JP2001154639A - Liquid crystal display device and driving method therefor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To perform complete blanking display for a blanking period when scanning signal lines of a liquid crystal panel are more than scanning lines for one vertical period of an image input signal. SOLUTION: For an image display period, scanning signals S14-61 to S14-1140 are sequentially outputted once in a single horizontal period of the image input signal (in) from a scanning signal circuit 14, and pixel data signals S13-1 to S13-m are inputted to the liquid crystal panel 15 from a display signal circuit 13. For a blanking period, plural input pulses S11b are inputted to the scanning signal circuit 14 synchronizing with a high speed clock signal S11c, and an input pulse S11b is shifted up to a blanking position. After blanking has been written in 30-odd number lines on the upper side of the liquid crystal panel 15 at the same time, blanking is written in 30-even number lines on the upper side at the same time. Similarly, after blanking has been written in 30-odd number lines on the lower side of the liquid crystal panel 15 at the same time, blanking is written in 30-even number lines on the lower side at the same time.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a display device using a liquid crystal panel, and more particularly, to a liquid crystal display provided with a function of performing a complete blanking display during a blanking period in which there are no upper and lower images on a screen. The present invention relates to an apparatus and a driving method thereof.

[0002]

2. Description of the Related Art Conventionally, this type of liquid crystal display device has a control unit 1 and an oscillation circuit 2 as shown in FIG.
Receives an image input signal in supplied from the outside and a clock signal S2 supplied from the oscillation circuit 2, and inputs an image data signal S1a, an input pulse S1b for generating a scanning signal, and a clock signal
It has a function of generating and outputting S1c and an output enable signal S1d. A display signal circuit 3 and a scanning signal circuit 4 are connected to the control unit 1. The display signal circuit 3 receives the image data signal S1a and receives the pixel data signals S3-1,.
This circuit generates and outputs m. The scanning signal circuit 4
It has a shift register that receives an input pulse S1b and moves in synchronization with the clock signal S1c, and has an output enable signal S1d
Is input, the input pulse S1b is output to the scanning signals S4-1 and S4-1.
…, A circuit that outputs as S4-n. The output side of the display signal circuit 3 is connected to the data signal lines Y1,..., Ym of the liquid crystal panel 5, and the output side of the scanning signal circuit 4 is connected to the scanning signal lines X1,. ing. LCD panel 5
Has a plurality of pixel regions provided at intersections of the data signal lines Y1,..., Ym and the scanning signal lines X1,..., Xn, and the scanning signals S4-1,. , S3-n, the image is displayed by supplying the pixel data signals S3-1,..., S3-m to the pixel area selected by S4-n.

FIG. 6 is a time chart of signals of respective parts for explaining the operation of the above-mentioned conventional liquid crystal display device, in which a vertical axis represents a logic level and a horizontal axis represents time. FIG.
The operation of the above-described conventional liquid crystal display device will be described with reference to the time chart of FIG. The image input signal in and the clock signal S2 are input to the control unit 1, and the control unit 1 outputs an image data signal S1a, an input pulse S1b, a clock signal S1c, and an output enable signal S1d. The image data signal S1a is input to the display signal circuit 3, and the display signal circuit 3 outputs pixel data signals S3-1,..., S3-m. Input pulse S1
b, the clock signal S1c and the output enable signal S1d are input to the scanning signal circuit 4. In the scanning signal circuit 4, when the input pulse S1b moves in synchronization with the clock signal S1c and the output enable signal S1d is in an active mode (for example, high level, hereinafter referred to as "H"), the scanning signals S4-1,. ,
S4-n is output. When the output enable signal S1d is in a non-active mode (for example, low level, hereinafter, referred to as "L"), the scanning signals S4-1,..., S4-n are not output. The pixel data signals S3-1, ..., S3-m and the scanning signals S4-1,
, S4-n are input to the liquid crystal panel 5. LCD panel 5
, S3-m are supplied to the pixel areas selected by the scanning signals S4-1,..., S4-n, and the pixel data signals S3-1,. The corresponding image is displayed.

[0004]

However, the above-mentioned conventional liquid crystal display device has the following problems. FIG. 7 shows that the number of scanning signal lines X1,..., Xn in the liquid crystal display device is 1200, and the number of scanning lines during the image display period of the image input signal in is 10
FIG. 9 is a schematic diagram for explaining an operation when 80 and the total number of scanning lines is 1125. As shown in FIG. 7, in the state [1], for the first time, the pixel data signals S3-1, S3-1 of the first line in the image display period are displayed.
.., A scanning signal when S3-m is written to the liquid crystal panel 5
S4-1 is shown. The output enable signal S1d is always in the active mode. Then, the clock signal
The input pulse S1b is shifted in synchronization with S1c, and the pixel data signals S3-1,..., S3-m for the second line are written to the liquid crystal panel 5. Thus, the pixel data signals S3-1,..., S3-m are written to the liquid crystal panel 5 from the first line to the 1080th line. In the state [2], a scanning signal S4-1080 when the pixel data signals S3-1,..., S3-m on the 1080th line are written to the liquid crystal panel 5 is shown.

Next, a blanking (black band) is written by inputting the clock signal S1c. There are 45 lines in the blanking period, and the line is black during that period. When the next line is reached, the 1126th line is reached and the first line is returned. Therefore, as shown in state [3], the scanning signals S4-1 and S4-1126 for the first and 1126th lines are output. Therefore, the same pixel data signals S3-1,..., S3-m as in the first and subsequent lines are written in the 1126th and subsequent lines. This image is shown in the liquid crystal panel 5. The black part is a blanking period, and the white part is an image display period. In the state [4], an image in which the start of the blanking period is read as the start of the image display period and displayed on the liquid crystal panel 5 is shown. As shown in this state [4], blanking is written above and below the image display period, but an image is displayed below the lower blanking. Therefore, there was a problem that complete blanking could not be written above and below the image display period.

To solve this problem, a scanning signal line X
If the number of 1,..., Xn is larger than the total number of scanning lines in one vertical cycle of the image input signal in, digital signal processing is performed on the image input signal in to increase the number of scanning lines and increase the number of scanning lines.
May be taken. For example, if the number of scanning signal lines X1,..., Xn of the liquid crystal panel 5 is 1200, the number of scanning lines in the image display period of the image input signal in is 1080, and the total number of scanning lines is 1125, the image input signal in is By temporarily storing the data in the frame memory and performing a process of adding a blanking period, a display is performed in which the number of scanning lines in the image display period remains 1080 and the total number of scanning lines becomes 1200. However, when the total number of scanning lines is increased by such digital signal processing, the number of components such as a frame memory and a frame memory control unit increases, resulting in a problem that the configuration becomes complicated and the scale becomes huge. .

[0007] For example, Patent No. 2820061
In the publication, in a liquid crystal panel using a polysilicon technology, a complicated scanning signal circuit is formed on the panel, and a plurality of scanning signals are simultaneously set to an active mode,
It has been proposed to write complete blanking above and below the image display period. However, liquid crystal panels using amorphous silicon technology, which is currently the mainstream, have a significantly slower electron mobility than liquid crystal panels using polysilicon technology, so a complicated scanning signal circuit is configured on the panel. Is not practical. That is, the scanning signal circuit
It is composed of a shift register having a simple structure, and the conventional driving method as shown in FIG. 6 has a problem that a plurality of scanning signals cannot be simultaneously set in the active mode.

The present invention has been made in view of the above circumstances, and when the number of scanning signal lines is larger than the total number of scanning lines in one vertical cycle of an image input signal, a liquid crystal panel using amorphous silicon technology is also provided. It is another object of the present invention to provide a liquid crystal display device capable of writing complete blanking in the upper and lower parts of an image display period while keeping the conventional configuration of the scanning signal circuit, and a driving method thereof.

[0009]

According to a first aspect of the present invention, there is provided a liquid crystal display device having a plurality of data signal lines for inputting pixel data signals and a plurality of data signal lines for inputting scanning signals. A scanning signal line, and a plurality of pixel regions provided at intersections of the data signal lines and the scanning signal lines, and a pixel region selected by the scanning signal among the pixel regions A liquid crystal panel that displays an image corresponding to the pixel data signal by supplying the pixel data signal; a display signal unit that sends the pixel data signal to each of the data signal lines in accordance with an image input signal; Input pulse for the scan signal, and moves in synchronization with the clock signal. When an output command signal is input, the scan signal is transmitted to the respective scan signal lines as the scan pulse. When inputs the image input signal,
Control means for transmitting the input pulse, the clock signal and the output command signal to the scanning signal means, wherein the control means sets the scanning signal lines of the liquid crystal panel to be lower than the scanning lines of one vertical cycle of the image input signal. In many cases, the input pulse, the clock signal, and the output command signal are output in the first operation mode during a vertical image display period of the screen of the liquid crystal panel, and blanking without vertical images in the vertical direction of the screen is performed. In the period, the input pulse, the clock signal, and the output command signal are output in the second operation mode.

According to a second aspect of the present invention, in the liquid crystal display device according to the first aspect, in the first operation mode, the scanning signal means transmits the scanning signal once in one horizontal cycle of the image input signal. Output, and in the second operation mode, the scanning signal means outputs a plurality of the scanning signals simultaneously during the blanking period.

According to a third aspect of the present invention, in the liquid crystal display device according to the first aspect, in the first operation mode, the scanning signal means transmits the scanning signal a plurality of times in one horizontal cycle of the image input signal. Enlarge the image by outputting,
In the second operation mode, the scanning signal unit outputs a plurality of the scanning signals simultaneously during the blanking period.

According to a fourth aspect of the present invention, in the liquid crystal display device according to the first, second or third aspect, in the second operation mode, the scanning signal means transmits a plurality of the scanning signals during the blanking period. It is characterized in that the scanning signal lines are output separately for odd lines and even lines.

According to a fifth aspect of the present invention, there is provided the liquid crystal display device according to the fourth aspect, wherein in the second operation mode, the scanning signal means scans the odd and even lines of each of the scanning signal lines. It is characterized in that the polarity of the signal is reversed.

[0014] The invention according to claim 6 is the first or second invention.
7. The liquid crystal display device according to 3, 4, or 5, wherein the liquid crystal panel is constituted by an active matrix type liquid crystal panel using a thin film transistor using amorphous silicon as an active element.

The invention according to claim 7 relates to a driving method of a liquid crystal display device, wherein when the number of scanning signal lines of the liquid crystal panel is larger than the number of scanning lines of one vertical period of the image input signal, the vertical direction of the screen of the liquid crystal panel. In the image display period, a scanning signal is output once in one horizontal cycle of the image input signal. In a blanking period in which there is no vertical image on the screen of the liquid crystal panel, a plurality of the scanning signals are output in the blanking period. Are simultaneously output.

The invention according to claim 8 relates to a driving method of a liquid crystal display device, wherein when the number of scanning signal lines of the liquid crystal panel is larger than the number of scanning lines of one vertical cycle of the image input signal, the vertical direction of the screen of the liquid crystal panel. In the image display period, the image is enlarged by outputting the scanning signal a plurality of times in one horizontal cycle of the image input signal, and in the blanking period in which there is no vertical image in the vertical direction of the liquid crystal panel screen, the blanking period. And simultaneously outputting a plurality of the scanning signals.

According to a ninth aspect of the present invention, there is provided the driving method of the liquid crystal display device according to the seventh or eighth aspect, wherein a plurality of the scanning signals are supplied to the odd line and the even line of each scanning signal line during the blanking period. It is characterized by being output separately.

The invention according to claim 10 is the invention according to claim 9.
According to the driving method of the liquid crystal display device described above, the polarity of the scanning signal is inverted between an odd line and an even line of each scanning signal line.

[0019]

Embodiments of the present invention will be described below with reference to the drawings. The description will be specifically made using an embodiment. First Embodiment FIG. 1 is a block diagram showing an electric configuration of a liquid crystal display device according to a first embodiment of the present invention. The liquid crystal display device of this embodiment includes a control unit (for example, a control unit) 11 and an oscillation circuit 12, as shown in FIG. The control unit 11 includes a plurality of logic circuits and the like, and includes an image input signal in supplied from the outside and a clock signal S12 supplied from the oscillation circuit 12.
And generates and outputs an image data signal S11a, an input pulse S11b for generating a scanning signal, a clock signal S11c, and an output command signal (for example, an output enable signal) S11d. Further, the control unit 11 controls a scanning signal line of a liquid crystal panel used in the liquid crystal display device to input an image input signal.
In the case where the number of scanning lines is more than one scanning line of one vertical cycle, in the vertical image display period of the screen of the liquid crystal panel, the input pulse S11b, the clock signal S11c, and the output enable signal S11d are output in the first operation mode. In the blanking period where there is no vertical upper and lower images, the input pulse S11b, the clock signal S11c, and the output enable signal S11d are used in the second operation mode.
Is output.

The control section 11 is connected to a display signal means (for example, a display signal circuit) 13 and a scanning signal means (for example, a scanning signal circuit) 14. The display signal circuit 13 receives the image data signal S11a and receives the pixel data signals S13-1,..., S13-m
Is a circuit that generates and outputs The scanning signal circuit 14 has a shift register or the like that receives the input pulse S11b and moves in synchronization with the clock signal S11c, and the output enable signal S1.
When 1d is input, the input pulse S11b is supplied to the scanning signal S14-
1, ..., S14-n. Display signal circuit
On the output side of 13, the data signal lines Y1,.
Is connected, and the liquid crystal panel is connected to the output side of the scanning signal circuit 14.
The 15 scanning signal lines X1,..., Xn are connected. The liquid crystal panel 15 includes data signal lines Y1,..., Ym and scanning signal lines X1,.
.., S14-n among the pixel regions, the pixel data signals S13-1,.
.., S13-m is supplied to display an image. The liquid crystal panel 15 is composed of, for example, an active matrix type liquid crystal panel. An active element formed by a thin film transistor using amorphous silicon and a storage element for storing pixel data signals S13-1,..., S13-m are used as the pixel area. Contains.

In this liquid crystal display device, the image input signal in and the clock signal S12 are input to the control unit 11, and the control unit 11
Output an image data signal S11a, an input pulse S11b, a clock signal S11c, and an output enable signal S11d. The image data signal S11a is input to the display signal circuit 13, and the display signal circuit 13 outputs pixel data signals S13-1,..., S13-m. The input pulse S11b, the clock signal S11c, and the output enable signal S11d are input to the scanning signal circuit 14. In the scanning signal circuit 14, the input pulse S11b moves in synchronization with the clock signal S11c, and the scanning signals S14-1,..., S14-n are output when the output enable signal S11d is "H". , S13-m and the scanning signals S14-1,..., S14-n
Is input to the liquid crystal panel 15. In the liquid crystal panel 15, the pixel data signals S13-1,..., S13-m are supplied to the pixel areas selected by the scanning signals S14-1,. The image corresponding to -m is displayed.

FIGS. 2A and 2B show the operation of the liquid crystal display device of this embodiment when the number of scanning signal lines X1,..., Xn is larger than the total number of scanning lines in one vertical cycle of the image input signal in. FIG. 2A is a time chart of signals of respective units, and FIG. 2B is a schematic diagram for explaining blanking writing. In this figure, the scanning signal lines X1,
, Xn are 1200, and the operation when the number of scanning lines in the image display period of the image input signal in is 1080 and the total number of scanning lines is 1125 is shown. The operation of the liquid crystal display device of this embodiment will be described with reference to FIG. In the state [1] in FIGS. 2A and 2B, the output enable signal S11d becomes “H” and the scanning signal circuit 14 outputs the scanning signal S14-1140.
The last pixel data signal S13-1, ..., S13-m in the image display period for 1080 lines is transmitted from the display signal circuit 13 to the liquid crystal panel.
Entered in 15. During the period of transition from state [1] to state [2] in FIGS. 2 (a) and 2 (b), the output enable signal
S11d becomes “L”, and the scanning signal S14− in the state [1] is output.
1140 goes into non-active mode. At this time, 30 input pulses S1 which are inverted every one pulse of the clock signal S11c
1b is input to the scanning signal circuit 14, and the high-speed clock signal S1
It moves within the scanning signal circuit 14 in synchronization with 1c.

In the state [2] in FIGS. 2A and 2B,
The control section 11 performs the operation in the second operation mode, the output enable signal S11d becomes “H”, and the scanning signal circuit 14 outputs 60 scanning signals S14-1,..., S14-60 in the upper blanking period.
Among them, the odd-numbered 30 scanning signals are output simultaneously. Therefore, blanking is simultaneously written to the upper 30 odd lines of the liquid crystal panel 15. FIG. 2 (a),
In the state [3] in (b), the control unit 11 performs the operation in the second operation mode, the output enable signal S11d becomes “H”, and 30 input pulses S11b are output in the scanning signal circuit 14 by 1 in the scanning signal circuit 14. The scanning signal circuit 14 moves in synchronization with the clock signal S11c, and the scanning signal circuit 14 outputs 60 scanning signals S14-1,.
The even-numbered 30 scanning signals of -60 are output simultaneously. Therefore, blanking is simultaneously written in the upper 30 even lines of the liquid crystal panel 15. The polarities of these scanning signals are opposite to those of the odd 30 scanning signals in the state [2]. In the periods [2] and [3] in FIGS. 2A and 2B, the clock signal S11c having the same cycle as the image display period is supplied to the scanning signal circuit 14 in order to match the image display period and the writing time. Is entered. During the periods of the states [2] and [3], blanking may be written on the liquid crystal panel 15, and therefore may be shorter or longer than one horizontal cycle. During the transition from the state [3] in FIGS. 2A and 2B to the state [4], the output enable signal S11d is at “L”, and the scanning signal is in the non-active mode. At this time, the high-speed clock signal S11c is
14, and 30 input pulses S11b are applied to the clock signal.
It moves to the lower blanking period in synchronization with S11c.

Next, the state [4] in FIGS. 2 (a) and 2 (b)
In this case, the output enable signal S11d becomes “H”, and the scanning signal circuit 14 outputs signals from the 60 lines S14-114 in the lower blanking period.
The odd-numbered 30 scanning signals of 1,..., S14-1200 are output simultaneously. Therefore, the lower 30 of the LCD panel 15
Blanking is simultaneously written to the odd lines of the book.
In the state [5] in FIGS. 2A and 2B, the output enable signal S11d becomes “H”, and the 30 input pulses S11b move in the scanning signal circuit 14 in synchronization with one clock signal S11c. Then, from the scanning signal circuit 14, the lower blanking period 60
, S14-1200, the even-numbered 30 scanning signals are simultaneously output. Therefore, the LCD panel 15
Blanking is simultaneously written to the lower 30 even lines. States [4] and [5] in FIGS. 2 (a) and 2 (b)
In the period, the clock signal S11c having the same cycle as that of the image display period is input to the scanning signal circuit 14 in order to match the image display period with the writing time. The periods in states [4] and [5] may be shorter or longer than one horizontal cycle because blanking may be written on the liquid crystal panel 15.

After the state [5] in FIGS. 2A and 2B,
As shown in FIG. 2A, an input pulse S11b of “H” is input during a period of one clock signal S11c. During the period of transition from state [5] to state [6] in FIG. 2B, the high-speed clock signal S11c is input to the scanning signal circuit. Then, 30 input pulses S11b enter the non-active mode, and one input pulse S11b moves to the beginning of the image display period. In the state [6] in FIGS. 2A and 2B, the control unit 11 performs the operation in the first operation mode, the output enable signal S11d becomes “H”, and the scanning signal circuit 14 outputs the scanning signal S14. ., S13-m of the image display period for 1080 lines is input from the display signal circuit 13 to the liquid crystal panel 15. Similarly, the scanning signal circuit 14 sequentially outputs the scanning signals S14-62,..., S14-1140 once in one horizontal cycle of the image input signal in, and outputs the pixel data signals S13-1,. Circuit 13 to LCD panel 15
Is input to

As described above, in the first embodiment,
When the number of scanning signal lines of the liquid crystal panel 15 is larger than the number of scanning lines of one vertical cycle of the image input signal in, the control unit 11
In the vertical image display period of the fifteen screens, the input pulse S11b, the clock signal S11c, and the output enable signal S11d are output in the first operation mode. Since the input pulse S11b, the clock signal S11c, and the output enable signal S11d are output in the second operation mode, the liquid crystal panel having a relatively simple structure using amorphous silicon technology can be used without using a frame memory or the like. , Complete blanking is written above and below the image display period.

Second Embodiment FIG. 3 is a block diagram showing an electric configuration of a liquid crystal display device according to a second embodiment of the present invention, which is common to the elements in FIG. 1 showing the first embodiment. Are given the same reference numerals. In the liquid crystal display device of this embodiment, a control unit 21 having a different configuration is provided instead of the control unit 11 in FIG. The control unit 21 is, for example, a high definition television (High D
The scanning line of one vertical cycle such as an interlace signal of an efinition television signal (hereinafter, referred to as an “HDTV signal”) has an image input signal of 以下 or less of the scanning signal line of the liquid crystal panel 15.
InH is input, and an input pulse S21b, a clock signal S21c, and an output enable signal S21d are output in the first operation mode in a vertical image display period of the screen of the liquid crystal panel 15. In the first operation mode, the scanning signal circuit
Reference numeral 14 inputs the input pulse S21b, the clock signal S21c, and the output enable signal S21d, and outputs a scanning signal a plurality of times in one horizontal cycle of the image input signal inH. Other configurations are the same as those in FIG.

FIG. 4 is a time chart of signals of respective sections for explaining the operation of the liquid crystal display device of this embodiment, in which a vertical axis represents a logic level and a horizontal axis represents time. In this figure, an interlaced signal of an HDTV signal having 1080 scanning lines and a total scanning line of 1125 during an image display period is used as an image input signal.
The operation when writing as inH is shown. The operation of the liquid crystal display device of this embodiment is significantly different from the operation of the liquid crystal display device of the first embodiment in the following points. That is, in the image display period, the pixel data signal S1 for one line
The clock signal S21c is sent from the control unit 21 to 3-1 ..., S13-m.
Is output twice, and the clock signal S2 is output from the scanning signal circuit 14.
Scan signals S14-k and S14- (k + 1) are sequentially output in synchronization with 1c. Therefore, the same pixel data signals S13-1,..., S13-m
Is written on the liquid crystal panel 15 for two lines, and the image is enlarged. In this case, the output enable signal S21d is not always in the active mode, but the pulse width is reduced and
The pulse widths for the writing times of the first and second pixel data signals S13-1,..., S13-m are the same. Therefore, the rising of the pixel data signals S13-1,..., S13-m inputted to the data signal lines Y1,.
Pixel data signals S13-1, ..., S13-m written for the lines
A luminance difference is not generated in the signal. Others are shown in Figure 1
The same operation as described above is performed.

As described above, in the second embodiment,
The scanning line of one vertical cycle is 1 / of the scanning signal line of the liquid crystal panel 15.
When an image input signal inH of 2 or less is input to the control unit 21, the clock signal S21c is output twice from the control unit 21, and the scanning signal circuit 14 outputs the scanning signal S14 in synchronization with the clock signal S21c. -k, S14- (k + 1) are sequentially output, so that the image is enlarged, and as in the first embodiment, complete images are formed above and below the image display period with a relatively simple configuration. Blanking is written.

Although the embodiment of the present invention has been described in detail with reference to the drawings, the specific configuration is not limited to this embodiment, and there are design changes and the like without departing from the gist of the present invention. Is also included in the present invention. For example, the liquid crystal panel 15 is not limited to the active matrix type, but may be a passive matrix type. In each embodiment, the number of scanning lines of the image input signals in and inH, the number of scanning lines in the blanking period, the number of scanning lines in the image display area, and the number of scanning signal lines of the liquid crystal panel 15 increase or decrease as necessary. May be. In the second embodiment, the number of times of writing the pixel data signals S13-1,..., S13-m depends on the number of scanning signal lines of the liquid crystal panel 15,
The number is not limited to two and may be three or more. The display signal circuit 13 in FIGS. 1 and 3 may be configured to directly input the image input signal in and output the pixel data signals S13-1,..., S13-m. Further, the present invention can be applied to all devices that display an image by supplying a pixel data signal to a pixel region selected by a scanning signal, such as a PDP (plasma display panel).

[0031]

As described above, according to the structure of the present invention, when the number of scanning signal lines of the liquid crystal panel is larger than the number of scanning lines of one vertical cycle of the image input signal, the control means controls the screen of the liquid crystal panel. In the vertical image display period, the input pulse, the clock signal, and the output command signal are output in the first operation mode. In the blanking period in which there is no vertical image in the vertical direction of the screen, the second operation mode is used. Since the input pulse, the clock signal, and the output enable signal are output, an image can be displayed on a liquid crystal panel having a relatively simple configuration using amorphous silicon technology without performing digital signal processing using a frame memory or the like. Complete blanking can be written above and below the display period. further,
When an image input signal equal to or less than の of the number of vertical pixels of the liquid crystal panel is input to the control means, a clock signal is output from the control means a plurality of times, and the scanning signal is synchronized with the clock signal from the scanning signal means. Since the image is output a plurality of times, the image can be enlarged.

[Brief description of the drawings]

FIG. 1 is a block diagram illustrating an electrical configuration of a liquid crystal display device according to a first embodiment of the present invention.

FIG. 2 is a schematic diagram for explaining the operation of the liquid crystal display device of FIG.

FIG. 3 is a block diagram illustrating an electrical configuration of a liquid crystal display device according to a second embodiment of the present invention.

4 is a time chart for explaining an operation of the liquid crystal display device of FIG.

FIG. 5 is a block diagram illustrating an electrical configuration of a conventional liquid crystal display device.

FIG. 6 is a time chart for explaining the operation of the liquid crystal display device of FIG.

FIG. 7 is a schematic diagram for explaining the operation of the liquid crystal display device of FIG.

[Explanation of symbols]

 11, 21 Control unit 13 Display signal circuit 14 Scan signal circuit 15 Liquid crystal panel

Continued on the front page F term (reference) 2H093 NA16 NA31 NA41 NC22 NC29 NC34 ND41 5C006 AB03 AC02 AC24 AC29 AF36 AF41 AF72 AF73 BB16 BC03 BC06 BC13 5C080 AA10 BB05 DD01 DD30 EE21 EE32 FF09 JJ02 JJ04 KK02 KK43 KK43

Claims (10)

[Claims] 1. A plurality of data signal lines for inputting pixel data signals, a plurality of scanning signal lines for inputting scanning signals, and a plurality of scanning signal lines provided at intersections of the data signal lines and the scanning signal lines. A liquid crystal panel having a pixel area and displaying an image corresponding to the pixel data signal by supplying the pixel data signal to a pixel area selected by the scanning signal among the pixel areas; and an image input signal. A display signal means for sending the pixel data signal to each of the data signal lines in response to the input signal; inputting an input pulse for generating a scanning signal; moving in synchronization with a clock signal; Scanning signal means for sending the input pulse as the scanning signal to each of the scanning signal lines; and inputting the image input signal, and outputting the input pulse, the clock signal, and the output command signal. Control means for sending the signal to the scanning signal means, the control means comprising: when the number of scanning signal lines of the liquid crystal panel is greater than the number of scanning lines of one vertical cycle of the image input signal, The input pulse, the clock signal, and the output command signal are output in the first operation mode during the image display period in the horizontal direction, and the input pulse is output in the second operation mode during the blanking period in which there is no vertical image in the vertical direction of the screen. And a clock signal and an output command signal. 2. In the first operation mode, the scanning signal unit outputs the scanning signal once in one horizontal cycle of the image input signal, while in the second operation mode, the scanning signal unit outputs the scanning signal. 2. The liquid crystal display device according to claim 1, wherein a plurality of the scanning signals are output simultaneously during the blanking period. 3. In the first operation mode, the scanning signal means enlarges the image by outputting the scanning signal a plurality of times in one horizontal period of the image input signal, while the second operation mode 2. The liquid crystal display device according to claim 1, wherein said scanning signal means outputs a plurality of said scanning signals simultaneously during said blanking period. 4. In the second operation mode, the scanning signal means outputs a plurality of the scanning signals in the blanking period by dividing the scanning signals into odd lines and even lines of each scanning signal line. The liquid crystal display device according to claim 1, 2 or 3. 5. The scanning mode according to claim 4, wherein in the second operation mode, the scanning signal means reverses the polarity of the scanning signal between an odd line and an even line of each scanning signal line. Liquid crystal display. 6. The liquid crystal panel according to claim 1, wherein the liquid crystal panel comprises an active matrix type liquid crystal panel using a thin film transistor using amorphous silicon as an active element.
6. The liquid crystal display device according to 3, 4 or 5. 7. In a case where the number of scanning signal lines of the liquid crystal panel is larger than the number of scanning lines of one vertical cycle of the image input signal, one horizontal cycle of the image input signal is one in a vertical image display period of the screen of the liquid crystal panel. A driving method for a liquid crystal display device, comprising: outputting a first scanning signal; and simultaneously outputting a plurality of the scanning signals during the blanking period in a blanking period in which there is no vertical image on the screen of the liquid crystal panel. . 8. When the number of scanning signal lines of the liquid crystal panel is larger than the number of scanning lines of one vertical cycle of the image input signal, a plurality of scanning signal lines are provided in one horizontal cycle of the image input signal during a vertical image display period of the screen of the liquid crystal panel. An image is enlarged by outputting a multiple scanning signal, and a plurality of the scanning signals are simultaneously output during the blanking period in a blanking period in which there is no image above and below in the vertical direction of the screen of the liquid crystal panel. A method for driving a liquid crystal display device. 9. The driving of the liquid crystal display device according to claim 7, wherein during the blanking period, a plurality of the scanning signals are output by dividing the scanning signal lines into odd lines and even lines. Method. 10. The driving method of a liquid crystal display device according to claim 9, wherein the polarity of the scanning signal is reversed between the odd line and the even line of each scanning signal line.