specific embodiments of the present invention will be described with reference to the drawings, but the present invention is not limited thereto.

(Embodiment 1) FIG. 3 shows a three-primary-color single-color image signal input as a three-primary-color single-color image signal in a frame sequential color liquid crystal display device according to one embodiment of the present invention. FIG. 2 is a block diagram showing a process from obtaining an image signal + 4 mixed color image signal to reaching full color display.

As an input color image signal, an R image signal is input from an input terminal 21, a G image signal is input from an input terminal 22, and a B image signal is input as an analog signal from an input terminal 23. Then, the RGB image signal is converted by the A / D converter 6
At 1, 62 and 63, digital conversion processing is performed.

The RGB image signals output from the A / D converters 61, 62 and 63 and the synchronization signal Sync input from the input terminal 24 are supplied to a minimum luminance detection circuit 64 and a P / S converter 65.

The minimum luminance detection circuit 64 recognizes the start of one frame based on the input synchronization signal Sync, and resets a counter in the circuit.

For example, the in-circuit counter is set to 1 by the RGB image signal input after the reset. Then, the respective signals included in the input RGB image signals are compared, a signal having the minimum luminance is detected, a W (white) image signal having the minimum luminance is generated, and an input signal of the P / S converter 65 is input. The signal is supplied to the terminal 30 and the input terminal 25 of the subtraction circuit 66, and the inputted RGB image signal is further supplied to the subtraction circuit 66.

The subtraction circuit 66 subtracts the W image signal from the input RGB image signal to generate a first subtraction result signal. The signals included in the first subtraction result signal are output from the minimum luminance detection circuit 64, respectively. Input terminals 21, 22, 23
Feedback. That is, the RGB image signal (color image signal not including the W component) subjected to the subtraction process once is input to the minimum luminance detection circuit 64.

According to the first subtraction result signal which is fed back from the subtraction circuit 66 and input from the input terminals 21, 22, 23 of the minimum luminance detection circuit 64, the count number of the in-circuit counter becomes, for example, two. Then, based on the count number, two signals among the signals included in the first subtraction result signal, for example, a signal having the minimum luminance among the R image signal and the G image signal are detected, and Y (yellow) having the minimum luminance is detected. , R and G), and supplies the image signal to the input terminal 31 of the P / S converter 65 and the input terminal 26 of the subtraction circuit 66, and further supplies the first subtraction result signal to the subtraction circuit 66.

In the subtraction circuit 66, from the first subtraction result signal,
A subtraction process is performed on the Y image signal to generate a second subtraction result signal. The signals included in the second subtraction result signal are fed back to the input terminals 21, 22, and 23 of the minimum luminance detection circuit 64, respectively. That is, the RG subjected to the subtraction process twice
The B image signal (color image signal not including the W component and the Y component) is input to the minimum luminance detection circuit 64.

According to the second subtraction result signal fed back from the subtraction circuit 66 and input from the input terminals 21, 22, and 23 of the minimum luminance detection circuit 64, the count number of the in-circuit counter becomes, for example, three. Then, based on the count number, two signals among the signals included in the second subtraction result signal, for example, a signal of the minimum luminance among the G image signal and the B image signal are detected, and C (cyan) having the minimum luminance is detected. , G and B
An image signal is generated and supplied to the input terminal 32 of the P / S converter 65 and the input terminal 27 of the subtraction circuit 66, and further the second subtraction result signal is supplied to the subtraction circuit 66.

In the subtraction circuit 66, from the second subtraction result signal,
A subtraction process is performed on the C image signal to generate a third subtraction result signal. The signals included in the third subtraction result signal are fed back to the input terminals 21, 22, and 23 of the minimum luminance detection circuit 64, respectively. That is, the RG subjected to the subtraction process three times
The B image signal (color image signal not including the W component, the Y component, and the C component) is input to the minimum luminance detection circuit 64.

The count value of the in-circuit counter becomes, for example, 4 by the third subtraction result signal which is fed back from the subtraction circuit 66 and input from the input terminals 21, 22, and 23 of the minimum luminance detection circuit 64. Then, based on the count number, two signals among the signals included in the third subtraction result signal, for example, a signal having the minimum luminance among the B image signal and the R image signal are detected, and M (magenta, B and R
An image signal is generated and supplied to the input terminal 33 of the P / S converter 65 and the input terminal 28 of the subtraction circuit 66, and the third subtraction result signal is supplied to the subtraction circuit 66.

In the subtraction circuit 66, from the third subtraction result signal,
A subtraction process is performed on the M image signal to generate a fourth subtraction result signal, and the input terminals 21, 22, and 23 of the minimum luminance detection circuit 64 are generated.
Give feedback. That is, the RGB image signals (color image signals not including the W component, the Y component, the C component, and the M component) subjected to the four-time subtraction processing are input to the minimum luminance detection circuit 64.

The input terminals 21 and 2 of the minimum luminance detection circuit 64
According to the fourth subtraction result signal input from 2, 23, the count number of the in-circuit counter becomes, for example, 5. At this time, the fourth subtraction result signal is not processed, and the RGB image signals included in the fourth subtraction result signal are supplied to the input terminals 34, 35, and 36 of the P / S converter 65, respectively.

The image signal input in parallel from the input terminals 30 to 36 of the P / S converter 65 is output as a serial signal via the memory 67. That is, R, G, B,
A 7 × speed signal obtained by time division multiplexing the W, Y, C, M signals is
It is supplied to the liquid crystal panel 68. Further, the synchronization signal Sync supplied from the input terminal 38 is synchronously separated and input to the liquid crystal panel 68 and the backlight light source 69, respectively.

In the liquid crystal panel 68, the input 7 × -speed digital signal is converted into an analog signal by a driver IC (not shown), and a monochrome image is displayed according to the timing of the synchronization signal Sync. That is, images of the respective R, G, B, W, Y, C, and M fields separated in one frame are sequentially displayed.

The backlight light source 69 turns on the backlight light source according to the input synchronization signal Sync. FIG. 4 shows a driving waveform of each color light source and a color of each field obtained by simultaneous additive color mixing as a result of driving when the backlight light source has light sources of three primary colors of RGB. BL is an abbreviation for backlight.

When the light sources of the three primary colors are individually turned on, the R, G, and B fields are provided. In addition, a W field can be obtained by simultaneously turning on the R, G, and B light sources. Similarly, the Y field can be obtained by turning on the R and G light sources simultaneously, and the C field can be obtained by turning on the G and B light sources simultaneously, and the R and B light sources are turned on simultaneously. Thus, M fields can be obtained.

In this way, the monochrome images of the R, G, B, W, Y, C, and M fields separated within one frame are sequentially displayed on the liquid crystal panel 68, and the backlight light source 69 synchronously displays the monochrome images of the R, G, B, W, Y, C, and M fields. , G, B, W, Y, C, M
Is turned on by simultaneous additive color mixture, a color image can be displayed.

In order to realize image separation by the above-described processing, the image signal separating means of the present invention uses the minimum luminance signal among the signals contained in the input three primary color image signals. And a mixed-color image signal that is a single-color image signal having the minimum luminance of two or more mixed colors including a color represented by the signal having the minimum luminance among the three primary colors. Color mixing signal generating means,
It is preferable that the image processing apparatus further includes a subtraction processing unit that subtracts the mixed color image signal from the at least three single color image signals.

The liquid crystal panel includes, for example, an OCB type, TN
(Twisted nematic) type, STN (super twisted nematic) type, FLC (ferroelectric liquid crystal) type and the like can be used.

As the backlight light source, for example, a cold cathode tube, a light source in which RGB LEDs (light emitting diodes) are appropriately arranged, a light source in which white light is combined with a variable color filter, and the like can be used.

Further, the single-color image display device of the present invention can simultaneously display the color represented by each of the signals included in the separated image signal in synchronism with the display of the reflection type monochrome image display means and the monochrome image display means. And a backlight light source capable of lighting in color by additive color mixture. As the reflection type monochrome image display means, for example, "DMD (digital micromirror device)" manufactured by Texas Instruments can be used.

(Embodiment 2) In the present embodiment, in the apparatus as described in Embodiment 1, the output order in which the separated image signal is output as a serial signal from the P / S converter is input. A description will be given of a mode in which the luminance information of each color image signal is compared, and the higher luminance signal is temporally positioned at the center in one frame and output.

For example, even if image information having luminance information in any of the three primary color information is input, the first embodiment
When the signal separation processing described in (1) is performed, first, any one of the three primary colors does not have luminance information in white component extraction. That is, the signal has a luminance of 0. Subsequently, by extracting the yellow, cyan, and magenta components, only one of the three primary colors has nonzero luminance information. In addition, any two of the three primary color information
If the extraction of yellow, cyan, and magenta components, which can be obtained with the minimum luminance of a color, is also performed after the white components have been completely extracted, it is unlikely that two components exist simultaneously in one frame.

That is, the lighting in the seven fields is as follows.
A maximum of three of white, one of yellow, cyan, and magenta, and one of three primary colors
Can be a field.

Therefore, it is possible to provide a blank period between the images of each frame by changing the order of the fields so that the lighting field is located at the center in time, and it is possible to provide a hold type which is frequently used in a liquid crystal panel. Even if the display method of (1) is used, it is possible to display a sharp moving image such as an impulse type.

FIG. 5 is a diagram showing a lighting state of an n frame and an (n + 1) frame of a certain pixel. FIG. 5 (a)
Luminance information of R = 30%, G = 70%, B = 40% is input to n frames, and 10 RGB each are input to n + 1 frame.
It shows the lighting state of the light source in the conventional RGB system when 0% luminance information is input. FIG. 5B shows a three-primary-color single-color image signal +4 of the present invention when the same luminance information is input.
FIG. 4 is a diagram showing a lighting state of a light source when RGB is used as three primary colors in a mixed color image signal method.

For example, if a certain pixel in n frames has R = 30
%, G = 70%, and B = 40%, when the three primary color signals are input, the conventional RGB method does not have a pause period between +1 frame as shown in FIG. 5A. ,
It is recognized as a remaining image of the previous frame image.

On the other hand, in the case of the method of the present invention, as shown in FIG.
When three primary color signals of G = 70% and B = 40% are input, if the signal separation processing described in the first embodiment is performed, W = 30%, C = 10%, and G = 30. % Luminance information is generated, and the lighting time in one frame is 3/7. Next, when luminance information of 100% for each of RGB is input to the (n + 1) th frame, if color mixture generation is performed in descending order of luminance, W = 100%, and the lighting time in one frame becomes 1/7.

When such a color image signal is serially output from the P / S converter 65, by using the P / S converter 65 and the memory 67, R, G, C, and W can be centered on the high luminance field. , Y, M, and B in order to display moving images, it is possible to have 6/7 black fields from the lighting of the nth frame to the lighting of the (n + 1) th frame. Therefore, it becomes possible to light up the (n + 1) th frame in a state where the afterglow of the nth frame is almost canceled from the retina.

However, for example, three primary color signals of R = 50%, G = 30%, and B = 60% are input to a certain pixel of n frames, and R = 80%, G to a certain pixel of n + 1 frame.
= 60%, B = 20% when three primary color signals are input,
In the nth frame, the W, M, and B fields are turned on, and n
In the +1 frame, the R, W, and Y fields are turned on, and in the field order described above, no black period can be provided between the frames, resulting in a poorly sharp moving image display.

Therefore, R, once stored in the memory 67,
The luminances of the G, B, W, Y, C, and M fields are compared, and the field order is changed so that the higher luminance field is temporally located in the center of the frame.
The S converter 65 outputs a serial signal and a synchronization signal Sync.

In synchronization with this, the P / S converter 65 outputs a light source lighting timing signal and a synchronization signal Sync to the backlight light source 69.

The liquid crystal panel 68 displays a monochrome image in accordance with the serially input signal of each field and the timing of the synchronization signal Sync. The backlight light source 69 displays the input light source lighting timing signal and the synchronization signal Sy.
In accordance with the timing of nc, the three primary colors + 4 mixed colors are turned on. As a result, the lighting positions of the respective fields are gathered at the center within each frame time, and a display characteristic close to an impulse type having a non-display period is obtained, so that a sharp moving image can be displayed.

[0082]

As described above, according to the present invention, in a color image, the three primary color components and the three primary color components are all separated and displayed at one time. Can be displayed without separation. For this reason, color breakup is completely prevented in a black-and-white image, and also in a color image, a high-luminance, easily-visible color breakup that occurs in a color image close to a mixture of two of the three primary colors or a white image. Can be reduced.

Also, in a color image display device using a hold type display method such as a liquid crystal color image display device, at least one non-display field is always included between frames, so that a relatively small number of non-display fields are present in a frame. This is closer to an impulse-type display method having a long non-display period, so that moving image display performance can be improved.

As described above, in the color image display device of the frame sequential system, it is possible to provide a color image display device in which color breakage, blurring of image outlines, judder disturbance, and the like are suppressed and moving image display performance is improved. .

[Brief description of the drawings]

FIG. 1 is a block diagram showing an embodiment of a color image display device according to the present invention.

FIG. 2 shows an example of a color image signal separation method according to the present invention.

FIG. 3 is a block diagram showing a specific configuration of an embodiment of a color image display device according to the present invention.

FIG. 4 shows the lighting timing and display color of each backlight in one frame of the color image display device according to the embodiment of the present invention.

FIG. 5 is a diagram showing a comparison of light source lighting timings between a three-primary-color single-color image signal + four-mixed-color image signal system according to the present invention and an RGB system which is one of conventional examples.

FIG. 6 shows a light source lighting timing of one embodiment of a three-primary-color single-color image signal + four-mixed-color image signal system according to the present invention.

FIG. 7 is an example of a block diagram of a color image display device in one conventional RGB plane sequential system.

FIG. 8 shows a light source lighting timing and a display color in one frame of a color image display device of one conventional RGB plane sequential system.

FIG. 9 is a conceptual diagram showing color breakage of a color image display device in one conventional RGB plane sequential system.

FIG. 10 is a conceptual diagram showing color breakage of a color image display device in one conventional RGB + W screen sequential system.

FIG. 11 is a comparison diagram of a light source lighting timing between an impulse type and a hold type.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Image signal separation means 2 Single color image display means 3 Driving means 4 Input color image signal 5 Separation image signal 6 Serial signal 21, 22, 23, 24 Input terminal 51, 52, 53, 61, 62, 63 A / D converter 58, 68 Liquid crystal panel 59, 69 Back light source 54, 65 P / S converter 55, 67 Memory 64 Minimum luminance detection circuit 66 Subtraction circuit

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Seishi Miura 3-30-2 Shimomaruko, Ota-ku, Tokyo F-term in Canon Inc. (reference) 5C006 AA22 AF44 BB11 BF02 EA01 5C066 AA03 CA05 DC06 GA01 KM10 KM13 5C080 AA10 BB05 CC03 DD01 EE19 EE29 EE30 JJ02 JJ04 JJ05

Claims (7)

[Claims] 1. An input color image signal input as a three-primary-color single-color image signal consisting of a first primary color, a second primary color, and a third primary color is converted into the three primary colors, the first primary color, and the second primary color.
A first mixed color that is a mixed color with a primary color, a second mixed color that is a mixed color of the second primary color and the third primary color, a third mixed color that is a mixed color of the third primary color and the first primary color, and white. And 7
Image signal separating means for separating into at least five single-color image signals including at least five colors including the three primary colors and white, and a color represented by each of the signals included in the separated image signal A color image display device comprising: a monochromatic image display means capable of displaying the monochromatic image by simultaneous additive color mixing; and a driving means for driving the monochromatic image display means based on the separated image signal. 2. The image signal separating unit subtracts a white component from the input color image signal to generate a first subtraction result signal, thereby separating the input color image signal from a white image signal by a first subtraction. And a second subtraction color component, which is one of the first, second and third color mixtures, is subtracted from the first subtraction result signal. By generating a subtraction result signal, the first subtraction result signal is separated into a second subtraction color image signal and a second subtraction result signal. From the second subtraction result signal, the first color mixture, the second By subtracting a component of a third subtraction color, which is one of the mixed color and the third mixed color and a color other than the second subtraction color, to generate a third subtraction result signal,
The second subtraction result signal is separated into a third subtraction color image signal and a third subtraction result signal. From the third subtraction result signal, one of the first color mixture, the second color mixture, and the third color mixture The third subtraction is performed by subtracting a component of a fourth subtraction color that is one of the remaining colors other than the second subtraction color and the third subtraction color to generate a fourth subtraction result signal. Separating the result color signal into a fourth subtraction color image signal and a fourth subtraction result signal, and converting the input color image signal into a white image signal;
A second subtracted color image signal, a third subtracted color image signal, a fourth subtracted color image signal, and a fourth subtracted color image signal of the three primary colors.
2. The color image display device according to claim 1, wherein the color image is separated into a single color image signal of seven colors including a subtraction result signal. 3. The monochromatic image display means simultaneously adds a color represented by each of the signals included in the separated image signal in synchronism with the display of the transmissive monochrome image display means and the monochrome image display means. The color image display device according to claim 1, further comprising: a backlight light source capable of lighting a color by mixing colors. 4. The color image display device according to claim 3, wherein said monochrome image display means is a liquid crystal panel. 5. The monochromatic image signal included in the separated image signal is output as a serial signal to the monochromatic image display means in any order as the serial signal. The color image display device according to any one of the above items. 6. The driving means outputs the single-color image signal included in the separated image signal to the single-color image display means as a serial signal. 6. The color image display device according to claim 5, wherein the luminance information of the image signal is compared, and a signal having a higher luminance is output while being temporally positioned at the center in one frame. 7. The color image display device according to claim 1, wherein the three primary colors are red, green, and blue.