JP2006330311A - Liquid crystal display device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a liquid crystal display device which suppresses flicker while improving an image quality of moving images. <P>SOLUTION: The liquid crystal display device includes; a display panel which has a plurality of scan lines, a plurality of data lines, a plurality of pixel electrodes disposed at intersections between the scan lines and data lines, and a liquid crystal layer provided between the pixel electrodes and a counter electrode; a back light provided on the rear side of the display panel; and a drive control circuit which performs panel drive of applying a display voltage corresponding to display data from data lines to the plurality of pixel electrode while scanning the scan lines. The drive control circuit controls blinking of the back light so as to satisfy F<f<2F and f=F×(N+1)/N wherein F is a frame frequency for input of display data and (f) is a frequency for blinking of the back light, so that a blinking period of the back light is approximated to the frame frequency as much as possible to improve the image quality of moving images while the blinking frequency of the back light is made higher than the frame frequency to suppress flicker sensed by human eyes. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a liquid crystal display device, and more particularly to a liquid crystal display device that improves the image quality of moving images and reduces flicker.

  The liquid crystal display device includes a plurality of scanning lines extending in the horizontal direction, a data line extending in the vertical direction, a switch composed of TFTs arranged at intersections thereof, a pixel electrode connected to the switch, and a pixel electrode. A common electrode provided opposite to the pixel electrode and a liquid crystal layer disposed between the pixel electrode and the common electrode. Then, the TFT is turned on while scanning the scanning line within the frame period, the voltage applied to each pixel is supplied from the data line, the voltage corresponding to the image data is applied to each pixel electrode, and the liquid crystal layer and before and after The transmittance of the panel made of the provided polarizing plate is changed. A backlight is provided on the back surface of the panel, and light from the backlight is transmitted to the display side according to the transmittance of the panel, thereby displaying a desired luminance gradation value.

  Since the liquid crystal molecules of the liquid crystal display device are a hold type that has a slow response to the applied voltage and the brightness of each pixel is kept constant during the frame period, moving the backlight constantly blurs the motion of the video. It causes deterioration. Therefore, it has been proposed to limit the display period to a certain period within the frame period in synchronization with the vertical synchronization signal of the image signal. For example, Patent Document 1 below.

  Further, in the following Patent Documents 2, 3, 4, and 5, the backlight is divided into a plurality of display areas, and the backlight is intermittently turned on sequentially in synchronization with the frame period. It has also been proposed to limit to a certain period.

Further, according to Patent Document 6, when dimming by pulse width modulation is performed by changing the duty ratio of lighting and extinguishing by repeatedly turning on and off the backlight, an odd number of times between a plurality of frame periods. A liquid crystal display device has been proposed in which flickering due to dimming is suppressed by turning on at a frequency higher than the frame frequency. In Patent Document 6, the dimming frequency f of PWM dimming is f = m * F / n (n is an integer greater than 2, m> n, and the display driving frequency (frame frequency) F of the panel. It is described that the relationship of m ≠ 2n) is established.
Japanese Patent Laid-Open No. 9-325715 JP-A-11-202285 JP-A-11-202286 JP 2000-321551 A JP 2001-125066 A Japanese Patent No. 3027298

  In Patent Documents 1 to 5, the backlight is blinked at 60 Hz, which is a panel drive frequency (frame frequency), in order to improve the image quality of moving images. For this reason, the blinking of the backlight is perceived as flicker by human eyes. That is, if the blinking frequency of the backlight is as low as about 60 Hz, human eyes feel flicker. As described above, blinking of the backlight and flicker suppression for improving the image quality of moving images are contradictory technical issues.

  On the other hand, in Patent Document 6, the blinking frequency of the backlight for dimming is as high as 60 × 5/2 = 150 Hz, and flicker is not felt, but it is not synchronized with the panel driving frequency. The image quality cannot be increased.

  Accordingly, an object of the present invention is to provide a liquid crystal display device that suppresses flicker while improving the image quality of moving images.

  In order to achieve the above object, according to the first aspect of the present invention, a plurality of scanning lines, a plurality of data lines, and a plurality of pixel electrodes arranged at intersections thereof are provided. In a liquid crystal display device having a display panel having a liquid crystal layer provided between the counter electrode and a backlight provided on the back side of the display panel, the plurality of data lines are scanned from the data line while scanning the scanning line. A drive control circuit for performing panel drive for applying a display voltage corresponding to display data to the pixel electrode, the drive control circuit having a frequency at which the backlight blinks with respect to a frame frequency F to which the display data is input; The blinking of the backlight is controlled so that f is F <f <2F and f = F × (N + 1) / N (N is a positive integer).

  According to the first aspect described above, for example, when N = 4, blinking control is performed so that the backlight is turned on five times during a four-frame period, and the backlight lighting cycle matches the frame cycle as much as possible. By doing so, you can improve the quality of the video. On the other hand, the lighting frequency of the backlight is set to 75 Hz, which is 20% higher than the frame frequency of 60 Hz, so that flicker felt by human eyes can be suppressed. This is because human eyes will not feel flicker if it blinks at least 70 to 75 Hz.

  In the first aspect described above, according to a preferred embodiment, the pulse width or pulse amplitude of the Nth lighting pulse from the head of the lighting pulse group among the N + 1 lighting pulse groups given to the N frame group is set. , Make it smaller than that of other lighting pulses. As a result, it is possible to reduce the lighting luminance due to the Nth lighting pulse that extends over two adjacent frame periods, and to suppress the deterioration of the image quality of the moving image.

  In the first aspect described above, according to a preferred embodiment, of the N + 1 lighting pulse groups given to the N frame group, the Nth lighting pulse from the head of the lighting pulse group is set to a predetermined length longer than the frame period. Is not generated every period (for example, about 1 second) and the backlight is not turned on. As a result, the number of times of lighting by the Nth lighting pulse spanning two adjacent frame periods can be reduced, the average luminance by the Nth lighting pulse can be lowered, and deterioration in the image quality of the moving image can be suppressed.

  In the first aspect described above, according to a preferred embodiment, the drive control circuit includes a dimming unit that modulates the lighting pulse width for controlling the blinking of the backlight in accordance with the dimming level. According to this, a dimming function can be realized, and the lighting pulse frequency of pulse width modulation for dimming can be made higher than the frame frequency F, and flicker caused thereby can be suppressed.

  In the first aspect described above, according to a preferred embodiment, the backlight is divided into a plurality of regions for each predetermined number of scanning lines on the display panel, and the drive control circuit includes the divided backlight regions. , Blinking drive control is performed in correspondence with the frame phases of a predetermined number of scanning lines. As a result, the backlight area can be controlled to blink in accordance with the frame phase of each of the plurality of areas for each predetermined number of scanning lines, and the image quality of the moving image can be further improved.

  In order to achieve the above object, according to a second aspect of the present invention, a plurality of scanning lines, a plurality of data lines, and a plurality of pixel electrodes arranged at intersections thereof, In a liquid crystal display device having a display panel having a liquid crystal layer provided between the counter electrode and a backlight provided on the back side of the display panel, the plurality of data lines are scanned from the data line while scanning the scanning line. A drive control circuit that performs panel drive to apply a display voltage corresponding to display data to the pixel electrode, and the drive control circuit performs the panel drive at twice the frame frequency F to which the display data is input; The backlight blinking is controlled so that the frequency f at which the backlight blinks is F <f <2F and f = F × (N + 1) / N with respect to the frame frequency F. Then, the backlight lighting period is controlled so that the probability of occurrence in the second half panel drive period within the frame period is higher than the probability of occurrence in the first half panel drive period.

  According to the second aspect, since the backlight is turned on more frequently in the latter half of the panel driving period when the liquid crystal molecules in the liquid crystal layer are in a stable state with respect to the double speed driving, the image quality of the moving image can be improved. it can. Further, since the blinking frequency of the backlight is higher than the frame frequency, flicker can be suppressed.

  In the second aspect, according to a preferred embodiment, the drive control circuit includes a voltage corresponding to interpolation data obtained based on display data of the frame and display data of the previous frame in the first half panel drive. In the latter half of the panel drive, a voltage corresponding to the display data of the frame is applied.

  In the second aspect, according to a preferred embodiment, the drive control circuit corresponds to the overdrive data obtained based on the display data of the frame and the display data of the previous frame in the panel driving of the first half. A voltage is applied, and in the latter half of the panel drive, a voltage corresponding to the display data of the frame is applied.

  According to the present invention, since the lighting of the backlight is synchronized with the frame period as much as possible, the image quality of the moving image can be improved, and the flicker frequency of the backlight is higher than the frame frequency, and flicker Flickers at a high frequency so that no flicker can be felt.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. However, the technical scope of the present invention is not limited to these embodiments, but extends to the matters described in the claims and equivalents thereof.

  FIG. 1 is an overall configuration diagram of a liquid crystal display device according to the present embodiment. The display panel PA includes a plurality (L) of scanning lines SC, a plurality of data lines D intersecting with the scanning lines SC, a switch including a thin film transistor TFT disposed at the intersecting position, a pixel electrode PX connected thereto, The liquid crystal layer LC is provided between the pixel electrode PX and the common electrode CM facing the pixel electrode PX. The display panel PA is provided with a polarizing plate (not shown). A backlight BL is provided on the back side of the display panel. The backlight BL is divided into a plurality of regions BL1 to BL4 for each predetermined number of scanning lines, and lighting control is performed by lighting pulses from the corresponding BL power sources P1 to P4.

  The scanning line SC is driven by a scanning line driver SDR, and a voltage corresponding to display data is applied from the data driver to the data line D. The scanning line SC also serves as the gate electrode of the transistor TFT. When the scanning line is driven, the transistor becomes conductive, and the voltage applied to the data line is applied to the pixel electrode PX. In response to the application of the data voltage, the alignment state or inclination of the liquid crystal molecules in the liquid crystal layer LC changes, and the light transmittance of the display panel having the polarizing plate changes. In this state, when the backlight is turned on, the light is transmitted to the display side with a light amount corresponding to the light transmittance of the display panel, and the display luminance corresponding to the display data is reproduced.

  The liquid crystal display device is provided with a drive control circuit 10, and the drive control circuit 10 inputs display data and a synchronization signal in synchronization with the frame period. The drive control circuit 10 includes a scanning line control unit 12 that controls the scanning line driver, and display data conversion means 14 that performs predetermined image processing on display data given in line sequential order and converts the display data into display data for each scanning line. And a backlight control unit 16 that controls the power sources P1 to P4 of the backlight.

[First Embodiment]
FIG. 2 is a diagram illustrating the drive timing in the first embodiment. FIG. 2 shows the signals of the leading scanning lines (first, L / 4th, 2L / 4th, 3L / 4th) of four areas of the L scanning lines and four light emitting areas (backlight areas). ) Brightness change is shown. The luminance change in the light emitting area indirectly indicates the driving pulses of the four backlight light emitting areas. In the first embodiment, the backlight lighting cycle f _BL is f _BL = F _FL × (N + 1) / N (N is a positive integer) with respect to the frame cycle F _FL and F _FL <f _BL < Controlled to be 2F _FL . FIG. 2 shows an example of N = 4.

  That is, the backlight is controlled to be turned on 5 (= N + 1) times in the period 4FL of the frame group including 4 (= N) frame periods FL1 to FL4. As a result, out of the five lightings of the backlight, the first, second, third, and fifth lightings correspond to the timings of the four frame periods FL1 to FL4, respectively. It is performed across the frame periods FL4 and FL5. That is, except for the fourth backlight lighting, the backlight lights in synchronization with the frame period, so that the quality of the moving image can be improved. At the same time, the lighting frequency of the backlight is 75 Hz, which is 5/4 times 60 Hz of the frame frequency. Since the blinking frequency of 75 Hz is not less than the minimum frequency (70 to 75 Hz) at which the human eye does not feel flicker, the occurrence of flicker can be suppressed with this backlight blinking control.

  As shown in FIG. 1, the light emission area of the backlight is divided into four. Accordingly, the phase of the lighting pulse is controlled corresponding to the frame phase of the first scanning line for the light emitting region BL1. In this case, the lighting pulse has a lighting frequency of 4: 5 with respect to the frame frequency. Similarly, the phase control of the lighting pulse in the light emitting region BL2 is performed corresponding to the frame phase of the L / 4 scanning line, and the lighting pulse in the light emitting region BL3 corresponding to the frame phase of the 2L / 4 scanning line. The phase control of the lighting pulse in the light emitting region BL4 is performed corresponding to the frame phase of the 3L / 4th scanning line. In this case as well, each lighting frequency has a 4: 5 relationship with the frame frequency.

The ratio of the backlight lighting frequency f _{BL to} the frame frequency F _FL is N: N + 1, but when the integer N increases to 5, the backlight lighting frequency approaches the frame frequency of 60 Hz, and thus flicker suppression is insufficient. Become. On the other hand, if the integer N is smaller than 4, the occurrence frequency of the Nth lighting pulse that is not suitable for the image quality of the moving image is increased, which is not preferable. Accordingly, the integer N = 4 is the optimum value. Or even if N = 3, 5, flicker can be suppressed to some extent and the image quality of the moving image can be improved.

  FIG. 3 is a diagram showing a comparison between the conventional backlight drive and the backlight drive of the present embodiment. In this figure, the horizontal position (horizontal axis) of an image that moves to the right side with time in the display screen is shown in correspondence with the time axis (vertical axis). Further, frame periods FL1 to FL4 are shown in the time axis direction, and a backlight lighting pulse BLp is shown.

  In the conventional method (A) shown on the left side, since the backlight lighting pulse BLp is generated in complete synchronization with the frame periods FL1 to FL4, the backlight is lit only once in each frame period. Accordingly, the position of the image that moves to the right also moves at a constant speed corresponding to the frame period. On the other hand, according to the present embodiment (B) shown on the right side, five backlight lighting pulses BLp are generated for the four frame periods FL1 to FL4. The first, second, third and fifth lighting pulses are generated corresponding to the frame periods FL1 to FL4, respectively, but the fourth lighting pulse is generated across the frame periods FL3 and FL4. The moving images of FL3 and 4 are turned on. Such a moving image is displayed as a so-called blurred image, which causes a reduction in the quality of the moving image. In the present embodiment, since the fourth lighting pulse is generated only once every five times, the influence of the all lighting pulses on the moving image is not so great, but if possible, the moving image display of the fourth lighting pulse is It is desired to reduce the influence as compared with the moving image display of other lighting pulses.

  FIG. 4 is a diagram illustrating a modification of the first embodiment. Even in this modification, lighting is performed five times during the four-frame period 4FL. In this modification, the fourth lighting pulse width in the four-frame period group 4FL is made narrower than the other lighting pulse widths to prevent the degradation of the moving image quality described with reference to FIG. The lighting brightness of is lower than the other lighting brightness. That is, in the luminance change signal in FIG. 4, the broken line in the case of the same lighting pulse width is improved as a solid line. This lighting pulse width is preferably about 85% of other pulse widths. For example, while the other lighting pulse width is 5.3 msec, the fourth lighting pulse width is set to about 4.6 msec. With this level, it is possible to suppress a reduction in the quality of the moving image without causing flicker. In that case, (1) the leading end of the lighting pulse is advanced and the beginning is equally spaced with other lighting pulses, (2) the leading end of the lighting pulse is delayed and the trailing end is equally spaced with other lighting pulses, (3) Either the center of the lighting pulse is equally spaced from other lighting pulses, the head is delayed and the trailing edge is advanced. In any control, the fourth lighting pulse width is narrowed and the lighting time is shortened, so that it is possible to suppress the deterioration of the image quality of the moving image.

  FIG. 5 is a diagram illustrating another modification of the first embodiment. Even in this modification, lighting is performed five times during the four-frame period 4FL. In this modified example, in order to prevent the deterioration of the image quality of the moving image described with reference to FIG. 3, the amplitude of the fourth lighting pulse in the 4-frame period group 4FL is made lower than the amplitudes of the other lighting pulses, The fourth lighting luminance is set lower than other lighting luminances. That is, in the luminance change signal in FIG. 5, the broken line in the case of the same lighting pulse amplitude is improved as a solid line. The lighting pulse amplitude is preferably about 90% of the other lighting pulse amplitudes. For example, another lighting pulse is driven at 7.0 mA, and the fourth lighting pulse is driven at 5.9 mA. With this level, it is possible to suppress a reduction in the quality of the moving image without causing flicker.

  FIG. 6 is a diagram showing still another modification of the first embodiment. In this modification, the liquid crystal display device is provided with a dimming function. That is, a dimming switch 22 for adjusting the brightness of the display panel from the outside is provided, and in response to control from the dimming switch, the dimming control unit 20 transmits a backlight lighting pulse from the drive control circuit 10. The duty ratio is variably controlled by pulse width modulation. A variably controlled lighting pulse signal is applied to the backlight power sources P1 to P4, and the divided lighting areas are driven to light. For example, it is possible to reduce the luminance of the display panel PA by reducing the duty ratio by delaying the leading edge of the lighting pulse signal. By delaying the leading edge, the lighting period can be generated as late as possible in the frame period, and the liquid crystal molecules can be lit in a more stable state.

  Also in this modification, lighting is performed five times during the four frame period 4FL. However, each lighting pulse width is variably controlled according to dimming control from the dimming switch 22. Therefore, since the backlight is turned on in synchronization with the frame period as much as possible, the image quality of the moving image can be improved. Furthermore, although it has a dimming function by pulse width modulation, the frequency of the lighting pulse is controlled to 75 Hz, which is about 20% higher than the frame frequency of 60 Hz, so that human eyes hardly feel flicker.

  In still another modification of the first embodiment, the backlight lighting control is performed so that the fourth lighting pulse is thinned out about every second. That is, in order to prevent the degradation of the image quality of the moving image described with reference to FIG. 3, the fourth lighting pulse in the 4-frame period group 4FL is not generated about every second, and the lighting luminance is higher than the luminance due to the other lighting pulses. Is low. That is, the first, second, third, and fifth lighting pulses are generated 15 times per second, but the fourth lighting pulse is generated only 14 times. Therefore, the average luminance in the time axis space due to the fourth lighting pulse can be made lower than that of other lighting pulses, and the deterioration of the image quality of the moving image can be suppressed. Further, it is desirable to reset the first lighting pulse so as to coincide with the frame period immediately after the fourth lighting pulse is thinned out.

[Second Embodiment]
In the second embodiment, when driving at double speed in order to improve the response of the liquid crystal, the image quality of the moving image is improved and flicker is suppressed. It takes some time for the liquid crystal molecules to change to a position corresponding to the voltage in response to the voltage application. In particular, when the display gradations of the previous frame and the current frame are greatly different, the delay time becomes longer. This poor responsiveness also affects the degradation of the image quality of moving images.

  In view of this, in the liquid crystal display device, double speed driving in which panel driving is performed twice in one frame period has been proposed. For example, a method of driving with the voltage of the display data of the previous frame and the display data of the current frame in the first half of the frame period and the voltage of the display data of the current frame in the second half of the frame period, For example, the liquid crystal molecules are driven at the high speed by driving with an overdrive voltage in the first half of the period, and the liquid crystal molecules are stabilized by driving at a voltage corresponding to display data of the current frame in the second half of the frame period. The overdrive voltage is a voltage that is higher than the voltage of the corresponding frame when the applied voltage changes in the direction of increasing, and the voltage that is lower than the voltage of the corresponding frame when the applied voltage changes in the direction of decreasing. is there.

  FIG. 7 is a drive timing chart in the case of driving with the above-described interpolation value. In the figure, the first scanning line signal is scanned in the first half 11A of the frame period FL1, and is scanned again in the second half 11B. In the subsequent frame periods FL2, FL3, and FL4, scanning is performed in the first half 12A, 13A, and 14A, and scanning is performed again in the second half 12B, 13B, and 14B. In the figure, the input gradation signal for the pixel on the first scanning line in each of the frame periods FL1 to Fl4 is shown, but the pixel gradation signal (circuit output) actually applied to the pixel is the frame. In the first half of the period, the input gradation signal of the previous frame and the input gradation signal of the current frame are averaged (interpolated value), and in the second half of the frame period, the input gradation signal of the current frame is obtained. By driving in this way, the movement of the image in the moving image becomes smooth. However, since the period driven by the interpolation value is different from the input gradation signal, there is a sense of incongruity in the color. Therefore, the lighting of the backlight is limited to the second half of the frame period as shown by the luminance change in the figure. Is preferred.

  FIG. 8 is a drive timing chart in the case of driving with the overdrive described above. In this case as well, double-speed driving is performed in which the scanning lines are scanned in a half period of the frame period as in FIG. Taking the first scanning line as an example, in the first half 11A, 12A, 13A, and 14A of the frame period, the pixel is driven by the voltage of the pixel gradation signal (circuit output) overdriven from the pixel input gradation signal. In the second half 11B, 12B, 13B, and 14B of the frame period, the pixels are driven with a voltage corresponding to the pixel input gradation signal of the current frame. By such overdrive, the response of the liquid crystal molecules is accelerated so that the change of the moving image can follow the frame period. In this case, the liquid crystal is in the process of changing during the overdrive period, so the gradation value is different from the input gradation signal. Therefore, it is preferable that the lighting of the backlight is limited to the second half of the frame period, as indicated by the luminance change in the figure.

  As shown in FIG. 7 and FIG. 8, when driving at double speed, it is preferable to turn on the backlight in the second half of the frame period in which the liquid crystal molecules are more stable. However, in that case, the lighting cycle of the backlight coincides with the frame cycle, the lighting frequency of the backlight becomes about 60 Hz, and flicker occurs. Therefore, in the second embodiment, even when driving at double speed, the backlight lighting frequency is set to about 75 Hz, which is the minimum frequency in a range where flicker is not felt. Therefore, as in the first embodiment, five lighting pulses are generated in four frame periods. However, the backlight lighting period is controlled so as to be biased toward the latter half rather than the first half of the frame period (probably exceeding 50%).

  In the above embodiment, the backlight lighting frequency is set to 75 Hz while the panel is driven at twice the frame frequency (60 Hz). Therefore, it can be understood that the frame frequency and the lighting frequency are repeated at a predetermined timing combination every least common multiple cycle of both frequencies. In that case, the timing combination is selected such that the backlight lighting period is biased toward the second half rather than the first half of the frame period. Thereby, the backlight can illuminate the state in the latter half of the frame period when the liquid crystal molecules of the panel are stable.

  FIG. 9 is a diagram illustrating the drive timing in the second embodiment. In FIG. 9, as in FIGS. 7 and 8, panel driving is performed at a double speed of the frame period. Then, the lighting frequency of the backlight is set to 75 Hz with respect to the frame frequency of 60 Hz, thereby suppressing the occurrence of flicker. That is, the lighting period of the backlight is controlled so as to be shown as a luminance change signal in the drawing. The phase of the lighting pulse of the backlight is controlled so that the lighting period is generally in the latter half of the first half of the frame period. By doing so, the liquid crystal molecules are in a more stable state and the backlight is turned on in the latter half of the frame corresponding to the input gradation signal (display data), so that the image quality of the moving image is improved. Note that the backlight is turned off as much as possible during the first half of the frame. In the second embodiment, the lighting area of the backlight is one in the panel, but may be divided into a plurality of areas.

  In the second embodiment, the backlight is controlled to be lit at a frequency of 75 Hz, while the input display data is given at a frequency of 60 Hz and is driven at the double speed. The phase gradually shifts from the writing phase. Therefore, in order to match the phases of the two, the phase of the lighting pulse timing is reset at a period of about 2 seconds so as to coincide with the writing phase. Specifically, when the L × (120 + 3/4) th scan is completed with respect to the number L of scanning lines in the display panel, the timing of the lighting pulse is reset and the phase of the write timing (double frame speed). Phase) and the phase difference to zero.

  As described above, in the second embodiment, when the panel is driven at double speed, flicker can be suppressed and the quality of a moving image can be improved.

1 is an overall configuration diagram of a liquid crystal display device in the present embodiment. It is a figure which shows the drive timing in 1st Embodiment. It is a figure which shows the comparison with the conventional backlight drive and the backlight drive of this Embodiment. It is a figure which shows the modification in 1st Embodiment. It is a figure which shows another modification in 1st Embodiment. It is a figure which shows another modification in 1st Embodiment. It is a drive timing diagram in the case of driving with an interpolation value. It is a drive timing diagram in the case of driving by overdrive. It is a figure which shows the drive timing in 2nd Embodiment.

Explanation of symbols

10: Drive control circuit SC: Scan line D: Data line TFT: Switch transistor PX: Pixel LC: Liquid crystal layer PA: Display panel BL: Backlight

Claims (9)

A display panel having a plurality of scanning lines, a plurality of data lines, and a plurality of pixel electrodes arranged at intersections thereof, and further comprising a liquid crystal layer provided between the pixel electrode and the counter electrode;
In a liquid crystal display device having a backlight provided on the back side of the display panel,
A drive control circuit that performs panel driving to apply a display voltage corresponding to display data from the data line to the plurality of pixel electrodes while scanning the scanning line;
The drive control circuit is configured such that the frequency f at which the backlight blinks is F <f <2F and f = F × (N + 1) / N (N is a positive value) with respect to the frame frequency F to which the display data is input. The liquid crystal display device is characterized by controlling the blinking of the backlight so as to be an integer.   2. The liquid crystal display device according to claim 1, wherein the drive control circuit performs a blinking control so that N = 4 and the backlight is turned on five times during a period of four frames.   2. The drive control circuit according to claim 1, wherein, among the N + 1 lighting pulse groups given to the N frame group, the drive control circuit sets a pulse width or a pulse amplitude of the Nth lighting pulse from the head of the lighting pulse group to other values. A liquid crystal display device characterized by being smaller than that of a lighting pulse.   2. The drive control circuit according to claim 1, wherein among the N + 1 lighting pulse groups given to the N frame group, the drive control circuit outputs the Nth lighting pulse from the head of the lighting pulse group at a predetermined cycle longer than the frame cycle. The liquid crystal display device is characterized in that it does not occur and the backlight is not turned on.   2. The liquid crystal display device according to claim 1, wherein the drive control circuit includes dimming means for modulating a lighting pulse width for controlling blinking of the backlight according to a dimming level.   2. The backlight according to claim 1, wherein the backlight is divided into a plurality of regions for each predetermined number of scanning lines on the display panel, and the drive control circuit divides the divided backlight region into a predetermined number of scanning lines, respectively. A liquid crystal display device that performs blinking drive control in accordance with each frame phase. A display panel having a plurality of scanning lines, a plurality of data lines, and a plurality of pixel electrodes arranged at intersections thereof, and further comprising a liquid crystal layer provided between the pixel electrode and the counter electrode;
In a liquid crystal display device having a backlight provided on the back side of the display panel,
A drive control circuit that performs panel driving to apply a display voltage corresponding to display data from the data line to the plurality of pixel electrodes while scanning the scanning line;
The drive control circuit performs the panel drive at twice the frame frequency F to which the display data is input, and the frequency f at which the backlight blinks is F <f <2F with respect to the frame frequency F. Further, the blinking of the backlight is controlled so that f = F × (N + 1) / N. Further, the probability that the backlight lighting period will occur in the panel driving period in the latter half of the frame period is in the first half. A liquid crystal display device which is controlled to be higher than the probability of occurrence in a driving period.   8. The drive control circuit according to claim 7, wherein, in the first half panel drive, the drive control circuit applies a voltage corresponding to display data of the frame and interpolation data obtained based on the display data of the previous frame, and the second half panel drive. And applying a voltage corresponding to the display data of the frame.   8. The drive control circuit according to claim 7, wherein in the first half panel drive, the drive control circuit applies a voltage corresponding to display data of the frame and overdrive data obtained based on the display data of the previous frame, and A liquid crystal display device characterized by applying a voltage corresponding to display data of the frame in driving.

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