JPH08179737A - Liquid crystal display device and its driving method - Google Patents

Abstract

PURPOSE: To provide a liquid crystal display device in which a multicolor can be stably displayed. CONSTITUTION: To display a display color instructed by a video signal by color mixture of display colors between a plurality of display frames, a color liquid crystal display panel 31 of double refraction control system with high responding speed is used. The frequency of the display frame is set higher than the frame frequency of the video signal. A driving data generating circuit 19 generates a voltage data corresponding to the color displayed in each display frame so as to display the color instructed by the video signal. The voltage corresponding to the generated voltage data is applied to the color liquid crystal display panel 13 of each display frame to display the corresponding color, and the color instructed by the video signal is displayed by the visual color mixture of these colors.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a color liquid crystal display device using a liquid crystal display element for displaying a color corresponding to an applied voltage and a driving method thereof.

[0002]

2. Description of the Related Art An ordinary color display device obtains an arbitrary display color by additive color mixing of the three primary colors of red, green and blue, and has dots corresponding to the three primary colors of red, green and blue.
Arbitrary colors are displayed by controlling the brightness of the red, green, and blue dots independently. Therefore, a television set, a personal computer, or the like equipped with a color display device supplies three brightness data (image data) of red, green, and blue to the color display device to control the brightness of the dots of each color, Is displaying the desired color.

Similarly, in a color liquid crystal display element, one of three dots corresponding to the three primary color filters is selected.
The electrodes are arranged so as to form three pixels, and are driven so as to select the display color of one pixel composed of the three dots by independently controlling the intensity of light passing through each dot. .

The liquid crystal display device having the three primary color filters has a low light transmittance because each color filter absorbs light other than the color of the color filter.
For this reason, it is used in television sets, personal computers, etc. as a transmissive liquid crystal display device in which a powerful light source is arranged on the back surface. However, since the color liquid crystal display element has large light absorption by the color filter, it is not possible to obtain a reflection type color liquid crystal display device which does not require illumination from the back surface.

A birefringence control type liquid crystal display device is known as a liquid crystal display device capable of displaying a plurality of colors without using a color filter. A birefringence control type liquid crystal display element is composed of a liquid crystal cell in which liquid crystal is sealed between a pair of substrates subjected to an alignment treatment, and two polarizing plates arranged so as to sandwich the liquid crystal cell. Is applied to change the molecular alignment of the liquid crystal to change the birefringence effect of the liquid crystal layer to control the polarization state of the transmitted light, and this change of the polarization state changes the spectral distribution of the light transmitted through the liquid crystal cell. Display the desired color.

The birefringence control type liquid crystal display device can display a color without using a color filter, and the display is bright without light absorption by the color filter. Therefore, there is an advantage that a reflective color liquid crystal display device can be realized and the structure of the liquid crystal display element is simple.

[0007]

As described above, in the conventional birefringence control type liquid crystal display device, the colors that can be displayed depend on the applied voltage, and the kinds of colors that can be displayed are limited to the number of applied voltages. Has been. Therefore, there is a problem that an error occurs between the desired color and the displayed color. When the number of applied voltages is increased to increase the display colors, there is a problem that power consumption increases. Further, there is a problem that even if a color can be displayed by controlling the voltage, the color cannot be displayed stably because the range of the applied voltage that can display the color is narrow or the orientation is not stable.

The present invention has been made in view of the above situation, and an object thereof is to provide a liquid crystal display device capable of stably displaying an arbitrary color and a driving method thereof. Another object of the present invention is to provide a liquid crystal display device capable of displaying a color or the like which cannot be displayed due to applied voltage-display color characteristics, and a driving method thereof. Another object of the present invention is to provide a liquid crystal display device which can display a large number of colors and consumes less power, and a driving method thereof.

[0009]

In order to achieve the above object, a liquid crystal display device according to the present invention has a plurality of pixels arranged in a matrix, and a plurality of colors corresponding to an applied voltage are provided for each pixel. A liquid crystal display element to be displayed, a display color instructing means for instructing a display color of each of the plurality of pixels, and a display color instructed by the display color instructing means, the pixel is displayed by a mixture of display colors of a plurality of frames. In order to do so, a conversion means for converting the voltage applied to the pixel during a plurality of display frames into data indicating the data, and a drive means for applying a voltage corresponding to the data from the conversion means to drive the liquid crystal display element. The display color of each pixel is displayed by mixing the display colors of a plurality of frames of the pixel.

Further, a driving method of a liquid crystal display device according to the present invention is a driving method of a liquid crystal display device for displaying a color corresponding to an applied voltage in a pixel unit, and a display color instruction for indicating a display color of each pixel. A conversion step of outputting data corresponding to display colors of a plurality of frames for displaying the designated display color instructed by the display color instructing step by mixing colors of display colors of a plurality of frames of each pixel; Driving the liquid crystal display device in accordance with the data output by the step, and displaying the display color instructed by the display color instructing step by mixing the display colors of a plurality of frames of each pixel. To do.

[0011]

According to the structure of the present invention, a color that can be stably displayed is selected as a display color, and an arbitrary color can be displayed by mixing these colors on the time axis. Therefore, an arbitrary color can be stably displayed, and a color that cannot be displayed only by changing the applied voltage can be displayed. Furthermore, since the number of applied voltages can be limited, power consumption can also be suppressed.

[0012]

EXAMPLE A display device having an applied voltage-display color characteristic curve on a chromaticity diagram as shown in FIG. 8 has a color C on the chromaticity diagram.
Color CL4 located approximately in the middle of L1, CL2 and CL3
Can be displayed by mixing the colors CL1, CL2, and CL3. Therefore, in this embodiment, by using a liquid crystal display element capable of operating at a sufficiently high speed with respect to the frame frequency of the video signal,
As shown in FIG. 6, the frame frequency of the display image is set to three times the frame frequency of the video signal, and three images are displayed in one frame period of the video signal. The three images are visually synthesized by the afterimage phenomenon, and the viewer recognizes the image for one frame of the video signal.

An embodiment of a birefringence control type liquid crystal display device capable of performing such an operation will be described below with reference to the drawings. As shown in FIG. 1, this liquid crystal display device includes a drive circuit 11 and a liquid crystal display element 25.

The liquid crystal display element 25 comprises a birefringence control type active matrix liquid crystal display panel 31, a column driver 33 and a row driver 35.

As shown in FIGS. 1 and 2, a pixel electrode 43 and a TFT 45 whose source is connected to the pixel electrode 43 are provided on the lower substrate 41 of the pair of transparent substrates 41 and 51 which constitute the liquid crystal display panel 31. They are arranged in a matrix.
As shown in FIG. 1, gate lines (scanning lines) 47 are laid out in the row direction on the lower substrate 41.
Reference numeral 7 is connected to the gate electrode of the TFT 45 in the corresponding row. A data line (color signal line) 49 is arranged in the column direction and is connected to the drain of the TFT 45 in the corresponding column. Further, the lower substrate 41 has a structure shown in FIG.
As shown in FIG. 3, an alignment film 60 subjected to a predetermined alignment treatment is provided on the pixel electrode 43 and the TFT 45, and further, a polarizing plate 53 is provided on the back surface side thereof and aluminum or the like is provided on the back surface side of the polarizing plate 53. A reflector 55 made of metal is provided.

As shown in FIG. 2, a transparent counter electrode 58 facing each pixel electrode 43 is formed on the surface of the upper substrate 51 facing the lower substrate 41. An alignment film 59 that has been subjected to a predetermined alignment treatment is provided on the counter electrode 58. A retardation plate 52 is provided on the upper surface side of the upper substrate 51, and a polarizing plate 54 is provided on the upper surface side of the retardation plate 52. Both substrates 41 and 51 are joined together via a frame-shaped sealing material (not shown). A nematic liquid crystal 56 having a positive dielectric anisotropy, for example, is twist-aligned and enclosed between the substrates 41 and 51 by the alignment films 59 and 60.

The alignment direction of the liquid crystal molecules adjacent to the alignment film 59 of the upper substrate 51 is viewed from above, that is, from the observation side with respect to the alignment direction of the liquid crystal molecules adjacent to the alignment film 60 of the lower substrate 41 (azimuth angle 0 °). For example, the liquid crystal molecules are offset by 90 ° counterclockwise, and the liquid crystal molecules are almost 9 ° apart between the substrates 41 and 51.
It is twist-oriented with a twist angle of 0 °.

The transmission axis of the polarizing plate 54 is 30 ° from the observation side with respect to the azimuth angle of 0 °, and the transmission axis of the polarizing plate 53 is seen from the observation side with respect to the azimuth angle of 0 °. And the slow axis of the retardation plate 52 is obliquely displaced with respect to the transmission axis of the upper polarizing plate 54.

The liquid crystal display panel 31 is of a reflection type in which light incident from the upper polarizing plate 54 side is reflected by the reflection plate 55 and displayed. Incident light is transmitted through the upper polarizing plate 54 and the retardation plate 5.
2, the liquid crystal 56 and the lower polarizing plate 53 in order, and the reflecting plate 5
5, the reflected light is reflected by the lower polarizing plate 53 and the liquid crystal 5.
6, the phase difference plate 52 and the upper polarization plate 54 are sequentially emitted.

The linearly polarized light which has been polarized through the upper polarizing plate 54 becomes elliptically polarized light which is different for each wavelength light due to the birefringence effect in the process of passing through the retardation plate 52. The polarization state is further changed by the birefringence effect and emitted to the lower polarization plate 53, and only the polarization component of each wavelength light in the transmission axis direction of the lower polarization plate 53 is transmitted,
It is reflected by the reflector 55.

The reflected light is reflected by the lower polarizing plate 53, the liquid crystal 56,
Also, the polarization state is changed again due to the birefringence effect in the process of sequentially passing through the phase difference plate 52, and is incident on the upper polarizing plate 54 again. The light that has entered the upper polarizing plate 54 has only the polarized component in the transmission axis direction thereof transmitted, and is colored according to the wavelength light having the transmitted polarized component. The birefringence effect of the liquid crystal 56 changes according to the voltage applied to the liquid crystal 56, and the spectral distribution of the emitted light differs depending on the difference in the birefringence effect. That is, the light emitted from the liquid crystal display panel 31 is the liquid crystal 5
According to the voltage applied to 6, it is colored in a plurality of colors.

The column driver 33 (FIG. 1) is provided with a sample and hold circuit, samples the signals (write voltage V0 to V4 described later) supplied from the drive circuit 11, and samples the signals for one scanning line. Each signal is supplied to the corresponding data line 49.

The row driver 35 sequentially applies a gate pulse to the gate line 47. The TFT 45 connected to the gate line 47 to which the gate pulse is applied is turned on, and the voltage of the data line 49 is applied to the pixel electrode 43 connected to the turned on TFT 45.

The row driver 35 turns off the gate pulse immediately before the write voltage applied to the data line 49 is switched. Then, the TFT 45 is turned off, and the voltage applied until then is held in the pixel capacitance formed by the pixel electrode 43, the counter electrode 58, and the liquid crystal 56 between them. Therefore, during the non-selection period, the alignment state of liquid crystal molecules is maintained in a desired state, and a desired display color is maintained.

The relationship between the applied voltage and the display color is shown in FIG.
It can be expressed by the characteristic curve shown in. Here, all the colors on the characteristic curve can be displayed by controlling the applied voltage.
However, in practice, since the voltage range in which the color can be expressed is narrow, there are cases in which the color changes due to fluctuations in the power supply voltage, or the display color changes due to temperature changes.
Therefore, in this embodiment, only the voltages V0, V1, V2, V3 and V4 for stably displaying the reference colors of red, green, blue, black and white are applied to the liquid crystal 56, and the other colors are It is expressed by a color mixture between these color frames.

To enable such color mixture expression, the drive circuit 11 includes a control circuit 13, a writing circuit 15, and
It is composed of a frame memory 17, a voltage data generation circuit 19, a voltage generation circuit 21, and a multiplexer 23.

The write circuit 15 is a Y / C separation circuit, A
An A / D converter or the like is provided and an externally supplied analog video signal, for example, an NTSC analog TV signal is converted into 2-bit RGB brightness data (image) data indicating the brightness of each pixel and output. Frame memory 1
Reference numeral 7 has an odd frame memory 17A and an even frame memory 17B, each of which has a capacity for storing one frame of luminance data. Odd frame memory 17A
And the even frame memory 17B alternately store the RGB luminance data for one frame output from the writing circuit 15.

The voltage data generation circuit 19 has the structure shown in FIG. 3, and converts the RGB luminance data for each pixel read from the frame memory 17 into digital voltage data for 3 display frames of 3 bits.

More specifically, in this embodiment, as shown in FIG. 6, the liquid crystal display element 25 displays the image three times in one frame period of the video signal. When the five reference colors of red, green, blue, black, and white that can be directly displayed by controlling the applied voltage are displayed, all three colors of these three display frames are displayed. On the other hand, when displaying colors other than these five colors, by selecting and displaying an appropriate one of these colors, the three display frames are mixed and displayed.

In order to enable such an operation, the voltage data generation circuit 19 includes a distribution circuit 100, a monochromatic circuit 101, a color mixing circuit 102, and a selection circuit 103, as shown in FIG. The distribution circuit 100 determines whether the color indicated by the RGB luminance data supplied from the frame memory 17 is a color that can be directly displayed by applying the voltages V0 to V4 or a color expressed by mixed colors. The distribution circuit 100 supplies the supplied RGB luminance data to the monochromatic circuit 101 when the color can be directly displayed,
When the colors are displayed by color mixing, the color mixing circuit 102
Supply to.

The monochromatic circuit 101 outputs voltage data for instructing selection of these voltages when the RGB luminance data indicates a color that can be displayed by applying the voltages V0 to V4, that is, a reference color. Specifically, the monochrome circuit 101 is
For example, as shown in FIG. 4, an RG indicating these colors
A conversion table 11 for a single color in which voltage data indicating a voltage to be selected is stored at an address position having a value of B luminance data.
It consists of 1.

The color mixing circuit 102 sequentially outputs voltage data indicating the voltages to be applied to the corresponding pixels in the three display frames when the RGB luminance data indicates the colors to be displayed by the color mixing. Specifically, as shown in FIG. 5, the color mixing circuit 102 includes a color mixing conversion table 112 and a display frame counter 113. Conversion table 112 for color mixing
Stores the voltage data for each display frame at the address position having the RGB brightness data value. Further, the frame counter 113 is a ternary counter, and indicates which number of display frames in one video frame the current display frame is.

The selection circuit 103 outputs the output of the monochromatic circuit 101 and the color mixing circuit 1 according to the signal from the distribution circuit 100.
One of the outputs of 02 is selected and output to the multiplexer 23.

The voltage generating circuit 21 includes a voltage dividing circuit and the like, and generates five types of predetermined write voltages V0 to V4. The multiplexer 23 selects one of the five write voltages V0 to V4 generated by the voltage generation circuit 21 according to the output of the voltage data generation circuit 19 and supplies it to the column driver 33 of the liquid crystal display element 25.

The control circuit 13 controls the writing circuit 15 to write the RGB luminance data of the odd frame of the video signal in the memory 17A for the odd frame, and the RGB luminance data of the even frame of the video signal in the memory 1 for the even frame.
Write to 7B. The control circuit 13 also controls the RG from the even frame memory 17B for odd frames of the video signal.
The B brightness data is sequentially read, and the RGB brightness data is sequentially read from the odd frame memory 17A for the even frames of the video signal. As described above, the frame frequency of the display image is three times the frame frequency of the video signal. Therefore, the read speed is almost three times the write speed.
The control circuit 13 also controls the count value of the display frame counter 113.

The color mixing conversion table 112 is set as follows, for example. First, the characteristics of the birefringence control type liquid crystal display element 25 used (the characteristics of the change in the display color with respect to the applied voltage) are obtained as shown in the RGB color space of FIG. 7, for example. Next, the five reference colors that can be stably displayed and the writing voltages V0 to V4 necessary for displaying the colors are obtained.

Next, among 64 (2 ² × 2 ² × 2 ² ) colors defined by data of 2 bits for each of RGB and 6 bits in total, 59 colors other than the reference color are approximated in order to approximate the colors. Three reference colors to be mixed are obtained, and the voltage data corresponding to the selected reference colors are set in the color mixing conversion table 112 in an arbitrary order.

Next, the operation of the liquid crystal display device having the structure shown in FIGS. 1 to 5 will be described. The writing circuit 15 is the control circuit 1
Under the control of 3, R, G,
B is converted into 2-bit luminance data, and the memory 17
Store in A or 17B.

The control circuit 13 has a memory 17A or 17B.
From one side in a pixel unit (6 bit unit) at a frame frequency three times as high as the video signal, and the voltage data generation circuit 19
To supply to. RGB luminance data is red, green, blue, black,
When indicating white, that is, the reference color, the distribution circuit 100 in the voltage data generation circuit 19 supplies the supplied RGB luminance data to the single color circuit 101. The monochromatic circuit 101 outputs voltage data corresponding to the supplied RGB luminance data.

When the RGB luminance data indicates a color other than the reference color, the distribution circuit 1 in the voltage data generation circuit 19
00 supplies the supplied RGB luminance data to the color mixing circuit 102. The display frame counter 113 is the control circuit 1
The display frame number in one video frame is counted according to the control signal from 3 and the color mixing conversion table 11
2 outputs the supplied RGB luminance data and voltage data corresponding to the display frame number.

The selection circuit 103 is responsive to a control signal from the distribution circuit 100 to select the monochromatic circuit 101 or the mixed color circuit 1.
The voltage data output by 02 is selected and output. The multiplexer 23 selects the write voltages V0 to V4 output by the voltage generation circuit 21 according to the supplied voltage data and supplies the write voltages V0 to V4 to the column driver 33.

The column driver 33 samples the write voltage for one scanning line and supplies each sampled write voltage to the data line 49.

The row driver 35 sequentially applies a gate pulse to the gate line 47 to turn on the TFT 45, and the data line 49 to the TFT 45 are applied to the pixel electrode 43 of the selected row.
A voltage corresponding to the display color is applied via.

When the gate pulse is turned off, the TFT 45 is turned off, and the pixel electrode 43, the counter electrode 58 and the liquid crystal 5 between them.
The applied writing voltage is held in the capacitor formed by 6, and the alignment state of the liquid crystal molecules is maintained in a desired state during the non-selection period, the desired birefringence is maintained, and the display color is maintained.

By repeating such an operation, the color defined by the RGB luminance data stored in the frame memory 17 is displayed as a mixed color of the display colors of three frames of each pixel.

For example, when "blue" (000010) is designated as the display color of a pixel having a video signal, the voltage data generating circuit 19 follows the conversion table 111 for a single color to display the voltages in the first to third display frames. The data “010” is output. According to this voltage data, the multiplexer 2
3 is the write voltage "V2" in the first to third display frames
Is output. Therefore, as shown in FIG.
~ All "blue" is displayed in the third display frame.

When "dark blue" (000001) is designated as the display color of a pixel having a video signal, the voltage data generation circuit 19 follows the color mixing conversion table 112, for example, the first and third displays. The voltage data “010” is output to the frame, and the voltage data “011” is output to the second display frame. Therefore, the multiplexer 23
Write voltage "V2" in the first and third display frames.
And the write voltage “V3” is output to the second display frame. These voltages are applied to the corresponding display frames of the corresponding pixels, and as shown in FIG.
“Blue” → “black” → “blue” is displayed in the third display frame. These display colors are visually combined by the viewer to display "dark blue".

Similarly, for example, as shown in FIG. 6C, when the video signal indicates "bright blue" (000011), the voltage data is "010" → "100" → "010". Output and display "blue" → "white" → "blue". These display colors are visually combined by the viewer to display "bright blue".

As described above, according to this embodiment, the liquid crystal display element of the birefringence control system in which the frequency of the display frame is higher than the frame frequency of the video signal is used, and the colors to be actually displayed are set to five types. Limit and display any color by mixing colors. Therefore, it is possible to display a color that cannot be displayed stably, or a color that cannot be displayed due to the applied voltage-display color characteristics. Moreover, the number of write voltages can be suppressed.

The kind of color selected as the reference color and the combination of colors when displaying an arbitrary color are arbitrary.

The frame period of the NTSC system video signal is 60 Hz, and it is desirable that the display frame of the liquid crystal display element has a response speed of about 180 Hz or more. Also, for example, by thinning out the frames of the video signal,
When displaying at Hz, it is desirable that the display frame of the liquid crystal display element has a display frequency of about 90 Hz.

Also, when displaying a still image, it is desirable to display at a display frame frequency of about 30 Hz or higher so that the color of each display frame is independently recognized and flicker does not occur.

The present invention is not limited to the above embodiment, and various modifications and applications are possible. For example, in the above embodiment, an arbitrary color is displayed by mixing the display colors of the three display frames, but the number of frames used for the color mixing is arbitrary 2.
The above integer is sufficient.

In the above embodiment, the voltage data generation circuit 19
In the above, the RGB luminance data is converted into the voltage data by using the conversion table for the single color and the conversion table for the color mixture, but the image data may be converted into the voltage data by using another method. For example, by storing the same voltage data in the areas for the first to third display frames of the color-mixture conversion table 112, the color-mixture conversion table 11 can be displayed even when the primary colors are displayed.
2 may be used. With this configuration, the distribution circuit 100, the monochromatic circuit 101, and the selection circuit 103 can be eliminated. Further, the voltage data generation circuit 19 may be configured by a DSP (digital signal processor).

The number of bits of each data adopted in the above embodiment is an example, and the RGB luminance (image) data may have a number of bits other than 6 bits. 4 bits
It may be more than a bit. Similarly, the number of write voltages can be arbitrarily changed.

Further, in the above embodiment, the voltage generation circuit 21
The write voltage generated in step S1 is selected by the multiplexer 23 and supplied to the column driver 33. However, the voltage data output from the voltage data generation circuit 19 is D / A converted by the D / A converter.
It may be converted and supplied to the column driver 33.

In the above embodiment, the video signal is NTSC.
Although an example of using the TV signal of the system has been shown, for example, an analog RGB luminance signal supplied from a personal computer may be A / D converted and supplied to the voltage data generation circuit 19. In addition, the type of signal and the like are arbitrary.

In the liquid crystal display element in the above-mentioned embodiment, nematic liquid crystal having a positive dielectric anisotropy was twisted and used in the liquid crystal cell. However, the present invention is directed to a vertical molecular alignment (DAP) type using a cell in which liquid crystal molecules are homeotropically aligned, a parallel molecular alignment (homogeneous) type using a cell in which liquid crystal molecules are arranged in a twist-free homogeneous state, and a liquid crystal molecule. A hybrid molecular array (HAN) type cell using a hybrid molecular array cell in which the array is vertical on one substrate surface, parallel on the other substrate surface, and the array continuously changes between both substrates, or The present invention can be applied to various display elements such as a liquid crystal alignment mode type which uses a cell having a liquid crystal layer in which liquid crystal molecules change between splay alignment and bend alignment depending on a voltage. Further, in the above embodiment, the retardation plate was used, but depending on the arrangement of liquid crystal molecules,
It may be removed as appropriate. Further, the present invention is applicable not only to the reflective type but also to a transmissive type liquid crystal display element.

[0059]

As described above, according to the configuration of the present invention, the number of colors actually displayed can be limited, and any color can be displayed by mixing these colors on the time axis. Therefore,
It is possible to display a color that cannot be displayed only by applying a single voltage, or it is possible to display a color that cannot be displayed only by changing the applied voltage. Furthermore, since the number of applied voltages can be limited, power consumption can also be suppressed.

[Brief description of drawings]

FIG. 1 is a circuit diagram of a liquid crystal display device according to an embodiment of the present invention.

FIG. 2 is a cross-sectional view of a liquid crystal display panel.

FIG. 3 is a circuit diagram showing a circuit configuration of a voltage data generation circuit shown in FIG.

FIG. 4 is a diagram showing a configuration example of the monochromatic circuit shown in FIG.

5 is a diagram showing a configuration example of a color mixing circuit shown in FIG.

FIG. 6 shows a relationship between one frame of a video signal and a display frame, and liquid crystal display in three display frames within one frame of the video signal in order to display “blue”, “dark blue”, and “bright blue”. It is a figure which shows the example of the color which a panel displays.

FIG. 7 is an RGB chromaticity diagram showing the relationship between applied voltage and display color.

FIG. 8 is a diagram for explaining color mixing.

[Explanation of symbols]

11 ... Drive circuit, 13 ... Control circuit, 15 ... Writing circuit, 17 ... Frame memory, 17A ... Odd frame memory, 17B ... Even frame memory, 19 ... Voltage data generation circuit, 21 ... Voltage generation circuit, 23 ... Multiplexer, 25 ... Liquid crystal display element, 31 ... Liquid crystal display panel, 33 ... Column driver, 35 ... Row driver, 41・ ・
-Substrate, 43 ... Pixel electrode, 45 ... Thin film transistor (TFT), 47 ... Gate line, 49 ... Data line, 51 ... Substrate, 52 ... Phase difference plate, 53 ... ·Polarizer,
54 ... Polarizing plate, 55 ... Reflecting plate, 56 ... Liquid crystal, 58 ...
Counter electrode, 59 ... Alignment film, 60 ... Alignment film, 100 ...
Sorting circuit, 101 ... Monochromatic circuit, 102 ... Color mixing circuit, 103 ... Selection circuit, 111 ... Monocolor conversion table, 112 ... Mixing color conversion table, 113 ... Display frame counter

Claims (6)

[Claims] 1. A liquid crystal display element having a plurality of pixels arranged in a matrix and displaying a plurality of colors according to an applied voltage in a pixel unit, and a display for indicating a display color of each of the plurality of pixels. A color instructing unit, and a display color instructed by the display color instructing unit, in order to display the pixel by a mixture of display colors of a plurality of frames,
It comprises a conversion means for converting into a data indicating a voltage to be applied to the pixel during a plurality of frames, and a drive means for applying a voltage corresponding to the data from the conversion means to drive the liquid crystal display element. Is
A liquid crystal display device, wherein a display color of each pixel is displayed by a mixture of display colors of a plurality of frames of the pixel. 2. The converting means applies a same voltage to a plurality of frames according to a designated display color designated by the display color designating means, and a means to apply different voltages to a plurality of frames. The liquid crystal display device according to claim 1, further comprising means for selectively driving both means. 3. The liquid crystal display device according to claim 1, wherein the liquid crystal display element has a response speed for displaying a designated color within each frame period. 4. The liquid crystal display element is a birefringence control type liquid crystal display element.
The liquid crystal display device according to item 1. 5. A driving method of a liquid crystal display device for displaying a color according to an applied voltage in units of pixels, comprising a display color instructing step for instructing a display color of each pixel, and an instruction by the display color instructing step. A conversion step of outputting data corresponding to the display colors of the plurality of frames in order to display the designated display color in a mixed color of the display colors of the plurality of frames of each pixel, and the liquid crystal display device according to the data output by the conversion step. A driving method of a liquid crystal display device, which comprises a driving step, and displays a display color instructed by the display color instructing step by mixing display colors of a plurality of frames of each pixel. 6. The display color designating step comprises n for each pixel.
(N is an integer of 2 or more) The display color is instructed in frame units, and the conversion step displays the designated display color instructed in the display color instructing step to The step of outputting the applied voltage,
The method for driving a liquid crystal display device according to claim 5, wherein.